[Sleep apnea and heart failure].

Sleep apnea can influence cardiac function, by which the development of heart failure is facilitated. Vice versa, chronic heart failure increases the risk for sleep apnea. Consequently, in patients with symptomatic chronic heart failure, sleep apnea is a frequent comorbidity occuring in up to 75% of cases. More than half of those suffer from central sleep apnea, whereas in the general population, obstructive sleep apnea is far more frequent. Both, the obstructive and the central sleep apnea lead to oxygen desaturations during the night which are followed by increases in serum catecholamines. Possibly, this is the main mechanism why the prognosis of patients with symptomatic heart failure and sleep apnea is much worse than that of patients without sleep apnea. Therefore, a screening of all heart failure patients for sleep apnea is mandatory. Currently, large studies are underway which investigate whether the treatment of sleep apnea, esp. central sleep apnea, will beneficially influence the clinical course of heart failure (SERVE-HF, ADVENT-HF). A new therapeutic approach for central sleep apnea is the phrenic nerve stimulation.