Beneficial effect of morphine on the threshold of electrical fibrillation of the ventricle. Experimental study

: The action of 2-3 mg/kg of morphine on the threshold of electrical fibrillation of the ventricle (TVF) in anesthetized dogs has been studied. The basal TVF was 10.5 +/- 4.9 mA, increased to 20.2 +/- 7.7 mA (P 0.005) with the administration of this drug. Comparatively, the effect of morphine on the TVF is similar to that of propranolol and bretilium and more effective than procainamide. The mechanism by which it acts is not well known. Perhaps it is due to a homogenization of refractory periods in the ventricle as well as a possible morphine-catacholamine interaction. Morphine in dosis of 2-3 mg/kg could occupy a place among the antiarrhythmic drugs of choice with antifibrillatory action, with important usefulness in the field of anestesiology of cardiopaths.