EFFECT OF ETHANOL DRINKING, HANGOVER, AND EXERCISE ON ADRENERGIC ACTIVITY AND HEART-RATE-VARIABILITY IN PATIENTS WITH A HISTORY AT ALCOHOL-INDUCED ATRIAL-FIBRILLATION

To elucidate the mechanism of alcohol-induced atrial fibrillation (AF) we studied the heart rate variability and parameters of the adrenergi c system during alcohol intake, hangover, and exercise in 6 men (mean age 43 years) prone to alcohol-induced AF, together with 6 age-marched controls. The ambulatory (15 hour) electrocardiogram was recorded and blood samples were taken for lymphocytic beta adrenoceptor, plasma ca techolamine, and cyclic adenosine monophosphate (cAMP) measurements be fore and after alcohol intake (blood alcohol 1.5 parts per thousand), during hangover, and after a standardized bicycle exercise test. The b eta-adrenoceptor density in lymphocytes was unchanged in the control g roup after alcohol intake or during hangover. Each of the AF patients had an increase in beta-adrenoceptor density after ethanol drinking (m ean increase 29%, p <0.05). The hangover or exercise beta-receptor val ues did not differ from those in corresponding controls. Plasma adrena line concentration tended to decrease and noradrenaline to increase af ter drinking and during hangover in both groups. Plasma cAMP revels we re lower in patients after drinking than in controls (p <0.05). The ex ercise values of the adrenergic parameters were very similar in AF pat ients whether or not preceded by alcohol. Analysis of ambulatory elect rocardiography showed a very low rate of ectopic beats in both AF pati ents and controls, Analysis of heart rate variability revealed a tende ncy toward an increase in sympathetic/parasympathetic component ratio (low-frequency/high-frequency ratio) in AF patients, but not in contro ls, after ethanol drinking. In conclusion, no signs of arrhythmogenic cardiac disease were detected in patients with AF to explain the tende ncy toward AF. Increases in beta-adrenoceptor density and low-frequenc y/high-frequency ratio during ethanol intoxication in patients with AF suggest an exaggerated sympathetic reaction. (C)1998 by Excerpta Medi co, Inc.