Performance of conventional and enhanced adaptive servoventilation (ASV) in heart failure patients with central sleep apnea who have adapted to conventional ASV.

PURPOSE: Adaptive servo-ventilation (ASV) is a positive pressure ventilator support system to normalize ventilation in patients with Cheyne-Stokes respiration (CSR). The latest generation enhanced ASV device (PaceWave; ResMed) has a new feature--auto-adjustment of EPAP. This study tested the hypothesis that enhanced ASV with auto-adjustment of EPAP (PaceWave) is non-inferior to conventional ASV (AutoSetCS). METHODS: This prospective, randomized, crossover, single-center study enrolled adult patients with stable heart failure (HF) and moderate-to-severe sleep-disordered breathing (SDB) who had been receiving conventional ASV therapy for at least 4 weeks. Patients received conventional ASV for one night and enhanced ASV on another night. Support settings for the two ASV devices were similar, with fixed expiratory positive airway pressure (EPAP) set to between 4 and 10 cm H2O and variable EPAP set to between 4 and 15 cm H2O. Full polysomnography was performed during ASV therapy on both nights. Endpoints were the number of nocturnal respiratory events and oxygen desaturations, and changes in blood pressure (BP). RESULTS: Levels of EPAP were comparable during the use of enhanced and conventional ASV, but minimum and maximum inspiratory pressure support values were significantly higher with the PaceWave device. All measures of apnea and hypopnea, and oxygen saturation, were significantly improved during ASV therapy with either device. There were no significant changes in BP or heart rate. CONCLUSIONS: Enhanced ASV is non-inferior to ASV with fixed EPAP in patients with chronic HF and CSR, with a trend towards better control of respiratory events.