Prevalence and impact of atrial fibrillation in elderly patients with hypertrophic cardiomyopathy

Background: The study sought to identify the prevalence and the influence of atrial fibrillation (AF) on clinical course and outcomes in elderly patients with hypertrophic cardiomyopathy (HCM). Methods: From January 2014 to December 2017, 351 consecutive elderly patients diagnosed with HCM in our center were enrolled in this study. Clinical and echocardiographic variables were assessed in association with AF. The effect of AF on all-cause and cardiovascular mortality was evaluated with multivariate Cox proportional hazards models. Results: Of 351 patients (53% males, mean age 70.6 ± 5.2 years) with HCM, 122 (35%) had AF. AF was related to New York Heart Association (NYHA) class III/IV (OR=2.14, 95%CI: 1.27-3.63, P=0.005), history of stroke (OR=2.39, 95%CI: 1.16-4.91, P=0.018), left atrial dimension (OR=1.13, 95%CI: 1.08-1.19, P<0.001) and pulmonary hypertension (OR=2.91, 95%CI: 1.19-7.10, P=0.019). Over a median of follow-up period of 67 ± 22 months, 72 patients (21%) died. The five-year survival free from all-cause mortality was 83%, 70%, and 89% in the overall HCM population, AF, and non-AF groups, respectively. AF was a significantly independent predictor of all-cause mortality (HR=1.80, 95% CI: 1.02-3.86, P=0.042) and cardiovascular mortality (HR=1.89, 95% CI: 1.08-3.31, P=0.026). In addition, age and NYHA class III/IV were also independent predictors of all-cause and cardiovascular mortality. Conclusion: AF was common and related to a variety of clinical variables in elderly patients with HCM. As AF was independently associated with poor outcomes, comprehensive managements of AF were important for those elderly patients with HCM and AF.