Central sleep-apnea (CSA) with associated Cheyne-Stokes breathing patterns effects up to 40% of patients with low ejection fraction heart failure.   Given that CSA is an independent marker for poor prognosis and mortality, treatment of CSA has been identified as a potential target to improve heart failure outcomes.  This study randomized 1325 patients with low ejection fraction heart failure (mean EF 32%) and a diagnosis of CSA to either overnight adaptive servo-ventilation or guideline directed medical therapy alone. Adaptive servo-ventilation (ASV) is a noninvasive therapy that provides inspiratory pressure support in addition to expiratory positive airway pressure.  Trial patients were followed for a mean of 31 months, with a primary composite end-point of all-cause mortality, hospitalization for heart failure or life-saving cardiac intervention.  Although ASV resulted in a significant decrease in the apnea-hypopnea index among patients in the intervention arm, suggesting the treatment was effective in alleviating CSA.  However, ASV treatment of CSA resulted in increased all-cause mortality (hazard ratio, 1.28; 95% CI, 1.06 to 1.55; P=0.01) and cardiovascular mortality (hazard ratio, 1.34; 95% CI, 1.09 to 1.65; P=0.006) in this population of patients with low ejection fraction.

Conclusions

Although central sleep apnea portends a poor prognosis in heart failure, treatment of central sleep apnea with adaptive servo-ventilation resulted in greater mortality in patients with reduced ejection fraction.

Summarized by Hussain Contractor and Steven M. Bradley

Cowie MR, Woehrle H, Wegscheider K, Angermann C, d’Ortho MP, Erdmann E, Levy P, Simonds AK, Somers VK, Zannad F, Teschler H.  Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure. N Engl J Med. 2015 Sep 17;373(12):1095-105.