title: Late pacemaker requirement after pediatric orthotopic heart transplantation may predict the presence of transplant coronary artery disease.
abstract: BACKGROUND
  Few data are available regarding pacemaker implantation after pediatric orthotopic heart transplantation. The purpose of this study was to assess the incidence, indications and associations with regard to pacemaker placement in children who have undergone orthotopic heart transplantation.
  
  
  METHODS
  We performed a retrospective study of all patients undergoing orthotopic heart transplantation at our institution from October 1984 to March 2001. Data obtained included demographics, indications for pacemaker, presence of transplant coronary artery disease and long-term follow-up. Patients were divided into: Group 1, patients requiring a pacemaker within 3 months of transplantation; and Group 2, patients requiring a pacemaker beyond 3 months.
  
  
  RESULTS
  Pacemakers were required in 7 of 106 (6.6%) transplant recipients. Pacing indications for patients in Group 1 (n = 2) were persistent bradycardia with pause-related ventricular arrhythmia and atrial flutter with resultant sinus pauses of up to 4 seconds. In Group 2 patients (n = 5), indications for pacing were high-grade atrioventricular (AV) block in 1 patient and episodic sinus pauses up to 3.3 seconds associated with syncope/dizziness in the remaining 4 patients. All patients in Group 2 had transplant coronary disease diagnosed within 1 year of pacemaker implantation. All had resolution of symptoms and no complications after implantation.
  
  
  CONCLUSIONS
  Pacemakers are infrequently required after cardiac transplantation in children. Despite not meeting classic symptomatic sinus bradycardia criteria, pacemaker placement should be considered post-transplantation in patients with episodic sinus pauses and dizziness or syncope. Patients who present with the aforementioned symptoms or high-grade AV block should be evaluated closely for the presence or development of transplant coronary artery disease, as it may be their first symptom.
authors.affiliation: Division of Cardiology, Section of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas 77030, USA. bcannon@bcm.tmc.edu
authors.forename: Bryan C
authors.initials: BC
authors.lastname: Cannon
authors.forename: Susan W
authors.initials: SW
authors.lastname: Denfield
authors.forename: Richard A
authors.initials: RA
authors.lastname: Friedman
authors.forename: Arnold L
authors.initials: AL
authors.lastname: Fenrich
authors.forename: W Jeffrey
authors.initials: WJ
authors.lastname: Dreyer
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Towbin
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Kertesz
mesh_terms: D001919:Bradycardia / Q000175:diagnosis / Q000517:prevention & control; D002648:Child; D002675:Child, Preschool; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000517:prevention & control*; D016027:Heart Transplantation / Q000379:methods*; D006801:Humans; D007223:Infant; D010138:Pacemaker, Artificial; D011183:Postoperative Complications / Q000517:prevention & control*; D012189:Retrospective Studies; D013997:Time Factors