[Sleep apnoea syndrome and cardiac failure].

Despite recent therapeutic advances, chronic cardiac failure is still associated with a significant morbidity and mortality. Sleep apnoea syndrome is common in this population, affecting almost half of these patients. However, it is rarely diagnosed and treated. There are two types of sleep apnoea syndrome, which can sometimes co-exist: the obstructive apnoea syndrome with collapse of the upper airways, and the central apnoea syndrome with cyclical Cheyne-Stokes respiration, linked with anomalies of central control. Apnoea leads to sympathetic stimulation and an increase in the left ventricular post-charge which can alter cardiac function and the prognosis. Diagnosis of sleep apnoea syndromes is now made with small ambulatory oxymeters which do not disturb sleep and which allow precise detection of episodes of desaturation. Treatment with positive pressure ventilation brings an improvement in daytime symptoms (fatigue, drowsiness) as well as an improvement in cardiac function. Screening for sleep apnoea is thus essential in patients with chronic heart failure, especially in those resistant to optimal drug treatment, in order to improve their management.