Cardiovascular time course after digoxin administration in left ventricular dysfunction after coronary artery bypass grafting.

Intravenous digoxin, 1 mg, was administered over 8 hours to 10 cardiac patients with left ventricular (LV) dysfunction after coronary artery bypass grafting. The cardiovascular effects of digoxin were monitored over 20 hours by indwelling pulmonary artery and radial artery lines and were compared with those of a control group of 10 patients who had normal postoperative LV function. Digoxin administration produced an increased cardiac index and mean arterial blood pressure within 2 hours. Within 4 hours after digoxin administration pulmonary artery wedge pressure in patients receiving digoxin was significantly lower than in control patients. At 16 hours there was a significant increase in both the LV stroke work and LV stroke work index in patients receiving digoxin vs control patients. Two patients receiving digoxin and 3 control patients had changes in cardiac rhythm during the study. Thus, digoxin can be safely administered to postoperative patients with LV dysfunction and is an acceptable inotropic agent.