Long-Term Prognosis of Adaptive Servo Ventilation Therapy for Patients with Heart Failure -Consideration in Severity of Sleep- Disordered Breathing

Sleep-disordered breathing (SDB) has a close relation to heart failure (HF), the incidence of fatal cardiovascular events, and mortality.1 Adaptive servo-ventilation (ASV) therapy has been shown to be effective for central sleep apnea (CSA) and Cheyne–Stokes respiration (CSR).2,3 Recently, ASV therapy has also been used to treat patients with HF who also have CSA and CSR2,4,5 as well as patients with SDB, including those with obstructive sleep apnea.6,7 Cowie et al.8 reported that the ASV therapy for the patients with HF and reduced ejection fraction increased all-cause and cardiovascular mortality. However, previously, we reported that ASV therapy for patients with mild SDB resulted in almost equal improvements in brain natriuretic peptide (BNP) and left ventricular ejection fraction (LVEF) compared with patients with moderate and severe SDB, thus demonstrating that ASV therapy was effective for all patients with HF.9 Similarly, other reports suggested that the ASV therapy improved the LVEF, BNP, and the prognosis of patients with HF.6,10,11 However, previous reports have suggested that there is a negative relationship between the severity of SDB and prognosis.1,12 It remained unclear as to whether ASV could improve the long-term prognosis of patients with HF, regardless of the severity of SDB. We aimed to clarify whether ASV therapy improved the shortand longterm prognosis in patients with HF, regardless of the severity