EFFICACY OF DIRECT-INJECTION OF ETHANOL INTO THE MYOCARDIUM TO CONTROL ACONITINE-INDUCED VENTRICULAR-TACHYCARDIA IN ANESTHETIZED DOGS

The effect of injecting ethanol directly into the myocardium to contro l aconitine-induced ventricular tachycardia (VT) was evaluated in anes thetized dogs. In 17 dogs, VT was induced by injecting aconitine (1.0 mu g, median dose) directly into the epicardium. After inducing persis tent VT for up to 3 min, 0.6 ml (median volume) of 96% ethanol was inj ected into the same epicardial region. Regular sinus rhythm reappeared in 15 dogs with no change in systolic blood pressure; the other 2 dog s died of ventricular fibrillation (VF). In another 13 dogs, VT was in duced by injecting aconitine directly into the endocardium using a Var iocath needle catheter. After persistent VT for up to 3 min, a regular sinus rhythm was restored in 7 dogs by injecting 2.0 ml (median volum e) of 96% ethanol; the remaining 6 dogs died of VF. Histology showed n o transmural necrosis and the subendocardial necrotic areas were essen tially the same in the dogs that recovered from VT as in those that di ed. There was no statistically significant relationship between doses of ethanol and VT duration. These preliminary results suggest that the injection of ethanol into the myocardium may efficiently terminate VT when other techniques fail.