RECIPIENT-TO-DONOR ATRIOATRIAL CONDUCTION AFTER ORTHOTOPIC HEART TRANSPLANTATION - SURFACE ELECTROCARDIOGRAPHIC FEATURES AND ESTIMATED PREVALENCE

Recipient-to-donor atrioatrial conduction across a suture line has bee n rarely reported after orthotopic heart transplantation, The relation of such conduction to symptomatic arrhythmias and its prevalence are not known. Recipient-to-donor atrioatrial conduction was demonstrated in a 28-year-old woman with paroxysmal supraventricular tachycardia 7 years after orthotopic heart transplantation. Atrial tachycardia in th e recipient atria conducted 2:1 to the donor atria and was eliminated by radiofrequency catheter ablation of a left-sided atrioatrial electr ical connection. The electrocardiogram at rest and during exercise, re corded before ablation of the recipient-to-donor connection, showed fr equent atrial premature complexes, with variable coupling to the prece ding sinus beats, and a change in P-wave morphology during exercise, w hich reverted to normal during the recovery period. These findings wer e eliminated by ablation of the recipient-to-donor connection. To dete rmine the prevalence of recipient-to-donor atrioatrial conduction late after transplantation, we evaluated the exercise electrocardiograms o f 50 subjects > 5 years after heart transplantation for these features of recipient-to-donor conduction. At least 1 feature was present in 5 subjects, and both were present in 1 subject. Electrical conduction c an occur across surgical suture lines in the atria. Recipient-to-donor atrioatrial conduction may occur in less than or equal to 10% of pati ents sate after heart transplantation, It is a potential cause of arrh ythmias that can be effectively treated with radiofrequency catheter a blation. (C) 1998 by Excerpta Medica, Inc.