Clinical Studies
Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure: N Engl J Med 2015; 373:1095-1105September 17, 2015DOI: 10.1056/NEJMoa1506459
Background
Central sleep apnea is associated with poor prognosis and death in patients with heart failure. Adaptive servo-ventilation is a therapy that uses a noninvasive ventilator to treat central sleep apnea by delivering servo-controlled inspiratory pressure support on top of expiratory positive airway pressure. We investigated the effects of adaptive servo-ventilation in patients who had heart failure with reduced ejection fraction and predominantly central sleep apnea.
Methods
We randomly assigned 1325 patients with a left ventricular ejection fraction of 45% or less, an apnea–hypopnea index (AHI) of 15 or more events (occurrences of apnea or hypopnea) per hour, and a predominance of central events to receive guideline-based medical treatment with adaptive servo-ventilation or guideline-based medical treatment alone (control). The primary end point in the time-to-event analysis was the first event of death from any cause, lifesaving cardiovascular intervention (cardiac transplantation, implantation of a ventricular assist device, resuscitation after sudden cardiac arrest, or appropriate lifesaving shock), or unplanned hospitalization for worsening heart failure.
Results
In the adaptive servo-ventilation group, the mean AHI at 12 months was 6.6 events per hour. The incidence of the primary end point did not differ significantly between the adaptive servo-ventilation group and the control group (54.1% and 50.8%, respectively; hazard ratio, 1.13; 95% confidence interval [CI], 0.97 to 1.31; P=0.10). All-cause mortality and cardiovascular mortality were significantly higher in the adaptive servo-ventilation group than in the control group (hazard ratio for death from any cause, 1.28; 95% CI, 1.06 to 1.55; P=0.01; and hazard ratio for cardiovascular death, 1.34; 95% CI, 1.09 to 1.65; P=0.006).
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. (Funded by ResMed and others; SERVE-HF ClinicalTrials.gov number, NCT00733343.)
2004-Bon Jovi
it'll take more than a doctor to prescribe a remedy
Observations and recommendations communicated here are the perceptions of the writer and should not be misconstrued as medical advice.
RE: Clinical Studies
What I've recently read elsewhere (Medical College of WI researchers) is that in the case of centrals in a pt. with systolic heart failure, there seem to be no treatment alternatives other than permissive flow limitation (whatever that is), ASV and/or meds. So, guess I'm not too surprised to read that in such cases, ASV can't actually help much, and it can make things worse. I wonder if drugs are at all helpful in reducing centrals in a pt. with systolic heart failure?
David
RE: Clinical Studies
There have been a number of HF patients recently denied ASV therapy on the original study that identified a quantifiable 2.5% increased mortality risk for patients with HF and LVEF>40%. Considering HF is always fatal, it was a ridiculous position to just allow these people to suffocate.
If you've ever witnessed end-stage heart failure, you'd know.
RE: Clinical Studies
At the same time, systolic heart failure under its more common name is congestive heart failure, which, I've heard, has an average expected survival rate of something like five years. So, anything that could successfully treat it, I would call a medical miracle.
David
RE: Clinical Studies
A good point, Sleeprider. I believe you're referring to the palliative effects of ASV for these pts., even though this study concluded that ASV had "no significant effect on the primary end point." Quality of end of life is definitely important. And I have been close enough to end stage HF to have a good idea of what you speak.
David
RE: Clinical Studies
David thanks for your comments, and sorry you've had personal experience with this. My dad died of congestive heart failure, and without respiratory support, we just watched his intermittent breathing as he slept, and eventually didn't awaken. It took a lot away from the end of his life. I dearly wish I could have advocated more aggressively for some kind of respiratory support for his sleep. I just didn't understand.
RE: Clinical Studies
ya I asked my cardio Dr about this, left ventricular ejection fraction of 45%. all the patients in the study were actually below 30%, but because the study was structured for 45% that is what they had to publish.
Dr laughed and told me not to worry if my numbers were that low I would have to sit and rest after walking across the room.
I did look into it a little and IIRC with a full blown ventilator you have to be very careful with the settings because it can cause heart problems, something about getting the machine breathing sync'd with the patient breathing, you get it too far off and you have a problem
Since ASV is closer to a ventilator, if your heart is already compromised, it can cause a problem in those patients.