Adaptive servo-ventilation may reduce atrial arrhythmia burden in patients with HF, sleep-disordered breathing

ORLANDO, Fla. — In a substudy of CAT-HF, patients with HF, sleep-disordered breathing and an implantable cardiac device assigned adaptive servo-ventilation plus optimal medical therapy had a reduction in atrial fibrillation/atrial tachycardia burden compared with those assigned optimal medical therapy alone.

The study, presented at the Heart Failure Society of America Scientific Assembly, also showed no benefit from minute-ventilation-targeted adaptive servo-ventilation (ASV; VPAP Adapt/Autoset CS, ResMed) in reducing ventricular arrhythmias in that population.

Sleep disorders and arrhythmias

“It is extremely well appreciated that sleep apnea increases the incidence of cardiac arrhythmias, including [atrial fibrillation], atrial ectopy, ventricular ectopies, ventricular arrhythmias of appropriate ICE shocks and sudden cardiac death,” Jonathan P. Piccini, MD, MHSc, associate professor of medicine and member of the Duke Clinical Research Institute, Duke University School of Medicine, said during a presentation.

Jonathan P. Piccini

Piccini and colleagues randomly assigned 215 patients with HF and apnea-hypopnea index 15 to optimal medical therapy alone or optimal medical therapy plus minute-ventilation-targeted ASV.

In the main results, presented at the European Society of Cardiology’s Annual Heart Failure Congress in May, there were no significant differences in the primary Global Rank Endpoint consisting of survival free from CV hospitalization and improvement in 6-minute walk distance between groups in the overall cohort (Wilcoxon P = .92; Cox P = .74) or in those with HF with reduced ejection fraction (HR = 1.18; 95% CI, 0.8-1.76; Wilcoxon P = .7; Cox P = .4), but the primary endpoint favored the ASV group in those with HF with preserved ejection fraction (HR = 0.36; 95% CI, 0.14-0.93; Wilcoxon P = .12; Cox P = .036), Piccini said.

Piccini presented results of a prespecified substudy evaluating whether ASV therapy would maintain sinus rhythm in patients from the cohort with an implanted cardiac device. Co-primary endpoints were change in AF burden at 6 months and ventricular tachycardia burden.

AF burden declined

There were 35 patients (19 assigned ASV; mean age, 60 years; 21% women; 16 controls; mean age, 69 years; 25% women) available for analysis of the AF endpoint, he said.

In the ASV cohort, AF burden reduced from 29.8% at baseline to 13.6% at 6 months, while in controls, AF burden increased from 5.6% at baseline to 8.4% at 6 months, according to the researchers. The difference from baseline in AF/atrial tachycardia burden was –20.5% in the ASV group and 30.7% in the control group (P = .002), Piccini said.

The difference was driven by those with central sleep apnea (P = .002) and those with nocturnal oxygen saturation < 90% (P = .003), but not in those with obstructive sleep apnea (P = 1), according to the researchers.

There were 46 patients available for analysis of the VT endpoint (28 in ASV group; mean age, 59 years; 21% women; 18 in control group; mean age, 62 years; 22% women).

In the ASV group, VT/ventricular fibrillation burden increased from 4.6% at baseline to 6.5% at 6 months, while in the control group, it decreased from 2.8% at baseline to 1.6% at 6 months, Piccini said, noting that there were no inappropriate shocks in either group, while 18% of the ASV group and 33% of the control group received appropriate shocks.

Limitations included that the study was stopped early, that the sample size was smaller than anticipated, that randomization in the main study was not stratified by device type, and that most of the cohort had HFrEF.

“Given the potential great importance of this finding, future studies should validate and quantify the efficacy of ASV for the reduction of AF in patients with and without HF,” Piccini said. – by Dave Quaile

Reference:

Piccini JP, et al. Late-Breaking Clinical Trial Update. Presented at: Heart Failure Society of America Scientific Assembly; Sept. 17-20, 2016; Orlando, Fla.

Disclosure : The CAT-HF study was funded by ResMed. Piccini reports receiving research grants from ARCA biopharma, Boston Scientific, Gilead, Johnson & Johnson, ResMed and St. Jude Medical; and consulting for Bayer Healthcare, Bristol-Myers Squibb/Pfizer, Janssen Pharmaceuticals and Medtronic.