LACK OF EFFECT OF PROCAINAMIDE ON VENTRICULAR FUNCTION OF CONSCIOUS DOGS

The effect of continuous infusion of 1 mg./ kg./min. of procainamide for 30 minutes on ventricular function was studied in 5 conscious dogs. An electromagnetic flowmeter probe was placed around the pulmonary artery, and catheters were positioned in the left atrium and superior vena cava. Two weeks later ventricular function curves were determined by rapidly infusing Tyrode's solution in the catheter in the superior vena cava while right and left atrial pressure, mean arterial pressure, heart rate, mean cardiac output and pulsatile pulmonary artery flow were recorded. Ventricular function curves were repeated after 25 minutes of procainamide infusion. There was no significant change in the average resting mean arterial pressure, heart rate, ventricular output, or stroke volume before or after the administration of procainamide. The average plateau of the ventricular output curve was 296 ml./min./kg. (± 14.9 S.D.) during the control studies and 299 ml./min./kg (± 13.1 S.D.) during the infusion of procainamide. Thus, there was no statistically significant change observed in either the resting hemodynamics or the ventricular function curves resulting from the continuous intravenous infusion of procainamide. © 1969.