Clinical outcomes in adult athletes with hypertrophic cardiomyopathy: a 7-year follow-up study

Objective Current guidelines recommend precautionary disqualification from competitive sports in patients with hypertrophic cardiomyopathy (HCM). We assessed the incidence of cardiovascular events in a cohort of patients with HCM engaged in long-term exercise programmes and competitive sport. Methods We reviewed data on 88 consecutive athletes diagnosed with HCM, from 1997 to 2017; 92% male, 98% Caucasian, median age 31 (IQR: 19–44) years. All participated in regular exercise programmes and competitive sport at study entry. We performed follow-up evaluation after 7±5 (1–21) years. 61 (69%) of the athletes had substantially reduced or stopped exercise and sport (ie, HCM-detrained), and 27 had continued with regular training and sport competitions (HCM-trained). At baseline evaluation, both groups were similar for age, gender balance, symptoms, ECG abnormalities, extent of left ventricular hypertrophy, arrhythmias and risk profile for sudden cardiac death/arrest. Results During the follow-up period, two participants suffered sudden cardiac arrest or death (0.3% per year) both outside of sport participation. In addition, 19 (22%) reported symptoms (syncope in 3, palpitations in 10, chest pain in 4 and dyspnoea in 2). The Kaplan-Meier analyses of freedom from combined sudden cardiac arrest/death and symptoms (log-rank test p=0.264) showed no differences between HCM-trained and detrained patients. Conclusion In this adult cohort of low-risk HCM athletes, voluntary decision to pursue in participation in competitive sport events was not associated with increased risk for major cardiac events or clinical worsening compared with decision to reduce or withdraw from exercise programmes and sport. Similar results may not be seen in younger or racially diverse athlete populations, or in patients with more severe HCM phenotypes.