Sleep-disordered breathing and heart failure: an opportunity missed?

Sleep-disordered breathing (SDB) is common in patients with congestive heart failure (CHF). SDB appears to be associated with accelerated progression of heart failure. However, it is seldom recognised in cardiology clinics, especially as CHF patients with SDB rarely report symptoms specific to SDB, such as excessive day-time sleepiness. The term SDB incorporates both central sleep apnoea (CSA) and obstructive sleep apnoea (OSA). CSA is thought to be a consequence of heart failure, whereas OSA is thought to be associated with hypertension and excessive sympathetic nerve activation, which may exacerbate failure of the heart through haemodynamic and mechanical mechanisms. The treatment of SDB is likely to be an important complementary step in the management of heart failure, particularly OSA, where treatment with continuous positive airway pressure is well established and significant improvements in left ventricular ejection fraction plus quality of life have been reported. The treatment of CSA remains unclear and requires further research. This review will examine the prevalence, diagnosis, pathophysiology, clinical features and treatment of SDB in patients with CHF.