FIG. 18:  One of these studies, reported by Cowie and colleagues,^[16] was the Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients with Heart Failure (SERVE-HF) trial. SERVE-HF compared ASV with optimal cardiac therapy in patients with symptomatic chronic systolic heart failure with a LVEF ≤45%.  The primary endpoint was a combined parameter of overall mortality, the number of hospitalizations, impairment of heart failure, heart transplantation, and sudden cardiac deaths, and the study ended when 651 cardiac events had been reached.

SERVE-HF did not show any significant difference in the primary outcome parameter between optimal cardiac therapy and treatment with the addition of ASV.  However, in a subgroup analysis looking at deaths from any cause and deaths from cardiovascular causes there was significantly higher mortality in patients treated with ASV compared with the control group.