Cardiac pacemakers in the transplanted heart: short term with the biatrialanastomosis and unnecessary with the bicaval anastomosis

Sinus node dysfunction occurs commonly after orthotopic heart transplantati on and may be caused by surgical trauma, ischemia to the sinus node, reject ion, drug therapy, and increasing donor age. In the past, using the standar d biatrial technique described originally by Lower and Shumway, many series have reported permanent pacing in more than 10% of patients. Unlike sinus node dysfunction in nontransplanted patients, which typically worsens with time, sinus node dysfunction in the transplanted heart usually improves ove r a period of weeks to months. Delaying the implantation of a permanent pac emaker may render it unnecessary. The development of the bicaval technique for implantation of the donor heart appears to have decreased even further or even eliminated the need for early permanent pacing. Because sinus node dysfunction in the transplanted heart does not predict subsequent developme nt of atrioventricular (AV) node dysfunction, rate-responsive atrial pacing should be used in the majority of cases. Even after appropriate pacing for sinus node dysfunction, the sinus node may recover and permanent pacing ma y be discontinued. AV conduction abnormalities are far less common and gene rally occur late after transplantation. Dual-chamber pacing is required and permanent pacing should be continued indefinitely. (C) 2000 Lippincott Wil liams & Wilkins, Inc.