Electrocardiographic Findings in Cardiac Transplantation

This paper outlines the electrocardiographic course of a 46-year-old recipient of a cardiac transplant in whom direct myocardial leads were implanted. There was one episode of decreased QRS voltage with an intraventricular conduction delay, suggestive of an acute immunologic rejection. On one occasion bradycardia occurred, and this was treated by ventricular pacing. There was also an episode of supraventricular tachycardia. Vagotonic maneuvers or agents would not have been appropriate treatment for this arrhythmia. In the presence of both donor and recipient P waves, the interpretation of some of the arrhythmias was difficult. Since the QRS voltage is important in diagnosing early rejection, great care was taken in accurately standardizing the electrocardiogram and in reproducibly placing electrocardiographic leads. The myocardial leads were found to reflect voltage changes more clearly than surface leads. The presence of myocardial wires also proved convenient for pacing. The use of a right atrial recording electrode is recommended for the diagnosis of complex arrhythmias. This will permit more accurate identification of donor and recipient P waves.