Obstructive sleep apnea is associated with nonsustained ventricular tachycardia in patients with hypertrophic obstructive cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is associated with arrhythmias and cardiovascular death. Obstructive sleep apnea (OSA) is highly prevalent and independently associated with atrial fibrillation in patients with HCM.

OBJECTIVE: The purpose of this study was to determine the relationship between nonsustained ventricular tachycardia (NSVT) and OSA in hypertrophic obstructive cardiomyopathy (HOCM).

METHODS: One hundred thirty consecutive patients with a confirmed diagnosis of HOCM in Fuwai Hospital between September 2017 and May 2018 were included. Polysomnography and Holter electrocardiography were performed in all patients.

RESULTS: Of 130 patients, 72 (55%) were diagnosed with OSA, including 38 with mild, 21 with moderate, and 13 with severe OSA, and 27 patients (21%) had NSVT. The prevalence of NSVT increased with the severity of OSA (none, mild, moderate, and severe: 12%, 16%, 33%, and 54%, respectively; P < .001 for trend). Compared to patients without NSVT, the apnea-hypopnea index was significantly higher in patients with NSVT among the different OSA groups (mild, moderate, and severe: 12 [11-13] vs 7 [6-8], P = .001; 24 [22-28] vs 19 [17-22], P = .01; and 54 [41-62] vs 34 [31-39], P = .008). In multivariate logistic regression analysis, family history of HCM or sudden cardiac death (odds ratio 6; 95% confidence interval 2-22; P = .005) and apnea-hypopnea index (odds ratio 1.07; 95% confidence interval 1.02-1.12; P = .001) were the only factors associated with NSVT after adjustment for age, sex, and body mass index.

CONCLUSION: The presence and severity of OSA in patients with HOCM is independently associated with NSVT, which is a risk factor for sudden cardiac death and cardiovascular death in this population.