Sleep-disordered breathing (SDB) with predominant obstructive or central sleep apnea (OSA/CSA) with CheyneStokes respiration (CSR) is a common, but underestimated and underappreciated, comorbidity in patients with heart failure (HF). Regardless of the type of HF (systolic or diastolic) or its etiology (ischemic, non-ischemic, valvular etc), the prevalence of SDB is remarkably high in this patient group, at 70-76%. Even more so in HF than in the general population, OSA and CSA in particular are independently associated with an impaired prognosis. This review details the pathophysiology of CSA-CSR in HF, highlights the challenges and tools available for diagnosis, explains the concept of adaptive servoventilation (ASV) therapy, and summarizes the existing literature on the use of ASV therapy in HF patients in general and HF with reduced ejection fraction in particular. (Circ J 2012; 76: 2305 -2317 Key Words: Adaptive servoventilation; Cheyne-Stokes respiration; Heart failure; Sleep-disordered breathing Figure 1. Scheme of the relative prevalence and importance of obstructive (OSA) and central sleep apnea (CSA) according to heart failure severity. With increasing impairment in cardiac function there is an increase in CSA prevalence. NYHA, New York Heart Association class.