Genotype Status and Arrhythmic Risk in Sport Participants with Hypertrophic Cardiomyopathy
Frédéric Myon, Mathilde Delatour, Nathalie Behar, François Carré, Erwan Donal, Frédéric SchnellAbstract
Aims
The impact of genotype on arrhythmic risk in sports-active hypertrophic cardiomyopathy (HCM) patients remains unclear. We compared outcomes between genotype-positive (G+) and genotype-negative (G-) athletes with HCM.
Methods
In this retrospective study, HCM patients actively engaged in sports underwent standardized baseline evaluation and follow-up. The primary endpoint included sudden cardiac death/arrest (SCD/SCA), appropriate implantable cardiovert-defibrillator (ICD) therapy, sustained/non-sustained ventricular tachycardia (SVT/NSVT). Secondary outcomes included a composite of ventricular arrhythmias, atrial fibrillation, ischemic stroke, and heart-failure hospitalization.
Results
Fifty-nine patients (age 40 years [23.2-50.0]) were followed for 6.3 years [3.0-12.6]. Twenty-nine participants (49.2%) carried a likely pathogenic or pathogenic variant, most commonly MYBPC3 (44.8%), MYH7 (24.1%) and TNNT2 (17.2%). At inclusion, median sport practice was 6.0 [3.0-10.0] hours-per-week, with 67.8% of competitors. At last follow-up, 88.1% remained active in sports. The ESC 5-years SCD risk score was slightly higher in G+ compared with G- patients (1.87% [1.47-3.67] vs 1.54% [1.24-2.20], p=0.048), but most of the participants were classified as low risk. Ventricular arrhythmias occurred in 20.7% of G+ and 23.3% of G- patients (p=0.807), with similar event–free survival (p=0.685). Most ventricular arrythmias were isolated NSVT (84.6%). Hard ventricular arrhythmic events were limited to two ICD-terminated ventricular fibrillations in G+ patients, one at rest and one during low-intensity exercise. The incidence of the composite secondary CV outcome was comparable between groups (31.0% vs. 33.3%, p=0.850).
Conclusions
In this exploratory cohort of sport active HCM patients, ventricular arrhythmic and cardiovascular event rates were similar between G+ and G- participants during follow-up.