Impact of adaptive servo‐ventilation on cardiovascular function and prognosis in heart failure patients with preserved left ventricular ejection fraction and sleep‐disordered breathing

Abstract

Effective pharmacotherapy for heart failure with preserved left ventricular ejection fraction (HFpEF) is still unclear. Sleep-disordered breathing (SDB) causes cardiovascular dysfunction, giving rise to factors involved in HFpEF. However, it remains unclear whether adaptive servo-ventilation (ASV) improves cardiovascular function and long-term prognosis of patients with HFpEF and SDB. Thirty-six patients with HFpEF (LVEF >50%) and moderate to severe SDB (apnoea-hypopnoea index >15/h) were enrolled. Study subjects (LVEF 56.0%, apnoea-hypopnoea index 36.5/h) were randomly assigned to two groups: 18 patients treated with medications and ASV (ASV group) and 18 patients not treated with ASV (non-ASV group). NYHA class, cardiac function including LVEF, left atrial volume index (LAVI), E/E', vascular function including flow-mediated dilatation (FMD) and cardio-ankle vascular index (CAVI), and levels of BNP and troponin T were determined at baseline and 6 months later. Patients were followed to register cardiac events after enrolment (follow-up 543 days). ASV therapy improved cardiac diastolic function and decreased CAVI and BNP (NYHA class, 2.3 to 1.5; LAVI, 48.6 to 42.6 mL/m(2); E/E', 12.8 to 7.1; CAVI, 9.0 to 7.7; BNP, 121.5 to 58.1 pg/mL, P < 0.0125, respectively). LVEF, FMD, and troponin T did not change significantly in either group. Importantly, the event-free rate was significantly higher in the ASV group than in the non-ASV group (94.4% vs. 61.1%, log-rank P < 0.05). ASV may improve the prognosis of HFpEF patients with SDB, with favourable effects such as improvement of symptoms, cardiac diastolic function, and arterial stiffness. ASV may be a useful therapeutic tool for HFpEF patients with SDB.