Clinical evaluation of the enhancement of vagal tone in acute myocardial infarction by edrophonium hydrochloride: effects on ventricular arrhythmias, His bundle electrography, and left ventricular function

Vanillylmandelic acid protects against reperfusion injury in an experimental animal model of myocardial infarction

Vanillylmandelic acid, a catecholamine end-metabolite, has been shown to have several biological properties in previous studies, despite considered biologically inactive. We examined the potential effects of vanillylmandelic acid on the ischemic heart following myocardial infarction and reperfusion on a rat model. Thirty-four female Wistar rats were randomized into two groups, control and experimental. They were anesthetized and subjected to myocardial infarction through left anterior descending artery ligation. A previously studied dose of vanillylmandelic acid (10 mg/kg) was administered and the following parameters were studied during ischemia and reperfusion: a) mortality b) severity of ventricular tachyarrhythmias c) premature ventricular contractions and d) heart rate. Administration of vanillymandelic acid significantly reduced the severity of ventricular tachyarrhythmias and mortality rate during reperfusion, while it did not affect any other of the parameters studied. In conclusion, reperfusion injury was blunted through vanillylmandelic acid administration, which seems to be mediated by parasympathetic activation.

Verapamil in the treatment of PSVT

Verapamil is considered by many investigators to be the drug of choice for the acute management of uncomplicated PSVT. Several clinical investigators have demonstrated termination of PSVT in more than 90% of their patients within minutes following IV drug administration. The incidence of reported severe adverse reactions has been less than 1%. PSVT may be complicated by underlying heart disease, or by antegrade accessory pathway conduction in individuals with pre-excitation syndrome. Such conditions, or the prior use of beta-blocking agents, may contraindicate the use of verapamil. However, the history of recent myocardial ischemia or the prior use of digitalis does not appear to contraindicate verapamil therapy. Guidelines for the emergency management of the patient in PSVT are presented.