Incidence of ischemic stroke and systemic embolism in patients with hypertrophic cardiomyopathy, nonvalvular atrial fibrillation, CHA₂DS₂-VASc score of ≤1 and without anticoagulant therapy

Data on the risk of ischemic stroke and systemic embolism (iSSE) events in patients with nonvalvular atrial fibrillation (NVAF), a CHA₂DS₂-VASc score of ≤1, hypertrophic cardiomyopathy (HCM), and without anticoagulant therapy are still lacking. The aim of this study was to investigate the incidence of iSSE events in these patients. We consecutively screened medical records of patients with HCM and NVAF referred to Fuwai Hospital between January 1994 and March 2014. The primary end point was iSSE events, defined as a composite of ischemic stroke and systemic embolism. Follow-up was carried out to ascertain end point status. Medical records of 522 patients with NVAF and HCM were screened. A total of 108 patients (20.7 %) with a CHA₂DS₂-VASc score of ≤1 and without anticoagulant therapy were enrolled and constituted our study population. After a median follow-up of 2.4 years (range 0.6–14.1 years; 376.2 patient-years), ischemic stroke occurred in 2 patients, resulting in death of 1 patient in the first year and paralysis of the other patient in the fourth year. No other iSSE events occurred. The incidence of iSSE was 0.9 % [95 % confidence interval (CI) 0.0–5.0 %] in the first year, and 0.5 % per 100 patient-years (95 % CI 0.1–1.9 %). The risk of iSSE events seems low in patients with NVAF, a CHA₂DS₂-VASc score of ≤1, HCM, and without anticoagulant therapy. Multicenter studies with sizeable study populations are needed to validate the risk of iSSE events in these patients.