CSB is characterized by cyclic crescendo-decrescendo respiratory effort and airflow during wakefulness or sleep, without upper airway obstruction. The decrescendo effort may be accompanied by cessation of respiration during sleep (central sleep apnea syndrome).

Patients who have heart failure and SDB can be asymptomatic or symptomatic. When OSAH is the predominant type of SDB, snoring and symptoms related to poor sleep quality (eg fatigue) are common. When CSB is the predominant type of SDB, symptoms due to CSB may be subtle or indistinguishable from those due to the underlying heart failure.

Night time angina and recurrent refractory arrhythmias (irregular heartbeats) may occur with either type of SDB. The evaluation of patients with heart failure should include questions about potential SDB symptoms.

Patients who report snoring, excessive daytime fatigue, or poor sleep quality may benefit from assessment via sleep lab. Sleep testing should also be considered in patients with heart failure who have night angina, recurrent arrhythmias, or refractory heart failure symptoms.

Patients who have heart failure and SDB likely have a poorer prognosis than patients who have heart failure without SDB. Optimization of the medical management of heart failure is the primary therapy for patients whose heart failure is complicated by SDB because it improves heart failure-related outcomes and may improve SDB. For patients who have heart failure complicated by SDB positive airway pressure with CPAP machine improve cardiac function, blood pressure, exercise capacity, and quality of life.