Effects of adaptive servo-ventilation on ventricular arrhythmias in patients with stable congestive heart failure and sleep-disordered breathing

Abstract

Congestive heart failure patients with reduced left ventricular ejection fraction (HFrEF) and sleep-disordered breathing (SDB) are at an increased risk of nocturnal cardiac arrhythmias. SDB can be effectively treated with adaptive servo-ventilation (ASV). Therefore, we tested the hypothesis that ASV therapy reduces nocturnal arrhythmias and heart rate in patients with HFrEF and SDB. In a non-prespecified subanalysis of a multicenter randomized controlled trial (ISRCTN04353156), 20 consecutive patients with stable HFrEF (age 67 ± 9 years; left ventricular ejection fraction, LVEF 32 ± 7 %) and SDB (apnea–hypopnea index, AHI 48 ± 20/h) were randomized to either an ASV therapy (n = 10) or an optimal medical treatment alone group (controls, n = 10). Polysomnography (PSG) with blinded centralized analysis and scoring was performed at baseline and at 12 weeks. The electrocardiograms (ECG) of the PSGs were analyzed with long-term (24-h) Holter ECG software (QRS-Card™ Cardiology Suite; Pulse Biomedical Inc., King of Prussia, PA, USA). There was a decrease in ventricular extrasystoles (VES) per hour of recording time in the ASV group compared to the control group (−8.1 ± 42.4 versus +9.8 ± 63.7/h, p = 0.356). ASV reduced the number of ventricular couplets and nonsustained ventricular tachycardias (nsVT) compared to the control group (−2.3 ± 6.9 versus +2.1 ± 12.7/h, p = 0.272 and −0.1 ± 0.5 versus +0.1 ± 1.1/h, p = 0.407, respectively). Mean nocturnal heart rate decreased in the ASV group compared to the controls (−2.0 ± 2.7 versus +3.9 ± 11.5/min, p = 0.169). The described changes were not significantly different between the groups. In HFrEF patients with SDB, ASV treatment may reduce nocturnal VES, couplets, nsVT, and mean nocturnal heart rate. The findings of the present pilot study underscore the need for further analyses in larger studies.