SUMMARYIn order to assess potential improvement in abnormal left ventricular (LV) wall motion, eighteen subjects sixteen with obstructive coronary artery disease and LV asynergy and two with no evidence of organic heart disease were studied by cardiac catheterization and cineangiography. Ventriculograms were performed at rest and during a constant infusion of l-epinephrine (EPI) at 1-4 ,gg/min after an average of nine minutes steady state. EPI infusion induced augmentation of LV contraction pattern in both normal subjects and in all normal zones in the sixteen subjects with asynergy, and in no instance was contraction in a normal zone rendered abnormal. Eleven of sixteen patients showed improved contraction in previously asynergic areas, two of whom also demonstrated paradoxical motion in an abnormal zone. Of a total of forty-four resting asynergic zones, twenty-three exhibited an improved contraction pattern with EPI, one showed depressed contraction, two demonstrated both an increase and deterioration in the same zone (paradoxical motion), and eighteen showed no change. Quantitative motion analysis generally corroborated these qualitative ventriculographic observations. Heart rate, LV systolic pressure and LV end-diastolic pressure increased slightly with EPI, but were not significantly changed from control values. While there was wide variation in end-diastolic volume in the subjects with asynergy, EPI resulted in an increase in both stroke volume and ejection fraction, the latter significantly (P < 0.05). In the four subjects who subsequently underwent aneurysmectomy, preoperative lack of improvement with EPI correlated with a pathologic diagnosis of fibrosis. Other than angina pectoris of brief duration in two subjects, EPI provoked no untoward reactions, arrhythmias or complications. It is concluded that LV motion abnormalities can be improved or changed in certain cases by the inotropic stimulus of EPI, suggesting residual contractile ability; the agent may differentiate between zones of potentially functional cardiac muscle and frank fibrosis.

The exposure of ventricular ectopic activity (VEA) by maximal exercise testing and 24-hour ambulatory monitoring was compared in 100 unselected patients with coronary heart disease. The arrhythmia was noted with exercise in 56 patients and with monitoring in 88. Repetitive forms such as couplets and ventricular tachycardia were found to be twice as frequent (40 vs. 20) with monitoring than with exercise. Patients with prior myocardial infarction had more frequent ventricular ectopic activity of a more advanced grade with both exercise and monitoring than patients with angina pectoris. Exercise exposed the grades of ectopic activity that recurred during two or more hours of the monitoring session. Of seven patients with ventricular tachycardia on exercise only four exhibited this grade with monitoring. It may be that these two methods divulge different information regarding the electrophysiologic state of the myocardium.

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