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Bikia V, Rovas G, Anagnostopoulos S, Stergiopulos N. On the similarity between aortic and carotid pressure diastolic decay: a mathematical modelling study. Sci Rep 2023; 13:10775. [PMID: 37402771 DOI: 10.1038/s41598-023-37622-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 06/24/2023] [Indexed: 07/06/2023] Open
Abstract
Aortic diastolic pressure decay (DPD) has been shown to have considerable pathophysiological relevance in the assessment of vascular health, as it is significantly affected by arterial stiffening. Nonetheless, the aortic pressure waveform is rarely available and hence the utility of the aortic DPD is limited. On the other hand, carotid blood pressure is often used as a surrogate of central (aortic) blood pressure in cardiovascular monitoring. Although the two waveforms are inherently different, it is unknown whether the aortic DPD shares a common pattern with the carotid DPD. In this study, we compared the DPD time constant of the aorta (aortic RC) and the DPD time constant of the carotid artery (carotid RC) using an in-silico-generated healthy population from a previously validated one-dimensional numerical model of the arterial tree. Our results demonstrated that there is near-absolute agreement between the aortic RC and the carotid RC. In particular, a correlation of ~ 1 was reported for a distribution of aortic/carotid RC values equal to 1.76 ± 0.94 s/1.74 ± 0.87 s. To the best of our knowledge, this is the first study to compare the DPD of the aortic and the carotid pressure waveform. The findings indicate a strong correlation between carotid DPD and aortic DPD, supported by the examination of curve shape and the diastolic decay time constant across a wide range of simulated cardiovascular conditions. Additional investigation is required to validate these results in human subjects and assess their applicability in vivo.
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Affiliation(s)
- Vasiliki Bikia
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland.
| | - Georgios Rovas
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | - Sokratis Anagnostopoulos
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | - Nikolaos Stergiopulos
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
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Çelikbudak Orhon C, Stergiopulos N, Noble S, Giannakopoulos G, Müller H, Adamopoulos D. The Impact of Left Ventricular Performance and Afterload on the Evaluation of Aortic Valve Stenosis: A 1D Mathematical Modeling Approach. Bioengineering (Basel) 2023; 10:bioengineering10040425. [PMID: 37106613 PMCID: PMC10136235 DOI: 10.3390/bioengineering10040425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/22/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
The transaortic valvular pressure gradient (TPG) plays a central role in decision-making for patients suffering from severe aortic stenosis. However, the flow-dependence nature of the TPG makes the diagnosis of aortic stenosis challenging since the markers of cardiac performance and afterload present high physiological interdependence and thus, isolated effects cannot be measured directly in vivo. We used a validated 1D mathematical model of the cardiovascular system, coupled with a model of aortic stenosis, to assess and quantify the independent effect of the main left ventricular performance parameters (end-systolic (Ees) and end-diastolic (Eed) elastance) and principal afterload indices (total vascular resistance (TVR) and total arterial compliance (TAC)) on the TPG for different levels of aortic stenosis. In patients with critical aortic stenosis (aortic valve area (AVA) ≤ 0.6 cm2), a 10% increase of Eed from the baseline value was associated with the most important effect on the TPG (−5.6 ± 0.5 mmHg, p < 0.001), followed by a similar increase of Ees (3.4 ± 0.1 mmHg, p < 0.001), in TAC (1.3 ±0.2 mmHg, p < 0.001) and TVR (−0.7 ± 0.04 mmHg, p < 0.001). The interdependence of the TPG left ventricular performance and afterload indices become stronger with increased aortic stenosis severity. Disregarding their effects may lead to an underestimation of stenosis severity and a potential delay in therapeutic intervention. Therefore, a comprehensive evaluation of left ventricular function and afterload should be performed, especially in cases of diagnostic challenge, since it may offer the pathophysiological mechanism that explains the mismatch between aortic severity and the TPG.
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3
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Ventriculo-arterial coupling in the intensive cardiac care unit: A non-invasive prognostic parameter. Int J Cardiol 2021; 348:85-89. [PMID: 34933063 DOI: 10.1016/j.ijcard.2021.12.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 11/29/2021] [Accepted: 12/14/2021] [Indexed: 12/22/2022]
Abstract
AIMS The aim of this study was to investigate the relationship between ventriculo-arterial coupling (VAC) and in-hospital outcomes and to assess the prognostic value of VAC in critically ill patients. METHODS AND RESULTS A total of 329 consecutive patients (mean age 66,7 ± 15.5 years, 66.9% male) admitted to the intensive cardiac care unit of the Sandro Pertini Hospital, Rome (Italy) between January 2019 and December 2019, were included in the study. All patients underwent blood pressure measurement and non-invasive, echocardiography-derived estimates of left ventricular end-systolic elastance (Ees), arterial elastance (Ea) and VAC in a single-beat determination using the iElastance© application. In-hospital events related to acute heart failure and hypoperfusion were recorded and need for invasive ventilation, intra-aortic balloon pump, renal replacement therapy and death were considered as composite. Overall, 39 patients (11,8%) experienced in-hospital complications (group C), and 290 (88,2%) did not (group NoC). Ea and VAC were found to be significantly higher in group C than in group NoC, and a trend toward decreased Ees was observed in group C. VAC was a strong and independent predictor of in-hospital clinical outcome both at univariable and multivariable analysis adjusted for comorbidities [OR (95% CI): 1.868 (1.141-3.059); P = 0.013] and hemodynamic parameters [OR (95% CI): 1674 (1018-2755); P = 0.042]. CONCLUSION VAC might be an additional non-invasive prognosticator of outcome in critically ill patients.
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Yokoyama H, Yamanaka F, Shishido K, Ochiai T, Yokota S, Moriyama N, Watanabe Y, Shirai S, Tada N, Araki M, Yashima F, Naganuma T, Ueno H, Tabata M, Mizutani K, Takagi K, Yamamoto M, Saito S, Hayashida K. Prognostic Value of Ventricular-Arterial Coupling After Transcatheter Aortic Valve Replacement on Midterm Clinical Outcomes. J Am Heart Assoc 2021; 10:e019267. [PMID: 34533038 PMCID: PMC8649497 DOI: 10.1161/jaha.120.019267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Ventricular‐arterial coupling predicts outcomes in patients with heart failure. The arterial elastance to end‐systolic elastance ratio (Ea/Ees) is a noninvasively assessed index that reflects ventricular‐arterial coupling. We aimed to determine the prognostic value of ventricular‐arterial coupling assessed through Ea/Ees after transcatheter aortic valve replacement to predict clinical events. Methods and Results We retrieved data on 1378 patients (70% women) who underwent transcatheter aortic valve replacement between October 2013 and May 2017 from the OCEAN‐TAVI (Optimized transCathEter vAlvular iNtervention) Japanese multicenter registry. We determined the association between Ea/Ees and the composite end point of hospitalization for heart failure and cardiovascular death by classifying the patients into quartiles based on Ea/Ees values (group 1: <0.326; group 2: 0.326–0.453; group 3: 0.453–0.666; and group 4: >0.666) during the midterm follow‐up after transcatheter aortic valve replacement. During a median follow‐up period of 736 days (interquartile range, 414–956), there were 247 (17.9%) all‐cause deaths, 89 (6.5%) cardiovascular deaths, 130 (9.4%) hospitalizations for heart failure, and 199 (14.4%) composite events of hospitalization for heart failure and cardiovascular death. The incidence of the composite end point was significantly higher in group 2 (hazard ratio [HR], 1.76; 95% CI, 1.08–2.87 [P=0.024]), group 3 (HR, 2.43; 95% CI, 1.53–3.86 [P<0.001]), and group 4 (HR, 2.89; 95% CI, 1.83–4.57 [P<0.001]) than that in group 1. On adjusted multivariable Cox analysis, Ea/Ees was significantly associated with composite events (HR, 1.47 per 1‐unit increase; 95% CI, 1.08–2.01 [P=0.015]). Conclusions These findings suggest that a higher Ea/Ees at discharge after transcatheter aortic valve replacement is associated with adverse clinical outcomes during midterm follow‐up. Registration URL: https://www.upload.umin.ac.jp/. Unique identifier: UMIN000020423.
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Affiliation(s)
- Hiroaki Yokoyama
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Futoshi Yamanaka
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan.,Department of Cardiovascular Medicine Kokura Memorial Hospital Kitakyushu Japan
| | - Koki Shishido
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Tomoki Ochiai
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Shohei Yokota
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Noriaki Moriyama
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Yusuke Watanabe
- Department of Cardiology Teikyo University School of Medicine Tokyo Japan
| | - Shinichi Shirai
- Department of Cardiology Sendai Kousei Hospital Sendai Japan
| | - Norio Tada
- Department of Cardiology Saiseikai Yokohama City Eastern Hospital Yokohama Japan
| | - Motoharu Araki
- Department of Cardiology Saiseikai Utsunomiya Hospital Utsunomiya Japan
| | - Fumiaki Yashima
- Department of Cardiovascular Medicine Graduate School of Medical Sciences Kumamoto University Kumamoto Japan
| | - Toru Naganuma
- Department of Cardiovascular Medicine Kokura Memorial Hospital Kitakyushu Japan.,Department of Cardiology New Tokyo Hospital Matsudo Japan
| | - Hiroshi Ueno
- Department of Cardiovascular Medicine Toyama University Hospital Toyama Japan
| | - Minoru Tabata
- Department of Cardiovascular Surgery Tokyobay Urayasu Ichikawa Medical Center Urayasu Japan
| | - Kazuki Mizutani
- Department of Cardiovascular Medicine Osaka City University Hospital Osaka Japan
| | - Kensuke Takagi
- Department of Cardiology Ogaki Municipal Hospital Ogaki Japan
| | - Masanori Yamamoto
- Department of Cardiology Nagoya Heart Center Nagoya Japan.,Department of Cardiology Toyohashi Heart Center Toyohashi Japan
| | - Shigeru Saito
- Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
| | - Kentaro Hayashida
- Department of Cardiology Keio University School of Medicine Tokyo Japan
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Abstract
BACKGROUND Clinical and experimental evidence regarding the influence of heart rate (HR) on arterial stiffness and its surrogate marker carotid-to-femoral pulse wave velocity (cf-PWV) is conflicting. We aimed to evaluate the effect of HR on cf-PWV measurement under controlled haemodynamic conditions and especially with respect to blood pressure (BP) that is a strong determinant of arterial stiffness. METHOD Fifty-nine simulated cases were created using a previously validated in-silico model. For each case, cf-PWV was measured at five HR values, 60, 70, 80, 90, 100 bpm. With increasing HR, we assessed cf-PWV under two scenarios: with BP free to vary in response to HR increase, and with aortic DBP (aoDBP) fixed to its baseline value at 60 bpm, by modifying total peripheral resistance accordingly. Further, we quantified the importance of arterial compliance (C) on cf-PWV changes caused by increasing HR. RESULTS When BP was left free to vary with HR, a significant HR-effect on cf-PWV (0.66 ± 0.24 m/s per 10 bpm, P < 0.001) was observed. This effect was reduced to 0.21 ± 0.14 m/s per 10 bpm (P = 0.048) when aoDBP was maintained fixed with increasing HR. The HR-effect on the BP-corrected cf-PWV was higher in the case of low C = 0.8 ± 0.3 ml/mmHg (0.26 ± 0.15 m/s per 10 bpm, P = 0.014) than the case of higher C = 1.7 ± 0.5 ml/mmHg (0.16 ± 0.07 m/s per 10 bpm, P = 0.045). CONCLUSION Our findings demonstrated that relatively small HR changes may only slightly affect the cf-PWV. Nevertheless, in cases wherein HR might vary at a greater extent, a more clinically significant impact on cf-PWV should be considered.
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Bikia V, Adamopoulos D, Pagoulatou S, Rovas G, Stergiopulos N. AI-Based Estimation of End-Systolic Elastance From Arm-Pressure and Systolic Time Intervals. Front Artif Intell 2021; 4:579541. [PMID: 33937742 PMCID: PMC8079739 DOI: 10.3389/frai.2021.579541] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 02/03/2021] [Indexed: 12/15/2022] Open
Abstract
Left ventricular end-systolic elastance (Ees) is a major determinant of cardiac systolic function and ventricular-arterial interaction. Previous methods for the Ees estimation require the use of the echocardiographic ejection fraction (EF). However, given that EF expresses the stroke volume as a fraction of end-diastolic volume (EDV), accurate interpretation of EF is attainable only with the additional measurement of EDV. Hence, there is still need for a simple, reliable, noninvasive method to estimate Ees. This study proposes a novel artificial intelligence—based approach to estimate Ees using the information embedded in clinically relevant systolic time intervals, namely the pre-ejection period (PEP) and ejection time (ET). We developed a training/testing scheme using virtual subjects (n = 4,645) from a previously validated in-silico model. Extreme Gradient Boosting regressor was employed to model Ees using as inputs arm cuff pressure, PEP, and ET. Results showed that Ees can be predicted with high accuracy achieving a normalized RMSE equal to 9.15% (r = 0.92) for a wide range of Ees values from 1.2 to 4.5 mmHg/ml. The proposed model was found to be less sensitive to measurement errors (±10–30% of the actual value) in blood pressure, presenting low test errors for the different levels of noise (RMSE did not exceed 0.32 mmHg/ml). In contrast, a high sensitivity was reported for measurements errors in the systolic timing features. It was demonstrated that Ees can be reliably estimated from the traditional arm-pressure and echocardiographic PEP and ET. This approach constitutes a step towards the development of an easy and clinically applicable method for assessing left ventricular systolic function.
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Affiliation(s)
- Vasiliki Bikia
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | | | - Stamatia Pagoulatou
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | - Georgios Rovas
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
| | - Nikolaos Stergiopulos
- Laboratory of Hemodynamics and Cardiovascular Technology, Institute of Bioengineering, Swiss Federal Institute of Technology, Lausanne, Switzerland
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7
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Noninvasive estimation of aortic hemodynamics and cardiac contractility using machine learning. Sci Rep 2020; 10:15015. [PMID: 32929108 PMCID: PMC7490416 DOI: 10.1038/s41598-020-72147-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 08/13/2020] [Indexed: 02/07/2023] Open
Abstract
Cardiac and aortic characteristics are crucial for cardiovascular disease detection. However, noninvasive estimation of aortic hemodynamics and cardiac contractility is still challenging. This paper investigated the potential of estimating aortic systolic pressure (aSBP), cardiac output (CO), and end-systolic elastance (Ees) from cuff-pressure and pulse wave velocity (PWV) using regression analysis. The importance of incorporating ejection fraction (EF) as additional input for estimating Ees was also assessed. The models, including Random Forest, Support Vector Regressor, Ridge, Gradient Boosting, were trained/validated using synthetic data (n = 4,018) from an in-silico model. When cuff-pressure and PWV were used as inputs, the normalized-RMSEs/correlations for aSBP, CO, and Ees (best-performing models) were 3.36 ± 0.74%/0.99, 7.60 ± 0.68%/0.96, and 16.96 ± 0.64%/0.37, respectively. Using EF as additional input for estimating Ees significantly improved the predictions (7.00 ± 0.78%/0.92). Results showed that the use of noninvasive pressure measurements allows estimating aSBP and CO with acceptable accuracy. In contrast, Ees cannot be predicted from pressure signals alone. Addition of the EF information greatly improves the estimated Ees. Accuracy of the model-derived aSBP compared to in-vivo aSBP (n = 783) was very satisfactory (5.26 ± 2.30%/0.97). Future in-vivo evaluation of CO and Ees estimations remains to be conducted. This novel methodology has potential to improve the noninvasive monitoring of aortic hemodynamics and cardiac contractility.
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8
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Capone CA, Lamour JM, Lorenzo J, Tria B, Ye K, Hsu DT, Mahgerefteh J. Ventricular Arterial Coupling: A Novel Echocardiographic Risk Factor for Disease Progression in Pediatric Dilated Cardiomyopathy. Pediatr Cardiol 2019; 40:330-338. [PMID: 30415380 DOI: 10.1007/s00246-018-2021-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 11/01/2018] [Indexed: 11/25/2022]
Abstract
In adult heart failure (HF) patients, a higher ventricular arterial (VA) coupling ratio measured non-invasively is associated with worse HF prognosis and response to treatment. There are no data regarding the relationship of VA coupling to outcome in pediatric dilated cardiomyopathy (DCM) patients. We investigated the association of VA coupling ratio with worse outcome (mechanical circulatory support, transplant, or death) in 48 children with DCM and 97 age-gender matched controls. Mean age at presentation was 9 ± 7 years; DCM patients had a higher arterial elastance (3.8 ± 1.7 vs 2.7 ± 0.7 respectively p = 0.001), a lower LV elastance (1.1 ± 0.65 vs 4.5 ± 1.4, respectively p = 0.001) and higher VA coupling ratio (5.0 ± 3.9 vs 0.34 ± 0.14, respectively p = 0.001). Outcome events occurred in 27/48 (56%) patients. Patients with an outcome event had a higher NYHA class (p = 0.001), lower LV elastance (0.8 ± 0.47 vs 1.6 ± 0.57, respectively p = 0.001), higher arterial elastance (4.5 ± 1.8 vs 2.9 ± 1.1, respectively p = 0.002), and a higher VA coupling ratio (7.1 ± 3.8 vs 2.2 ± 1.5, respectively p = 0.001) compared to those without. In a multivariate CART analysis, VA coupling was the top and only discriminator of poor outcome. In conclusion, a higher VA coupling ratio is associated with worse outcome in pediatric patients with DCM. VA coupling is promising as a bedside analysis tool that may provide insight into the mechanisms of HF in pediatric DCM and identify potential targets for therapy.
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Affiliation(s)
- Christine A Capone
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA.
| | - Jacqueline M Lamour
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA
| | - Josemiguel Lorenzo
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA
| | - Barbara Tria
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA
| | - Kenny Ye
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Daphne T Hsu
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA
| | - Joseph Mahgerefteh
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, 3415 Bainbridge Avenue, R1, 10467, Bronx, NY, USA
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9
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Estimating Left Ventricular Elastance from Aortic Flow Waveform, Ventricular Ejection Fraction, and Brachial Pressure: An In Silico Study. Ann Biomed Eng 2018; 46:1722-1735. [DOI: 10.1007/s10439-018-2072-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 06/08/2018] [Indexed: 11/26/2022]
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Goya S, Wada T, Shimada K, Hirao D, Tanaka R. Dose-dependent effects of isoflurane and dobutamine on cardiovascular function in dogs with experimental mitral regurgitation. Vet Anaesth Analg 2018; 45:432-442. [PMID: 29887228 DOI: 10.1016/j.vaa.2018.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 03/14/2018] [Accepted: 03/30/2018] [Indexed: 10/17/2022]
Abstract
OBJECTIVE To investigate the dose-dependent effects of isoflurane and dobutamine on haemodynamics in dogs with experimentally induced mitral valve insufficiency (MI). STUDY DESIGN Experimental, dose-response study. ANIMALS Six healthy Beagle dogs. METHODS Dogs with surgically induced MI were anaesthetized once. First, anaesthesia was maintained at an end-tidal isoflurane concentration (Fe'Iso) 1.0% (ISO1.0) for 20 minutes. Then, dobutamine was infused successively at 2, 4, 8 and 12 μg kg-1 minute-1 (DOB2-12) for 10 minutes at each dose rate. Measurements were recorded at each stage. Dobutamine was discontinued and Fe'Iso was increased to 1.5% (ISO1.5) for 20 minutes. Dobutamine was administered similarly to ISO1.0, and cardiovascular variables were recorded. The same sequence was repeated for Fe'Iso 2.0% (ISO2.0). Aortic pressure (AoP) and left atrial pressure (LAP) were recorded by radiotelemetry. The combination method of the pressure-volume loop analysis and transoesophageal echocardiography was used to measure cardiovascular variables: end-systolic elastance (Ees), effective arterial elastance (Ea), Ea/Ees, forward stroke volume (FSV), heart rate (HR), and cardiac output (CO). RESULTS High isoflurane concentration resulted in reduced Ees and increased Ea/Ees, which indicated low arterial pressure. High-dose dobutamine administration resulted in increased Ees and FSV at all isoflurane concentrations. In ISO1.5 and ISO2.0, HR was lower at DOB4 than baseline (BL) but increased at DOB12 compared with DOB4. CO increased at ≥ DOB8 compared with BL. In ISO1.5 and ISO2.0, systolic and mean AoP increased at ≥ DOB4 and ≥ DOB8, respectively. LAP did not change under all conditions. CONCLUSIONS AND CLINICAL RELEVANCE The dose-dependent hypotensive effect of isoflurane in MI dogs was mainly derived from the decrease in contractility. Dobutamine increased AoP without increasing LAP by increasing the contractility attenuated by isoflurane. Our findings may improve the cardiovascular management of dogs with MI undergoing general anaesthesia with isoflurane.
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Affiliation(s)
- Seijirow Goya
- Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Tomoki Wada
- Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Kazumi Shimada
- Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Daiki Hirao
- Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Ryou Tanaka
- Department of Veterinary Surgery, Faculty of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan.
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Wei ZY, Cui BR, Cui X, Wu YL, Fu Y, Liu LP, Piao HR. Design, synthesis, and negative inotropic evaluation of 4-phenyl-1H
-1,2,4-triazol-5(4H
)-one derivatives containing triazole or piperazine moieties. Chem Biol Drug Des 2016; 89:47-60. [DOI: 10.1111/cbdd.12828] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/15/2016] [Accepted: 07/21/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Zhi-Yu Wei
- Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules; Ministry of Education; Yanbian University College of Pharmacy; Yanji China
| | - Bai-Ri Cui
- Department of Orthopedics; Yanbian University Hospital; Yanji China
| | - Xun Cui
- Yanbian University College of Medicine; Yanji China
| | - Yan-Ling Wu
- Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules; Ministry of Education; Yanbian University College of Pharmacy; Yanji China
| | - Yang Fu
- Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules; Ministry of Education; Yanbian University College of Pharmacy; Yanji China
| | - Li-Ping Liu
- Yanbian University College of Medicine; Yanji China
| | - Hu-Ri Piao
- Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules; Ministry of Education; Yanbian University College of Pharmacy; Yanji China
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Fricke K, Konecny F, El-Warrak A, Hodgson C, Cadieux-Pitre H, Hill T, Sobot R. In-vivo characterization of left-ventricle pressure-volume telemetry system in swine model. Biomed Microdevices 2016; 18:75. [PMID: 27492638 DOI: 10.1007/s10544-016-0094-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We present in-vivo study related to the use of our implantable RF telemetry system for pressure-volume (PV) cardiac monitoring in a animal subject. We implant a commercial MEMS PV sensor into the subject's heart left-ventricle (LV), while the telemetry system is implanted outside of the heart and connected to the sensor with a 7-microwires tether. The RF telemetry system is suitable for commercial application in medium sized subjects, its total volume of 2.475cm(3) and a weight of 4.0g. Our designed system is 58 % smaller in volume, 44 % in weight and has a 55 % reduction in sampling power over the last reported research in PV telemetry. In-vivo data was captured in both an acute and a freely moving setting over a 24 hour period. We experimentally demonstrated viability of the methodology that includes the surgical procedure and real-time monitoring of the in-vivo data in a freely moving subject. Further improvements in catheter design will improve the data quality and safety of the subject. This real-time implantable technology allows for researchers to quantify cardiac pathologies by extracting real-time pressure-volume loops, wirelessly from within freely moving subjects.
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Affiliation(s)
- Kyle Fricke
- Department of Electrical and Computer Engineering at Western University, London, ON, Canada.
| | | | | | | | | | - Tracy Hill
- Animal Care and Veterinary Services, Western University, London, ON, Canada
| | - Robert Sobot
- Department of Electrical and Computer Engineering at Western University, London, ON, Canada.,ENSEA/University Cergy-Pontoise/CNRS, Pontoise, France
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Matsumoto K, Tanaka H, Ooka J, Motoji Y, Sawa T, Mochizuki Y, Ryo K, Tatsumi K, Hirata KI. Significant prognostic impact of improvement in ventriculo-arterial coupling induced by dobutamine stress on cardiovascular outcome for patients with dilated cardiomyopathy. Eur Heart J Cardiovasc Imaging 2015; 17:1296-1304. [PMID: 26705483 DOI: 10.1093/ehjci/jev327] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 11/19/2015] [Indexed: 01/02/2023] Open
Abstract
AIMS The purpose of this study was to investigate the prognostic impact of the changes in ventriculo-arterial (VA) coupling during dobutamine stress on the cardiovascular events for patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS For this study, 89 DCM patients with ejection fractions of 32 ± 10% and 30 normal controls were recruited. Ees was estimated with the non-invasive single-beat method using three-dimensional echocardiography at rest and during dobutamine stress (20 μg/kg/min). Effective arterial elastance (Ea) was calculated as left ventricular (LV) end-systolic pressure divided by stroke volume, and VA coupling was calculated as Ea/Ees. Event-free survival was then tracked for 32 months. At baseline, VA coupling was far from optimal in patients with DCM compared with controls (Ea/Ees: 2.49 ± 1.02 vs. 1.04 ± 0.21, P < 0.001). During the follow-up period, 22 patients developed adverse cardiovascular events. During dobutamine stress, VA coupling was significantly improved in patients without cardiovascular events (from 2.47 ± 1.09 to 1.59 ± 0.68, P < 0.001), but remained unchanged in those with cardiovascular events. A multivariate Cox proportional-hazards analysis revealed that age, NYHA functional class (>II), and the change in VA coupling during dobutamine stress were the independent determinants of cardiovascular events (P < 0.05, <0.01, and <0.001, respectively). When patients were divided into two subgroups based on the finding of receiver operating characteristic curve analysis, patients with good VA coupling reserve (cut-off: change in VA coupling> 0.29) showed significantly favourable event-free survival than those with poor VA coupling reserve (P < 0.001). CONCLUSIONS Improvement in VA coupling during dobutamine stress is an important determinant of cardiovascular outcome for patients with DCM.
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Affiliation(s)
- Kensuke Matsumoto
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Hidekazu Tanaka
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Junichi Ooka
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Yoshiki Motoji
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Takuma Sawa
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Yasuhide Mochizuki
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Keiko Ryo
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Kazuhiro Tatsumi
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Ken-Ichi Hirata
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
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Aslanger E, Assous B, Bihry N, Beauvais F, Logeart D, Cohen-Solal A. Effects of Cardiopulmonary Exercise Rehabilitation on Left Ventricular Mechanical Efficiency and Ventricular-Arterial Coupling in Patients With Systolic Heart Failure. J Am Heart Assoc 2015; 4:e002084. [PMID: 26464425 PMCID: PMC4845119 DOI: 10.1161/jaha.115.002084] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Success of cardiac rehabilitation (CR) is generally assessed by the objective improvement in peak volume of inhaled oxygen (VO2) measured by cardiopulmonary exercise test (CPX). However, cardiac mechanical efficiency and ventricular-arterial coupling (VAC) are the other important dimensions of the heart failure pathophysiology, which are not included in CPX-derived data. The effect of cardiac rehabilitation on left ventricular (LV) efficiency or VAC in unselected heart failure patients has not been studied thus far. METHODS AND RESULTS Thirty patients with an ejection fraction of ≤45% were recruited for 20 sessions of exercise-based CR. Noninvasive LV pressure-volume loops were constructed and VAC was calculated with the help of applanation tonometry and echocardiography before and after CR. VAC showed an improved mechanical efficiency profile and increased significantly from 0.56±0.18 to 0.67±0.21 (P=0.02). LV mechanical efficiency improved from 43.9±9.1% to 48.8±9.1% (P=0.01). The change in peak VO2 was not in a significant correlation with the change in VAC (r=-0.18; P=0.31), mechanical efficiency (r=-0.16, P=0.39), or the change in ejection fraction (r=-0.07; P=0.68). CONCLUSIONS CR is associated with an improvement in VAC and LV mechanical efficiency in heart failure patients. Further studies are needed to determine the incremental value of VAC and mechanical efficiency over CPX-derived data in predicting clinical outcomes.
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Affiliation(s)
- Emre Aslanger
- Department of Cardiology, Department of Cardiology, Yeditepe University Hospital, Ataşehir, Lariboisière Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France (E.A., B.A., N.B.)
| | - Benjamin Assous
- Department of Cardiology, Department of Cardiology, Yeditepe University Hospital, Ataşehir, Lariboisière Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France (E.A., B.A., N.B.)
| | - Nicolas Bihry
- Department of Cardiology, Department of Cardiology, Yeditepe University Hospital, Ataşehir, Lariboisière Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France (E.A., B.A., N.B.)
| | - Florence Beauvais
- Lariboisière Hospital, Department of Cardiology, Assistance Publique-Hôpitaux de Paris (AP-HP), UMR-S 942, Université Paris Diderot, DHU FIRE, Paris, France (F.B., D.L., A.C.S.)
| | - Damien Logeart
- Lariboisière Hospital, Department of Cardiology, Assistance Publique-Hôpitaux de Paris (AP-HP), UMR-S 942, Université Paris Diderot, DHU FIRE, Paris, France (F.B., D.L., A.C.S.)
| | - Alain Cohen-Solal
- Lariboisière Hospital, Department of Cardiology, Assistance Publique-Hôpitaux de Paris (AP-HP), UMR-S 942, Université Paris Diderot, DHU FIRE, Paris, France (F.B., D.L., A.C.S.)
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Warriner DR, Brown AG, Varma S, Sheridan PJ, Lawford P, Hose DR, Al-Mohammad A, Shi Y. Closing the loop: modelling of heart failure progression from health to end-stage using a meta-analysis of left ventricular pressure-volume loops. PLoS One 2014; 9:e114153. [PMID: 25479594 PMCID: PMC4257583 DOI: 10.1371/journal.pone.0114153] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 11/03/2014] [Indexed: 11/18/2022] Open
Abstract
Introduction The American Heart Association (AHA)/American College of Cardiology (ACC) guidelines for the classification of heart failure (HF) are descriptive but lack precise and objective measures which would assist in categorising such patients. Our aim was two fold, firstly to demonstrate quantitatively the progression of HF through each stage using a meta-analysis of existing left ventricular (LV) pressure-volume (PV) loop data and secondly use the LV PV loop data to create stage specific HF models. Methods and Results A literature search yielded 31 papers with PV data, representing over 200 patients in different stages of HF. The raw pressure and volume data were extracted from the papers using a digitising software package and the means were calculated. The data demonstrated that, as HF progressed, stroke volume (SV), ejection fraction (EF%) decreased while LV volumes increased. A 2-element lumped parameter model was employed to model the mean loops and the error was calculated between the loops, demonstrating close fit between the loops. The only parameter that was consistently and statistically different across all the stages was the elastance (Emax). Conclusions For the first time, the authors have created a visual and quantitative representation of the AHA/ACC stages of LVSD-HF, from normal to end-stage. The study demonstrates that robust, load-independent and reproducible parameters, such as elastance, can be used to categorise and model HF, complementing the existing classification. The modelled PV loops establish previously unknown physiological parameters for each AHA/ACC stage of LVSD-HF, such as LV elastance and highlight that it this parameter alone, in lumped parameter models, that determines the severity of HF. Such information will enable cardiovascular modellers with an interest in HF, to create more accurate models of the heart as it fails.
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Affiliation(s)
- David R. Warriner
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
- Department of Cardiology, Northern General Hospital, Sheffield Teaching Hospitals, Sheffield, S5 7AU, United Kingdom
- * E-mail:
| | - Alistair G. Brown
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Susheel Varma
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Paul J. Sheridan
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
- Department of Cardiology, Northern General Hospital, Sheffield Teaching Hospitals, Sheffield, S5 7AU, United Kingdom
| | - Patricia Lawford
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - David R. Hose
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Abdallah Al-Mohammad
- Department of Cardiology, Northern General Hospital, Sheffield Teaching Hospitals, Sheffield, S5 7AU, United Kingdom
| | - Yubing Shi
- Medical Physics Group, Department of Cardiovascular Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom
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Berthelot E, Bihry N, Brault-Melin O, Assayag P, Cohen-Solal A, Chemla D, Logeart D. Changes in ventricular-arterial coupling during decongestive therapy in acute heart failure. Eur J Clin Invest 2014; 44:982-8. [PMID: 25186206 DOI: 10.1111/eci.12332] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 08/29/2014] [Indexed: 12/20/2022]
Abstract
AIMS Coupled arterial and left ventricular properties are poorly documented in acute heart failure. The aim of this prospective noninvasive study was to document early changes in ventricular-arterial coupling in patients with acutely decompensated HF (ADHF). METHODS AND RESULTS We studied 19 patients hospitalized for ADHF (age 62 ± 15 years, NYHA class 3 or 4). Patients with shock and sustained arrhythmias were excluded. All the patients received intravenous loop diuretics, and none received intravenous vasodilators or inotropes. Ongoing chronic treatments were maintained. Echocardiography and radial artery tonometry were performed simultaneously on admission and after clinical improvement (day 4 ± 1 after admission). Classical echocardiographic parameters were measured, including stroke volume (SV). End-systolic pressure (Pes) was derived from reconstructed central aortic pressure, and arterial elastance (Ea) was calculated as Ea = Pes/SV. End-systolic LV elastance (Ees) was calculated with the single-beat method. Ventricular-arterial coupling was quantified as the Ea/Ees ratio. Following IV diuretic therapy, mean weight loss was 5 ± 2 kg (P < 0·01) and BNP fell from 1813 (median) (IQR = 1284-2342) to 694 (334-1053) pg/mL (P < 0·01). Ea fell by 29%, from 2·46 (2·05-2·86) to 1·78 (1·55-2·00) mmHg/mL (P < 0·01), while Ees remained unchanged (1·28 (1·05-1·52) to 1·13 (0·92-1·34) mmHg/mL). The Ea/Ees ratio therefore fell, from 2·13 (1·70-2·56) to 1·81 (1·56-2·08) (P < 0·02). CONCLUSION An early improvement in ventricular-arterial coupling was observed after diuretic-related decongestive therapy in ADHF patients and was related to a decrease in effective arterial elastance rather than to change in LV contractility.
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17
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Ky B, French B, May Khan A, Plappert T, Wang A, Chirinos JA, Fang JC, Sweitzer NK, Borlaug BA, Kass DA, St John Sutton M, Cappola TP. Ventricular-arterial coupling, remodeling, and prognosis in chronic heart failure. J Am Coll Cardiol 2013; 62:1165-72. [PMID: 23770174 DOI: 10.1016/j.jacc.2013.03.085] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 02/23/2013] [Accepted: 03/13/2013] [Indexed: 12/31/2022]
Abstract
OBJECTIVES The objective of this study was to compare the physiological determinants of ejection fraction (EF)-ventricular size, contractile function, and ventricular-arterial (VA) interaction-and their associations with clinical outcomes in chronic heart failure (HF). BACKGROUND EF is a potent predictor of HF outcomes, but represents a complex summary measure that integrates several components including left ventricular size, contractile function, and VA coupling. The relative importance of each of these parameters in determining prognosis is unknown. METHODS In 466 participants with chronic systolic HF, we derived quantitative echocardiographic measures of EF: cardiac size (end-diastolic volume [EDV]); contractile function (the end-systolic pressure volume relationship slope [Eessb] and intercept [V0]); and VA coupling (arterial elastance [Ea]/Eessb). We determined the association between these parameters and the following adverse outcomes: 1) the combined endpoint of death, cardiac transplantation, or ventricular assist device (VAD) placement; and 2) cardiac hospitalization. RESULTS Over a median follow-up of 3.4 years, there were 76 deaths, 52 transplantations, 14 VAD placements, and 684 cardiac hospitalizations. EF was independently associated with death, transplantation, and VAD placement (adjusted hazard ratio [HR]: 3.0; 95% confidence interval [CI]: 1.8 to 5.0 comparing third and first tertiles), as were EDV (HR: 2.6; 95% CI: 1.5 to 4.2); V0 (HR: 3.6; 95% CI: 2.1 to 6.1); and Ea/Eessb (HR: 2.1; 95% CI: 1.3 to 3.3). EDV, V0, and Ea/Eessb were also associated with risk of cardiac hospitalization. Eessb was not significantly associated with any adverse outcomes in adjusted analyses. CONCLUSIONS Left ventricular size, V0, and VA coupling are associated with prognosis in systolic HF, but end-systolic elastance (Eessb) is not. Assessment of VA coupling via Ea/Eessb is an additional noninvasively derived metric that can be used to gauge prognosis in human HF.
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Affiliation(s)
- Bonnie Ky
- Penn Cardiovascular Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania; Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania.
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Shabanian R, Shahbaznejad L, Razaghian A, Kiani A, Rahimzadeh M, Seifirad S, Kocharian A, Gilani JS, Navabi MA. Sildenafil and ventriculo-arterial coupling in Fontan-palliated patients: a noninvasive echocardiographic assessment. Pediatr Cardiol 2013; 34:129-34. [PMID: 22864675 DOI: 10.1007/s00246-012-0400-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 05/17/2012] [Indexed: 11/29/2022]
Abstract
The fundamental role of pulmonary vascular resistance in the Fontan circulation is obvious. Medications decreasing this resistance may have an impact on the fate of this population. Hence, we assessed noninvasively the effect of oral sildenafil on the ventriculo-arterial coupling in patients with Fontan circulation. In a single-center, prospective case series study, 23 patients with fenestrated extracardiac total cavopulmonary connection age 12-31 years were enrolled in this study. Clinical characteristics and echocardiographic examination were performed before and after a 1 week course of sildenafil at 0.5 mg/kg every 8 h. Sildenafil had no effect on heart rate and blood pressure. However, oxygen saturation was significantly increased with sildenafil (87.6 ± 4.3 vs. 90.1 ± 3.6; P < 0.0001). The calculated noninvasive ventricular end-systolic elastance (Ees) was greater after sildenafil compared with the pre-sildenafil values (1.59 ± 0.17 vs. 1.72 ± 0.27 mm Hg/ml; P = 0.001). Moreover, significant decreases in arterial elastance (Ea) (1.62 ± 0.53 vs. 1.36 ± 0.43 mm Hg/ml; P < 0.0001), ventricular end-diastolic elastance (Eed) (0.05 ± 0.021 vs. 0.04 ± 0.013; P = 0.002), and, finally, ventriculo-arterial coupling index (0.99 ± 0.26 vs. 0.76 ± 0.15; P < 0.0001) were found after sildenafil administration. The intolerable side effects that led to stopping the sildenafil occurred only in one (4 %) patient. Sildenafil has increased ventricular systolic elastance and improved ventriculo-arterial coupling in patients palliated with Fontan circulation. Short-term sildenafil was well tolerated in most of the patients with only minor side effects.
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Affiliation(s)
- Reza Shabanian
- Department of Pediatric Cardiology, Children's Medical Center, Tehran University of Medical Sciences, 14194 Tehran, Iran.
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19
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Wu Y, Ma LX, Niu TW, Meng FL, Cui X, Piao HR. Synthesis and Positive Inotropic Evaluation of (E)-2-(4-Cinnamylpiperazin-1-yl)-N-(1-substituted-4,5-dihydro-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamides. Arch Pharm (Weinheim) 2012; 345:980-8. [DOI: 10.1002/ardp.201200159] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 08/16/2012] [Accepted: 08/17/2012] [Indexed: 11/06/2022]
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20
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Wu Y, Ma LX, Niu TW, Cui X, Piao HR. Synthesis and positive inotropic evaluation of N-(1-oxo-1,2,4,5-tetrahydro-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamides bearing piperazine and 1,4-diazepane moieties. Bioorg Med Chem Lett 2012; 22:4229-32. [DOI: 10.1016/j.bmcl.2012.05.049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 04/19/2012] [Accepted: 05/11/2012] [Indexed: 11/26/2022]
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Raghavan K, Kottam ATG, Valvano JW, Pearce JA. Design of a wireless telemetric backpack device for real-time in vivo measurement of pressure-volume loops in conscious ambulatory rats. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:993-6. [PMID: 19162825 DOI: 10.1109/iembs.2008.4649322] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Pressure - Volume (PV) analysis is the de facto standard for assessing myocardial function. Conductance based methods have been used for the past 27 years to generate instantaneous left ventricular (LV) volume signal. Our research group has developed the instrumentation and the algorithm for obtaining PV loops based on the measurement of real - time admittance magnitude and phase from the LV of anaesthetized mice and rats. In this study, the instrumentation will be integrated into an ASIC (Application Specific Integrated Circuit) and a backpack device will be designed along with this ASIC. This will enable measurement of real-time in vivo P-V loops from conscious and ambulatory rats, useful for both acute and chronic studies.
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Affiliation(s)
- Karthik Raghavan
- Department of Electrical and Computer Engineering, ENS 634-A, C0803, The University of Texas at Austin, Austin, Texas 78712, USA.
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22
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Li JY, Cui X, Liu XK, Hong L, Quan ZS, Piao HR. Synthesis and Positive Inotropic Evaluation of 2-(4-(4-Substituted benzyloxy)-3-methoxybenzyl)-1,4-diazepan-1-yl)-N-(4,5-dihydro-1-methyl[1,2,4]triazolo[4,3-a]quinolin-7-yl)-acetamides. Arch Pharm (Weinheim) 2008; 341:794-9. [DOI: 10.1002/ardp.200800132] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Frenneaux M, Williams L. Ventricular-arterial and ventricular-ventricular interactions and their relevance to diastolic filling. Prog Cardiovasc Dis 2007; 49:252-62. [PMID: 17185113 DOI: 10.1016/j.pcad.2006.08.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chronic heart failure is a common clinical problem, and, until recently, attention has focused predominantly on those patients with reduced left ventricular (LV) systolic function, as evidenced by a reduced LV ejection fraction. However, nearly half of all patients thought clinically to have heart failure have a "preserved" LV ejection fraction, variously defined as greater than 40% to 45% ("heart failure with normal ejection fraction" syndrome). The interaction of the heart with the systemic vasculature, termed ventricular-arterial coupling, is a key determinant of cardiovascular performance. The capacity of the body to augment cardiac output, regulate systemic blood pressure, and respond appropriately to elevations in heart rate and preload depends on both the properties of the heart and the properties of the vasculature into which the heart ejects blood. Although the marked increase of arterial and cardiac stiffness with aging can maintain ventricular-vascular coupling within a normal range, it does have detrimental effects on hemodynamic stability and cardiac reserve. Patients with heart failure with normal ejection fraction have been shown to have both arterial and ventricular stiffening, resulting in enhanced pressure-load dependence and sensitivity of blood pressure to circulating volume and diuretics. There is also indirect evidence to suggest that on exercise, increased external constraint to LV filling (as a result of diastolic ventricular interaction and pericardial constraint) may contribute to impaired use of the Starling mechanism in this group of patients.
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Affiliation(s)
- Michael Frenneaux
- Department of Cardiovascular Medicine, University of Birmingham, Birmingham, United Kingdom
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Tanabe M, Onishi K, Dohi K, Kitamura T, Ito M, Nobori T, Nakano T. Assessment of left ventricular systolic function in patients with chronic atrial fibrillation and dilated cardiomyopathy using the ratio of preceding to prepreceding R–R intervals. Int J Cardiol 2006; 108:197-201. [PMID: 15936095 DOI: 10.1016/j.ijcard.2005.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Revised: 03/25/2005] [Accepted: 05/04/2005] [Indexed: 11/28/2022]
Abstract
The objective of this study was to determine the relation between left ventricular (LV) systolic function and the ratio of preceding (RR1) to prepreceding (RR2) R-R intervals in patients with chronic atrial fibrillation (AF) and dilated cardiomyopathy. LV systolic function (Emax) was examined using a conductance catheter with a micromanometer in 13 patients with chronic AF and dilated cardiomyopathy. We calculated Emax as a load-independent index of LV contractility and compared it with RR1, RR2, and the ratio of RR1/RR2. We analyzed 50+/-13 cardiac cycles (range 18-61) in each patient. Average heart rate was 80+/-13 beats/min, and ejection fraction over all cardiac cycle in each patient measured by conductance catheter was 31+/-8%. Emax was positively correlated with RR1 and RR1/RR2 in all patients, and negatively correlated with RR2 in all patients. In each patient, correlation coefficients of Emax with RR1/RR2 were greater than those with either RR1 or RR2. Furthermore, Emax at RR1/RR2=1 in the linear regression line reflected average Emax over all cardiac cycles in each patient. In conclusion, we have shown that LV contractility correlated positively with RR1/RR2 in patients with chronic AF and dilated cardiomyopathy, and LV contractility at RR1/RR2=1 represents the average value of contractility over all cardiac cycles.
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Affiliation(s)
- Masaki Tanabe
- The First Department of Internal Medicine, Mie University School of Medicine, Tsu, Japan
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25
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Curiel R, Perez-Gonzalez J, Torres E, Landaeta R, Cerrolaza M. Operative contractility: A functional concept of the inotropic state. Clin Exp Pharmacol Physiol 2005; 32:871-81. [PMID: 16173950 DOI: 10.1111/j.1440-1681.2010.04282.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1. Initial unsuccessful attempts to evaluate ventricular function in terms of the 'heart as a pump' led to focusing on the 'heart as a muscle' and to the concept of myocardial contractility. However, no clinically ideal index exists to assess the contractile state. The aim of the present study was to develop a mathematical model to assess cardiac contractility. 2. A tri-axial system was conceived for preload (PL), afterload (AL) and contractility, where stroke volume (SV) was represented as the volume of the tetrahedron. Based on this model, 'operative' contractility ('OperCon') was calculated from the readily measured values of PL, AL and SV. The model was tested retrospectively under a variety of different experimental and clinical conditions, in 71 studies in humans and 29 studies in dogs. A prospective echocardiographic study was performed in 143 consecutive subjects to evaluate the ability of the model to assess contractility when SV and PL were measured volumetrically (mL) or dimensionally (cm). 3. With inotropic interventions, OperCon changes were comparable to those of ejection fraction (EF), velocity of shortening (Vcf) and dP/dt-max. Only with positive inotropic interventions did elastance (Ees) show significantly larger changes. With load manipulations, OperCon showed significantly smaller changes than EF and Ees and comparable changes to Vcf and dP/dt-max. Values of OperCon were similar when AL was represented by systolic blood pressure or wall stress and when volumetric or dimensional values were used. 4. Operative contractility is a reliable, simple and versatile method to assess cardiac contractility.
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Affiliation(s)
- Roberto Curiel
- Centro Medico Docente La Trinidad, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela.
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Dang ABC, Guccione JM, Zhang P, Wallace AW, Gorman RC, Gorman JH, Ratcliffe MB. Effect of ventricular size and patch stiffness in surgical anterior ventricular restoration: a finite element model study. Ann Thorac Surg 2005; 79:185-93. [PMID: 15620941 DOI: 10.1016/j.athoracsur.2004.06.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/04/2004] [Indexed: 11/27/2022]
Abstract
BACKGROUND Surgical anterior ventricular restoration (SAVER) has been proposed for dilated ischemic cardiomyopathy with an akinetic distal anterior left ventricular wall. We tested the hypothesis that SAVER increases stroke volume, reduces mean myofiber stress and achieves optimal results without a patch. METHODS A finite element model of the left ventricle (LV) with an akinetic but contractile anteroapical LV wall segment was used. Separate versions of the model with normal and dilated LV sizes were developed and used to simulate the SAVER operation with and without a patch of varying stiffness from 10 to 100 kilopascals. RESULTS The SAVER operation reduced myofiber stress in the akinetic infarct and infarct borderzone, but caused a reduction in the Starling relationship. In all cases, stroke volume decreased while ejection fraction increased after SAVER. The SAVER operation was more beneficial in dilated ventricles, and the reduction in stroke volume after SAVER without patch was minimal. The effect of patch stiffness was mixed as stiffer material causes a greater reduction in stress yet has the greatest negative effect on stroke volume. CONCLUSIONS These simulations support the use of SAVER in dilated hearts without a patch.
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Affiliation(s)
- Alan B C Dang
- School of Medicine of the University of California, San Francisco, San Francisco, California, USA
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Lehmann A, Boldt J. New pharmacologic approaches for the perioperative treatment of ischemic cardiogenic shock. J Cardiothorac Vasc Anesth 2005; 19:97-108. [PMID: 15747280 DOI: 10.1053/j.jvca.2004.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Andreas Lehmann
- Department of Anesthesiology and Intensive Care Medicine, Klinikum der Stadt Ludwigshafen, Ludwigshafen, Germany
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Fukamachi K, Inoue M, Popović Z, Ootaki Y, Kopcak MW, Dessoffy R, Thomas JD, McCarthy PM. Optimal Mitral Annular and Subvalvular Shape Change Created by the Coapsys Device to Treat Functional Mitral Regurgitation. ASAIO J 2005; 51:17-21. [PMID: 15745128 DOI: 10.1097/01.mat.0000150511.87747.a1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
We have reported that the Myocor Coapsys (Myocor, Inc, Maple Grove, MN) device treated functional mitral regurgitation (MR) by reducing mitral annular dimension and repositioning papillary muscles. This study was conducted to evaluate the optimal Coapsys device sizing level. The Coapsys device was implanted in seven dogs after induction of MR by rapid ventricular pacing. The device consists of anterior and posterior pads connected by a subvalvular cord. The device was tightened in 5% increments of the left ventricular epicardial to epicardial dimension up to 40%. Hemodynamic and echocardiographic measurements were repeated at each tightening level. The Coapsys significantly reduced or eliminated functional MR, and the reduction was maximized at the 30% tightening level or lower in all cases. Although the left ventricular end diastolic volume decreased significantly, forward stroke volume was maintained until the 35% tightening level. The forward ejection fraction significantly increased from 33 +/- 24% at baseline to 62 +/- 42% at 40% tightening level. Mean aortic pressure decreased slightly but significantly. The Coapsys device can be applied over a broad range of tightening levels with significant reduction in MR without negative physiologic impact. This feature makes the device usable [corrected] in a variety of clinical settings.
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Affiliation(s)
- Kiyotaka Fukamachi
- Department of Biomedical Engineering, Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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Nakayama M, Itoh H, Oikawa K, Tajima A, Koike A, Aizawa T, Fu LT, Miyake F. Preload-Adjusted 2 Wave-Intensity Peaks Reflect Simultaneous Assessment of Left Ventricular Contractility and Relaxation. Circ J 2005; 69:683-7. [PMID: 15914946 DOI: 10.1253/circj.69.683] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The magnitudes of the first (WI1) and the second wave-intensity peak (WI2) during the ejection period can be used as indices of left ventricular (LV) contractility and relaxation, respectively. However, use of WI to characterize LV dp/dt and the end-diastolic volume (V ed) relationship may be more problematic, as WI may be affected by changes in preload. METHODS AND RESULTS The LV pressure-volume data sets, consisting of 23 recordings obtained by the conductance method from 12 heart disease patients, were studied. End-systolic elastance (E es) and volume-axis-intercept (V0) were calculated with varying preload. Time constant of LV relaxation (tau), V ed, and WI were calculated from steady-state averaged data. The E es showed a weak correlation with WI1 (r = 0.46, p < 0.05) but a better correlation with preload-adjusted WI1 [WI1/V ed; r=0.86, WI1/V(ed)2; r = 0.92, WI1/(V ed - V0)2; r = 0.89, all p < 0.01]. Similarly, tau did not correlate with WI2 but did correlate with preload-adjusted WI2 [WI2/V ed; r = -0.73, WI2/V(ed) 2; r = -0.63, WI2/(V ed - V0)2; r = -0.78, all p < 0.01]. CONCLUSIONS These data demonstrate the importance of preload-adjustment when using the WI index for simultaneous assessment of LV contractility and relaxation.
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Maurer MS, Spevack D, Burkhoff D, Kronzon I. Diastolic dysfunction: can it be diagnosed by Doppler echocardiography? J Am Coll Cardiol 2004; 44:1543-9. [PMID: 15489083 DOI: 10.1016/j.jacc.2004.07.034] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2003] [Revised: 07/06/2004] [Accepted: 07/12/2004] [Indexed: 11/18/2022]
Abstract
Heart failure with a normal ejection fraction (HFNEF) predominantly afflicts older, female individuals and is considered to be a consequence of diastolic dysfunction. Doppler echocardiography has become the standard method for identifying and characterizing diastolic function. However, the important distinction between Doppler measures of filling dynamics and true indexes of intrinsic ventricular diastolic chamber properties is not widely appreciated. Herein, we delineate physiologic measures of intrinsic ventricular diastolic function, as determined by pressure volume analysis, and compare and contrast these measures with those derived from Doppler echocardiography. Doppler-derived indexes of ventricular filling do not provide specific information on intrinsic passive diastolic properties, and thus, abnormal filling dynamics do not necessarily equate with intrinsic myocardial diastolic dysfunction. This raises a fundamental question as to whether delayed relaxation and/or stiffened passive properties are the unifying pathophysiologic mechanisms in all patients who present with HFNEF.
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Affiliation(s)
- Mathew S Maurer
- Department of Medicine, College of Physicians and Surgeons, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
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Guccione JM, Salahieh A, Moonly SM, Kortsmit J, Wallace AW, Ratcliffe MB. Myosplint decreases wall stress without depressing function in the failing heart: a finite element model study. Ann Thorac Surg 2003; 76:1171-80; discussion 1180. [PMID: 14530007 DOI: 10.1016/s0003-4975(03)00731-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The Myocor Myosplint is a transcavitary tensioning device designed to change left ventricular (LV) shape and reduce wall stress. Regional wall stress cannot be measured in the intact heart and LV function after surgical remodeling is often confounded by inotropic agents and mitral repair. We used a realistic mathematical (finite element) model of the dilated human LV to test the hypothesis that Myosplint decreased regional ventricular fiber stress and improved LV function. METHODS A finite element model was used to simulate the effects of Myosplint on the LV stroke volume/end-diastolic pressure (Starling) relationship and regional distributions of stress in the local muscle fiber direction (fiber stress) for a wide range of diastolic and end-systolic material properties. The nonlinear stress-strain relationship for the diastolic myocardium was anisotropic with respect to the local muscle fiber direction. An elastance model for active fiber stress was incorporated in an axisymmetric geometric model of the globally dilated LV wall. RESULTS Both diastolic compliance and end-systolic elastance shifted to the left on the pressure-volume diagram. LV end-diastolic volume and end-systolic volumes were reduced by 7.6% and 8.6%, respectively. Mean end-diastolic and end-systolic fiber stress was decreased by 24% and 16%, respectively. Although the effect of Myosplint on the Starling relationship was not significant, there were trends toward an improvement in this relationship at low diastolic stiffness, C, high peak intracellular calcium concentration, Ca(0), and high arterial elastance, E(A). Of note, the effect of C was twice that of Ca(0) and E(A). Diastolic function would, therefore, be expected to be the prime determinant of success with Myosplint. CONCLUSIONS Myosplint reduces fiber stress without a decrement in the Starling relationship. Myosplint should be much more effective than partial ventriculectomy as a surgical therapy for patients with dilated cardiomyopathy and end-stage congestive heart failure.
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Affiliation(s)
- Julius M Guccione
- Department of Surgery, School of Medicine, University of California, and San Francisco Veterans Affairs Medical Center, CA 94121, USA.
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Simantirakis EN, Kochiadakis GE, Vardakis KE, Igoumenidis NE, Chrysostomakis SI, Vardas PE. Left ventricular mechanics and myocardial blood flow following restoration of normal activation sequence in paced patients with long-term right ventricular apical stimulation. Chest 2003; 124:233-41. [PMID: 12853528 DOI: 10.1378/chest.124.1.233] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES Asynchronous ventricular activation, as induced by ventricular pacing, is known to affect left ventricular (LV) systolic and diastolic function and myocardial blood flow. However, it is not clear whether the long-term disturbances it causes are reversible after the restoration of the normal ventricular activation sequence. DESIGN In this study, we used the conductance catheter method and a Doppler guidewire to assess the changes in LV mechanics, and correspondingly in myocardial blood flow, after the restoration of the normal ventricular activation sequence in patients with long-term right ventricular apical pacing. PATIENTS Sixteen patients (mean [+/- SD] age, 61 +/- 11 years; 9 men) with right ventricular apical stimulation and complete ventricular pacing capture for a very long period were studied. In eight patients, we analyzed pressure-volume loops before and immediately after the restoration of the normal ventricular activation sequence, and in the remaining eight patients the myocardial blood flow and flow reserve were analyzed. MEASUREMENTS AND RESULTS End-systolic elastance (Ees) [5.503 +/- 0.6 vs 4.287 +/- 0.28 mm Hg/mL, respectively; p = 0.003] and its ratio to effective arterial elastance (1.63 +/- 0.51 vs 2.00 +/- 0.64, respectively; p = 0.009), which are indexes of systolic function and ventriculoarterial coupling, respectively, improved significantly after restoration of the normal ventricular activation sequence. Indexes of diastolic function and the predicted myocardial oxygen consumption (MO(2)) showed no clear change. Coronary flow in the dominant coronary artery increased significantly (46.55 +/- 14.12 vs 71.55 +/- 27.53 mL/min, respectively; p = 0.002), while the coronary flow reserve in the same artery decreased (3.5 +/- 1.0 vs 2.6 +/- 0.5, respectively; p = 0.008). CONCLUSIONS The restoration of a normal activation sequence after long-term ventricular asynchrony enhances acutely contractile function without affecting MO(2). These changes in LV function do not appear to have causal relationships with myocardial blood flow changes.
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Lee WS, Huang WP, Yu WC, Chiou KR, Ding PYA, Chen CH. Estimation of preload recruitable stroke work relationship by a single-beat technique in humans. Am J Physiol Heart Circ Physiol 2003; 284:H744-50. [PMID: 12414443 DOI: 10.1152/ajpheart.00455.2002] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The slope of the preload recruitable stroke work relationship (M(w)) is a highly linear, load-insensitive contractile index. To investigate whether M(w) can be determined from a single steady-state beat, 45 patients were studied during cardiac catheterization. Single-beat M(w) (SBM(w)) was calculated directly from the baseline stroke work and baseline left ventricular (LV) end-diastolic volume (EDV(B)), and the volume-axis intercept (V(w)) was estimated as k x EDV(B) + (k - 1) x LV(wall), where k is the ratio of the epicardial shell volumes corresponding to V(w) and EDV(B) and LV(wall) is the wall volume. The mean of individual k values was 0.72 +/- 0.04, which correlated with LV mass significantly (r = 0.60, P < 0.001). SBM(w) calculated from a constant k of 0.7 predicted M(w) well (r = 0.88, P < 0.0001), and the prediction improved slightly when k was estimated from individual LV mass (r = 0.93, P < 0.0001). Subgroup analyses revealed that the single-beat technique also worked in patients with small or large LV mass or volume or with regional wall motion abnormalities. The absolute change in SBM(w) after dobutamine infusion also correlated with that in M(w). In conclusion, M(w) can be estimated from a steady-state beat without alteration of preload.
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Affiliation(s)
- Wen-Shin Lee
- Division of Cardiology, Taipei Veterans General Hospital, National Yang-Ming University, Taiwan, Republic of China
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Morita S, Ochiai Y, Tanoue Y, Hisahara M, Masuda M, Yasui H. Acute volume reduction with aortic valve replacement immediately improves ventricular mechanics in patients with aortic regurgitation. J Thorac Cardiovasc Surg 2003; 125:283-9. [PMID: 12579096 DOI: 10.1067/mtc.2003.20] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Few data have been available regarding the immediate response in ventricular mechanics to acute volume reduction caused by aortic valve replacement for aortic regurgitation. METHODS We studied 9 patients in the operating room immediately before and after the institution of cardiopulmonary bypass. Left ventricular pressure and cross-sectional area (a surrogate of left ventricular volume) were measured with a catheter-tip manometer and a transesophageal echocardiographic system equipped with automated border-detection technology. Left ventricular pressure-area loops were constructed, and the caval occlusion method was used to obtain the slope of the end-systolic pressure-area relationship and the end-systolic area associated with 100 mm Hg. From the steady-state beats, stroke area was obtained by subtracting the minimum area from the maximum area. Effective arterial elastance, a measure of ventricular afterload, was calculated from end-systolic pressure, and stroke area as follows: effective arterial elastance equals end-systolic pressure divided by stroke area. RESULTS Reductions in maximum area (21.0 +/- 8.5 to 16.0 +/- 6.8 cm(2) [SD])and minimum area (15.3 +/- 8.4 to 12.0 +/- 6.1 m(2)) shifted the baseline pressure-area loops to the left. The slope of the end-systolic pressure-area relationship (11.6 +/- 4.8 to 16.0 +/- 7.5 mm Hg/cm(2)) and afterload (effective arterial elastance, 17.9 +/- 11.6 to 26.3 +/- 16.4 mm Hg/cm(2)) were increased, and the end-systolic area associated with 100 mm Hg was reduced (18.3 +/- 10.0 to 13.7 +/- 5.8 cm(2)). CONCLUSION Correction of volume overload reduced preload (minimum area), shifted the end-systolic pressure-area relationship to the left (decreased end-systolic area), and improved ventricular contractility (increased slope of the end-systolic pressure-area relationship). The result indicated that acute volume reduction favorably influenced ventricular mechanical parameters immediately after the operation.
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Affiliation(s)
- Shigeki Morita
- Department of Cardiovascular Surgery, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
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Bauer F, Jones M, Shiota T, Firstenberg MS, Qin JX, Tsujino H, Kim YJ, Sitges M, Cardon LA, Zetts AD, Thomas JD. Left ventricular outflow tract mean systolic acceleration as a surrogate for the slope of the left ventricular end-systolic pressure-volume relationship. J Am Coll Cardiol 2002; 40:1320-7. [PMID: 12383581 DOI: 10.1016/s0735-1097(02)02138-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE The goal of this study was to analyze left ventricular outflow tract systolic acceleration (LVOT(Acc)) during alterations in left ventricular (LV) contractility and LV filling. BACKGROUND Most indexes described to quantify LV systolic function, such as LV ejection fraction and cardiac output, are dependent on loading conditions. METHODS In 18 sheep (4 normal, 6 with aortic regurgitation, and 8 with old myocardial infarction), blood flow velocities through the LVOT were recorded using conventional pulsed Doppler. The LVOT(Acc) was calculated as the aortic peak velocity divided by the time to peak flow; LVOT(Acc) was compared with LV maximal elastance (E(m)) acquired by conductance catheter under different loading conditions, including volume and pressure overload during an acute coronary occlusion (n = 10). In addition, a clinically validated lumped-parameter numerical model of the cardiovascular system was used to support our findings. RESULTS Left ventricular E(m) and LVOT(Acc) decreased during ischemia (1.67 +/- 0.67 mm Hg.ml(-1) before vs. 0.93 +/- 0.41 mm Hg.ml(-1) during acute coronary occlusion [p < 0.05] and 7.9 +/- 3.1 m.s(-2) before vs. 4.4 +/- 1.0 m.s(-2) during coronary occlusion [p < 0.05], respectively). Left ventricular outflow tract systolic acceleration showed a strong linear correlation with LV E(m) (y = 3.84x + 1.87, r = 0.85, p < 0.001). Similar findings were obtained with the numerical modeling, which demonstrated a strong correlation between predicted and actual LV E(m) (predicted = 0.98 [actual] -0.01, r = 0.86). By analysis of variance, there was no statistically significant difference in LVOT(Acc) under different loading conditions. CONCLUSIONS For a variety of hemodynamic conditions, LVOT(Acc) was linearly related to the LV contractility index LV E(m) and was independent of loading conditions. These findings were consistent with numerical modeling. Thus, this Doppler index may serve as a good noninvasive index of LV contractility.
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Affiliation(s)
- Fabrice Bauer
- Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
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Kondo T, Suzuki Y, Kitano T, Iwai K, Watanabe M, Umehara H, Daido N, Domae N, Tashima M, Uchiyama T, Okazaki T. Vesnarinone causes oxidative damage by inhibiting catalase function through ceramide action in myeloid cell apoptosis. Mol Pharmacol 2002; 61:620-7. [PMID: 11854443 DOI: 10.1124/mol.61.3.620] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vesnarinone is an effective inotropic agent for treating congestive heart failure, but its clinical usage is restricted because of the severe side effect of agranulocytosis. In myeloid HL-60 cells, vesnarinone increased the intracellular content of a proapoptotic lipid mediator, ceramide, in a time- and dose-dependent manner. Vesnarinone-induced apoptosis was significantly enhanced by simultaneous treatment with a cell-permeable N-acetyl sphingosine (C2-ceramide). Treatment with neither vesnarinone, C2-ceramide, nor simultaneously with vesnarinone and C2-ceramide caused a marked increase of reactive oxygen intermediates (ROI) generation measured by the 2',7'-dichlorofluorescin method. However, oxidative damage judged by the production of lipid peroxidates and the nitroblue tetrazolium-reducing ability were enhanced more significantly by simultaneous treatment with vesnarinone and C2-ceramide than by vesnarinone alone. Moreover, vesnarinone inhibited catalase function both at the protein and activity level, and this inhibition was synergistically enhanced by C2-ceramide, and vesnarinone-induced oxidative damage and apoptosis were significantly suppressed by treatment of HL-60 cells with purified catalase. C2-ceramide enhanced vesnarinone-induced inhibition of the ROI-scavenging enzyme catalase at the levels of protein and activity in HL-60 cells; in contrast, however, vesnarinone did not induce ceramide generation, oxidative damage, or catalase depletion in HL-60/ves cells, where vesnarinone could not induce apoptosis. Taken together, the results suggest that vesnarinone induces myeloid cell apoptosis by increasing oxidative damage via ceramide-induced inhibition of catalase function.
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Affiliation(s)
- Tadakazu Kondo
- Department of Hematology and Oncology, Clinical Sciences for Pathological Organs, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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Abstract
The interaction of the heart with the systemic vasculature, termed ventricular-arterial coupling, is a central determinant of net cardiovascular performance. The capacity of the body to augment cardiac output, regulate systemic blood pressure, and respond appropriately to elevations in heart rate and venous filling volume is related as much to the properties of the heart as it is the vasculature into which the heart ejects. With aging, changes in the arterial system associated with vascular stiffening and a reduction in peripheral vasomotor regulation can profoundly affect this coupling by imposing far greater pulsatile and late-systolic loads on the heart. This is accompanied by tandem increases in left ventricular end-systolic stiffness (end-systolic chamber elastance) and reduced diastolic compliance. Altered coupling related to combined ventricular-vascular stiffening increases blood pressure lability for a given change in hemodynamic loading and heart rate (i.e. under stress demands), as well as reduces the capacity to enhance cardiac output without greatly increasing cardiac wall stress. Furthermore, such coupling influences myocardial perfusion by elevating the proportion of coronary flow during the systolic time period. This more closely links ventricular systolic function with myocardial flow, and can compromise flow reserve and exacerbate ischemic dysfunction when ventricular systolic function declines, such as with concomitant heart failure or acute regional ischemia. This article reviews the theory behind ventricular-arterial coupling analysis, the changes in coupling that occur with age and their impact on normal reserve mechanisms, and the likely role of these changes have on heart failure and ischemic heart disease and disease therapy in the elderly.
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Affiliation(s)
- David A Kass
- Division of Cardiology, Department of Medicine, Professor of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21287, USA
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Chen CH, Fetics B, Nevo E, Rochitte CE, Chiou KR, Ding PA, Kawaguchi M, Kass DA. Noninvasive single-beat determination of left ventricular end-systolic elastance in humans. J Am Coll Cardiol 2001; 38:2028-34. [PMID: 11738311 DOI: 10.1016/s0735-1097(01)01651-5] [Citation(s) in RCA: 438] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES The goal of this study was to develop and validate a method to estimate left ventricular end-systolic elastance (E(es)) in humans from noninvasive single-beat parameters. BACKGROUND Left ventricular end-systolic elastance is a major determinant of cardiac systolic function and ventricular-arterial interaction. However, its use in heart failure assessment and management is limited by lack of a simple means to measure it noninvasively. This study presents a new noninvasive method and validates it against invasively measured E(es). METHODS Left ventricular end-systolic elastance was calculated by a modified single-beat method employing systolic (P(s)) and diastolic (P(d)) arm-cuff pressures, echo-Doppler stroke volume (SV), echo-derived ejection fraction (EF) and an estimated normalized ventricular elastance at arterial end-diastole (E(Nd)): E(es(sb)) = [P(d) - (E(Nd(est)) x P(s) x 0.9)[/(E(Nd(est)) x SV). The E(Nd) was estimated from a group-averaged value adjusted for individual contractile/loading effects; E(es(sb)) estimates were compared with invasively measured values in 43 patients with varying cardiovascular disorders, with additional data recorded after inotropic stimulation (n = 18, dobutamine 5 to 10 microg/kg per min). Investigators performing noninvasive analysis were blinded to the invasive results. RESULTS Combined baseline and dobutamine-stimulated E(es) ranged 0.4 to 8.4 mm Hg/ml and was well predicted by E(es(sb)) over the full range: E(es) = 0.86 x E(es(sb)) + 0.40 (r = 0.91, SEE = 0.64, p < 0.00001, n = 72). Absolute change in E(es(sb)) before and after dobutamine also correlated well with invasive measures: E(es(sb)): DeltaE(es) = 0.86 x DeltaE(es(sb)) + 0.67 (r = 0.88, p < 0.00001). Repeated measures of E(es(sb)) over two months in a separate group of patients (n = 7) yielded a coefficient of variation of 20.3 +/- 6%. CONCLUSIONS The E(es) can be reliably estimated from simple noninvasive measurements. This approach should broaden the clinical applicability of this useful parameter for assessing systolic function, therapeutic response and ventricular-arterial interaction.
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Affiliation(s)
- C H Chen
- Division of Cardiology, Taipei Veterans General Hospital, R.O.C., Taipei, Taiwan, Taiwan
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Sugiyama A, Satoh Y, Hashimoto K. Electropharmacologic effects of a new phosphodiesterase III inhibitor, toborinone (OPC-18790), assessed in an in vivo canine model. J Cardiovasc Pharmacol 2001; 38:268-77. [PMID: 11483877 DOI: 10.1097/00005344-200108000-00013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Electropharmacologic effects of a new phosphodiesterase (PDE) III inhibitor toborinone (OPC-18790) were assessed in a halothane-anesthetized, closed-chest canine model. Toborinone, 0.03 mg/kg, increased ventricular contractility, decreased total peripheral resistance, and inhibited intraventricular conduction without changing other cardiovascular parameters. A clinically relevant dose of 0.3 mg/kg increased heart rate, systolic blood pressure, and cardiac output, decreased preload to the left ventricle, enhanced atrioventricular nodal conduction, and shortened repolarization and the vulnerable period of the ventricle, in addition to enhancing the effects observed after the low dose. A high dose of 3 mg/kg of toborinone decreased systolic, mean, and diastolic pressures and prolonged the effective refractory period (ERP) in addition to the effects observed after the middle dose. No further change was detected in ventricular repolarization. Most of the cardiohemodynamic effects can be explained by the PDE III inhibition by toborinone. With regard to electrophysiologic properties, the prolongation of intraventricular conduction time and ERP by toborinone suggests sodium channel inhibition. The lack of the prolongation of ventricular repolarization suggests that previously demonstrated inhibition of I(Kr) and I(K1) and increased I(Ca-L) by toborinone might be counteracted by factors such as the cyclic AMP-dependent outward currents, I(Ks) and I(C1).
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Affiliation(s)
- A Sugiyama
- Department of Pharmacology, Yamanashi Medical University, Japan.
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Abstract
In this article, the author sought to review the two primary components of diastolic function that are most directly and accurately determined using invasive methodologies. For chamber relaxation this is optimally achieved using a micromanometer catheter, whereas for chamber compliance (or its inverse stiffness) this is best achieved by combining this catheter with a measure of instantaneous volume from a conductance catheter, using data from multiple cycles. Even with the ideal data set, the analysis of both properties involves physiologic and often mathematical assumptions, and the extent to which the data do not match these assumptions, the derived indexes may be misleading. Care in the data collection, and awareness of the various factors and pitfalls involved with their analysis can undoubtedly improve the interpretations. As advances in noninvasive methods continue to evolve, reliance on invasive methodologies will continue to fade into the background. At present, however, they remain the gold standard for the two primary diastolic properties described, and have clearly played a central role in the evolution of our understanding of cardiac diastolic disease and its treatment.
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Affiliation(s)
- D A Kass
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
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Ishiki R, Ishihara T, Izawa H, Nagata K, Hirai M, Yokota M. Acute effects of a single low oral dose of pimobendan on left ventricular systolic and diastolic function in patients with congestive heart failure. J Cardiovasc Pharmacol 2000; 35:897-905. [PMID: 10836724 DOI: 10.1097/00005344-200006000-00011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A recent long-term multicenter trial has shown that pimobendan is more effective when administered in low doses. However, no data are available concerning the effect of a low dose of pimobendan on the systolic and diastolic pressure-volume relations in patients with heart failure. Therefore we examined the effects of a single low dose of oral pimobendan, a calcium sensitizer, on systolic and diastolic hemodynamics in patients with cardiomyopathy and congestive heart failure. We measured the left ventricular (LV) pressure-volume relations using a conductance catheter with a micromanometer tip in 10 patients with chronic congestive heart failure resulting from idiopathic cardiomyopathy before and 45 and 90 min after administration of a single oral dose of 2.5 mg of pimobendan. End-systolic elastance was used as an index of LV contractility and was measured during transient occlusion of the inferior vena cava. End-systolic elastance increased significantly by 25% at 45 min (p < 0.05) and by 55% at 90 min (p < 0.01) without an increase in myocardial oxygen consumption. The inotropic effect was accompanied by improved ventriculoarterial coupling. This effect was attenuated in patients with severely impaired myocardial contractility. LV relaxation, assessed by the time constant of isovolumic pressure decay (T(1/2)), was significantly shortened at 90 min (from 47.7 +/- 1.9 to 41.2 +/- 1.7 ms; p < 0.01), although it remained unchanged at 45 min. The diastolic pressure-volume relation showed a leftward and downward shift in all patients. These results indicate that low-dose oral pimobendan had favorable short-term inotropic and lusitropic effects in patients with congestive heart failure caused by idiopathic dilated cardiomyopathy, and may thus be a useful alternative to traditional agents. Further study in a large-scale trial is merited.
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Affiliation(s)
- R Ishiki
- First Department of Internal Medicine, Nagoya University School of Medicine, Japan
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Hare JM, Kass DA, Stamler JS. The physiological response to cardiovascular 'orphan' G protein-coupled receptor agonists. Nat Med 1999; 5:1241-2. [PMID: 10545987 DOI: 10.1038/15193] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cardiac pressor agents typically reduce the amount of blood pumped with each heartbeat. Cardiovascular hemodynamic principles can show whether such a response is physiologic or maladaptive.
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Senzaki H, Fetics B, Chen CH, Kass DA. Comparison of ventricular pressure relaxation assessments in human heart failure: quantitative influence on load and drug sensitivity analysis. J Am Coll Cardiol 1999; 34:1529-36. [PMID: 10551703 DOI: 10.1016/s0735-1097(99)00362-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVES We contrasted various methods for assessing ventricular pressure decay time constants to test whether sensitivity to slight data instability or disparities between model-assumed and real decay are systematically altered by cardiac failure. We hypothesized that such discrepancies could result in apparent increased relaxation sensitivity to load and drug stimulation. BACKGROUND Deviation of relaxation behavior from model-assumed waveforms may be worsened by failure, enhancing instability and apparent load and drug sensitivity of commonly used indexes. METHODS Pressure-volume relations were measured in patients with normal (n = 14), hypertrophic (hypertrophic cardiomyopathy [HCM], n = 15) and dilated-myopathic (dilated cardiomyopathy [DCM], n = 37) hearts before and during preload reduction or inotropic stimulation. Relaxation parameters (monoexponential [ME] model assuming zero-T(in) or non-zero-T(D), T(F) asymptote:, hybrid logistic-T(L), linear-T(LR), and pressure halftime-T(1/2)) were contrasted regarding sensitivity to slight data range manipulation and loading or drug changes. RESULTS In DCM, T(D) and T(F) prolonged 15% to 25% (p < 0.0001) by deletion of only 1-2 data points, whereas this had minimal effect on controls or HCM. This stemmed from systematic deviation of relaxation from an ME decay in DCM. T(1/2) and T(in) were highly sensitive to pure pressure offsets, whereas T(L) was most stable to both manipulations in all hearts. As a result, T(D) and T(F) appeared to be much more sensitive to systolic load in DCM than T(1/2) or T(L) and disproportionately sensitive to increased cyclic adenosine monophosphate (cAMP). CONCLUSIONS Relaxation consistently deviates from an ME decay in DCM resulting in instability and amplified relaxation systolic load or drug dependence of ME-based indexes in failing versus control (or HCM) hearts. The hybrid-logistic method improves quantitative analyses by providing more consistent data fits with all three heart types.
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Affiliation(s)
- H Senzaki
- Department of Internal Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
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Fantini F, Barletta G, Toso A, Baroni M, Di Donato M, Sabatier M, Dor V. Effects of reconstructive surgery for left ventricular anterior aneurysm on ventriculoarterial coupling. Heart 1999; 81:171-6. [PMID: 9922354 PMCID: PMC1728931 DOI: 10.1136/hrt.81.2.171] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To investigate left ventricular elastance (Emax) and effective arterial elastance (Ea) in postinfarction left ventricular aneurysm and evaluate their role in left ventricular function improvement after endoventricular circular patch plasty (EVCPP). Ventriculoarterial coupling has never been studied in these patients. PATIENTS 22 consecutive patients (49 to 73 years) with left ventricular anterior aneurysm. METHODS Haemodynamic studies were done before and two weeks after EVCPP. Ventriculography was performed during atrial pacing (100 beats/min). Pressure/volume loops were analysed and derived parameters measured. Emax was estimated by applying the "single beat" method. Ea was calculated as end systolic pressure/stroke volume. RESULTS Left ventricular volumes and Ea decreased after surgery: end diastolic volume index from mean (SD) 155 (53) to 106 (29); end systolic volume index from 112 (51) to 62 (30) ml/m2 (both p < 0.0001); Ea from 1.65 (0.70) to 1.39 (0.41) mm Hg/ml (p = 0.04). Ejection fraction and Emax increased, without significant changes in stroke volume and work. The decrease in Ea was directly correlated with its preoperative value. The time interval between left ventricular pressure upstroke and peak systolic pressure decreased, from 237 (39) to 191 (41) ms (p < 0.0001), paralleling morphological changes in pressure tracings. CONCLUSIONS After EVCPP, ventriculoarterial coupling improves because of the fall in Ea caused by end systolic pressure reduction. The improvement is related to aortic pressure waveform changes and improved relaxation.
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Affiliation(s)
- F Fantini
- Institute of Internal Medicine and Cardiology, University of Florence, Via delle Masse 125, 50141 Florence, Italy.
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Abstract
Parenterally administered positive inotropic agents remain an important component of the therapeutics of cardiac dysfunction and failure. Dobutamine, a catechol, remains the prototype of this drug group, but recently has been joined by the phosphodiesterase III inhibitor, milrinone. Compared with dobutamine, milrinone has greater vasodilating-unloading properties. The catecholamine, dopamine, is often used as a parenteral positive inotrope; but at moderate to high dose, it evokes considerable systemic vasoconstriction. At lower doses, dopamine appears to augment renal function. Levosimendan and toborinone, new compounds with several mechanisms of action, are under active clinical investigation and review for approval. Parenteral positive inotropic therapy is indicated for short-term (hours to days) treatment of cardiovascular decompensation secondary to ventricular systolic dysfunction, low-output heart failure. More prolonged or continuous infusion of one of these agents may be necessary as a "pharmacologic bridge" to cardiac transplantation, another definitive intervention, or more advanced, intense medical therapy. An occasional patient will require a continuous infusion via indwelling venous catheter and portable pump, simply to be able to be discharged from the hospital setting and function in the home environment. Intermittent parenteral inotropic therapy for chronic heart failure has provoked considerable controversy and passion among cardiologists and heart failure specialists; an attempt is made to present this topic in an objective manner.
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Affiliation(s)
- C V Leier
- Division of Cardiology, The Ohio State University, College of Medicine and Public Health, Columbus, OH 43210, USA
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Ochiai Y, Morita S, Tanoue Y, Kawachi Y, Tominaga R, Yasui H. Effects of amrinone, a phosphodiesterase inhibitor, on right ventricular/arterial coupling immediately after cardiac operations. J Thorac Cardiovasc Surg 1998; 116:139-47. [PMID: 9671908 DOI: 10.1016/s0022-5223(98)70252-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Amrinone, a selective phosphodiesterase III inhibitor, is reported to have a potent inotropic effect on the left ventricle, but the effects of this drug on right ventricular contractility in the clinical setting are unknown. The concept of ventricular/arterial coupling was applied to investigate the effects of amrinone on right ventricular contractility and afterload with transesophageal echocardiography. METHODS AND RESULTS The study was performed in the intensive care unit with 11 patients who had undergone cardiac operations. Right ventricular cross-sectional area was measured with transesophageal echocardiography equipped with a capability of automated border detection as a surrogate for right ventricular volume. Multiple pressure-area loops were obtained by reducing preload to measure end-systolic elastance and effective arterial elastance. External work and pressure-volume area were also measured to calculate the efficiency of energy transfer from pressure-volume area to external work. Nitroprusside (0.3 to 0.5 microg x kg(-1) x min(-1)) and amrinone (1 mg x kg(-1) intravenously followed by 10 microg x kg(-1) x min(-1)) were administered. With nitroprusside infusion, end-systolic elastance and effective arterial elastance remained unchanged (end-systolic elastance, 4.73 +/- 2.18 mm Hg/cm2 to 4.65 +/- 2.09 mm Hg/cm2; effective arterial elastance, 8.05 +/- 3.84 mm Hg/cm2 to 7.70 +/- 3.64 mm Hg/cm2). In contrast, amrinone reduced afterload (effective arterial elastance, 8.82 +/- 3.99 mm Hg/cm2 to 7.05 +/- 4.01 mm Hg/cm2, p = 0.004) and enhanced contractility (end-systolic elastance, 4.47 +/- 1.79 mm Hg/cm2 to 6.56 +/- 2.22 mm Hg/cm2, p = 0.007). Consequently, amrinone decreased the ventricular/arterial coupling ratio (effective arterial elastance/end-systolic elastance, 2.40 +/- 1.45 to 1.16 +/- 0.63, p = 0.009) and improved the efficiency of energy transfer (external work/pressure-volume area, 0.44 +/- 0.15 to 0.54 +/- 0.15, p = 0.013). CONCLUSIONS Right ventricular pressure-area relations obtained with transesophageal echocardiography could successfully separate the simultaneous change in right ventricular systolic mechanics and afterload caused by amrinone. Amrinone caused enhancement of right ventricular contractility and afterload reduction.
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Affiliation(s)
- Y Ochiai
- Department of Cardiovascular Surgery, Faculty of Medicine, Kyushu University, Fukuoka, Japan
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47
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MacGowan GA, Haber HL, Cowart TD, Tedesco C, Wu C, Feldman MD. Direct myocardial effects of OPC-18790 in human heart failure: beneficial effects on contractile and diastolic function demonstrated by intracoronary infusion with pressure-volume analysis. J Am Coll Cardiol 1998; 31:1344-51. [PMID: 9581731 DOI: 10.1016/s0735-1097(98)00105-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES We sought to determine the precise myocardial effects of OPC-18790 as demonstrated by intracoronary administration. BACKGROUND Although previous studies have determined the cardiovascular effects of a novel intravenous inotrope, OPC-18790, the observed benefits on contractile and diastolic function may have been confounded by the marked changes in peripheral loading associated with this drug when given intravenously. METHODS Eight heart failure patients received intracoronary OPC-18790 at 31.25 microg/min for 20 min, and then at 62.5 microg/min for another 20 min. Hemodynamic variables and pressure-volume indexes using the conductance catheter method were determined at baseline and then after the two doses. RESULTS There were no significant effects on heart rate, cardiac output or loading conditions, including afterload as determined by systemic vascular resistance and arterial elastance (Ea) and preload as determined by end-diastolic volume (EDV). There were significant increases in end-systolic elastance (Ees) from 0.74+/-0.11 to 0.90+/-0.16 mm Hg/ml at 31.25 microg/min and to 137+/-0.33 mm Hg/ml at 62.5 microg/min (p < 0.05 by analysis of variance [ANOVA]). Diastolic function improved, as determined by the time constant for isovolumetric relaxation tau, which decreased significantly from baseline to 31.25 microg/min (94+/-9 to 79+/-9 ms, p < 0.05), and did not shorten further at 62.5 microg/min (78+/-8 ms, p=NS). There were significant decreases in right atrial pressure (9+/-1 to 7+/-1 mm Hg, p < 0.01 by ANOVA) and mean pulmonary artery wedge pressure (21+/-3 to 16+/-2 mm Hg, p < 0.05 by ANOVA). This fall in filling pressures was not accompanied by any change in EDV. Inspection of the diastolic portion of the pressure-volume curve confirmed a downward shift consistent with pericardial release in five of the eight patients. CONCLUSIONS Intracoronary administration of OPC-18790 demonstrates that the direct myocardial effects of this agent include a modest increase in inotropy and improvement in diastolic function, both of which occur without increases in heart rate, indicating that this agent may be beneficial for the intravenous treatment of congestive heart failure.
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Affiliation(s)
- G A MacGowan
- Division of Cardiology, University of Pittsburgh Medical Center, Pennsylvania 15213, USA
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Dernellis JM, Stefanadis CI, Zacharoulis AA, Toutouzas PK. Left atrial mechanical adaptation to long-standing hemodynamic loads based on pressure-volume relations. Am J Cardiol 1998; 81:1138-43. [PMID: 9605056 DOI: 10.1016/s0002-9149(98)00134-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Left atrial (LA) adaptation during the development of left ventricular (LV) dysfunction is not fully understood. We performed echocardiographic assessment of LA volumes simultaneously with recordings of pulmonary wedge pressures in 60 patients. Twenty patients had no structural or functional LV abnormalities, 20 had a recent myocardial infarction with LV dysfunction, and 20 suffered from congestive heart failure (CHF). Pressure-volume loops were obtained at baseline and during increases in LA pressure produced by normal saline infusion. LA afterload was estimated by the effective LV elastance (E(LV)). Atrioventricular coupling was calculated by the E(LV)/E(es) ratio (where E(es) is the end-systolic elastance). E(es) increased in patients with myocardial infarction (0.80 +/- 0.09 mm Hg/ml, p <0.001), whereas it decreased in patients with CHF (0.22 +/- 0.05 mm Hg/ml, p <0.001) compared with controls (0.61 +/- 0.07 mm Hg/ml). Similarly, stroke workload increased in patients with myocardial infarction (60.7 +/- 7.3 mm Hg x ml, p <0.001), whereas it decreased in patients with CHF (25.4 +/- 2.2 mm Hg x ml, p <0.001) compared with controls (44.8 +/- 5.5 mm Hg x ml). In all patients LA stiffness (slope of the relation of the filling portion of the pressure-volume loop) was increased compared with controls (controls: 0.13 +/- 0.04, patients with myocardial infarction: 0.22 +/- 0.05, and patients with CHF: 0.27 +/- 0.05 mm Hg/ml, p <0.001 for both comparisons). Moreover, the E(LV)/E(es) ratio increased gradually as LV function deteriorated (controls: 1.06 +/- 0.10, patients with myocardial infarction: 1.35 +/- 0.16, and patients with CHF: 6.90 +/- 0.84, p <0.001). Thus, early in heart failure, LA pump function is augmented but LA stiffness increases and work mismatch occurs. With further progression of LV dysfunction, LA pump function decreases as a result of increased afterload imposed on the LA myocardium.
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Affiliation(s)
- J M Dernellis
- First Cardiology Department, Amalia Fleming Hospital, University of Athens, Greece
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49
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Chen CH, Nevo E, Fetics B, Nakayama M, Pak PH, Maughan WL, Kass DA. Comparison of continuous left ventricular volumes by transthoracic two-dimensional digital echo quantification with simultaneous conductance catheter measurements in patients with cardiac diseases. Am J Cardiol 1997; 80:756-61. [PMID: 9315583 DOI: 10.1016/s0002-9149(97)00509-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Automated border detection enables real-time tracking of left ventricular (LV) volume by 2-dimensional transthoracic echocardiography. This technique has not been previously compared with simultaneously measured continuous LV volumes at rest or during transients in humans. We performed 18 studies in 16 patients (age 50 +/- 15 years, range 22 to 70; ejection fraction 63 +/- 20%, range 15% to 85%) in which continuous LV volumes acquired by digital echo quantification (DEQ) were compared with simultaneous conductance catheter volume obtained by cardiac catheterization. Both volume signals were calibrated by thermodilution-derived cardiac output and ventriculogram-derived ejection fraction. Volume traces acquired at rest were averaged to generate a comparison cycle. The averaged volume waveforms acquired by DEQ and by conductance catheter were similar during all phases of the cardiac cycle and significantly correlated (conductance catheter = slope. DEQ + intercept, slope = 0.94 +/- 0.09, intercept = 5 +/- 8 ml, r2 = 0.86 +/- 0.12, all p <0.0001). Steady-state hemodynamic parameters calculated using either averaged volume signal were significantly correlated. Transient obstruction of the inferior vena cava yielded a 45 +/- 13% decrease in end-diastolic volume. Successful recordings of DEQ volume during preload reduction were obtained in only 50% of studies. End-diastolic volumes from the 2 methods were significantly correlated (mean slope 0.88 +/- 0.31, mean intercept 14 +/- 37 ml, average r2 = 0.89 +/- 0.11, all p <0.01), as were end-systolic volumes: mean slope 0.80 +/- 0.43, intercept = -20 +/- 26 ml, r2 = 0.67 +/- 0.18, all p <0.05). We conclude that automated border detection technique by DEQ is reliable for noninvasive, transthoracic, continuous tracking of LV volumes at steady state, but has limitations in use during preload reduction maneuvers in humans.
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Affiliation(s)
- C H Chen
- Department of Internal Medicine, Johns Hopkins University Medical Institutions, Baltimore, Maryland, USA
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50
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Wu CC, Skalak TC, Schwenk TR, Mahler CM, Anne A, Finnerty PW, Haber HL, Weikle RM, Feldman MD. Accuracy of the conductance catheter for measurement of ventricular volumes seen clinically: effects of electric field homogeneity and parallel conductance. IEEE Trans Biomed Eng 1997; 44:266-77. [PMID: 9125809 DOI: 10.1109/10.563296] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The conductance-volume method is an important clinical tool which allows the assessment of left ventricular function in vivo. However, the accuracy of this method is limited by the homogeneity of electric field the conductance catheter produces and the parallel conductance of surrounding structures. This paper examines these sources of error in volumes seen clinically. The characteristics of electric field within a chamber were examined using computer simulation. Nonconductive and conductive models were constructed and experimental measurements obtained using both single-field (SF) and dual-field (DF) excitation. Results from computer simulations and in vitro measurements were compared to validate the purposed theoretical model of conductance-volume method. The effects of field homogeneity and significance of parallel conductance in volume measurement were then determined. The results of this study show that DF provide a more accurate measure of intraventricular volume than SF, especially at larger volumes. However, both significantly underestimate true volume at larger volumes. In addition, the parallel conductance due to the chamber wall is significant at small volumes, but diminishes at larger volumes. Furthermore, the effect of parallel conductance beyond the chamber wall may be negligible. This study demonstrates the limitations in applying current conductance technology to patients with dilated hearts.
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Affiliation(s)
- C C Wu
- Division of Cardiology, School of Medicine, University of Pittsburgh, PA 15213, USA.
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