Acute effects of alcohol on left ventricular dynamics during isometric exercise in normal subjects

Abstract
The aim of this study was to assess whether drinking social amounts of alcohol impairs myocardial contractility in normal humans. To that end, 17 healthy volunteers performed isometric handgrip exercise before and 60 minutes after an intake of 1 g/kg body weight of ethanol within 60 minutes. Left ventricular M‐mode echocardiogram, systolic time intervals, and sphygmomanometric arterial blood pressure were recorded before and at the end of 4‐min handgrip at 30% of maximum voluntary contraction. The blood ethanol concentration (mean±SD) was 24.4±2.0 mmol/liter. At rest, ethanol increased heart rate (p>0.05) and decreased left ventricular end‐diastolic diameter (p>0.05), end‐systolic diameter (p>0.01), and circumferential systolic wall stress (p>0.05). The indices of left ventricular performance were unchanged except for the maximum circumferential fiber shortening velocity which was increased after ethanol (p>0.001). The cardiac response to isometric exercise was similar before and after ethanol except that the handgrip‐induced rise in systolic wall stress was smaller postingestion (p>0.05). This study does not support the view that drinking small to moderate amounts of alcohol brings about myocardial depression in normal humans. Although preload, afterload, and heart rate were altered by ethanol at rest>d>Myocardial contractility was not impaired even during the afterload stress imposed by isometric exercise.