[Effect of long-term oxygen therapy on sleep architecture in patients with severe dilated cardiomyopathy and Cheyne-Stokes respiration].

Patients suffering from severe heart failure may develop breathing disorders during sleep. Results may be heavy disturbances in sleep architecture, worsening of haemodynamics and of the prognosis of these patients. Causes of breathing disorders are probably instability of breathing regulation caused by hypoxaemia, hypocapnia, and prolonged blood circulation time. This study examined the influence exercised by different concentrations of continuously applied oxygen during night time on breathing disorders, oxygen saturation and sleep architecture in patients with severe heart failure (NYHA III-IV). All patients showed an improvement in sleep architecture. Total sleeping time increased significantly. Fragmentations of sleep by arousal reactions decreased, time of REM-sleep and non-REM-sleep III and IV increased significantly.