Effect of vadaptive servo ventilation on mortality in patients with systolic heart failure and central sleep apnea

Background: In patients with heart failure and reduced ejection fraction (HFrEF), central sleep apnea (CSA) is associated with increased mortality. Adaptive servo ventilation (ASV) devices are most effective for alleviation of CSA. The safety of ASV has been questioned recently. We examined the association of ASV and mortality in our HFrEF-CSA patients. If ASV is associated with excess mortality, excess hourly use of ASV or pressure delivered should be associated with greater mortality. Methods: A prospective study of consecutive patients with HFrEF who were diagnosed with CSA and treated with ASV (n=77). Median follow up time was 64 months. Average nightly usage in all patients: 4.3 (0-10.2) hours; Average residual apnea hypopnea index ( AHI): 7.7 (0.1-37.6). There were 19 non-users. Multi variable model included age, sex, body mass index, AHI, LVEF, creatinine, atrial fibrillation, hypertension, coronary disease, implantable defibrillator and diabetes. Analysis using the exposure variable Hours-of-Use, showed that greater use decreased mortality, and proved close to statistical significance (p = 0.07), even with this limited sample size. An increase in use of one hour per night decreased the mortality rate by 18% (HR=0.82, 95% CI=0.66, 1.01). Patients who used ASV 3.6 hours (average for all patients) or more per night showed an 80% decrease in mortality compared to those who did not use their ASV (HR=0.48; 95% CI: 0.22, 1.05) (P Conclusion: In HFrEF patients with CSA, increased hours of use of the new generation ASV was associated with better survival.