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Mapelli M, Romani S, Magrì D, Merlo M, Cittar M, Masè M, Muratori M, Gallo G, Sclafani M, Carriere C, Zaffalon D, Salvioni E, Mattavelli I, Vignati C, De Martino F, Rovai S, Autore C, Sinagra G, Agostoni P. Exercise oxygen pulse kinetics in patients with hypertrophic cardiomyopathy. Heart 2022; 108:1629-1636. [PMID: 35273123 DOI: 10.1136/heartjnl-2021-320569] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 02/10/2022] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES Reduced cardiac output (CO) has been considered crucial in symptoms' genesis in hypertrophic cardiomyopathy (HCM). Absolute value and temporal behaviour of O2-pulse (oxygen uptake/heart rate (VO2/HR)), and the VO2/work relationship during exercise reflect closely stroke volume (SV) and CO changes, respectively. We hypothesise that adding O2-pulse absolute value and kinetics, and VO2/work relationship to standard cardiopulmonary exercise testing (CPET) could help identify more exercise-limited patients with HCM. METHODS CPETs were performed in 3 HCM dedicated clinical units. We retrospectively enrolled non-end-stage consecutive patients with HCM, grouped according to left ventricle outflow tract obstruction (LVOTO) at rest or during Valsalva manoeuvre (72% of patients with LVOTO <30; 10% between 30 and 49 and 18% ≥50 mm Hg). We evaluated the CPET response in HCM focusing on parameters strongly associated with SV and CO, such as O2-pulse and VO2, respectively, considering their absolute values and temporal behaviour during exercise. RESULTS We included 312 patients (70% males, age 49±18 years). Peak VO2 (percentage of predicted), O2-pulse and ventilation to carbon dioxide production (VE/VCO2) slope did not change across LVOTO groups. Ninety-six (31%) patients with HCM presented an abnormal O2-pulse temporal behaviour, irrespective of LVOTO values. These patients showed lower peak systolic pressure, workload (106±45 vs 130±49 W), VO2 (21.3±6.6 vs 24.1±7.7 mL/min/kg; 74%±17% vs 80%±20%) and O2-pulse (12 (9-14) vs 14 (11-17) mL/beat), with higher VE/VCO2 slope (28 (25-31) vs 27 (24-31)) (p<0.005 for all). Only 2 patients had an abnormal VO2/work slope. CONCLUSION None of the frequently used CPET parameters, either as absolute values or dynamic relationships, were associated with LVOTO. Differently, an abnormal temporal behaviour of O2-pulse during exercise, which is strongly related to inadequate SV increase, correlates with reduced functional capacity (peak and anaerobic threshold VO2 and workload) and increased VE/VCO2 slope, identifying more advanced disease irrespectively of LVOTO.
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Affiliation(s)
- Massimo Mapelli
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy.,Department of Clinical Sciences and Community Health, University of Milan, Milano, Italy
| | - Simona Romani
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Damiano Magrì
- Clinical and Molecular Medicine, University of Rome La Sapienza, Rome, Italy
| | - Marco Merlo
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Marco Cittar
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Marco Masè
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Manuela Muratori
- Cardiovascular Imaging, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Italy
| | - Giovanna Gallo
- Clinical and Molecular Medicine, University of Rome La Sapienza, Rome, Italy
| | - Matteo Sclafani
- Clinical and Molecular Medicine, University of Rome La Sapienza, Rome, Italy
| | - Cosimo Carriere
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Denise Zaffalon
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Elisabetta Salvioni
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Irene Mattavelli
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Carlo Vignati
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Fabiana De Martino
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Sara Rovai
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy
| | - Camillo Autore
- Clinical and Molecular Medicine, University of Rome La Sapienza, Rome, Italy
| | - Gianfranco Sinagra
- Cardiothoracovascular Department, Center for the Diagnosis and Treatment of Cardiomyopathies, Azienda Sanitaria Universitaria Giuliano Isontina [ASUGI] - University of Trieste, Trieste, Italy
| | - Piergiuseppe Agostoni
- Heart Failure Unit, Centro Cardiologico Monzino Istituto di Ricovero e Cura a Carattere Scientifico, Milano, Lombardia, Italy .,Department of Clinical Sciences and Community Health, University of Milan, Milano, Italy
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Schaff HV, Oberoi M, Dearani JA. How to build a successful hypertrophic cardiomyopathy team and ensure training the next generation of myectomy surgeons. Asian Cardiovasc Thorac Ann 2022; 30:19-27. [PMID: 35167375 DOI: 10.1177/02184923211053399] [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] [Indexed: 11/16/2022]
Abstract
Transaortic extended septal myectomy is the most reliable method for septal reduction for symptomatic patients with obstructive hypertrophic cardiomyopathy. In addition, surgical management of nonobstructive hypertrophic cardiomyopathy is possible for selected patients with diastolic heart failure and small left ventricular end-diastolic cavity dimensions. These procedures, however, are performed infrequently in many centers, and trainees may not be exposed to the preoperative evaluation and intraoperative management of patients with hypertrophic cardiomyopathy. In this paper, we review what we believe are the central features for creating a successful program for septal myectomy and detail our strategies to optimize instruction in these techniques for residents and fellows.
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Affiliation(s)
- Hartzell V Schaff
- Department of Cardiovascular Surgery, 4352Mayo Clinic, Rochester, MN, USA
| | - Meher Oberoi
- Department of Cardiovascular Surgery, 4352Mayo Clinic, Rochester, MN, USA
| | - Joseph A Dearani
- Department of Cardiovascular Surgery, 4352Mayo Clinic, Rochester, MN, USA
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Left ventricular ejection hemodynamics before and after relief of outflow tract obstruction in patients with hypertrophic obstructive cardiomyopathy and valvular aortic stenosis. J Thorac Cardiovasc Surg 2020; 159:844-852.e1. [DOI: 10.1016/j.jtcvs.2019.03.071] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/07/2019] [Accepted: 03/21/2019] [Indexed: 02/01/2023]
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Philipson DJ, DePasquale EC, Yang EH, Baas AS. Emerging pharmacologic and structural therapies for hypertrophic cardiomyopathy. Heart Fail Rev 2018; 22:879-888. [PMID: 28856513 DOI: 10.1007/s10741-017-9648-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Hypertrophic cardiomyopathy is the most common inherited heart disease. Although it was first described over 50 years ago, there has been little in the way of novel disease-specific therapeutic development for these patients. Current treatment practice largely aims at symptomatic control using old drugs made for other diseases and does little to modify the disease course. Septal reduction by surgical myectomy or percutaneous alcohol septal ablation are well-established treatments for pharmacologic-refractory left ventricular outflow tract obstruction in hypertrophic cardiomyopathy patients. In recent years, there has been a relative surge in the development of innovative therapeutics, which aim to target the complex molecular pathophysiology and resulting hemodynamics that underlie hypertrophic cardiomyopathy. Herein, we review the new and emerging therapeutics for hypertrophic cardiomyopathy, which include pharmacologic attenuation of sarcomeric calcium sensitivity, allosteric inhibition of cardiac myosin, myocardial metabolic modulation, and renin-angiotensin-aldosterone system inhibition, as well as structural intervention by percutaneous mitral valve plication and endocardial radiofrequency ablation of septal hypertrophy. In conclusion, while further development of these therapeutic strategies is ongoing, they each mark a significant and promising advancement in treatment for hypertrophic cardiomyopathy patients.
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Affiliation(s)
- Daniel J Philipson
- Department of Medicine, UCLA, 200 UCLA Medical Plaza Suite 420, Los Angeles, CA, 90095, USA.
| | - Eugene C DePasquale
- Ahmanson-UCLA Cardiomyopathy Center, Division of Cardiology, Department of Medicine, UCLA, Los Angeles, CA, USA
| | - Eric H Yang
- Division of Cardiology, Department of Medicine, UCLA, Los Angeles, CA, USA
| | - Arnold S Baas
- Ahmanson-UCLA Cardiomyopathy Center, Division of Cardiology, Department of Medicine, UCLA, Los Angeles, CA, USA
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Boudoulas KD, Boudoulas H. An Evolution of Management in Hypertrophic Cardiomyopathy: Myectomy, Alcohol Septal Ablation, Mitral Valve Replacement, MitraClip. Cardiology 2017; 137:54-57. [PMID: 28099954 DOI: 10.1159/000455068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 12/12/2016] [Indexed: 11/19/2022]
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Schaff HV. Transcatheter Mitral Valve Plication. J Am Coll Cardiol 2016; 67:2819-20. [DOI: 10.1016/j.jacc.2016.04.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 04/05/2016] [Indexed: 10/21/2022]
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Hypertrophic Cardiomyopathy in Childhood: Disease Natural History, Impact of Obstruction, and Its Influence on Survival. Ann Thorac Surg 2012; 93:840-8. [DOI: 10.1016/j.athoracsur.2011.10.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 09/10/2011] [Accepted: 10/11/2011] [Indexed: 11/22/2022]
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Gersh BJ, Maron BJ, Bonow RO, Dearani JA, Fifer MA, Link MS, Naidu SS, Nishimura RA, Ommen SR, Rakowski H, Seidman CE, Towbin JA, Udelson JE, Yancy CW. 2011 ACCF/AHA Guideline for the Diagnosis and Treatment of Hypertrophic Cardiomyopathy. Circulation 2011; 124:e783-831. [PMID: 22068434 DOI: 10.1161/cir.0b013e318223e2bd] [Citation(s) in RCA: 505] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Bernard J. Gersh
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see for detailed information
- ACCF/AHA Representative
| | - Barry J. Maron
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see for detailed information
- ACCF/AHA Representative
| | | | - Joseph A. Dearani
- Society of Thoracic Surgeons Representative
- American Association for Thoracic Surgery Representative
| | - Michael A. Fifer
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see for detailed information
- ACCF/AHA Representative
| | - Mark S. Link
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see for detailed information
- Heart Rhythm Society Representative
| | - Srihari S. Naidu
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see for detailed information
- Society for Cardiovascular Angiography and Interventions Representative
| | | | | | - Harry Rakowski
- ACCF/AHA Representative
- American Society of Echocardiography Representative
| | | | | | - James E. Udelson
- Heart Failure Society of America Representative
- American Society of Nuclear Cardiology Representative
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Gersh BJ, Maron BJ, Bonow RO, Dearani JA, Fifer MA, Link MS, Naidu SS, Nishimura RA, Ommen SR, Rakowski H, Seidman CE, Towbin JA, Udelson JE, Yancy CW, Jacobs AK, Smith SC, Anderson JL, Albert NM, Buller CE, Creager MA, Ettinger SM, Guyton RA, Halperin JL, Hochman JS, Krumholz HM, Kushner FG, Nishimura RA, Ohman EM, Page RL, Stevenson WG, Tarkington LG, Yancy CW. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy. J Thorac Cardiovasc Surg 2011; 142:e153-203. [DOI: 10.1016/j.jtcvs.2011.10.020] [Citation(s) in RCA: 223] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Gersh BJ, Maron BJ, Bonow RO, Dearani JA, Fifer MA, Link MS, Naidu SS, Nishimura RA, Ommen SR, Rakowski H, Seidman CE, Towbin JA, Udelson JE, Yancy CW, Jacobs AK, Smith SC, Anderson JL, Albert NM, Buller CE, Creager MA, Ettinger SM, Guyton RA, Halperin JL, Hochman JS, Krumholz HM, Kushner FG, Nishimura RA, Ohman EM, Page RL, Stevenson WG, Tarkington LG, Yancy CW. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: Executive summary. J Thorac Cardiovasc Surg 2011; 142:1303-38. [DOI: 10.1016/j.jtcvs.2011.10.019] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Gersh BJ, Maron BJ, Bonow RO, Dearani JA, Fifer MA, Link MS, Naidu SS, Nishimura RA, Ommen SR, Rakowski H, Seidman CE, Towbin JA, Udelson JE, Yancy CW. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation 2011; 124:2761-96. [PMID: 22068435 DOI: 10.1161/cir.0b013e318223e230] [Citation(s) in RCA: 594] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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12
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Gersh BJ, Maron BJ, Bonow RO, Dearani JA, Fifer MA, Link MS, Naidu SS, Nishimura RA, Ommen SR, Rakowski H, Seidman CE, Towbin JA, Udelson JE, Yancy CW. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2011; 58:2703-38. [PMID: 22075468 DOI: 10.1016/j.jacc.2011.10.825] [Citation(s) in RCA: 196] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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2011 ACCF/AHA Guideline for the Diagnosis and Treatment of Hypertrophic Cardiomyopathy: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Developed in collaboration with the American Association for Thoracic Surgery, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. J Am Coll Cardiol 2011; 58:e212-60. [PMID: 22075469 DOI: 10.1016/j.jacc.2011.06.011] [Citation(s) in RCA: 823] [Impact Index Per Article: 63.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Arshad W, Duncan AM, Francis DP, O'Sullivan CA, Gibson DG, Henein MY. Systole-diastole mismatch in hypertrophic cardiomyopathy is caused by stress induced left ventricular outflow tract obstruction. Am Heart J 2004; 148:903-9. [PMID: 15523325 DOI: 10.1016/j.ahj.2004.04.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Pharmacological stress is used to assess the degree of left ventricular (LV) subvalvular gradient in patients with hypertrophic cardiomyopathy (HCM), but there is little information about associated physiological changes. METHODS Echocardiography-Doppler ultrasound scanning measurements in 23 patients with HCM and 23 control subjects of similar age were studied at rest and at the end point of dobutamine stress. RESULTS In patients, the systolic time was normal at rest, but increased abnormally with stress. In patients, the total isovolumic contraction time failed to shorten, and the total ejection time increased abnormally. Changes in total ejection time correlated with an increase in peak subvalvular gradient in control subjects and patients (r = 0.52 and r = 0.66, respectively; P <.01 for both). In patients, the diastolic time was normal at rest, but shortened abnormally with stress. In patients, the isovolumic relaxation time fell abnormally, as did the filling time. Mitral E wave acceleration and left atrium size were unchanged with stress in control subjects, but consistently increased in patients with HCM, which indicates an increased early diastolic atrioventricular pressure gradient. CONCLUSION In HCM, systolic period increases abnormally with stress. This is not because of a loss of inotropy, but is directly related to the degree of LV outflow tract obstruction. As a result, the diastolic period fails to increase, reducing the time available for coronary flow, the LV filling pattern is modified, and the diastolic atrioventricular pressure gradient increases. These changes may contribute to symptom development and suggest why reducing LV outflow tract obstruction per se may be therapeutically useful in HCM.
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Affiliation(s)
- Waleed Arshad
- Department of Cardiology, Royal Brompton Hospital, London, United Kingdom.
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Sharma S, Elliott P, Whyte G, Jones S, Mahon N, Whipp B, McKenna WJ. Utility of cardiopulmonary exercise in the assessment of clinical determinants of functional capacity in hypertrophic cardiomyopathy. Am J Cardiol 2000; 86:162-8. [PMID: 10913477 DOI: 10.1016/s0002-9149(00)00854-7] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The utility of metabolic gas exchange measurements in evaluating the severity and determinants of exercise limitation was studied during upright symptom-limited cardiopulmonary exercise in 135 consecutive patients with hypertrophic cardiomyopathy (HC) and 50 healthy age- and gender-matched volunteers. Peak oxygen consumption (VO(2)) was less than predicted (age, gender, and size) in 99% patients. Peak VO(2) was significantly associated with New York Heart Association functional class; however, there was considerable overlap of peak VO(2) between classes I and III (70 +/- 15%, 56 +/- 15%, 35 +/- 11%, respectively). Patients with abnormal blood pressure responses and patients with chronotropic incompetence during exercise had lower percent-predicted peak VO(2) than patients with normal blood pressure and heart rate responses during exercise (p = 0.0001 and p <0.001, respectively). Percent-predicted peak VO(2) was similar in patients with and without resting left ventricular outflow obstruction. Of those patients with resting gradients, however, there was a strong inverse correlation between the magnitude of the gradient and peak VO(2) (r = 0.5; p <0.001). In conclusion, peak VO(2) is significantly related to New York Heart Association functional class in this group of patients with HC, but peak VO(2) is a superior measure of cardiovascular performance in individual patients. Our peak VO(2) data indicate that mechanical obstruction has an adverse pathophysiologic effect on functional capacity and provide the rationale to support treatments aimed at gradient reduction. Low peak VO(2) characteristics including those with normal or near-normal left ventricular wall thickness suggests that measurement of peak VO(2) may aid in the differential diagnosis between HC and athlete's heart.
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Affiliation(s)
- S Sharma
- Department of Cardiological Sciences, St. George's Hospital Medical School, London, United Kingdom
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Hay AS, Wilson DJ, Tyberg JV, Faulkner MG. Stroke normalized pressure: a useful parameter for the analysis of left ventricular outflow obstruction. Med Eng Phys 1996; 18:609-14. [PMID: 8953552 DOI: 10.1016/s1350-4533(96)00017-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A new method of presenting the in vivo left ventricular pressure-flow data is developed in the present study. This separates left ventricle ejection into unrestricted, progressively restricted and severely restricted cases. This method uses ejection volume and time to define a normalizing 'stroke' pressure, which is successful in collapsing the large variability of in vivo data to a few curves with characteristic shapes, depending on the degree of obstruction. Hypertrophic cardiomyopathy is shown to fall into both unrestricted and progressively restricted categories. Normal hearts form the unrestricted case, while a severe aortic valvular stenosis is characteristic of the severely restricted case.
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Affiliation(s)
- A S Hay
- Mechanical Engineering Department, University of Alberta, Edmonton, Canada
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Leachman RD. Ventricular dysfunction in hypertrophic obstructive cardiomyopathy. Tex Heart Inst J 1991; 18:165-9. [PMID: 15227475 PMCID: PMC324992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- R D Leachman
- Section of Adult Cardiology, Texas Heart Institute, St. Luke's Episcopal Hospital, Houston, Texas
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19
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Frandsen F, Mickley H. Regression of outflow tract obstruction subsequent to treatment with verapamil in hypertrophic obstructive cardiomyopathy. Int J Cardiol 1990; 28:375-6. [PMID: 2210905 DOI: 10.1016/0167-5273(90)90323-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A 29-year-old man suffering from hypertrophic obstructive cardiomyopathy was treated with verapamil 240 mg daily for 4.5 years. During this period the symptoms were reduced, and an intraventricular gradient diminished from 80 to 20 mm Hg, possibly due to a decrease in left ventricular ejection fraction combined with an improved diastolic filling.
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Affiliation(s)
- F Frandsen
- Department of Clinical Physiology, Odense University Hospital, Denmark
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