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Lima FVP, Andrade DDM, Filho JE, Souza PL, Azevedo LF, Coelho MM, de Lima JRP, Trevizan PF, Laterza MC, Martinez DG. Acute effect of ultramarathon on systolic and diastolic cardiac function: Systematic review and meta-analysis. Int J Cardiol 2024; 408:132106. [PMID: 38705202 DOI: 10.1016/j.ijcard.2024.132106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 04/09/2024] [Accepted: 04/26/2024] [Indexed: 05/07/2024]
Abstract
BACKGROUND Ultramarathon running poses physiological challenges, impacting cardiac function. This systematic review and meta-analysis explore the acute effects of single-stage ultramarathon running on cardiac function. METHODS Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations were followed. Searches covered Medline, Embase, CINAHL, SPORTDiscus, Web of Science, Central Cochrane, and Scopus. Random effects meta-analyses assessed left ventricular (LV) and right ventricular (RV) variables, expressed as mean differences (MD) with 95% confidence intervals (CI). RESULTS Among 6972 studies, 17 were included. Post-ultramarathon reductions were found in LV end-diastolic diameter (LVEDD) (-1.24; 95% CI = -1.77, -0.71 mm), LV end-diastolic volume (LVEDV) (-9.92; 95% CI = -15.25, -4.60 ml), LV stroke volume (LVSV) (-8.96 ml, 95% CI -13.20, -4.72 ml), LV ejection fraction (LVEF) (-3.71; 95% CI = -5.21, -2.22%), LV global longitudinal strain (LVGLS) (-1.48; 95% CI = -2.21, -0.76%), E/A (-0.30; 95% CI = -0.38, -0.22 cm/s), .E' (-1.35 cm/s, 95% CI -1.91, -0.79 cm/s), RV fractional area change (RVFAC) (-3.34, 95% CI = -5.84, -0.84%), tricuspid annular plane systolic excursion (TAPSE) (-0.12, 95% CI = -0.22, -0.02 cm), RV global longitudinal strain (RVGLS) (-1.73, 95% CI = -2.87, -0.59%), with increases in RV end-diastolic area (RVEDA) (1.89, 95% CI = 0.63, 3.14 cm2), RV Peak A' (1.32 cm/s, 95% CI 0.20, 2.44), and heart rate (18.24, 95% CI = 15.16, 21.32). No significant differences were observed in LV end-systolic diameter (LVESD), LV end-systolic volume (LVESV), RV end-diastolic diameter (RVEDD), RV Peak E', and RV Peak S'. CONCLUSIONS Evidence suggests immediate impairment of systolic and diastolic cardiac function post-ultramarathon running.
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Affiliation(s)
- Francisco Veríssimo Perrout Lima
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil.
| | - Diana de Medeiros Andrade
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - José Elias Filho
- Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - Pedro Lima Souza
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - Luciene Ferreira Azevedo
- Echocardiography Unit, University of São Paulo. Av. Dr. Enéas de Carvalho Aguiar, São Paulo, SP 44 - 05403-900, Brazil
| | - Marcelo Martins Coelho
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - Jorge Roberto Perrout de Lima
- Faculty of Physical Education and Sports, Federal University of Juiz de Fora. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - Patrícia Fernandes Trevizan
- Department of Physical Therapy, Federal University of Minas Gerais. Av. Presidente Carlos Luz, 6627 - Pampulha, Belo Horizonte, MG 31310-25, Brazil
| | - Mateus Camaroti Laterza
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
| | - Daniel Godoy Martinez
- Cardiovascular Research Unit and Exercise Physiology, Federal University of Juiz de Fora, Brazil. José Lourenço Kelmer, s/n, Martelos, Juiz de Fora 36036-900, Brazil
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2
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Soundappan D, Fung ASY, Loewenstein DE, Playford D, Strange G, Kozor R, Otton J, Ugander M. Decreased diastolic hydraulic forces incrementally associate with survival beyond conventional measures of diastolic dysfunction. Sci Rep 2023; 13:16396. [PMID: 37773251 PMCID: PMC10541860 DOI: 10.1038/s41598-023-41694-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 08/30/2023] [Indexed: 10/01/2023] Open
Abstract
Decreased hydraulic forces during diastole contribute to reduced left ventricular (LV) filling and heart failure with preserved ejection fraction. However, their association with diastolic function and patient outcomes are unknown. The aim of this retrospective, cross-sectional study was to determine the mechanistic association between diastolic hydraulic forces, estimated by echocardiography as the atrioventricular area difference (AVAD), and both diastolic function and survival. Patients (n = 5176, median [interquartile range] 5.5 [5.0-6.1] years follow-up, 1213 events) were selected from the National Echo Database Australia (NEDA) based on the presence of relevant transthoracic echocardiographic measures, LV ejection fraction (LVEF) ≥ 50%, heart rate 50-100 beats/minute, the absence of moderate or severe valvular disease, and no prior prosthetic valve surgery. NEDA contains echocardiographic and linked national death index mortality outcome data from 1985 to 2019. AVAD was calculated as the cross-sectional area difference between the LV and left atrium. LV diastolic dysfunction was graded according to 2016 guidelines. AVAD was weakly associated with E/e', left atrial volume index, and LVEF (multivariable global R2 = 0.15, p < 0.001), and not associated with e' and peak tricuspid regurgitation velocity. Decreased AVAD was independently associated with poorer survival, and demonstrated improved model discrimination after adjustment for diastolic function grading (C-statistic [95% confidence interval] 0.644 [0.629-0.660] vs 0.606 [0.592-0.621], p < 0.001) and E/e' (0.649 [0.635-0.664] vs 0.634 [0.618-0.649], p < 0.001), respectively. Therefore, decreased hydraulic forces, estimated by AVAD, are weakly associated with diastolic dysfunction and demonstrate an incremental prognostic association with survival beyond conventional measures used to grade diastolic dysfunction.
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Affiliation(s)
- Dhnanjay Soundappan
- Kolling Institute, Royal North Shore Hospital, and University of Sydney, Sydney, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, Australia
| | - Angus S Y Fung
- Kolling Institute, Royal North Shore Hospital, and University of Sydney, Sydney, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, Australia
| | - Daniel E Loewenstein
- Kolling Institute, Royal North Shore Hospital, and University of Sydney, Sydney, Australia
- Department of Clinical Physiology, Karolinska University Hospital, and Karolinska Institutet, Stockholm, Sweden
| | - David Playford
- School of Medicine, University of Notre Dame, Fremantle, Australia
| | - Geoffrey Strange
- School of Medicine, University of Notre Dame, Fremantle, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Rebecca Kozor
- Kolling Institute, Royal North Shore Hospital, and University of Sydney, Sydney, Australia
| | - James Otton
- Department of Cardiology, Liverpool Hospital, University of New South Wales, Liverpool, Australia
| | - Martin Ugander
- Kolling Institute, Royal North Shore Hospital, and University of Sydney, Sydney, Australia.
- St Vincent's Clinical School, University of New South Wales, Sydney, Australia.
- Department of Clinical Physiology, Karolinska University Hospital, and Karolinska Institutet, Stockholm, Sweden.
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3
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Systolic and diastolic function during cycling at the respiratory threshold between elderly and young healthy individuals. Sci Rep 2022; 12:3825. [PMID: 35264702 PMCID: PMC8907329 DOI: 10.1038/s41598-022-07933-7] [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: 01/15/2022] [Accepted: 02/28/2022] [Indexed: 11/20/2022] Open
Abstract
The hemodynamic consequences of aging have been extensively investigated during maximal incremental exercise. However, less is known about the effects of aging on hemodynamics during submaximal steady-state exercise. The aim of the present investigation was to compare the hemodynamics of healthy elderly and young subjects during an exercise bout conducted at the gas threshold (GET) intensity. Two groups of healthy, physically active subjects were studied: the elderly group—EG (n = 11; > 60 years old) and the young group—YG (n = 13; < 35 years old). Both groups performed a 5-min rectangular exercise test at the GET intensity. Hemodynamics were measured using echocardiography. The main finding was that stroke volume responses were higher in the YG than the EG (72.5 ± 16.7 vs. 52.4 ± 8.4 ml, respectively). The increased stroke volume capacity in the YG was the consequence of a greater capacity to increase cardiac preload and contractility and, to a lesser extent, to reduce systemic vascular resistance. Importantly, the atrial contribution to ventricular diastolic filling was substantially higher in the YG when compared to the EG.
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4
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Harbo MB, Stokke MK, Sjaastad I, Espe EKS. One step closer to myocardial physiology: From PV loop analysis to state-of-the-art myocardial imaging. Acta Physiol (Oxf) 2022; 234:e13759. [PMID: 34978759 DOI: 10.1111/apha.13759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/14/2021] [Accepted: 01/01/2022] [Indexed: 11/29/2022]
Abstract
Recent advances in cardiac imaging have revitalized the assessment of fundamental physiological concepts. In the field of cardiac physiology, invasive measurements with pressure-volume (PV) loops have served as the gold standard methodology for the characterization of left ventricular (LV) function. From PV loop data, fundamental aspects of LV chamber function are derived such as work, efficiency, stiffness and contractility. However, the parametrization of these aspects is limited because of the need for invasive procedures. Through the utilization of recent advances in echocardiography, magnetic resonance imaging and positron emission tomography, it has become increasingly feasible to quantify these fundamental aspects of LV function non-invasively. Importantly, state-of-the-art imaging technology enables direct assessment of myocardial performance, thereby extending functional assessment from the net function of the LV chamber, as is done with PV loops, to the myocardium itself. With a strong coupling to underlying myocardial physiology, imaging measurements of myocardial work, efficiency, stiffness and contractility could represent the next generation of functional parameters. The purpose of this review is to discuss how the new imaging parameters of myocardial work, efficiency, stiffness and contractility can bring cardiac physiologists, researchers and clinicians alike one step closer to underlying myocardial physiology.
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Affiliation(s)
- Markus Borge Harbo
- Institute for Experimental Medical Research Oslo University Hospital and University of Oslo Oslo Norway
- K.G. Jebsen Center for Cardiac Research University of Oslo Oslo Norway
| | - Mathis Korseberg Stokke
- Institute for Experimental Medical Research Oslo University Hospital and University of Oslo Oslo Norway
- K.G. Jebsen Center for Cardiac Research University of Oslo Oslo Norway
- Department of Cardiology Oslo University Hospital Rikshospitalet Oslo Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research Oslo University Hospital and University of Oslo Oslo Norway
- K.G. Jebsen Center for Cardiac Research University of Oslo Oslo Norway
| | - Emil Knut Stenersen Espe
- Institute for Experimental Medical Research Oslo University Hospital and University of Oslo Oslo Norway
- K.G. Jebsen Center for Cardiac Research University of Oslo Oslo Norway
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5
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Vallelonga F, Airale L, Tonti G, Argulian E, Milan A, Narula J, Pedrizzetti G. Introduction to Hemodynamic Forces Analysis: Moving Into the New Frontier of Cardiac Deformation Analysis. J Am Heart Assoc 2021; 10:e023417. [PMID: 34889114 PMCID: PMC9075239 DOI: 10.1161/jaha.121.023417] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The potential relevance of blood flow for describing cardiac function has been known for the past 2 decades, but the association of clinical parameters with the complexity of fluid motion is still not well understood. Hemodynamic force (HDF) analysis represents a promising approach for the study of blood flow within the ventricular chambers through the exploration of intraventricular pressure gradients. Previous experimental studies reported the significance of invasively measured cardiac pressure gradients in patients with heart failure. Subsequently, advances in cardiovascular imaging allowed noninvasive assessment of pressure gradients during progression and resolution of ventricular dysfunction and in the setting of resynchronization therapy. The HDF analysis can amplify mechanical abnormalities, detect them earlier compared with conventional ejection fraction and strain analysis, and possibly predict the development of cardiac remodeling. Alterations in HDFs provide the earliest signs of impaired cardiac physiology and can therefore transform the existing paradigm of cardiac function analysis once implemented in routine clinical care. Until recently, the HDF investigation was possible only with contrast‐enhanced echocardiography and magnetic resonance imaging, precluding its widespread clinical use. A mathematical model, based on the first principle of fluid dynamics and validated using 4‐dimensional‐flow‐magnetic resonance imaging, has allowed HDF analysis through routine transthoracic echocardiography, making it more readily accessible for routine clinical use. This article describes the concept of HDF analysis and reviews the existing evidence supporting its application in several clinical settings. Future studies should address the prognostic importance of HDF assessment in asymptomatic patients and its incorporation into clinical decision pathways.
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Affiliation(s)
- Fabrizio Vallelonga
- Division of Internal Medicine and Hypertension Department of Medical Sciences University of Torino Torino Italy
| | - Lorenzo Airale
- Division of Internal Medicine and Hypertension Department of Medical Sciences University of Torino Torino Italy
| | - Giovanni Tonti
- Institute of Cardiology and Centre of Excellence on Aging University of Chieti Chieti Italy
| | - Edgar Argulian
- Mount Sinai HeartIcahn School of Medicine at Mount Sinai New York NY
| | - Alberto Milan
- Division of Internal Medicine and Hypertension Department of Medical Sciences University of Torino Torino Italy
| | - Jagat Narula
- Mount Sinai HeartIcahn School of Medicine at Mount Sinai New York NY
| | - Gianni Pedrizzetti
- Department of Engineering and Architecture University of Trieste Trieste Italy
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6
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Commentary: Time to climb the ladder of causation. J Thorac Cardiovasc Surg 2021; 163:1209-1210. [PMID: 34419249 DOI: 10.1016/j.jtcvs.2021.07.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 07/28/2021] [Accepted: 07/28/2021] [Indexed: 11/19/2022]
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7
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Magnani S, Mulliri G, Roberto S, Sechi F, Ghiani G, Sainas G, Nughedu G, Vargiu R, Bassareo PP, Crisafulli A. Systolic and Diastolic Functions After a Brief Acute Bout of Mild Exercise in Normobaric Hypoxia. Front Physiol 2021; 12:650696. [PMID: 33967823 PMCID: PMC8103167 DOI: 10.3389/fphys.2021.650696] [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: 01/07/2021] [Accepted: 03/31/2021] [Indexed: 11/13/2022] Open
Abstract
Acute hypoxia (AH) is a challenge to the homeostasis of the cardiovascular system, especially during exercise. Research in this area is scarce. We aimed to ascertain whether echocardiographic, Doppler, and tissue Doppler measures were able to detect changes in systolic and diastolic functions during the recovery after mild exercise in AH. Twelve healthy males (age 33.5 ± 4.8 years) completed a cardiopulmonary test on an electromagnetically braked cycle-ergometer to determine their maximum workload (Wmax). On separate days, participants performed randomly assigned two exercise sessions consisting in 3 min pedalling at 30% of Wmax: (1) one test was conducted in normoxia (NORMO) and (2) one in normobaric hypoxia with FiO2 set to 13.5% (HYPO). Hemodynamics were assessed with an echocardiographic system. The main result was that the HYPO session increased parameters related to myocardial contractility such as pre-ejection period and systolic myocardial velocity with respect to the NORMO test. Moreover, the HYPO test enhanced early transmitral filling peak velocities. No effects were detected for left ventricular volumes, as end-diastolic, end-systolic, and stroke volume were similar between the NORMO and the HYPO test. Results of the present investigation support the hypothesis that a brief, mild exercise bout in acute normobaric hypoxia does not impair systolic or diastolic functions. Rather, it appears that stroke volume is well preserved and that systolic and early diastolic functions are enhanced by exercise in hypoxia.
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Affiliation(s)
- Sara Magnani
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy.,International PhD in Innovation Sciences and Technologies, University of Cagliari, Cagliari, Italy
| | - Gabriele Mulliri
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy.,International PhD in Innovation Sciences and Technologies, University of Cagliari, Cagliari, Italy
| | - Silvana Roberto
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Fabio Sechi
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Giovanna Ghiani
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Gianmarco Sainas
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Giorgio Nughedu
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Romina Vargiu
- Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Pier Paolo Bassareo
- University College of Dublin, Mater Misericordiae University Teaching Hospital, Dublin, Ireland
| | - Antonio Crisafulli
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy.,International PhD in Innovation Sciences and Technologies, University of Cagliari, Cagliari, Italy
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8
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Steding-Ehrenborg K, Hedström E, Carlsson M, Maksuti E, Broomé M, Ugander M, Magnusson M, Smith JG, Arheden H. Hydraulic force is a novel mechanism of diastolic function that may contribute to decreased diastolic filling in HFpEF and facilitate filling in HFrEF. J Appl Physiol (1985) 2021; 130:993-1000. [PMID: 33539261 DOI: 10.1152/japplphysiol.00890.2020] [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] [Indexed: 11/22/2022] Open
Abstract
A hydraulic force generated by blood moving the atrioventricular plane is a novel mechanism of diastolic function. The direction and magnitude of the force is dependent on the geometrical relationship between the left atrium and ventricle and is measured as the short-axis atrioventricular area difference (AVAD). In short, the net hydraulic force acts from a larger area toward a smaller one. It is currently unknown how cardiac remodeling affects this mechanism. The aim of the study was therefore to investigate this diastolic mechanism in patients with pathological or physiological remodeling. Seventy subjects [n = 11 heart failure with preserved ejection fraction (HFpEF), n = 10 heart failure with reduced ejection fraction (HFrEF), n = 7 signs of isolated diastolic dysfunction, n = 10 hypertrophic cardiomyopathy, n = 10 cardiac amyloidosis, n = 18 triathletes, and n = 14 controls] were included. Subjects underwent cardiac MR, and short-axis images of the left atrium and ventricle were delineated. AVAD was calculated as ventricular area minus atrial area and used as an indicator of net hydraulic force. At the onset of diastole, AVAD in HFpEF was -9.2 cm2 (median) versus -4.4 cm2 in controls, P = 0.02. The net hydraulic force was directed toward the ventricle for both but was larger in HFpEF. HFrEF was the only group with a positive median value (11.6 cm2), and net hydraulic force was throughout diastole directed toward the atrium. The net hydraulic force may impede cardiac filling throughout diastole in HFpEF, worsening diastolic dysfunction. In contrast, it may work favorably in patients with dilated ventricles and aid ventricular filling.NEW & NOTEWORTHY It is a previously unrecognized physiological mechanism of the heart that diastolic filling occurs with the help of hydraulics. In patients with heart failure with preserved ejection fraction, atrial dilatation may cause the net hydraulic force to work against cardiac filling, thus further augmenting diastolic dysfunction. In contrast, it may work favorably in patients with dilated ventricles, as in heart failure with reduced ejection fraction.
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Affiliation(s)
- Katarina Steding-Ehrenborg
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
| | - Erik Hedström
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden.,Department of Radiology, Skåne University Hospital, Lund, Sweden
| | - Marcus Carlsson
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
| | - Elira Maksuti
- Department of Physiology and Pharmacology, Anaesthesiology and Intensive Care, Karolinska Institute, Stockholm, Sweden
| | - Michael Broomé
- Department of Physiology and Pharmacology, Anaesthesiology and Intensive Care, Karolinska Institute, Stockholm, Sweden
| | - Martin Ugander
- Department of Clinical Physiology, Karolinska University Hospital, and Karolinska Institute, Stockholm, Sweden.,Kolling Institute, Royal North Shore Hospital, and Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Martin Magnusson
- Department of Clinical Sciences Malmö, Cardiology, Lund University, Lund, Sweden.,Department of Cardiology, Skåne University Hospital, Malmö, Sweden.,Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden
| | - J Gustav Smith
- Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.,Department of Clinical Sciences Lund, Cardiology, Lund University and Skåne University Hospital, Lund, Sweden.,Lund University Diabetes Center, Lund University, Lund, Sweden
| | - Håkan Arheden
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
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9
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Amrute JM, Zhang D, Padovano WM, Kovács SJ. E-wave asymmetry elucidates diastolic ventricular stiffness-relaxation coupling: model-based prediction with in vivo validation. Am J Physiol Heart Circ Physiol 2020; 320:H181-H189. [PMID: 33185111 DOI: 10.1152/ajpheart.00650.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Load, chamber stiffness, and relaxation are the three established determinants of global diastolic function (DF). Coupling of systolic stiffness and isovolumic relaxation has been hypothesized; however, diastolic stiffness-relaxation coupling (DSRC) remains unknown. The parametrized diastolic filling (PDF) formalism, a validated DF model incorporates DSRC. PDF model-predicted DSRC was validated by analysis of 159 Doppler E-waves from a published data set (22 healthy volunteers undergoing bicycle exercise). E-waves at varying (46-120 bpm) heart rates (HR) demonstrated variation in acceleration time (AT), deceleration time (DT), and E-wave peak velocity. AT, DT, and Epeak were converted into PDF parameters: stiffness ([Formula: see text]), relaxation ([Formula: see text]), and load (xo) using published numerical methods. Univariate linear regression showed that over a twofold increase in HR, AT, and DT decrease ([Formula: see text] = -0.44; P < 0.001 and r = -0.42; P < 0.001, respectively), while, DT/AT remains constant (r = -0.04; P = 0.67). Similarly, [Formula: see text] increases with HR (r = 0.55; P < 0.001), while [Formula: see text] has no significant correlation with HR (r = 0.08; P = 0.32). However, the dimensionless DSRC parameter ψ = c2/4k shows no significant correlation with HR (r = -0.03; P = 0.7). Furthermore, ψ is uniquely determined by DT/AT rather than AT or DT independently. Constancy of ψ in spite of a twofold increase in HR establishes that stiffness (k) and relaxation (c) are coupled and manifest via a HR-invariant parameter of E-wave asymmetry and should not be considered independent of each other. The manifestation of DSRC through E-wave asymmetry via ψ underscores the value of DT/AT as a physiological, mechanism-derived index of DF.NEW & NOTEWORTHY: Although diastolic stiffness and relaxation are considered independent chamber properties, the cardio-hemic inertial oscillation that generates E-waves obeys Newton's law. E-waves vary with heart rate requiring simultaneous change in stiffness and relaxation. By retrospective analysis of human heart-rate varying transmitral Doppler-data, we show that diastolic stiffness and relaxation are coupled and that the coupling manifests through E-wave asymmetry, quantified through a parametrized diastolic filling model-derived dimensionless parameter, which only depends on deceleration time and acceleration time, readily obtainable via standard echocardiography.
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Affiliation(s)
- Junedh M Amrute
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University in St. Louis, School of Medicine, St. Louis, Missouri.,Center for Cardiovascular Research, Cardiovascular Division, Department of Medicine, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - David Zhang
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - William M Padovano
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Sándor J Kovács
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University in St. Louis, School of Medicine, St. Louis, Missouri.,Center for Cardiovascular Research, Cardiovascular Division, Department of Medicine, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
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10
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Stanley A, Athanasuleas C, Buckberg G. How His bundle pacing prevents and reverses heart failure induced by right ventricular pacing. Heart Fail Rev 2020; 26:1311-1324. [PMID: 32318885 DOI: 10.1007/s10741-020-09962-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Ideal heart performance demands vigorous systolic contractions and rapid diastolic relaxation. These sequential events are precisely timed and interdependent and require the rapid synchronous electrical stimulation provided by the His-Purkinje system. Right ventricular (RV) pacing creates slow asynchronous electrical stimulation that disrupts the timing of the cardiac cycle and results in left ventricular (LV) mechanical asynchrony. Long-term mechanical asynchrony produces LV dysfunction, remodeling, and clinical heart failure. His bundle pacing preserves synchronous electrical and mechanical LV function, prevents or reverses RV pacemaker-induced remodeling, and reduces heart failure.
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Affiliation(s)
- Alfred Stanley
- Cardiovascular Associates of the Southeast, Birmingham, AL, USA
| | - Constantine Athanasuleas
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Gerald Buckberg
- Division of Cardiac Surgery, Department of Surgery, Cardiovascular Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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11
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Muir WW, Hamlin RL. Myocardial Contractility: Historical and Contemporary Considerations. Front Physiol 2020; 11:222. [PMID: 32296340 PMCID: PMC7137917 DOI: 10.3389/fphys.2020.00222] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/26/2020] [Indexed: 12/17/2022] Open
Abstract
The term myocardial contractility is thought to have originated more than 125 years ago and has remained and enigma ever since. Although the term is frequently used in textbooks, editorials and contemporary manuscripts its definition remains illusive often being conflated with cardiac performance or inotropy. The absence of a universally accepted definition has led to confusion, disagreement and misconceptions among physiologists, cardiologists and safety pharmacologists regarding its definition particularly in light of new discoveries regarding the load dependent kinetics of cardiac contraction and their translation to cardiac force-velocity and ventricular pressure-volume measurements. Importantly, the Starling interpretation of force development is length-dependent while contractility is length independent. Most historical definitions employ an operational approach and define cardiac contractility in terms of the hearts mechanical properties independent of loading conditions. Literally defined the term contract infers that something has become smaller, shrunk or shortened. The addition of the suffix “ility” implies the quality of this process. The discovery and clinical investigation of small molecules that bind to sarcomeric proteins independently altering force or velocity requires that a modern definition of the term myocardial contractility be developed if the term is to persist. This review reconsiders the historical and contemporary interpretations of the terms cardiac performance and inotropy and recommends a modern definition of myocardial contractility as the preload, afterload and length-independent intrinsic kinetically controlled, chemo-mechanical processes responsible for the development of force and velocity.
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Affiliation(s)
- William W Muir
- College of Veterinary Medicine, Lincoln Memorial University, Harrogate, TN, United States
| | - Robert L Hamlin
- College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
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12
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Bhagavan D, Padovano WM, Kovács SJ. Alternative diastolic function models of ventricular longitudinal filling velocity are mathematically identical. Am J Physiol Heart Circ Physiol 2020; 318:H1059-H1067. [PMID: 32142380 DOI: 10.1152/ajpheart.00681.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The spatiotemporal features of normal in vivo cardiac motion are well established. Longitudinal velocity has become a focus of diastolic function (DF) characterization, particularly the tissue Doppler e'-wave, manifesting in early diastole when the left ventricle (LV) is a mechanical suction pump (dP/dV < 0). To characterize DF and elucidate mechanistic features, several models have been proposed and have been previously compared algebraically, numerically, and in their ability to fit physiological velocity data. We analyze two previously noncompared models of early rapid-filling lengthening velocity (Doppler e'-wave): parametrized diastolic filling (PDF) and force balance model (FBM). Our initial numerical experiments sampled FBM-generated e'(t) contours as input to determine PDF model predicted fit. The resulting exact numerical agreement [standard error of regression (SER) = 9.06 × 10-16] was not anticipated. Therefore, we analyzed all published FBM-generated e'(t) contours and observed identical agreement. We re-expressed FBM's algebraic expressions for e'(t) and observed for the first time that model-based predictions for lengthening velocity by the FBM and the PDF model are mathematically identical: e'(t) = γe-αtsinh(βt), thereby providing exact algebraic relations between the three PDF parameters and the six FBM parameters. Previous pioneering experiments have independently established the unique determinants of e'(t) to be LV relaxation, restoring forces (stiffness), and load. In light of the exact intermodel agreement, we conclude that the three PDF parameters, relaxation, stiffness (restoring forces), and load, are unique determinants of DF and e'(t). Thus, we show that only the PDF formalism can compute the three unique, independent, physiological determinants of long-axis LV myocardial velocity from e'(t).NEW & NOTEWORTHY We show that two separate, independently derived physiological (kinematic) models predict mathematically identical expressions for LV-lengthening velocity (Doppler e'-wave), indicating that damped harmonic oscillatory motion is a physiologically accurate model of diastolic function. Although both models predict the same "overdamped" velocity contour, only one model solves the "inverse problem" and generates unique, lumped parameters of relaxation, stiffness (restoring force), and load from the e'-wave.
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Affiliation(s)
- Druv Bhagavan
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - William M Padovano
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Sándor J Kovács
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
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13
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How myofilament strain and strain rate lead the dance of the cardiac cycle. Arch Biochem Biophys 2019; 664:62-67. [PMID: 30710504 PMCID: PMC6589344 DOI: 10.1016/j.abb.2019.01.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 01/21/2019] [Accepted: 01/28/2019] [Indexed: 12/20/2022]
Abstract
Movement of the myocardium can modify organ-level cardiac function and its molecular (crossbridge) mechanisms. This motion, which is defined by myocardial strain and strain rate (muscle shortening, lengthening, and the speed of these movements), occurs throughout the cardiac cycle, including during isovolumic periods. This review highlights how the left ventricular myocardium moves throughout the cardiac cycle, how muscle mechanics experiments provide insight into the regulation of forces used to move blood in and out of the left ventricle, and its impact on (and regulation by) crossbridge and sarcomere kinetics. We specifically highlight how muscle mechanics experiments explain how myocardial relaxation is accelerated by lengthening (strain rate) during late systole and isovolumic relaxation, a lengthening which has been measured in human hearts. Advancing and refining both in vivo measurement and ex vivo protocols with physiologic strain and strain rates could reveal important insights into molecular (crossbridge) kinetics. These advances could provide an improvement in both diagnosis and precise treatment of cardiac dysfunction.
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14
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Sjöberg P, Töger J, Hedström E, Arvidsson P, Heiberg E, Arheden H, Gustafsson R, Nozohoor S, Carlsson M. Altered biventricular hemodynamic forces in patients with repaired tetralogy of Fallot and right ventricular volume overload because of pulmonary regurgitation. Am J Physiol Heart Circ Physiol 2018; 315:H1691-H1702. [PMID: 30265559 DOI: 10.1152/ajpheart.00330.2018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Intracardiac hemodynamic forces have been proposed to influence remodeling and be a marker of ventricular dysfunction. We aimed to quantify the hemodynamic forces in patients with repaired tetralogy of Fallot (rToF) to further understand the pathophysiological mechanisms as this could be a potential marker for pulmonary valve replacement (PVR) in these patients. Patients with rToF and pulmonary regurgitation (PR) > 20% ( n = 18) and healthy control subjects ( n = 15) underwent MRI, including four-dimensional flow. A subset of patients ( n = 8) underwent PVR and MRI after surgery. Time-resolved hemodynamic forces were quantified using 4D-flow data and indexed to ventricular volume. Patients had higher systolic and diastolic left ventricular (LV) hemodynamic forces compared with control subjects in the lateral-septal/LV outflow tract ( P = 0.011 and P = 0.0031) and inferior-anterior ( P < 0.0001 and P < 0.0001) directions, which are forces not aligned with blood flow. Forces did not change after PVR. Patients had higher RV diastolic forces compared with control subjects in the diaphragm-right ventricular (RV) outflow tract (RVOT; P < 0.001) and apical-basal ( P = 0.0017) directions. After PVR, RV systolic forces in the diaphragm-RVOT direction decreased ( P = 0.039) to lower levels than in control subjects ( P = 0.0064). RV diastolic forces decreased in all directions ( P = 0.0078, P = 0.0078, and P = 0.039) but were still higher than in control subjects in the diaphragm-RVOT direction ( P = 0.046). In conclusion, patients with rToF and PR had LV hemodynamic forces less aligned with intraventricular blood flow compared with control subjects and higher diastolic RV forces along the regurgitant flow direction in the RVOT and that of tricuspid inflow. Remaining force differences in the LV and RV after PVR suggest that biventricular pumping does not normalize after surgery. NEW & NOTEWORTHY Biventricular hemodynamic forces in patients with repaired tetralogy of Fallot and pulmonary regurgitation were quantified for the first time. Left ventricular hemodynamic forces were less aligned to the main blood flow direction in patients compared with control subjects. Higher right ventricular forces were seen along the pulmonary regurgitant and tricuspid inflow directions. Differences in forces versus control subjects remain after pulmonary valve replacement, suggesting that altered biventricular pumping does not normalize after surgery.
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Affiliation(s)
- Pia Sjöberg
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden
| | - Johannes Töger
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden.,Lund University, Department of Biomedical Engineering, Faculty of Engineering , Sweden
| | - Erik Hedström
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden.,Lund University, Department of Clinical Sciences, Lund, Diagnostic Radiology, Skåne University Hospital , Sweden
| | - Per Arvidsson
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden
| | - Einar Heiberg
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden.,Lund University, Department of Biomedical Engineering, Faculty of Engineering , Sweden
| | - Håkan Arheden
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden
| | - Ronny Gustafsson
- Lund University, Department of Clinical Sciences, Lund, Cardiothoracic Surgery, Skåne University Hospital , Sweden
| | - Shahab Nozohoor
- Lund University, Department of Clinical Sciences, Lund, Cardiothoracic Surgery, Skåne University Hospital , Sweden
| | - Marcus Carlsson
- Lund University, Department of Clinical Sciences, Lund, Clinical Physiology, Skåne University Hospital , Sweden
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15
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Hayabuchi Y, Ono A, Homma Y, Kagami S. Analysis of Right Ventricular Myocardial Stiffness and Relaxation Components in Children and Adolescents With Pulmonary Arterial Hypertension. J Am Heart Assoc 2018; 7:JAHA.118.008670. [PMID: 29674337 PMCID: PMC6015282 DOI: 10.1161/jaha.118.008670] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [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 The rate of left ventricular pressure decrease during isovolumic relaxation is traditionally assessed algebraically via 2 empirical indices: the monoexponential and logistic time constants (τE and τL). Since the pattern of right ventricular (RV) pressure decrease is quite different from that of the left ventricular, we hypothesized that novel kinematic model parameters are more appropriate and useful to evaluate RV diastolic dysfunction. Methods and Results Eight patients with pulmonary arterial hypertension (age 12.5±4.8 years) and 20 normal subjects (control group; age 12.3±4.4 years) were enrolled. The kinematic model was parametrized by stiffness/restoring Ek and damping/relaxation μ. The model predicts isovolumic relaxation pressure as a function of time as the solution of d2P/dt2+(1/μ)dP/dt+EkP=0, based on the theory that the pressure decay is determined by the interplay of inertial, stiffness/restoring, and damping/relaxation forces. In the assessment of RV diastolic function, τE and τL did not show significant differences between the pulmonary arterial hypertension and control groups (46.8±15.5 ms versus 32.5±14.6 ms, and 19.6±5.9 ms versus 14.5±7.2 ms, respectively). The pulmonary arterial hypertension group had a significantly higher Ek than the control group (915.9±84.2 s−2 versus 487.0±99.6 s−2, P<0.0001) and a significantly lower μ than the control group (16.5±4.3 ms versus 41.1±10.4 ms, P<0.0001). These results show that the RV has higher stiffness/elastic recoil and lower cross‐bridge relaxation in pulmonary arterial hypertension. Conclusions The present findings indicate the feasibility and utility of kinematic model parameters for assessing RV diastolic function.
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Affiliation(s)
| | - Akemi Ono
- Department of Pediatrics, Tokushima University, Tokushima, Japan
| | - Yukako Homma
- Department of Pediatrics, Tokushima University, Tokushima, Japan
| | - Shoji Kagami
- Department of Pediatrics, Tokushima University, Tokushima, Japan
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16
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Magnani S, Roberto S, Sainas G, Milia R, Palazzolo G, Cugusi L, Pinna V, Doneddu A, Kakhak SAH, Tocco F, Mercuro G, Crisafulli A. Metaboreflex-mediated hemodynamic abnormalities in individuals with coronary artery disease without overt signs or symptoms of heart failure. Am J Physiol Heart Circ Physiol 2017; 314:H452-H463. [PMID: 29127237 DOI: 10.1152/ajpheart.00436.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study was devised to investigate the effect of coronary artery disease (CAD) without overt signs of heart failure on the cardiovascular responses to muscle metaboreflex activation. We hypothesized that any CAD-induced preclinical systolic and/or diastolic dysfunction could impair hemodynamic response to the metaboreflex test. Twelve men diagnosed with CAD without any sign or symptoms of heart failure and 11 age-matched healthy control (CTL) subjects participated in the study. Subjects performed a postexercise muscle ischemia (PEMI) test to activate the metaboreflex. They also performed a control exercise recovery test to compare data from the PEMI test. The main results were that the CAD group reached a similar mean arterial blood pressure response as the CTL group during PEMI. However, the mechanism by which this response was achieved was different between groups. In particular, CAD achieved the target mean arterial blood pressure by increasing systemic vascular resistance (+383.8 ± 256.6 vs. +91.2 ± 293.5 dyn·s-1·cm-5 for the CAD and CTL groups, respectively), the CTL group by increasing cardiac preload (-0.92 ± 8.53 vs. 5.34 ± 4.29 ml in end-diastolic volume for the CAD and CTL groups, respectively), which led to an enhanced stroke volume and cardiac output. Furthermore, the ventricular filling rate response was higher in the CTL group than in the CAD group during PEMI ( P < 0.05 for all comparisons). This study confirms that diastolic function is pivotal for normal hemodynamics during the metaboreflex. Moreover, it provides evidence that early signs of diastolic impairment attributable to CAD can be detected by the metaboreflex test. NEW & NOTEWORTHY Individuals suffering from coronary artery disease without overt signs of heart failure may show early signs of diastolic dysfunction, which can be detected by the metaboreflex test. During the metaboreflex, these subjects show impaired preload and stroke volume responses and exaggerated vasoconstriction compared with controls.
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Affiliation(s)
- Sara Magnani
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Silvana Roberto
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Gianmarco Sainas
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Raffaele Milia
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Girolamo Palazzolo
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Lucia Cugusi
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Virginia Pinna
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Azzurra Doneddu
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | | | - Filippo Tocco
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Giuseppe Mercuro
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
| | - Antonio Crisafulli
- Department of Medical Sciences and Public Health, University of Cagliari , Cagliari , Italy
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17
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Lalande S, Mueller PJ, Chung CS. The link between exercise and titin passive stiffness. Exp Physiol 2017; 102:1055-1066. [PMID: 28762234 DOI: 10.1113/ep086275] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 07/11/2017] [Indexed: 12/27/2022]
Abstract
NEW FINDINGS What is the topic of this review? This review focuses on how in vivo and molecular measurements of cardiac passive stiffness can predict exercise tolerance and how exercise training can reduce cardiac passive stiffness. What advances does it highlight? This review highlights advances in understanding the relationship between molecular (titin-based) and in vivo (left ventricular) passive stiffness, how passive stiffness modifies exercise tolerance, and how exercise training may be therapeutic for cardiac diseases with increased passive stiffness. Exercise can help alleviate the negative effects of cardiovascular disease and cardiovascular co-morbidities associated with sedentary behaviour; this may be especially true in diseases that are associated with increased left ventricular passive stiffness. In this review, we discuss the inverse relationship between exercise tolerance and cardiac passive stiffness. Passive stiffness is the physical property of cardiac muscle to produce a resistive force when stretched, which, in vivo, is measured using the left ventricular end diastolic pressure-volume relationship or is estimated using echocardiography. The giant elastic protein titin is the major contributor to passive stiffness at physiological muscle (sarcomere) lengths. Passive stiffness can be modified by altering titin isoform size or by post-translational modifications. In both human and animal models, increased left ventricular passive stiffness is associated with reduced exercise tolerance due to impaired diastolic filling, suggesting that increased passive stiffness predicts reduced exercise tolerance. At the same time, exercise training itself may induce both short- and long-term changes in titin-based passive stiffness, suggesting that exercise may be a treatment for diseases associated with increased passive stiffness. Direct modification of passive stiffness to improve exercise tolerance is a potential therapeutic approach. Titin passive stiffness itself may be a treatment target based on the recent discovery of RNA binding motif 20, which modifies titin isoform size and passive stiffness. Translating these discoveries that link exercise and left ventricular passive stiffness may provide new methods to enhance exercise tolerance and treat patients with cardiovascular disease.
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Affiliation(s)
- Sophie Lalande
- Department of Kinesiology & Health Education, The University of Texas at Austin, Austin, TX, USA
| | | | - Charles S Chung
- Department of Physiology, Wayne State University, Detroit, MI, USA
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18
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Hayabuchi Y, Ono A, Homma Y, Kagami S. Assessment of pulmonary arterial compliance evaluated using harmonic oscillator kinematics. Pulm Circ 2017. [PMID: 28621582 PMCID: PMC5841894 DOI: 10.1177/2045893217714781] [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] [Indexed: 12/02/2022] Open
Abstract
We hypothesized that KPA, a harmonic oscillator kinematics-derived spring constant parameter of the pulmonary artery pressure (PAP) profile, reflects PA compliance in pediatric patients. In this prospective study of 33 children (age range = 0.5–20 years) with various cardiac diseases, we assessed the novel parameter designated as KPA calculated using the pressure phase plane and the equation KPA = (dP/dt_max)2/([Pmax – Pmin])/2)2, where dP/dt_max is the peak derivative of PAP, and Pmax – Pmin is the difference between the minimum and maximum PAP. PA compliance was also calculated using two conventional methods: systolic PA compliance (sPAC) was expressed as the stroke volume/Pmax – Pmin; and diastolic PA compliance (dPAC) was determined according to a two-element Windkessel model of PA diastolic pressure decay. In addition, data were recorded during abdominal compression to determine the influence of preload on KPA. A significant correlation was observed between KPA and sPAC (r = 0.52, P = 0.0018), but not dPAC. Significant correlations were also seen with the time constant (τ) of diastolic PAP (r = −0.51, P = 0.0026) and the pulmonary vascular resistance index (r = −0.39, P = 0.0242). No significant difference in KPA was seen between before and after abdominal compression. KPA had a higher intraclass correlation coefficient than other compliance and resistance parameters for both intra-observer and inter-observer variability (0.998 and 0.997, respectively). These results suggest that KPA can provide insight into the underlying mechanisms and facilitate the quantification of PA compliance.
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Affiliation(s)
| | - Akemi Ono
- Department of PediatricsTokushima UniversityTokushimaJapan
| | - Yukako Homma
- Department of PediatricsTokushima UniversityTokushimaJapan
| | - Shoji Kagami
- Department of PediatricsTokushima UniversityTokushimaJapan
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19
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Hydraulic forces contribute to left ventricular diastolic filling. Sci Rep 2017; 7:43505. [PMID: 28256604 PMCID: PMC5334655 DOI: 10.1038/srep43505] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 01/27/2017] [Indexed: 01/20/2023] Open
Abstract
Myocardial active relaxation and restoring forces are known determinants of left ventricular (LV) diastolic function. We hypothesize the existence of an additional mechanism involved in LV filling, namely, a hydraulic force contributing to the longitudinal motion of the atrioventricular (AV) plane. A prerequisite for the presence of a net hydraulic force during diastole is that the atrial short-axis area (ASA) is smaller than the ventricular short-axis area (VSA). We aimed (a) to illustrate this mechanism in an analogous physical model, (b) to measure the ASA and VSA throughout the cardiac cycle in healthy volunteers using cardiovascular magnetic resonance imaging, and (c) to calculate the magnitude of the hydraulic force. The physical model illustrated that the anatomical difference between ASA and VSA provides the basis for generating a hydraulic force during diastole. In volunteers, VSA was greater than ASA during 75-100% of diastole. The hydraulic force was estimated to be 10-60% of the peak driving force of LV filling (1-3 N vs 5-10 N). Hydraulic forces are a consequence of left heart anatomy and aid LV diastolic filling. These findings suggest that the relationship between ASA and VSA, and the associated hydraulic force, should be considered when characterizing diastolic function and dysfunction.
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20
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Omar AMS, Bansal M, Sengupta PP. Advances in Echocardiographic Imaging in Heart Failure With Reduced and Preserved Ejection Fraction. Circ Res 2016; 119:357-74. [DOI: 10.1161/circresaha.116.309128] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 06/10/2016] [Indexed: 12/20/2022]
Abstract
Echocardiography, given its safety, easy availability, and the ability to permit a comprehensive assessment of cardiac structure and function, is an indispensable tool in the evaluation and management of patients with heart failure (HF). From initial phenotyping and risk stratification to providing vital data for guiding therapeutic decision-making and monitoring, echocardiography plays a pivotal role in the care of HF patients. The recent advent of multiparametric approaches for myocardial deformation imaging has provided valuable insights in the pathogenesis of HF, elucidating distinct patterns of myocardial dysfunction and events that are associated with progression from subclinical stage to overt HF. At the same time, miniaturization of echocardiography has further expanded clinical application of echocardiography, with the use of pocket cardiac ultrasound as an adjunct to physical examination demonstrated to improve diagnostic accuracy and risk stratification. Furthermore, ongoing advances in the field of big data analytics promise to create an exciting opportunity to operationalize precision medicine as the new approach to healthcare delivery that aims to individualize patient care by integrating data extracted from clinical, laboratory, echocardiographic, and genetic assessments. The present review summarizes the recent advances in the field of echocardiography, with emphasis on their role in HF phenotyping, risk stratification, and optimizing clinical outcomes.
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Affiliation(s)
- Alaa Mabrouk Salem Omar
- From the Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, New York, New York (A.M.S.O., M.B., P.P.S.); and Department of Internal Medicine, Medical Division, National Research Centre, Dokki, Cairo, Egypt (A.M.S.O.)
| | - Manish Bansal
- From the Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, New York, New York (A.M.S.O., M.B., P.P.S.); and Department of Internal Medicine, Medical Division, National Research Centre, Dokki, Cairo, Egypt (A.M.S.O.)
| | - Partho P. Sengupta
- From the Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, New York, New York (A.M.S.O., M.B., P.P.S.); and Department of Internal Medicine, Medical Division, National Research Centre, Dokki, Cairo, Egypt (A.M.S.O.)
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