SERVE-HF was the first long-term randomised, controlled, international, multicentre study designed to assess the effects of adaptive servo-ventilation (ASV) on morbidity and mortality in patients with symptomatic chronic heart failure (HF) with reduced left ventricular ejection fraction ((LVEF ≤ 45%) and predominant central sleep apnoea-Cheyne-Stokes respiration (CSA-CSR).
• 1,325 patients enrolled
• 651 events collected
• 91 study centres
• 215 sites
• 24-month minimum follow-up period
• 312 patients enrolled in the main sub-study
Adjustment of ASV was performed in the hospital using polysomnographic or polygraphic monitoring. Default settings were used (expiratory positive airway pressure, 5 cm of water; minimum pressure support, 3 cm of water; and maximum pressure support, 10 cm of water). The expiratory positive airway pressure was increased manually to control obstructive sleep apnoea (OSA), and the maximum pressure support was increased to control CSA. A full face mask was recommended for the initiation of ASV. Patients were advised to use the ASV device for at least 5 hours per night, 7 days per week. Adherence to therapy was defined as ASV use for an average of at least 3 hours per night.
Clinic visits took place at study entry, after 2 weeks, at 3 and 12 months, and every 12 months thereafter until the end of the study. Patients in the ASV group also underwent polygraphy or polysomnography at each visit and ASV device data were downloaded.
312 of the patients involved in SERVE-HF were also enrolled in the major sub-study, that was aiming to assess changes in LVEF as measured by echocardiography from baseline to 12 months as its primary endpoint. It was also designed to examine changes in ventricular function and remodelling, biomarkers (such as brain natriuretic peptide), disease specific quality of life, cognitive function, anxiety and depression, and sleep and respiratory parameters.