Permanent pacing for late-onset atrioventricular block in patients with heart transplantation: a single center experience.

INTRODUCTION: The incidence, mechanisms, clinical associations, and outcomes in patients with late-onset (>3 months) atrioventricular (AV) block following heart transplantation are not well known. This study will characterize late-onset AV block following cardiac transplantation.
METHODS: We retrospectively reviewed our databases to identify patients who required pacemakers for late-onset AV block postheart and heart-lung transplantation from January 1990 to December 2007. Orthotopic heart and heart-lung transplantation were separately analyzed.
RESULTS: This study included 588 adults who received cardiac transplants over a 17-year period at our center (519 orthotopic, 64 heart-lung transplants, and five heterotopic heart transplants). Of the 519 patients with orthotopic heart transplant, 39 required pacing (7.5%), 17 (3.3%) within 3 months posttransplant, 11 (2.1%) for late-onset sinus node dysfunction (SND), 11 (2.1%) for late-onset AV block. Also, five patients (7.8%) out of 64 heart-lung transplants required pacemakers, two (3.1%) for late-onset SND, three (4.7%) for late-onset AV block. None of the five patients who underwent heterotopic transplant required cardiac pacing prior to or posttransplant.
CONCLUSIONS: Late-onset AV block occurs in 2.4% of patients with orthotopic heart transplant or heart-lung transplant. AV block is predominantly intermittent and, often, does not progress to permanent AV block. There are no predictable factors for its onset. ©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.