Tony Sampson, Mercer University College of Pharmacy
According the Chest journal, central sleep apnea is a result of an impaired signaling to the brain to control breathing during sleep. This condition is stated to occur frequently in patients with heart failure. 
Adaptive servo-ventilation is referred to as a form of mechanical ventilation that alleviates central sleep apnea by providing breath-by-breath adjustment of inspiratory pressure support to normalize breathing of the patient. 
|Title: Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure|
|Design||International, multicenter, randomized, parallel-group, event-driven study; N= 1325|
|Objective||To investigate the effects of adding adaptive servo-ventilation to guideline based medical treatment on survival and cardiovascular outcomes in patients who had heart failure with reduced ejection fraction and predominantly central sleep apnea|
|Study Groups||Control n= 659, adaptive servo-ventilation n= 666|
|Methods||Patients were randomly assigned to receive guideline-based medical treatment with adaptive servo-ventilation or guideline based medical treatment alone for their sleep apnea.|
|Primary Outcome Measure||The first event of death from any cause, lifesaving cardiovascular intervention, or unplanned hospitalization for worsening of heart failure|
|Baseline Characteristics||Characteristic||Control (n= 659)||Adaptive Servo-Ventilation (n= 666)|
|Age (yr) ± SD||69 ± 10.4||69.6 ± 9.5|
|Male sex – no. (%)||599 (90.9)||599 (89.9)|
|New York Heart Association (NYHA) class – no./total no. (%)|
|II||194/654 (29.7)||195/662 (29.5)|
|III||454/654 (69.4)||456/662 (68.9)|
|IIV||6/654 (0.9)||11/662 (1.7)|
|Results||Incidence of the primary endpoint for the adaptive servo-ventilation group and the control group was 54.1% and 50.8% respectively and hazard ratio was 1.13, with a 95% confidence interval of 0.97 to 1.31, (p= 0.10).|
|Adverse Events||Common Adverse Events: None reported|
|Serious Adverse Events: None reported|
|Percentage that Discontinued due to Adverse Events: None reported|
|Study Author Conclusions||Adaptive servo-ventilation had no significant effect on the primary end point in patients who had heart failure with reduced ejection fraction and predominantly central sleep apnea, but all-cause and cardiovascular mortality were both increased with this therapy.|
The results of this study demonstrated that servo-ventilation did not improve outcomes for patients who had heart failure with reduced ejection fraction and predominantly central sleep apnea. Some limitations of this study was that it was unblinded and the population was predominantly male. In conclusion, further follow-up from similar studies needs to be performed in order to determine if servo-ventilation can improve outcomes for patients with reduced ejection fraction heart failure along with central sleep apnea.
- Eckert DJ, Jordan AS, Merchia P, Malhotra A. Central sleep apnea: Pathophysiology and treatment. Chest. 2007;131(2):595-607.
- Aurora RN, Chowdhuri S, Ramar K, et al. The treatment of central sleep apnea syndromes in adults: practice parameters with an evidence-based literature review and meta-analyses. Sleep. 2012;35(1):17-40.
- Cowie MR, Woehrle H, Wegscheider K, et al. Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure. N Engl J Med. 2015;373(12):1095-105.