title: Inducibility of intra-atrial reentrant tachycardia after the first two stages of the Fontan sequence.
abstract: OBJECTIVE
  We sought to examine the incidence and possible factors for inducible intra-atrial reentrant tachycardia (IART) in a group of patients after two stages of the Fontan sequence but before the operation.
  
  
  BACKGROUND
  Intra-atrial reentrant tachycardia occurs in 10% to 40% of patients after the Fontan operation. No data are available regarding the potential for IART after the first two stages of the Fontan sequence but before the operation.
  
  
  METHODS
  The IART induction protocol included programmed extrastimulation and rapid atrial pacing, with and without isoproterenol.
  
  
  RESULTS
  The median age of the study group (n = 44, 27 males) was 1.7 years (range 1.2 to 5.2). Forty patients were in sinus rhythm. Twelve patients (27%) had inducible, sustained (>1 min) IART. Three patients (8%) had inducible, nonsustained IART. Bivariate analysis revealed that patients with sustained IART were significantly older at their second operation (median 0.54 vs. 0.40 years, p = 0.05). Multivariate logistic modeling revealed that older age (> or =0.55 years) at the second palliative operation (p = 0.04), older age (> or =1.95 years) at evaluation before the Fontan sequence (p = 0.04) and female gender (p = 0.03) were independently associated with sustained IART. A trend toward a greater frequency of sustained IART was seen in those patients with moderate or severe atrioventricular valve regurgitation (p = 0.07) and in those with resection of the atrial septum (p = 0.06).
  
  
  CONCLUSIONS
  The rate of inducible, sustained IART in a group of patients before the Fontan operation is 27% and is associated with older age at the time of second-stage palliation, older age at pre-Fontan evaluation and female gender.
authors.affiliation: University of Michigan Congenital Heart Center and Department of Pediatrics, University of Michigan Health Systems, Ann Arbor 48109-0204, USA.
authors.forename: I H
authors.initials: IH
authors.lastname: Law
authors.forename: P S
authors.initials: PS
authors.lastname: Fischbach
authors.forename: C
authors.initials: C
authors.lastname: Goldberg
authors.forename: R S
authors.initials: RS
authors.lastname: Mosca
authors.forename: E L
authors.initials: EL
authors.lastname: Bove
authors.forename: T R
authors.initials: TR
authors.lastname: Lloyd
authors.forename: A P
authors.initials: AP
authors.lastname: Rocchini
authors.forename: M
authors.initials: M
authors.lastname: Dick
mesh_terms: D000293:Adolescent; D002304:Cardiac Pacing, Artificial; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D018729:Fontan Procedure; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011183:Postoperative Complications / Q000175:diagnosis*; D012086:Reoperation; D012307:Risk Factors; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis*