Whom are we treating with adaptive servo-ventilation? A clinical post hoc analysis

Background Recent evidence has shown that adaptive servo-ventilation (ASV) is contraindicated in patients with predominant central sleep apnea (CSA) and reduced left ventricular ejection fraction (LVEF <= 45%). The objective of this study was to assess the clinical usage of ASV in patients at the time-point of the release of a safety warning by type of SDB, breathing pattern and LVEF. Methods Patients of a cardiac and a respirology sleep center, both in Germany, who received ASV therapy were contacted between May and October 2015. Retrospective analyses included diagnostic polysomnography, polysomnography with continuous positive airway pressure prior to ASV initiation and echocardiography. Treatment emergent CSA was diagnosed after an appropriate treatment period on CPAP. Results 285 patients receiving ASV therapy (91 in the cardiac and 194 in the respirology setting) underwent diagnostic polysomnography. 233 (82%) patients had severe SDB, 94 (33%) predominant CSA, and 185 (65%) periodic breathing. 20% (n = 52) of patients had an LVEF of <= 45%. The most common indications for ASV were CSA in heart failure (41%) in the cardiac setting and treatment emergent CSA (80%) diagnosed after an appropriate period on CPAP in the respirology setting. The proportion of patients in whom ASV was contraindicated (CSA and LVEF <= 45%) was 16% in the cardiac setting and 9% in the respirology setting. Conclusion Clinical usage of ASV changed for a small subgroup of patients after release of the SERVE-HF results. Nevertheless, ASV treatment should be monitored and evaluated with diligence in the reminder indications.