The following is a summary of “Randomized Controlled Trial of Moderate‐ and High‐Intensity Exercise Training in Patients With Hypertrophic Cardiomyopathy: Effects on Fitness and Cardiovascular Response to Exercise,” published in the October 2023 issue of Cardiology by Durstenfeld et al.
The study aimed to assess the comparative effectiveness of high-intensity training (HIT) versus moderate-intensity training (MIT) in patients diagnosed with hypertrophic cardiomyopathy. In this randomized trial, individuals were assigned to either 5 months of MIT or a regimen consisting of 1 month of MIT followed by 4 months of progressive HIT. Measurements of peak oxygen uptake (V˙O2), cardiac output, arteriovenous oxygen difference, left ventricular outflow gradient, and volumes were taken before and after the training period. Fifteen patients successfully completed the training (MIT, n=8, mean age 52±7 years; HIT, n=7, mean age 42±8 years). Both HIT and MIT showed a comparable improvement in peak V˙O2 by 1.3 mL/kg per min (P=0.009), with HIT demonstrating a slightly higher effect (+1.5 mL/kg per min) than MIT (+1.1 mL/kg per min) without statistical significance (group×exercise P=0.628).
Additionally, an increase in arteriovenous oxygen difference during exercise was observed (Δ1.6 mL/100 mL, P=0.005). HIT led to an elevation in left ventricular end‐diastolic volume (+17 mL, group×exercise P=0.015) compared to MIT. No serious arrhythmias or adverse cardiac events were reported throughout the study. While both HIT and MIT showcased improvements in fitness levels, this trial didn’t demonstrate clear superiority of either training modality. Despite being underpowered for safety outcomes, the study findings emphasize the positive peripheral and cardiac adaptations of exercise training in hypertrophic cardiomyopathy patients.