A study of the acute electrophysiological and cardiovascular action of disopyramide in man.

The acute electrophysiological and hemodynamic effects of intravenous disopyramide (1.5 mg/kg body weight) were studied in 12 patients with suspected coronary artery disease. Plasma levels of disopyramide were monitored. Disopyramide delayed conduction within the His-Purkinje system and increased the effective refractory period of the atrium. Conduction within the AV node and its refractory period, however, was not significantly altered by the drug. The corrected Q-T interval was significantly increased. Disopyramide increased systemic arterial pressure and slightly raised the left ventricular end diastolic pressure. Heart rate, cardiac and stroke index were unaltered. Peak mean levels of disopyramide were reached 5 minutes after the injection of the drug.