Adaptive servo-ventilation for central sleep apnea in systolic heart failure does not improve muscle sympathetic nerve activity: A SERVE-HF substudy

CSA is associated with poor prognosis in patients with chronic heart failure (CHF) with reduced Left Ventricular Ejection Fraction (LVEF). Adaptive servo-ventilation (ASV), is associated with an increase in all-cause and cardiovascular mortality. The underlying mechanisms are not yet elucidated. Because cardiovascular mortality in CHF is highly correlated to sympathetic activity (SA) and treating OSA has been shown to decrease SA, we hypothesized that ASV would reduce SA by normalizing breathing during sleep. Methods: In a substudy within the Serve-HF trial, we randomly assigned 40 patients with LVEF of 45% or less, an apnea–hypopnea index (AHI) of 15 or more events per hour, and u003e 50% of central events to receive guideline-based medical treatment without (control) or ASV. SA was measured using Muscle sympathetic nerve activity (MSNA). The primary outcome was change in MSNA after three months follow-up. Results: CHF patients (LVEF of 34.2±7.7 %, NYHA stage II and III 23(57.5%) and 17(42.5%) respectively), have a mean age of 71.3±11.7 and an AHI of 35.2±11 at baseline. MSNA did not differ among groups and follow-up, in burst/min from 47.97±8.25 to 44.28±11.01 vs 43.03±9.02 to 42.74±9.45 in the control and ASV groups respectively. Conclusions: Despite CSA treatment ASV had no beneficial effect on MSNA in CHF patients with reduced LVEF. This may partly explain why all-cause and cardiovascular mortality were both increased with this therapy. Further analyze should expand new hypothesize in order to understand pathways CSA and SA in CHF patients (Funded by ResMed, Resmed Foundation and Agir pour les maladies chroniques; NCT00733343.)