Acute effects of alcohol, beta blockade, and their combination on left ventricular function and hemodynamics in normal man

Twenty-three healthy males, aged 23 to 62 years, were examinedby M-mode echocardiography and systolic time intervals for 3h after (1) ethanol 1 g/kg by mouth taken over 60 minutes; (2)atenolol 100 mg by mouth; (3) ethanol (1 g/kg) + atenolol (100mg). The peak mean blood ethanol (± s.e.) was 112 ±4mg/100 ml in test 1 and 104 ± 7 mg/100 ml in test 3.During increasing blood ethanol, heart rate (HR), systolic bloodpressure (BP), cardiac output (CO) and echocardiographic indicesof left ventricular (LV) function were significantly augmented,while total peripheral resistance (TPR) decreased. During decliningblood ethanol, systolic BP, L V end-diastolic and end-systolicdiameters, stroke volume (SV) and circumferential wall stresswere significantly reduced; echocardiographic indices of LVfunction were unaltered, but the pre-ejection period/LV ejectiontime ratio was increased, Atenolol decreased llR, systolic BP,SV, CO, and all estimates of LV function, but increased TPR.Ethanol + atenolol tended to cause smaller depressions in theindices of LV function than did atenolol alone, in spite ofsimilar plasma atenolol concentrations (n = 6). It is concludedthat ingestion of modest doses of ethanol evokes vasodilationand enhances LV function during increasing blood ethanol, andreduces LV preload and afterload during decreasing blood ethanolwithout impairing contractility. Social drinking and beta blockadeseem not to have any harmful acute combined effects on the heartand circulation, at least in normal subjects.