Comparative Influences Of Betablockers And Verapamil On Cardiac Outcomes In Hypertrophic Cardiomyopathy

Guidelines recommend betablockers as first line therapy in symptomatic patients with hypertrophic cardiomyopathy and non-dihydropyridine calcium channel blockers, particularly verapamil, as the second line therapy, despite absence of comparison trials between those two drugs. Since deleterious effects of verapamil have been reported in this setting, the present analysis aimed to evaluate the prognostic impact of betablockers and verapamil in a cohort of patients with hypertrophic cardiomyopathy. From a nation-wide cohort of 1434 patients with a diagnosis of hypertrophic cardiomyopathy included in the French prospective observational REgistry of hypertrophic cardioMYopathy (REMY), we retrospectively analysed individuals with sarcomeric hypertrophic cardiomyopathy included in the three largest centers and treated either with betablockers or verapamil. Patients with a cardiac defibrillator or a pacemaker or who underwent a procedure of atrial fibrillation or septal ablation were excluded. The primary endpoint was the composite of cardiovascular death, hospitalization for heart failure and hospitalization for atrial fibrillation. Out of 600 hypertrophic cardiomyopathy patients, 544 (91%) were treated with betablockers and 56 (9%) with verapamil. At inclusion, the two groups were comparable concerning presence/amplitude of obstruction and sudden cardiac death risk factors. At up to 8-year follow-up (median 3.9 years, IQR 2.1-5.8) no significant differences were observed in the primary endpoint (132 [24%] vs. 10 [18%] under betablockers or verapamil respectively, HR=1.84, 95% CI=0.94-3.63). In conclusion, in a real-world cohort of low risk patients with hypertrophic cardiomyopathy, verapamil therapy was not associated with a higher incidence of adverse events compared to betablocker therapy.