Treating central sleep apnea in heart failure: outcomes revisited.

A recent enhanced appreciation of sleep–cardiovascular interactions, particularly in patients with congestive heart failure (CHF), has prompted careful consideration of the relevance of sleep-disordered breathing to CHF pathophysiology, progression, and treatment.1 Sleepdisordered breathing may be broadly classified as either obstructive sleep apnea (OSA) or central sleep apnea (CSA).1 The former is characterized by repetitive collapse of the upper airway, whereas in patients with CHF, the latter is most often due to periodic alternation of diminished ventilatory drive and compensatory hyperventilation typical of CheyneStokes respiration (Figure 1). CSA is likely a consequence rather than a cause of CHF. Although the mechanisms that underlie CSA/Cheyne-Stokes respiration in patients with CHF are not well understood, pulmonary congestion with increased lung J-receptor stimulation and greater chemosensitivity may play a role in the genesis of the periodic breathing that characterizes this disorder.1,2