Study Objective: To evaluate the hemodynamic effects of the antiarrhythmic drug, encainide, in patients with severe chronic heart failure.
Design: Unblinded, before-after study.
Setting: Referral center for patients with heart failure.
Patients: Thirty patients with severe chronic heart failure and a left ventricular ejection fraction less than 40%.
Interventions: Invasive hemodynamic measurements were done (using a balloon-tipped thermodilution catheter) before and for 3 hours after a single oral dose of 50 mg of encainide.
Measurements and Main Results: Ninety to one hundred and twenty minutes after its administration, encainide produced a significant deterioration in cardiac performance, as reflected by a fall in cardiac index from 2.3 to 1.8 L/min·m2 body surface