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Liang D, Zhou L, Zhou H, Zhang F, Fang G, Leng J, Wu Y, Zhang Y, Yang A, Liu Y, Chen YH. A GABAergic system in atrioventricular node pacemaker cells controls electrical conduction between the atria and ventricles. Cell Res 2024; 34:556-571. [PMID: 38849501 DOI: 10.1038/s41422-024-00980-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 05/13/2024] [Indexed: 06/09/2024] Open
Abstract
Physiologically, the atria contract first, followed by the ventricles, which is the prerequisite for normal blood circulation. The above phenomenon of atrioventricular sequential contraction results from the characteristically slow conduction of electrical excitation of the atrioventricular node (AVN) between the atria and the ventricles. However, it is not clear what controls the conduction of electrical excitation within AVNs. Here, we find that AVN pacemaker cells (AVNPCs) possess an intact intrinsic GABAergic system, which plays a key role in electrical conduction from the atria to the ventricles. First, along with the discovery of abundant GABA-containing vesicles under the surface membranes of AVNPCs, key elements of the GABAergic system, including GABA metabolic enzymes, GABA receptors, and GABA transporters, were identified in AVNPCs. Second, GABA synchronously elicited GABA-gated currents in AVNPCs, which significantly weakened the excitability of AVNPCs. Third, the key molecular elements of the GABAergic system markedly modulated the conductivity of electrical excitation in the AVN. Fourth, GABAA receptor deficiency in AVNPCs accelerated atrioventricular conduction, which impaired the AVN's protective potential against rapid ventricular frequency responses, increased susceptibility to lethal ventricular arrhythmias, and decreased the cardiac contractile function. Finally, interventions targeting the GABAergic system effectively prevented the occurrence and development of atrioventricular block. In summary, the endogenous GABAergic system in AVNPCs determines the slow conduction of electrical excitation within AVNs, thereby ensuring sequential atrioventricular contraction. The endogenous GABAergic system shows promise as a novel intervention target for cardiac arrhythmias.
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Affiliation(s)
- Dandan Liang
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Research Units of Origin and Regulation of Heart Rhythm, Chinese Academy of Medical Sciences, Shanghai, China
- Clinical Center for Heart Disease Research, Tongji University, Shanghai, China
| | - Liping Zhou
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Huixing Zhou
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Fulei Zhang
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Guojian Fang
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Junwei Leng
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yahan Wu
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yuemei Zhang
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Anqi Yang
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yi Liu
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yi-Han Chen
- State Key Laboratory of Cardiovascular Diseases, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
- Shanghai Arrhythmia Research Center, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
- Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
- Research Units of Origin and Regulation of Heart Rhythm, Chinese Academy of Medical Sciences, Shanghai, China.
- Clinical Center for Heart Disease Research, Tongji University, Shanghai, China.
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Bank AJ, Brown CD, Burns KV, Johnson KM. Determination of sensed and paced atrial-ventricular delay in cardiac resynchronization therapy. Pacing Clin Electrophysiol 2024; 47:533-541. [PMID: 38477034 DOI: 10.1111/pace.14963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 02/08/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024]
Abstract
BACKGROUND Optimization of atrial-ventricular delay (AVD) during atrial sensing (SAVD) and pacing (PAVD) provides the most effective cardiac resynchronization therapy (CRT). We demonstrate a novel electrocardiographic methodology for quantifying electrical synchrony and optimizing SAVD/PAVD. METHODS We studied 40 CRT patients with LV activation delay. Atrial-sensed to RV-sensed (As-RVs) and atrial-paced to RV-sensed (Ap-RVs) intervals were measured from intracardiac electrograms (IEGM). LV-only pacing was performed over a range of SAVD/PAVD settings. Electrical dyssynchrony (cardiac resynchronization index; CRI) was measured at each setting using a multilead ECG system placed over the anterior and posterior torso. Biventricular pacing, which included multiple interventricular delays, was also conducted in a subset of 10 patients. RESULTS When paced LV-only, peak CRI was similar (93 ± 5% vs. 92 ± 5%) during atrial sensing or pacing but optimal PAVD was 61 ± 31 ms greater than optimal SAVD. The difference between As-RVs and Ap-RVs intervals on IEGMs (62 ± 31 ms) was nearly identical. The slope of the correlation line (0.98) and the correlation coefficient r (0.99) comparing the 2 methods of assessing SAVD-PAVD offset were nearly 1 and the y-intercept (0.63 ms) was near 0. During simultaneous biventricular (BiV) pacing at short AVD, SAVD and PAVD programming did not affect CRI, but CRI was significantly (p < .05) lower during atrial sensing at long AVD. CONCLUSIONS A novel methodology for measuring electrical dyssynchrony was used to determine electrically optimal SAVD/PAVD during LV-only pacing. When BiV pacing, shorter AVDs produce better electrical synchrony.
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Affiliation(s)
- Alan J Bank
- Research Department, Minneapolis Heart Institute East at United Hospital, St. Paul, Minnesota, USA
- Heart Rhythm Science Center, Minneapolis Heart Institute Foundation, Minneapolis, Minnesota, USA
| | - Christopher D Brown
- Research Department, Minneapolis Heart Institute East at United Hospital, St. Paul, Minnesota, USA
| | - Kevin V Burns
- Research Department, Minneapolis Heart Institute East at United Hospital, St. Paul, Minnesota, USA
- Heart Rhythm Science Center, Minneapolis Heart Institute Foundation, Minneapolis, Minnesota, USA
| | - Katie M Johnson
- Research Department, Minneapolis Heart Institute East at United Hospital, St. Paul, Minnesota, USA
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Green PG, Monteiro C, Holdsworth DA, Betts TR, Herring N. Cardiac resynchronization using fusion pacing during exercise. J Cardiovasc Electrophysiol 2024; 35:146-154. [PMID: 37888415 DOI: 10.1111/jce.16120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/02/2023] [Accepted: 10/24/2023] [Indexed: 10/28/2023]
Abstract
INTRODUCTION Fusion pacing requires correct timing of left ventricular pacing to right ventricular activation, although it is unclear whether this is maintained when atrioventricular (AV) conduction changes during exercise. We used cardiopulmonary exercise testing (CPET) to compare cardiac resynchronization therapy (CRT) using fusion pacing or fixed AV delays (AVD). METHODS Patients 6 months post-CRT implant with PR intervals < 250 ms performed two CPET tests, using either the SyncAV™ algorithm or fixed AVD of 120 ms in a double-blinded, randomized, crossover study. All other programming was optimized to produce the narrowest QRS duration (QRSd) possible. RESULTS Twenty patients (11 male, age 71 [65-77] years) were recruited. Fixed AVD and fusion programming resulted in similar narrowing of QRSd from intrinsic rhythm at rest (p = .85). Overall, there was no difference in peak oxygen consumption (V̇O2 PEAK , p = .19), oxygen consumption at anaerobic threshold (VT1, p = .42), or in the time to reach either V̇O2 PEAK (p = .81) or VT1 (p = .39). The BORG rating of perceived exertion was similar between groups. CPET performance was also analyzed comparing whichever programming gave the narrowest QRSd at rest (119 [96-136] vs. 134 [119-142] ms, p < .01). QRSd during exercise (p = .03), peak O2 pulse (mL/beat, a surrogate of stroke volume, p = .03), and cardiac efficiency (watts/mL/kg/min, p = .04) were significantly improved. CONCLUSION Fusion pacing is maintained during exercise without impairing exercise capacity compared with fixed AVD. However, using whichever algorithm gives the narrowest QRSd at rest is associated with a narrower QRSd during exercise, higher peak stroke volume, and improved cardiac efficiency.
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Affiliation(s)
- Peregrine G Green
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, UK
- Department of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Oxford Heart Centre, John Radcliffe Hospital, University of Oxford NHS Foundation Trust, Oxford, UK
| | - Cristiana Monteiro
- Department of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - David A Holdsworth
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, UK
- Oxford Heart Centre, John Radcliffe Hospital, University of Oxford NHS Foundation Trust, Oxford, UK
| | - Timothy R Betts
- Department of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Oxford Heart Centre, John Radcliffe Hospital, University of Oxford NHS Foundation Trust, Oxford, UK
| | - Neil Herring
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, UK
- Oxford Heart Centre, John Radcliffe Hospital, University of Oxford NHS Foundation Trust, Oxford, UK
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Akhtar Z, Gallagher MM, Kontogiannis C, Leung LWM, Spartalis M, Jouhra F, Sohal M, Shanmugam N. Progress in Cardiac Resynchronisation Therapy and Optimisation. J Cardiovasc Dev Dis 2023; 10:428. [PMID: 37887875 PMCID: PMC10607614 DOI: 10.3390/jcdd10100428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 10/06/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
Cardiac resynchronisation therapy (CRT) has become the cornerstone of heart failure (HF) treatment. Despite the obvious benefit from this therapy, an estimated 30% of CRT patients do not respond ("non-responders"). The cause of "non-response" is multi-factorial and includes suboptimal device settings. To optimise CRT settings, echocardiography has been considered the gold standard but has limitations: it is user dependent and consumes time and resources. CRT proprietary algorithms have been developed to perform device optimisation efficiently and with limited resources. In this review, we discuss CRT optimisation including the various adopted proprietary algorithms and conduction system pacing.
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Affiliation(s)
- Zaki Akhtar
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Mark M. Gallagher
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Christos Kontogiannis
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Lisa W. M. Leung
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Michael Spartalis
- Department of Cardiology, National and Kapodistrian University of Athens, 10679 Athens, Greece
| | - Fadi Jouhra
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Manav Sohal
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
| | - Nesan Shanmugam
- Department of Cardiology, St George’s University Hospital, Blackshaw Road, London SW17 0QT, UK
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Keene D, Miyazawa AA, Johal M, Arnold AD, Ali N, Saqi KA, March K, Burden L, Francis DP, Whinnett ZI, Shun‐Shin MJ. Optimizing atrio-ventricular delay in pacemakers using potentially implantable physiological biomarkers. Pacing Clin Electrophysiol 2022; 45:461-470. [PMID: 34967945 PMCID: PMC9305784 DOI: 10.1111/pace.14434] [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] [Received: 10/12/2021] [Revised: 11/25/2021] [Accepted: 12/19/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hemodynamically optimal atrioventricular (AV) delay can be derived by echocardiography or beat-by-beat blood pressure (BP) measurements, but analysis is labor intensive. Laser Doppler perfusion monitoring measures blood flow and can be incorporated into future implantable cardiac devices. We assess whether laser Doppler can be used instead of BP to optimize AV delay. METHODS Fifty eight patients underwent 94 AV delay optimizations with biventricular or His-bundle pacing using laser Doppler and simultaneous noninvasive beat-by-beat BP. Optimal AV delay was defined using a curve of hemodynamic response to switching from AAI (reference state) to DDD (test state) at several AV delays (40-320 ms), with automatic quality control checking precision of the optimum. Five subsequent patients underwent an extended protocol to test the impact of greater numbers of alternations on optimization quality. RESULTS 55/94 optimizations passed quality control resulting in an optimal AV delay on laser Doppler similar to that derived by BP (median absolute deviation 12 ms). An extended protocol with increasing number of replicates consistently improved quality and reduced disagreement between laser Doppler and BP optima. With only five replicates, no optimization passed quality control, and the median absolute deviation would be 29 ms. These improved progressively until at 50 replicates, all optimizations passed quality control and the median absolute deviation was only 13 ms. CONCLUSIONS Laser Doppler perfusion produces hemodynamic optima equivalent to BP. Quality control can be automatic. Adding more replicates, consistently improves quality. Future implantable devices could use such methods to dynamically and reliably optimize AV delays.
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Affiliation(s)
- Daniel Keene
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Alejandra A Miyazawa
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Monika Johal
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Ahran D Arnold
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Nadine Ali
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Khulat A Saqi
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Katherine March
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Leah Burden
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK
| | - Darrel P Francis
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Zachary I Whinnett
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
| | - Matthew J Shun‐Shin
- National Heart and Lung Institute, Imperial College London, Hammersmith HospitalLondonUK,Imperial College Healthcare NHS Trust, Hammersmith HospitalLondonUK
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Viskin D, Halkin A, Sherez J, Megidish R, Fourey D, Keren G, Topilsky Y. Heart Failure due to High Degree Atrio-Ventricular Block: How Frequent is it and what is the cause? Can J Cardiol 2021; 37:1562-1568. [PMID: 34029699 DOI: 10.1016/j.cjca.2021.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/13/2021] [Accepted: 05/16/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The causes of heart failure (HF) during high-grade atrio-ventricular block (AVB) are poorly understood. This study assessed the mechanisms of HF in patients with AVB. METHODS We studied patients presenting (over the period 2012-2016) with high-grade AVB not related to acute myocardial infarction (MI). Patients with preexisting significant valvular heart disease were excluded. All patients underwent comprehensive echocardiographic evaluation during AVB, prior to pacemaker implantation. The diagnosis of HF was based on the Framingham criteria. RESULTS 122 patients were included in the study, 50% male, average age 76+/-13 years. Twenty-eight (23%) patients with AVB presented with HF. Univariate correlates associated with HF were decrease in cardiac output (CO) [0.67 (95% confidence interval 0.49-0.9) per liter/min, p=0.007], measures of impaired left ventricular (LV) compliance and increase in diastolic mitral regurgitation (MR) volume [1.04 (1.01- 1.07), per cc, p=0.0016]. Ventricular rate during AVB and left-ventricular ejection fraction (LVEF) were not significantly associated with the presence of HF. By multivariate nominal logistic analysis, the best model associated with HF included diastolic MR volume [OR 1.03 (1.00-1.07), p=0.03], A-wave deceleration time [OR 0.96 (0.94-0.98), p=0.001], and CO [OR 0.72 (0.48-1.00), p=0.05], (X2= 30.6; AUC 0.84; p<0.0001 for the entire model). CONCLUSIONS In the setting of high-degree AVB, clinical HF occurrence correlates with impaired LV compliance and diastolic MR volume, but not with heart rate or LVEF. The cardiac performance of patients with poor LV compliance and high-volume diastolic MR may show maladjustment to slow heart rates, manifesting as low CO and HF.
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Affiliation(s)
- Dana Viskin
- Sackler School of Medicine, Tel Aviv University
| | - Amir Halkin
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel
| | - Jack Sherez
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel
| | - Ricki Megidish
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel
| | - Dana Fourey
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel
| | - Gad Keren
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel
| | - Yan Topilsky
- the Department of Cardiology, Tel Aviv Sourasky Medical Center and, Sackler School of Medicine, Tel Aviv University, Israel.
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Yenerçağ M, Yüksel S, Çoksevim M, Akçay M, Arslan U. Noninvasive cardiac output measurement based optimization in nonresponders of cardiac resynchronization therapy. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2020; 43:394-401. [PMID: 32198929 DOI: 10.1111/pace.13904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/03/2020] [Accepted: 03/15/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND Cardiac resynchronization therapy (CRT) is an important and effective therapy for end-stage heart failure (HF). Nonresponse to CRT is one of the main obstacles to its application in clinical practice. Herein, we investigated the utilization of the optimization technique using noninvasive cardiac output measurement (NICOM) based Mobil-O-Graph device that measures several circulation parameters noninvasively. METHODS Seventy-five CRT nonresponder HF patients with an implanted CRT device were included. Patients were randomized equally to 3 groups: NICOM, echocardiographic, and empirical optimization groups. After 3 months of optimization, changes in six minutes walk test (6-MWT), cardiac output (CO), left ventricular ejection fraction (LVEF), and end-systolic volume (LVESV) were measured. New York Heart Association (NYHA) class and hospitalization for HF were also determined. RESULTS There were no statistically significant differences among the three groups in terms of demographics, baseline characteristics. In the NICOM group, the 6-MWT, LVEF, CO, and LVESV measurements showed significant improvements compared to baseline values (P < .05). There was no significant improvement in 6-MWT, LVEF, CO, NYHA class, and LVESV in Echo and Empirical groups after 3 months (P > .05). 6-MWT, CO, LVESV percentages, and hospitalization for HF were significantly different between the groups (P < .05). In post hoc analyzes, the percentages of the change in 6-MWT, CO, LVESV, and hospitalization for HF were significantly higher in the NICOM group (P < .017). CONCLUSIONS This study suggests that Mobil-O-Graph device optimization according to CO measures does appear to have potential hemodynamic and clinical benefits in nonresponder CRT patients. Use of Mobil-O-Graph device as an option for optimization of CRT devices can be an attractive method of improving CRT outcomes.
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Affiliation(s)
- Mustafa Yenerçağ
- Department of Cardiology, University of Health Sciences, Samsun Training and Research Hospital, Samsun, Turkey
| | - Serkan Yüksel
- Department of Cardiology, Ondokuz Mayıs University Hospital, Samsun, Turkey
| | - Metin Çoksevim
- Department of Cardiology, Ondokuz Mayıs University Hospital, Samsun, Turkey
| | - Murat Akçay
- Department of Cardiology, Ondokuz Mayıs University Hospital, Samsun, Turkey
| | - Uğur Arslan
- Department of Cardiology, University of Health Sciences, Samsun Training and Research Hospital, Samsun, Turkey
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Automatic Continuous CRT Optimization to Improve Hemodynamic Response: An Italian Single-Center Experience. Int J Vasc Med 2020. [DOI: 10.1155/2020/7942381] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background. Optimization of cardiac resynchronization therapy (CRT) settings after implant can improve response to therapy. In this Italian single-center experience, we investigated the rate of hemodynamic and clinical response in heart failure patients treated with continuously and automatically optimized CRT. Methods. Patients were selected from June 2015 to April 2017 according to the most recent CRT guidelines; all were in sinus rhythm at implant and received a CRT-defibrillator system equipped with SonR, which automatically optimizes AV and VV delays every week. SonR was activated just after implant and remained active during follow-up. The rate of hemodynamic response (R-HR) was defined as ΔLVEF>5%, super-response (R-HSR) as ΔLVEF>15%, and clinical response as a negative transition of NYHA class≥−1 at 6 months follow-up vs. baseline (preimplant). Results. Mean follow-up for the 31 patients (aged 69.9±9.4 years; 61% male; NYHA class II/III 19%/81%; ischemic etiology 65%) was 6±0.7 months. At baseline, LVEF was 29.1%±4.7% and QRS duration 146±13 ms. LBBB morphology was observed in 65%. At 6 months, R-HR was 74% (23/31), R-HSR 32% (10/31), and clinical response rate 77% (24/31). Hemodynamically, patients with ischemic etiology benefited more than those without ischemic etiology, both in terms of response (80% versus 64%) and super-response (35% versus 27%). Conclusions. Continuous automatic weekly optimization of CRT over 6 months consistently improved R-HR, R-HSR, and clinical response in NYHA class II/III heart failure patients versus baseline. Patients with ischemic etiology in particular may benefit hemodynamically from this type of CRT optimization.
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Korach R, Kahr PC, Ruschitzka F, Steffel J, Flammer AJ, Winnik S. Long-term follow-up after cardiac resynchronization therapy-optimization in a real-world setting: A single-center cohort study. Cardiol J 2020; 28:728-737. [PMID: 31960943 DOI: 10.5603/cj.a2020.0004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 11/15/2019] [Accepted: 01/01/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Suboptimal device programming is among the reasons for reduced response to cardiac resynchronization therapy (CRT). However, whether systematic optimization is beneficial remains unclear, particularly late after CRT implantation. The aim of this single-center cohort study was to assess the effect of systematic atrioventricular delay (AVD) optimization on echocardiographic and device parameters. METHODS Patients undergoing CRT optimization at the University Hospital Zurich between March 2011 and January 2013, for whom a follow-up was available, were included. AVD optimization was based on 12-lead electrocardiography (ECG) and echocardiographic left ventricular inflow characteristics. Parameters were assessed at the time of CRT optimization and follow-up, and were compared between patients with AVD optimization (intervention group) and those for whom no AVD optimization was deemed necessary (control group). RESULTS Eighty-one patients with a mean age of 64 ± 11 years were included in the analysis. In 73% of patients, AVD was deemed suboptimal and was changed accordingly. After a median follow-up time of 10.4 (IQR 6.2 to 13.2) months, the proportion of patients with sufficient biventricular pacing (> 97% pacing) was greater in the intervention group (78%) compared to controls (50%). Furthermore, AVD adaptation was associated with an improvement in interventricular mechanical delay (decrease of 6.6 ± 26.2 ms vs. increase of 4.3 ± 17.7 ms, p = 0.034) and intraventricular septal-to-lateral delay (decrease of 0.9 ± 48.1 ms vs. increase of 15.9 ± 15.7 ms, p = 0.038), as assessed by tissue Doppler imaging. Accordingly, a reduction was observed in mitral regurgitation along with a trend towards reduced left ventricular volumes. CONCLUSIONS In this "real-world" setting systematic AVD optimization was associated with beneficial effects regarding biventricular pacing and left ventricular remodeling. These data show that AVD optimization may be advantageous in selected CRT patients.
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Affiliation(s)
- Raphael Korach
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland
| | - Peter C Kahr
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland
| | - Frank Ruschitzka
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland
| | - Jan Steffel
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland
| | - Andreas J Flammer
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland
| | - Stephan Winnik
- University Heart Center, Cardiology, University Hospital Zurich, Switzerland.
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Energy Dissipation in Resynchronization Therapy: Impact of Atrioventricular Delay. J Am Soc Echocardiogr 2019; 32:744-754.e1. [DOI: 10.1016/j.echo.2019.01.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Indexed: 11/20/2022]
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11
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Pujol-López M, San Antonio R, Mont L, Trucco E, Tolosana JM, Arbelo E, Guasch E, Heist EK, Singh JP. Electrocardiographic optimization techniques in resynchronization therapy. Europace 2019; 21:1286-1296. [DOI: 10.1093/europace/euz126] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 04/05/2019] [Indexed: 12/22/2022] Open
Abstract
Abstract
Cardiac resynchronization therapy (CRT) is a cornerstone of therapy for patients with heart failure, reduced left ventricular (LV) ejection fraction, and a wide QRS complex. However, not all patients respond to CRT: 30% of CRT implanted patients are currently considered clinical non-responders and up to 40% do not achieve LV reverse remodelling. In order to achieve the best CRT response, appropriate patient selection, device implantation, and programming are important factors. Optimization of CRT pacing intervals may improve results, increasing the number of responders, and the magnitude of the response. Echocardiography is considered the reference method for atrioventricular and interventricular (VV) intervals optimization but it is time-consuming, complex and it has a large interobserver and intraobserver variability. Previous studies have linked QRS shortening to clinical response, echocardiographic improvement and favourable prognosis. In this review, we describe the electrocardiographic optimization methods available: 12-lead electrocardiogram; fusion-optimized intervals (FOI); intracardiac electrogram-based algorithms; and electrocardiographic imaging. Fusion-optimized intervals is an electrocardiographic method of optimizing CRT based on QRS duration that combines fusion with intrinsic conduction. The FOI method is feasible and fast, further reduces QRS duration, can be performed during implant, improves acute haemodynamic response, and achieves greater LV remodelling compared with nominal programming of CRT.
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Affiliation(s)
- Margarida Pujol-López
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
| | - Rodolfo San Antonio
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Lluís Mont
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Emilce Trucco
- Department of Cardiology, Hospital Universitari Doctor Josep Trueta, Girona, Catalonia, Spain
| | - José María Tolosana
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Elena Arbelo
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Eduard Guasch
- Cardiology Department, Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Edwin Kevin Heist
- Cardiology Division, Cardiac Arrhythmia Service, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jagmeet P Singh
- Cardiology Division, Cardiac Arrhythmia Service, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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12
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Comparison of Echocardiographic and Electrocardiographic Mapping for Cardiac Resynchronisation Therapy Optimisation. Cardiol Res Pract 2019; 2019:4351693. [PMID: 30918721 PMCID: PMC6409049 DOI: 10.1155/2019/4351693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 11/06/2018] [Accepted: 11/14/2018] [Indexed: 11/17/2022] Open
Abstract
Study hypothesis We sought to investigate the association between echocardiographic optimisation and ventricular activation time in cardiac resynchronisation therapy (CRT) patients, obtained through the use of electrocardiographic mapping (ECM). We hypothesised that echocardiographic optimisation of the pacing delay between the atrial and ventricular leads-atrioventricular delay (AVD)-and the delay between ventricular leads-interventricular pacing interval (VVD)-would correlate with reductions in ventricular activation time. Background Optimisation of AVD and VVD may improve CRT patient outcome. Optimal delays are currently set based on echocardiographic indices; however, acute studies have found that reductions in bulk ventricular activation time correlate with improvements in acute haemodynamic performance. Materials and methods Twenty-one patients with established CRT criteria were recruited. After implantation, patients underwent echo-guided optimisation of the AVD and VVD. During this procedure, the participants also underwent noninvasive ECM. ECM maps were constructed for each AVD and VVD. ECM maps were analysed offline. Total ventricular activation time (TVaT) and a ventricular activation time index (VaT10-90) were calculated to identify the optimal AVD and VVD timings that gave the minimal TVaT and VaT10-90 values. We correlated cardiac output with these electrical timings. Results Echocardiographic programming optimisation was not associated with the greatest reductions in biventricular activation time (VaT10-90 and TVaT). Instead, bulk activation times were reduced by a further 20% when optimised with ECM. A significant inverse correlation was identified between reductions in bulk ventricular activation time and improvements in LVOT VTI (p < 0.001), suggesting that improved ventricular haemodynamics are a sequelae of more rapid ventricular activation. Conclusions EAM-guided programming optimisation may achieve superior fusion of activation wave fronts leading to improvements in CRT response.
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Vondrák J, Marek D, Večeřa J, Benešová K, Vojtíšek P. Cardiac resynchronization therapy - A comparison of VV delay optimization by 3D echocardiography using systolic dyssynchrony index and QRS width assessment at 6 months after CRT implantation. COR ET VASA 2018. [DOI: 10.1016/j.crvasa.2017.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Brugada J, Delnoy PP, Brachmann J, Reynolds D, Padeletti L, Noelker G, Kantipudi C, Rubin Lopez JM, Dichtl W, Borri-Brunetto A, Verhees L, Ritter P, Singh JP. Contractility sensor-guided optimization of cardiac resynchronization therapy: results from the RESPOND-CRT trial. Eur Heart J 2018; 38:730-738. [PMID: 27941020 PMCID: PMC5353752 DOI: 10.1093/eurheartj/ehw526] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 10/06/2016] [Indexed: 12/20/2022] Open
Abstract
Aims Although cardiac resynchronization therapy (CRT) is effective in patients with systolic heart failure (HF) and a wide QRS interval, a substantial proportion of patients remain non-responsive. The SonR contractility sensor embedded in the right atrial lead enables individualized automatic optimization of the atrioventricular (AV) and interventricular (VV) timings. The RESPOND-CRT study investigated the safety and efficacy of the contractility sensor system in HF patients undergoing CRT. Methods and results RESPOND-CRT was a prospective, randomized, double-blinded, multicentre, non-inferiority trial. Patients were randomized (2:1, respectively) to receive weekly, automatic CRT optimization with SonR vs. an Echo-guided optimization of AV and VV timings. The primary efficacy endpoint was the rate of clinical responders (patients alive, without adjudicated HF-related events, with improvement in New York Heart Association class or quality of life), at 12 months. The study randomized 998 patients. Responder rates were 75.0% in the SonR arm and 70.4% in the Echo arm (mean difference, 4.6%; 95% CI, −1.4% to 10.6%; P < 0.001 for non-inferiority margin −10.0%) (Table 2). At an overall mean follow-up of 548 ± 190 days SonR was associated with a 35% risk reduction in HF hospitalization (hazard ratio, 0.65; 95% CI, 0.46–0.92; log-rank P = 0.01). Conclusion Automatic AV and VV optimization using the contractility sensor was safe and as effective as Echo-guided AV and VV optimization in increasing response to CRT. ClinicalTrials.gov number NCT01534234
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Affiliation(s)
- Josep Brugada
- Cardiovascular Institute, Hospital Clinic, University of Barcelona, Barcelona, Spain
| | | | | | | | - Luigi Padeletti
- University of Florence, Italy and IRCCS Multimedica, Milan, Italy
| | | | | | | | - Wolfgang Dichtl
- Department of Internal Medicine III, Innsbruck Medical University, Innsbruck, Austria
| | | | | | | | - Jagmeet P Singh
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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15
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Socie P, Squara F, Semichon M, Thomas O, Khemache A, Riccini P, Squara P, Algalarrondo V, Moubarak G. Combination of the best pacing configuration and atrioventricular and interventricular delays optimization in cardiac resynchronization therapy. Pacing Clin Electrophysiol 2018; 41:362-367. [PMID: 29405324 DOI: 10.1111/pace.13294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 01/13/2018] [Accepted: 01/28/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Cardiac resynchronization therapy optimization can be pursued by left ventricular pacing vector selection and atrioventricular (AV) and interventricular (VV) delays optimization. The combination of these methods and its comparison with multipoint pacing (MPP) is scarcely studied. METHODS Using noninvasive cardiac output (CO) measurement, the best of five left ventricular pacing vectors was determined, then AV and VV delays optimization was applied on top of the best vector. Response to the optimization protocol was defined as a >5% CO increase compared to the standard biventricular configuration. RESULTS Twenty-two patients (18 men, age 71 ± 9 years) were included. Standard biventricular configuration increased CO compared to baseline (4.65 ± 1.55 L/min vs 4.27 ± 1.53 L/min, respectively, P = 0.02). The best quadripolar configuration increased CO to 4.85 ± 1.67 L/min (P = 0.03 compared to the standard biventricular configuration). AV then VV delay optimization both provided additional benefit (final CO 5.56 ± 2.03 L/min, P = 0.001 compared to the best quadripolar configuration). Fifteen (68%) patients responded to the optimization protocol. Anatomical MPP (based on maximal anatomical separation between electrodes) and electrical MPP (based on maximal electrical activation difference between electrodes) were evaluated in 16 patients and yielded a CO similar to that of the optimization procedure. CONCLUSIONS The combination of choosing the best quadripolar pacing configuration and optimizing atrioventricular and interventricular delays resulted in an improvement of cardiac output compared to standard biventricular stimulation in 68% of patients. The final cardiac output was comparable to multipoint pacing.
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Affiliation(s)
- Pierre Socie
- Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
| | - Fabien Squara
- Department of Cardiology, Pasteur University Hospital, Nice, France
| | - Marc Semichon
- Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
| | - Olivier Thomas
- Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
| | - Alain Khemache
- Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
| | - Philippe Riccini
- Department of Cardiology, Pasteur University Hospital, Nice, France
| | - Pierre Squara
- Intensive Care Unit, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
| | - Vincent Algalarrondo
- Department of Cardiology, Antoine Béclère Hospital, Université Paris-Sud, Clamart, France
| | - Ghassan Moubarak
- Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France
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16
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Zhao L, Zhao L, Pu L, Hua B, Wang Y, Li S, Li Q, Guo T. Left Univentricular Pacing by Rate-Adaptive Atrioventricular Delay in Treatment of Chronic Heart Failure. Med Sci Monit 2017; 23:3971-3980. [PMID: 28814710 PMCID: PMC5572785 DOI: 10.12659/msm.904348] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Cardiac resynchronization therapy (CRT) is efficacious in the treatment of chronic heart failure (CHF); however, because it is non-physiological, some patients are unresponsive. The present study used rate-adaptive atrioventricular delay (RAAVD) to track the physiological atrioventricular delay and investigated the effects of left univentricular pacing on CRT. Material/Methods Patients with CHF fulfilling the indication of CRT Class I were categorized into a left univentricular pacing by RAAVD group and a standard biventricular pacing group. Preoperative and postoperative electrocardiography QRS duration, echocardiographic indicators, quality of life, cardiac function, and annual treatment cost were estimated. The standard deviation (RS/R-SD5) of the S/R ratio in lead V1 at 5 heart rate segments in the left univentricular pacing by RAAVD was calculated, and the accuracy of RAAVD in tracking the physiological AV delay was evaluated. Results The comparison between the left univentricular pacing by RAAVD group and the standard biventricular pacing group after operation showed a significantly reduced QRS duration (137±11 vs. 144±11 ms, P<0.05), increased AVVTI (21.84±2.25 vs. 20.45±2.12 cm, P<0.05), reduced IVMD (64.27±12.29 vs. 71.39±13.64 ms, P<0.05), decreased MRA (3.09±1.12 vs. 3.73±1.19 cm2, P<0.05), and reduced average annual treatment cost (1.30±0.1 vs. 2.20±0.2 million Yuan, P<0.05). The RS/R-SD5 in the left univentricular pacing by RAAVD group was negatively correlated with improvements in cardiac function (r=−0.394, P=0.031). Conclusions Left univentricular pacing by RAAVD has treatment effects similar to those of standard biventricular pacing, and is an economically and physiologically effective method for biventricular systolic resynchronization in the treatment of CHF.
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Affiliation(s)
- Lulu Zhao
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Ling Zhao
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Lijin Pu
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Baotong Hua
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Yu Wang
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Shumin Li
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Qing Li
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
| | - Tao Guo
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China (mainland)
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Rodríguez Muñoz D, Moya Mur JL, Moreno J, Fernández-Golfín C, Franco E, Berlot B, Monteagudo JM, Matía Francés R, Hernández Madrid A, Zamorano JL. Mitral-Aortic Flow Reversal in Cardiac Resynchronization Therapy. Circ Arrhythm Electrophysiol 2017; 10:e004927. [DOI: 10.1161/circep.116.004927] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 04/13/2017] [Indexed: 11/16/2022]
Abstract
Background—
Flow entering the left ventricle is reversed toward the outflow tract through rotating reversal flow around the mitral valve. This was thought to facilitate early ejection, but had not been proved to date. We hypothesized that perfect coupling between reversal and ejection flow would occur at optimal atrioventricular delay (AVD), contributing to its hemodynamic superiority, and evaluated its applicability for AVD optimization.
Methods and Results—
Forty consecutive patients with cardiac resynchronization therapy underwent intracardiac flow analysis and AVD optimization. Reversal and ejection flow curves were studied. The presence and duration of reversal-ejection discontinuity were assessed for all programmed AVD. Reproducibility of each optimization method was evaluated through interobserver variability. Discontinuity between reversal and ejection flow was observed in all patients with longer than optimal AVD, increasing linearly with excess duration in AVD (linear
R
2
=0.976,
P
<0.001). Longer discontinuities implied progressive decreases in pre-ejection flow velocity in the left ventricular outflow tract, with consequent loss of flow momentum. The equation optimal AVD=programmed AVD–[1.2(discontinuity duration)]+4 accurately predicted optimal AVD. Short AVD systematically compromised reversal flow because of premature ejection. Agreement over optimal AVD was superior when assessed by flow reversal method (intraclass correlation coefficient =0.931;
P
<0.001) over both iterative and aortic velocity–time integral methods.
Conclusions—
Perfect coupling between mitral-aortic flow reversal and ejection flow in the left ventricle occurs at optimal AVD. As a result, full blood momentum in the outflow tract is used to facilitate early ejection. This can be measured and provides a new method for AVD optimization.
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Affiliation(s)
- Daniel Rodríguez Muñoz
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - José Luis Moya Mur
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Javier Moreno
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Covadonga Fernández-Golfín
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Eduardo Franco
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Bostjan Berlot
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Juan Manuel Monteagudo
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Roberto Matía Francés
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - Antonio Hernández Madrid
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
| | - José Luis Zamorano
- From the Cardiology Department, University Hospital Ramón y Cajal, Madrid, Spain (D.R.-M., J.L.M.M., J.M., C.F.-G., E.F., B.B., J.M.M., R.M.F., A.H.M., J.L.Z.); and University of Alcalá, Madrid, Spain (A.H.M., J.L.Z.)
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18
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Sinner GJ, Gupta VA, Seratnahaei A, Charnigo RJ, Darrat YH, Elayi SC, Leung SW, Sorrell VL. Atrioventricular dyssynchrony from empiric device settings is common in cardiac resynchronization therapy and adversely impacts left ventricular morphology and function. Echocardiography 2017; 34:496-503. [DOI: 10.1111/echo.13486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Gregory J. Sinner
- Department of Internal Medicine; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | - Vedant A. Gupta
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | - Arash Seratnahaei
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | | | - Yousef H. Darrat
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | - Samy C. Elayi
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | - Steve W. Leung
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
| | - Vincent L. Sorrell
- Division of Cardiovascular Medicine; Gill Heart Institute; University of Kentucky Medical Center; University of Kentucky; Lexington KY USA
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Novičenko V, Ratas I. Optimal waveform for the entrainment of oscillators perturbed by an amplitude-modulated high-frequency force. Phys Rev E 2017; 94:062213. [PMID: 28085462 DOI: 10.1103/physreve.94.062213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Indexed: 11/07/2022]
Abstract
We analyze limit cycle oscillators under perturbation constructed as a product of two signals, namely, an envelope with a period close to natural period of an oscillator and a high-frequency carrier signal. A theory for obtaining an envelope waveform that achieves the maximal frequency interval of entrained oscillators is presented. The optimization problem for fixed power and maximal allowed amplitude is solved by employing the phase reduction method and the Pontryagin's maximum principle. We have shown that the optimal envelope waveform is a bang-bang-type solution. Also, we have found "inversion" symmetry that relates two signals with different powers but the same interval of entrained frequencies. The theoretical results are confirmed numerically on FitzHugh-Nagumo oscillators.
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Affiliation(s)
- Viktor Novičenko
- Institute of Theoretical Physics and Astronomy, Vilnius University, Saulėtekio Avenue 3, LT-10222 Vilnius, Lithuania
| | - Irmantas Ratas
- Center for Physical Sciences and Technology, Saulėtekio Avenue 3, LT-10222 Vilnius, Lithuania
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20
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Soto Iglesias D, Duchateau N, Kostantyn Butakov CB, Andreu D, Fernandez-Armenta J, Bijnens B, Berruezo A, Sitges M, Camara O. Quantitative Analysis of Electro-Anatomical Maps: Application to an Experimental Model of Left Bundle Branch Block/Cardiac Resynchronization Therapy. IEEE JOURNAL OF TRANSLATIONAL ENGINEERING IN HEALTH AND MEDICINE-JTEHM 2016; 5:1900215. [PMID: 29164019 PMCID: PMC5477765 DOI: 10.1109/jtehm.2016.2634006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/08/2016] [Accepted: 11/14/2016] [Indexed: 01/02/2023]
Abstract
Electro-anatomical maps (EAMs) are commonly acquired in clinical routine for guiding
ablation therapies. They provide voltage and activation time information on a 3-D
anatomical mesh representation, making them useful for analyzing the electrical
activation patterns in specific pathologies. However, the variability between the
different acquisitions and anatomies hampers the comparison between different maps.
This paper presents two contributions for the analysis of electrical patterns in EAM
data from biventricular surfaces of cardiac chambers. The first contribution is an
integrated automatic 2-D disk representation (2-D bull’s eye plot) of the left
ventricle (LV) and right ventricle (RV) obtained with a quasi-conformal mapping from
the 3-D EAM meshes, that allows an analysis of cardiac resynchronization therapy
(CRT) lead positioning, interpretation of global (total activation time), and local
indices (local activation time (LAT), surrogates of conduction velocity,
inter-ventricular, and transmural delays) that characterize changes in the electrical
activation pattern. The second contribution is a set of indices derived from the
electrical activation: speed maps, computed from LAT values, to study the electrical
wave propagation, and histograms of isochrones to analyze regional electrical
heterogeneities in the ventricles. We have applied the proposed methods to look for
the underlying physiological mechanisms of left bundle branch block (LBBB) and CRT,
with the goal of optimizing the therapy by improving CRT response. To better
illustrate the benefits of the proposed tools, we created a set of synthetically
generated and fully controlled activation patterns, where the proposed representation
and indices were validated. Then, the proposed analysis tools are used to analyze EAM
data from an experimental swine model of induced LBBB with an implanted CRT device.
We have analyzed and compared the electrical activation patterns at baseline, LBBB,
and CRT stages in four animals: two without any structural disease and two with an
induced infarction. By relating the CRT lead location with electrical dyssynchrony,
we evaluated current hypotheses about lead placement in CRT and showed that optimal
pacing sites should target the RV lead close to the apex and the LV one distant from
it.
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Affiliation(s)
- David Soto Iglesias
- PhySense, Information and Communication Technologies DepartmentUniversitat Pompeu Fabra.,Cardiology DepartmentThorax Institute, Hospital Clinic
| | | | | | - David Andreu
- Cardiology DepartmentThorax Institute, Hospital Clinic
| | | | - Bart Bijnens
- PhySense, Information and Communication Technologies DepartmentUniversitat Pompeu Fabra.,Catalan Institution for Research and Advanced Studies
| | | | - Marta Sitges
- Cardiology DepartmentThorax Institute, Hospital Clinic
| | - Oscar Camara
- PhySense, Information and Communication Technologies DepartmentUniversitat Pompeu Fabra
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21
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Volpicelli M, Covino G, Capogrosso P. The clinical benefit of cardiac resynchronization therapy optimization using a device-based hemodynamic sensor in a patient with dilated cardiomyopathy: a case report. J Med Case Rep 2015; 9:289. [PMID: 26683613 PMCID: PMC4684612 DOI: 10.1186/s13256-015-0761-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 11/06/2015] [Indexed: 11/13/2022] Open
Abstract
Introduction Results on the evolution of the clinical status of patients undergoing cardiac resynchronization therapy with a defibrillator after automatic optimization of their cardiac resynchronization therapy are scarce. We observed a rapid and important change in the clinical status of our non-responding patient following activation of a sensor capable of weekly atrioventricular and interventricular delays' optimization. Case presentation A 78-year-old Caucasian man presented with dilated cardiomyopathy, left bundle branch block, a left ventricular ejection fraction of 35 %, New York Heart Association class III/IV heart failure, and paroxysmal atrial fibrillation. Our patient was implanted with a cardiac resynchronization device with a defibrillator and the SonRtip atrial lead. Right ventricular and left ventricular leads were also implanted. Because of the recurrence of atrial fibrillation, the automatic optimization was set off at discharge. Consequently, the device did not optimize atrioventricular and interventricular delays (programming at discharge: 125 ms for the atrioventricular delay and 0 ms for the interventriculardelay). Our patient was treated with an anti-arrhythmic drug. Five months after implantation, his clinical status remained impaired (left ventricular ejection fraction = 30 %). The SonR signal amplitude had also decreased from 0.52 g to 0.29 g. Nevertheless, because our patient was no longer presenting with atrial fibrillation, the anti-arrhythmic treatment was stopped and the SonR optimization system was activated. After 2 months of automatic cardiac resynchronization therapy with defibrillator optimization, our patient’s clinical status had significantly improved (left ventricular ejection fraction = 60 %, New York Heart Association class II) and the SonR signal amplitude had doubled shortly after the first weekly automatic optimization. Conclusion In this non-responding patient, device-based automatic cardiac resynchronization therapy optimization was shown to significantly improve his clinical status.
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What does device-based hemodynamic optimization bring to clinical practice in cardiac resynchronization therapy? REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2015. [DOI: 10.1016/j.repce.2015.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Oliveira MM. What does device-based hemodynamic optimization bring to clinical practice in cardiac resynchronization therapy? Rev Port Cardiol 2015; 34:511-3. [DOI: 10.1016/j.repc.2015.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/11/2015] [Indexed: 10/23/2022] Open
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Sagara K. Ventriculoventricular delay optimization of a cardiac resynchronization device. J Arrhythm 2014. [DOI: 10.1016/j.joa.2014.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Brugada J, Brachmann J, Delnoy PP, Padeletti L, Reynolds D, Ritter P, Borri-Brunetto A, Singh JP. Automatic optimization of cardiac resynchronization therapy using SonR-rationale and design of the clinical trial of the SonRtip lead and automatic AV-VV optimization algorithm in the paradym RF SonR CRT-D (RESPOND CRT) trial. Am Heart J 2014; 167:429-36. [PMID: 24655689 DOI: 10.1016/j.ahj.2013.12.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 12/03/2013] [Indexed: 11/17/2022]
Abstract
Although cardiac resynchronization therapy (CRT) is effective in most patients with heart failure (HF) and ventricular dyssynchrony, a significant minority of patients (approximately 30%) are non-responders. Optimal atrioventricular and interventricular delays often change over time and reprogramming these intervals might increase CRT effectiveness. The SonR algorithm automatically optimizes atrioventricular and interventricular intervals each week using an accelerometer to measure change in the SonR signal, which was shown previously to correlate with hemodynamic improvement (left ventricular [LV] dP/dtmax). The RESPOND CRT trial will evaluate the effectiveness and safety of the SonR optimization system in patients with HF New York Heart Association class III or ambulatory IV eligible for a CRT-D device. Enrolled patients will be randomized in a 2:1 ratio to either SonR CRT optimization or to a control arm employing echocardiographic optimization. All patients will be followed for at least 24 months in a double-blinded fashion. The primary effectiveness end point will be evaluated for non-inferiority, with a nested test of superiority, based on the proportion of responders (defined as alive, free from HF-related events, with improvements in New York Heart Association class or improvement in Kansas City Cardiomyopathy Questionnaire quality of life score) at 12 months. The required sample size is 876 patients. The two primary safety end points are acute and chronic SonR lead-related complication rates, respectively. Secondary end points include proportion of patients free from death or HF hospitalization, proportion of patients worsened, and lead electrical performance, assessed at 12 months. The RESPOND CRT trial will also examine associated reverse remodeling at 1 year.
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Affiliation(s)
- Josep Brugada
- Hospital Clinic, University of Barcelona, Barcelona, Spain.
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Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor. Adv Med 2014; 2014:307168. [PMID: 26556408 PMCID: PMC4590946 DOI: 10.1155/2014/307168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 06/24/2014] [Indexed: 12/03/2022] Open
Abstract
The Transvalvular Impedance (TVI) is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage. A TVI signal suitable to this purpose was present in 85% of the tested patients. A total of 230 capture failures, induced in 115 patients in both supine and sitting upright positions, were all promptly recognized by real-time TVI analysis (100% sensitivity). The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety. The pulse energy was then set at 4 times the threshold to test the alarm specificity during daily activity (sitting, standing up, and walking). The median prevalence of false alarms was 0.336%. The study shows that TVI-based ejection assessment is a valuable approach to the verification of pacing reliability and the autoregulation of ventricular stimulation energy.
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Affiliation(s)
- Frits W. Prinzen
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
| | - Kevin Vernooy
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
| | - Angelo Auricchio
- From the Departments of Physiology (F.W.P.) and Cardiology (K.V.), Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands; and the Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland (A.A.)
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Sohaib SMA, Whinnett ZI, Ellenbogen KA, Stellbrink C, Quinn TA, Bogaard MD, Bordachar P, van Gelder BM, van Geldorp IE, Linde C, Meine M, Prinzen FW, Turcott RG, Spotnitz HM, Wichterle D, Francis DP. Cardiac resynchronisation therapy optimisation strategies: systematic classification, detailed analysis, minimum standards and a roadmap for development and testing. Int J Cardiol 2013; 170:118-31. [PMID: 24239155 DOI: 10.1016/j.ijcard.2013.10.069] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/19/2013] [Accepted: 10/19/2013] [Indexed: 01/23/2023]
Abstract
In this article an international group of CRT specialists presents a comprehensive classification system for present and future schemes for optimising CRT. This system is neutral to the measurement technology used, but focuses on little-discussed quantitative physiological requirements. We then present a rational roadmap for reliable cost-effective development and evaluation of schemes. A widely recommended approach for AV optimisation is to visually select the ideal pattern of transmitral Doppler flow. Alternatively, one could measure a variable (such as Doppler velocity time integral) and "pick the highest". More complex would be to make measurements across a range of settings and "fit a curve". In this report we provide clinicians with a critical approach to address any recommendations presented to them, as they may be many, indistinct and conflicting. We present a neutral scientific analysis of each scheme, and equip the reader with simple tools for critical evaluation. Optimisation protocols should deliver: (a) singularity, with only one region of optimality rather than several; (b) blinded test-retest reproducibility; (c) plausibility; (d) concordance between independent methods; and (e) transparency, with all steps open to scrutiny. This simple information is still not available for many optimisation schemes. Clinicians developing the habit of asking about each property in turn will find it easier to win now down the broad range of protocols currently promoted. Expectation of a sophisticated enquiry from the clinical community will encourage optimisation protocol-designers to focus on testing early (and cheaply) the basic properties that are vital for any chance of long term efficacy.
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Affiliation(s)
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- National Heart & Lung Institute, Imperial College London, UK.
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Tavakolian K, Portacio G, Tamddondoust NR, Jahns G, Ngai B, Dumont GA, Blaber AP. Myocardial contractility: a seismocardiography approach. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2012:3801-4. [PMID: 23366756 DOI: 10.1109/embc.2012.6346795] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Features are extracted from seismocardiogram data to correlate with two indexes of myocardial contractility: dP/dt(max) (maximum first derivative of left ventricular pressure) and stroke volume. In the first study on three pigs, it is shown that the time period between the R peak of the ECG and the first peak of the SCG (R-AO period or pre-ejection period, PEP) correlated (r= -0.86) with dP/dt(max). In the second study, stroke volume is gradually reduced in five human subjects using lower body negative pressure. The same feature as the pigs (R-AO) is correlated the most with stroke volume (r= -0.90).
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Affiliation(s)
- Kouhyar Tavakolian
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada.
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Abstract
This article contains a review of the current status of remote monitoring and follow-up involving cardiac pacing devices and of the latest developments in cardiac resynchronization therapy. In addition, the most important articles published in the last year are discussed.
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