Exercise recommendations for patients with hypertrophic cardiomyopathy
Introduction
Hypertrophic cardiomyopathy (HCM) is a common inherited cardiovascular disease with a prevalence between 1:200–1:500.1 HCM presents with genotypic and phenotypic heterogeneity with the hallmark feature being left ventricular (LV) hypertrophy (LVH) in the absence of increased afterload states (e.g. hypertension). Mutations in genes encoding sarcomere proteins cause left ventricular wall thickening which may lead to increased LV outflow tract (LVOT) gradients as well as myocardial scarring and fibrosis. Due to these pathophysiological changes, a small number of patients with HCM will experience sudden cardiac arrest (SCA).2 Given initial pathological concerns that the underlying HCM substrate could be more arrhythmogenic in the setting of exercise with studies in athletes revealing HCM as a common etiology of sudden cardiac death (SCD),3 early guidelines recommended against sports participation and strenuous exercise in this patient population.4,5 However, there has been a paradigm shift with new studies supporting the safety and efficacy of moderate intensity exercise in patients with HCM due to the beneficial cardiorespiratory effects associated with exercise.6,7
Section snippets
Historical background for exercise restriction in HCM
Historically, HCM has been a leading cause of SCD in young athletes. A landmark paper published in 2003 identified HCM as the most common cause of death followed by commotio cordis and coronary-artery anomalies.8 Shortly thereafter, the 36th Bethesda Conference was held in New Orleans, Louisiana as a means to develop consensus recommendations for athletes with an identified cardiovascular abnormality.9 While this consensus document acknowledged the broad heterogeneity in genotypic and
Risk associated with inactivity and HCM
Exercise has become the standard of care for improving morbidity and mortality in patients with cardiovascular disease and in the general population. For every one metabolic equivalent of task (MET) improvement in CRF, there is a 10–20% reduction in mortality risk.20 And the benefits of exercise extend beyond CRF. Other known benefits of exercise include improved cognition and physical functioning, reduced anxiety and depression and lower risk of cancer (bladder, breast, colon, endometrium,
Evolution of data regarding exercise and HCM
Earlier consensus documents including the 36th Bethesda Conference proposed sports restriction were predominantly based on expert opinion. However, initial research on exercise and HCM from animal models with mutant myosin heavy chain have shown cardioprotective effects of early exercise when compared to exercise initiated later in life. These cardioprotective effects are likely related to increased vagal tone, reduced sympathetic tone, improved endothelial function, and improve diastolic
Exercise prescriptions for patients with HCM
As discussed earlier, the benefits of exercise may outweigh the risk of inactivity in patients with HCM. The 2020 AHA/ACC HCM guidelines advocate all patients with HCM who engage in regular exercise undergo a comprehensive evaluation including SDM regarding the risk and benefits of exercise and/or competitive sports participation.18 Before developing an exercise prescription, all patients with HCM should undergo a thorough initial evaluation including risk assessment for primary prevention ICD
Additional considerations to mitigate risk with exercise
Avoidance of dehydration and exposure to adverse environmental conditions (i.e. extremely hot/cold environments) is important in patients with obstructive HCM.4,18 Dehydration causes reduced preload which can lead to increased gradients and the potential to develop obstructive symptoms.28 Dehydration may also lead to electrolyte abnormalities and possible arrhythmia.4 HCM patients should be advised to practice adequate hydration before, during and after exercise. For patients living in hot
Special considerations for the elite athlete with HCM
Elite athletes wishing to participate in competitive sports should seek expert consultation with a provider familiar with HCM and ideally someone who understands the physical demands of the patient's sport.16 The foundation for developing an exercise prescription in this patient population includes a comprehensive evaluation and SDM regarding safety of sports participation and this evaluation should be repeated annually.18
EAPs should be discussed with coaches, families, fellow athletes and
Summary
HCM is a disease with a heterogeneous presentation. Early consensus documents recommended patients limit exercise to low-intensity sports due to concerns of disease progression and SCA. However, the morbidity and mortality associated with low levels of CRF have raised question regarding the safety of moderate- to high-intensity exercise in this patient population. Early data is favorable supporting moderate- and high-intensity exercise in this patient population and is ongoing. The cornerstone
Declaration of Competing Interest
Dr. Emery reports personal fees (Advisory Board, Speakers Bureau) from Bristol Meyers Squibb.
Dr. Martinez reports compensation for his role with Major League Soccer and from the Bristol Meyers Squibb advisory board.
Dr. Bryde has no conflicts to report.
References (54)
- et al.
Hypertrophic cardiomyopathy: clinical update
JACC: Heart Fail
(2018) - et al.
Eligibility and disqualification recommendations for competitive athletes with cardiovascular abnormalities: task force 3: hypertrophic cardiomyopathy, Arrhythmogenic right ventricular cardiomyopathy and other cardiomyopathies, and myocarditis: a scientific statement from the American Heart Association and American College of Cardiology
J Am Coll Cardiol
(2015) - et al.
Task force 4: HCM and other cardiomyopathies, mitral valve prolapse, myocarditis, and Marfan syndrome
J Am Coll Cardiol
(2005) Hypertrophic cardiomyopathy and other causes of sudden cardiac death in young competitive athletes, with considerations for preparticipation screening and criteria for disqualification
Cardiol Clin
(2007)- et al.
Demographics and epidemiology of sudden deaths in young competitive athletes: from the United States National Registry
Am J Med
(2016) Hypertrophic cardiomyopathy and exercise: mutually exclusive or beneficial?
Clin Sports Med
(2022)- et al.
2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: a report of the American College of Cardiology/American Heart Association joint committee on clinical practice guidelines
J Am Coll Cardiol
(2020) - et al.
A control theory-based pilot intervention ToIncrease physical activity in patients WithHypertrophic cardiomyopathy
Am J Cardiol
(2018) - et al.
Stages of psychological impact after diagnosis with serious or potentially lethal cardiac disease in young competitive athletes: a new model
J Electrocardiol
(2015) - et al.
Physical activity and other health behaviors in adults with hypertrophic cardiomyopathy
Am J Cardiol
(2013)