- Known OSA being treated by CPAP, recommended coronary artery bypass surgery, concomitant moderate to severe structural valve disease, clinical instability (decompensated hypotension, heart failure, shock, refractory ventricular arrhythmias, acute conduction system disease, implanted defibrillator, or left ventricular ejection fraction ≤ 30%), limited life expectancy (< 1 year) due to a concomitant illness, prior or planned heart transplant or any other organ transplant, pregnancy or current nursing activity, or inability to give informed consent.