Nocturnal angina and sleep

Abstract

1. 1. Nocturnal sleep and electro cardiographic patterns were continously investigated in 20 male patients suffering from nocturnal angina attacks. Sleep pattern was severely disturbed regardless of the presence of ischemic episodes. Sleep Time was reduced because of a large Awakening Time and an Early Final Awakening. Stages 1 and 2 were increased and stages 3, 4 and, less markedly, REM were reduced. 2. 2. Ischemic episodes were more frequently observed between 24:00 and 04:00 without any significant relationship to the sleep stages, thus suggesting the influence of a cronobiologic factor on the distribution of ischemic attacks during the night. 3. 3. Ischemic episodes observed during the hemodynamic monitoring did not show any significant relation to the increase of myocardial oxygen consumption. This observation, together with the lack of relation between REM sleep and ischemic episodes during the night, seem to support the hypothesis of a reversible coronary spasm in the pathogenesis of nocturnal angina.