title: Ventricular function and long-term pacing in children with congenital complete atrioventricular block.
abstract: OBJECTIVE
  To determine the sequela of right ventricular pacing in children with congenital complete atrioventricular block.
  
  
  BACKGROUND
  Pacing is a well-accepted therapy for patients with congenital complete atrioventricular block. The long-term sequela of right ventricular pacing in this population has not been well described.
  
  
  METHODS
  We performed a cohort study on all patients with congenital complete atrioventricular block who underwent pacemaker implantation at our institution from 1972 to 2004. Patients with associated congenital heart disease or ventricular dysfunction prior to pacemaker implantation were excluded.
  
  
  RESULTS
  A total of 63 patients were included in the study. The median age at pacemaker implantation was 6.5 years, with an average follow-up of 9.9 years. The cumulative dysfunction free survival at 20 years was 92%. In total, four patients (6%) were noted to develop LV dysfunction an average of 15.1 years after pacemaker implantation. Of 30 patients who were paced for >10 years, only three (10%) developed echocardiographic evidence of LV dysfunction. Right ventricular apex pacing and prolonged QRS duration were found to be predictive of decreased long-term LV systolic function (P < 0.05).
  
  
  CONCLUSIONS
  Left ventricular dysfunction in patients with congenital complete atrioventricular block is a rare finding, even in those who have been paced for more than 10 years. Right ventricular apex pacing and prolonged QRS duration may be associated with decreased ventricular function over time. At this time, with such a low incidence of cardiac dysfunction, right ventricular pacing should be considered an acceptable first-line therapy in this population.
authors: Section of Pediatric Cardiology, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas 77030, USA. jjkim@texaschildrenshospital.org
authors: Jeffrey J
authors: JJ
authors: Kim
authors: Richard A
authors: RA
authors: Friedman
authors: Benjamin W
authors: BW
authors: Eidem
authors: Bryan C
authors: BC
authors: Cannon
authors: Gaurav
authors: G
authors: Arora
authors: E O'Brian
authors: EO
authors: Smith
authors: Arnold L
authors: AL
authors: Fenrich
authors: Naomi J
authors: NJ
authors: Kertesz
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002304:Cardiac Pacing, Artificial / Q000706:statistics & numerical data*; D009202:Cardiomyopathies / Q000000981:diagnostic imaging / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006327:Heart Block / Q000151:congenital* / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012044:Regression Analysis; D012307:Risk Factors; D016019:Survival Analysis; D013781:Texas / Q000453:epidemiology; D013995:Time; D014463:Ultrasonography; D016276:Ventricular Function