Effect of Ethanol in Experimental Auricular and Ventricular Arrhythmias

Abstract

In view of a recent report that ethanol converted strophanthidin-induced ventricular tachycardia to normal sinus rhythm (1), it was of interest to investigate the effect of ethanol in other experimental cardiac arrhythmias, the underlying mechanisms of which are seemingly different from those provoked by digitalis.Atrial fibrillation was produced according to the method described by Schallek (2) in 6 pentobarbitaliz ed (30 mg/kg i.v.) dogs by the topical application of 5% acetylcholine on the sinus node.Ventricular arrhythmias were produced in another 10 dogs according to the method of Harris and Kokernot (3) which has been described in detail in a previous communication (4). Anterior descending branch of the left coronary artery was ligated in 2 stages under pentobarbital anaesthesia . Electrocardio gram of the dogs in the unanaesthetized state on the following post-operative day showed complete dissocia tion of auricular and ventricular beats with the development of ectopic ventricular techycardia.Ethanol, 500 mg/kg, was diluted to 20 ml with isotonic saline and given intravenously over a period of 10 minutes.Same dose was repeated after every half an hour, if necessary, upto a maximum of 3 injections.A total of nine blood samples were withdrawn from the above dogs in order to find out the blood con centration of alcohol at the time of its peak cardiac effects. The method of Hansen, as described in detail by Glick (5), was followed in these analyses.In acetylcholine-induced atrial fibrillation, 500 mg/kg of ethanol caused a 45 .2 + 2.1 % (Mean + S.E.) reduction in the duration of arrhythmia. In ectopic ventricular tachycardia, ethanol reduced both the total heart rate and ectopic ventricular beats in all the experiments (Table 1). In two dogs, there was complete suppression of ectopic beats

Effects of alcohol on atrial fibrillation: myths and truths

“…Using canine models, Nguyen et al (1987) observed that alcohol caused vasodilation, negative inotropic effect, and atrial antiarrhythmic effect. Madan and Gupta (1967) also observed alcohol atrial and ventricular antiarrhythmic effect in canine models.…”

Ethanol as an arrhythmogen and an antiarrhythmic agent with reoxygenation arrhythmias of cultured heart cells

“…Moreover, the ad libatum consumption of 10% ethanol during induced audiogenic stress partially blocked stress-related biochemical changes and completely inhibited cardiac hypertrophy [19]. The acute administration of ethanol to anesthetized dogs is capable of suppressing ventricular arrhythmias produced by coronary ligation, cardiac glycoside intoxication, or elevation of the fibrillation threshold to electrical stimulation [20][21][22][23]. A similar elevation of the atrial fibrillation threshold has also been demonstrated [24].…”

Ethanol protects against lysophosphatidylcholine-induced uncoupling of cardiac cell pairs

“…In particular, Gilmour et al [16] demonstrated in an anesthetized dog model, that ethanol blunted electrocardiogram changes induced by ischemia and the incidence of ventricular fibrillation induced by a rapid stimulation. Anti-fibrillatory effects of ethanol have also been reported [23,28]. Finally, cardio-protective effects (i.e., infarct size) of ethanol during ischemia and reperfusion/reoxygenation have been shown in anesthetized guinea pig and rat models [2,30], isolated perfused rat hearts [2] and cultures of neonate rat cardiomyocytes [40].…”

“…It was shown that acute ethanol administration suppresses ventricular tachyarrhythmias following coronary artery ligature or digitalis intoxication [23,29] and increases ventricular and auricular fibrillation thresholds [21,22]. In particular, Gilmour et al [16] demonstrated in an anesthetized dog model, that ethanol blunted electrocardiogram changes induced by ischemia and the incidence of ventricular fibrillation induced by a rapid stimulation.…”