Author + information
- Received August 31, 1983
- Revision received November 28, 1983
- Accepted December 9, 1983
- Published online May 1, 1984.
- Edward N. Shen, MD, FACC1,2,
- Ruey J. Sung, MD, FACC*,1,
- Fred Morady, MD, FACC1,
- Alan B. Schwartz, MD1,
- Melvin M. Scheinman, MD, FACC1,
- Lorenzo Dicarlo, MD1 and
- William Shapiro, MD1
- ↵*Address for reprints: Ruey J. Sung. MD, Director, Cardiac Electro-physiology, 5G1, Division of Cardiology, San Francisco General Hospital Medical Center, San Francisco, California 94110.
Electrophysiologic and hemodynamic studies were performed before and after intravenous infusion of a new antiarrhythmic agent, propafenone, in 28 patients with recurrent ventricular tachycardia. Propafenone was given at a loading dose of 2 mg/kg in all patients. Subsequently, group A, the first 14 patients, received 1 mg/min and group B, the second 14 patients, received 2 mg/min continuous infusion. Propafenone exerted no effect on sinus nodal recovery time and sinoatrial conduction time, but significantly prolonged atrioventricular (AV) nodal and His-Purkinje conduction time and the QRS duration (respectively, 95 ± 19, 48 ± 10 and 120 ± 23 ms before, and 110 ± 28, 53 ± 10 and 135 ± 27 ms after; p < 0.001). Propafenone did not change the mean arterial blood pressure but slightly increased right atrial, pulmonary artery and capillary wedge pressures resulting in mild depression of the cardiac index (2.6 ± 0.8 liters/min per m2 before and 2.3 ± 0.7 liters/min per m2 after; p < 0.001). None of the patients were symptomatic from these changes.
In group A, propafenone did not affect the inducibility of ventricular tachycardia except for one patient whose arrhythmia was sustained before and became nonsustained after propafenone. In group B, sustained ventricular tachycardia became noninducible in three patients and nonsustained in two patients, and nonsustained ventricular tachycardia became noninducible in one patient after propafenone. Therefore, an appropriate loading dose of intravenous propafenone such as 2 mg/kg followed by 2 mg/min infusion may be given safely and may suppress ventricular tachycardia. Propafenone may be a useful addition to currently available antiarrhythmic agents.
- Received August 31, 1983.
- Revision received November 28, 1983.
- Accepted December 9, 1983.
- American College of Cardiology Foundation