LAUSR

BACKGROUND We aimed to investigate if history of vigorous exercise was associated with changes in left ventricular morphology, left ventricular function and ventricular arrhythmias (VAs) in hypertrophic cardiomyopathy genotype positive, phenotype negative (Genotype+ LVH-) and in phenotype positive (HCM LVH+). METHODS In this cross sectional study we included 187 subjects (age 49±16years, 89(48%) female, 121(65%) HCM LVH+ and 66 (35%) Genotype+ LVH-) who answered a questionnaire on physical activity history. Exercise ≥6 metabolic equivalents was defined as vigorous. Subjects with a history of vigorous exercise ≥4h/week during ≥6years were defined as athletes. All underwent echocardiography and Holter monitoring. VAs were defined as aborted cardiac arrest, sustained or non-sustained ventricular tachycardia. RESULTS In both Genotype+ LVH- and HCM LVH+, lifetime vigorous exercise correlated with larger left ventricular end-diastolic volume (rho 0.44 and 0.38 respectively, both p<0.001). Lifetime vigorous exercise correlated with increased left ventricular mass in Genotype+ LVH- (rho 0.28, p=0.03), but not in HCM LVH+ (p=0.53). Left ventricular systolic function was similar between athletes and non-athletes in Genotype+ LVH- and HCM LVH+. HCM LVH+ athletes had lower E/e' (p=0.03) and higher e' (p=0.02) compared to non-athletes, while this difference was not observed in Genotype+ LVH-. Lifetime vigorous exercise was similar among HCM LVH+ with and without VAs (p=0.89). CONCLUSIONS Increased lifetime vigorous exercise was associated with larger left ventricular volumes in hypertrophic cardiomyopathy, but correlated to left ventricular mass only in Genotype+ LVH-. Vigorous exercise was associated with favorable diastolic function in HCM LVH+, and was not associated with VAs.