Prevalence and Impact of Central Sleep Apnea in Heart Failure
Section snippets
Pathophysiologic consequences of sleep apnea and hypopnea
There are a number of immediate and long-term pathophysiologic consequences of sleep apnea and hypopnea (Fig. 1). Immediate consequences of periodic breathing include hypoxemia and reoxygenation, hypercapnia and hypocapnia, and negative swings of intrathoracic pressure. These changes result in neurohormonal activation, release of inflammatory mediators, increases in transmural cardiac chambers, diminished oxygen delivery, and a host of other adverse effects reviewed elsewhere [35], [36], [37],
Impact of CSA on mortality
CSA may increase the risk of mortality in CHF [14], [15], [16], [17], [18]. Findley and colleagues [15] were the first to report that CSA was associated with increased mortality in patients with systolic heart failure. However, several recent studies have reported conflicting results. A major criticism in most studies is the small number of subjects, either in the CSA or in the control group. In addition, some of the studies combined cardiac transplantation with death as the primary endpoint.
Summary
Sleep apnea is commonly found in patients with systolic heart failure, and recent studies strongly suggest that the prevalence of central sleep apnea remains high, in spite of the use of contemporary treatment of heart failure including β-blockers. Furthermore, it has been shown that CSA may contribute to mortality of heart failure patients. However, the impact of therapy of sleep apnea on survival of heart failure patients needs to be further determined.
References (43)
- et al.
Prognostic value of plasma erythropoietin on mortality in patients with chronic heart failure
J Am Coll Cardiol
(2004) - et al.
Prevalence of sleep-disordered breathing in patients on a heart transplant waiting list
Chest
(1994) - et al.
Central sleep apnea, right ventricular dysfunction, and low diastolic blood pressure are predictors of mortality in systolic heart failure
J Am Coll Cardiol
(2007) - et al.
Cheyne-Stokes respiration and prognosis in congestive heart failure
Am J Cardiol
(1996) Sleep disorders in systolic heart failure: a prospective study of 100 male patients. The final report
Int J Cardiol
(2006)- et al.
Sleep-disordered breathing occurs frequently in stable outpatients with congestive heart failure
Chest
(2005) - et al.
Prevalence and clinical characteristics of sleep apnea in Chinese patients with heart failure
Int J Cardiol
(2007) - et al.
Cost effectiveness of cardiac resynchronization therapy in the comparison of medical therapy, pacing, and defibrillation in heart failure (COMPANION) trial
J Am Coll Cardiol
(2005) - et al.
Cardiac resynchronization therapy improves central sleep apnea and Cheyne-Stokes respiration in patients with chronic heart failure
J Am Coll Cardiol
(2004) - et al.
Cheyne-Stokes respiration with central sleep apnoea in chronic heart failure: proposals for a diagnostic and therapeutic strategy
Sleep Med Rev
(2006)