title: Catheter ablation of atrial arrhythmias after cardiac transplantation: findings at EP study utility of 3-D mapping and outcomes.
abstract: BACKGROUND
  Management of atrial arrhythmias (AA) in orthotopic heart transplant (OHT) patients is challenging.
  
  
  OBJECTIVE
  The purpose of this study was to define the mechanisms of these arrhythmias and to evaluate the role of ablation.
  
  
  METHODS
  Patients with OHT referred for ablation of AA from 1999 to 2011 were included (n = 15). Entrainment and anatomic 3-D mapping were utilized to identify AA mechanism and guide ablation.
  
  
  RESULTS
  The median time from OHT to ablation was 8 years (range: 1 month-16 years). AA types included 1 (7%) AVNRT, 5 (33%) cavotricuspid isthmus (CTI) dependent donor atrial flutter (AFl), 3 (20%) non-CTI-dependent donor AFL (n = 3), focal atrial tachycardia (AT) (n = 2) and in 4 (27%) recipient to donor atria conduction (RDC) that involved the right atrial anastomosis in 3 and left atrial anastamosis in 1 patient. In RDC tachycardia, ablation was performed at the site of earliest donor atrial activation on the suture line. AA in the recipient atria were not targeted. This resulted in acute success in all cases. In most patients 12/15 (80%) only right atrial ablation was necessary. Regardless of surgical technique (bicaval vs biatrial) right-sided AA was most common. Acute success occurred in 14/15 (93%) patients and 3/15 (20%) required repeat Abl for recurrence. There were no major complications.
  
  
  CONCLUSIONS
  AA after OHT are most commonly due to atrial macroreentry, but focal arrhythmias and RDC atrial conduction also occur. Ablation of organized AA is usually successful with low risk, warranting early consideration in preference to medical treatment.
authors: Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors: Eyal
authors: E
authors: Nof
authors: William G
authors: WG
authors: Stevenson
authors: Laurence M
authors: LM
authors: Epstein
authors: Usha B
authors: UB
authors: Tedrow
authors: Bruce A
authors: BA
authors: Koplan
mesh_terms: D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D001282:Atrial Flutter / Q000209:etiology / Q000601:surgery; D017115:Catheter Ablation; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006325:Heart Atria; D016027:Heart Transplantation; D006801:Humans; D008875:Middle Aged; D011183:Postoperative Complications / Q000601:surgery; D013610:Tachycardia / Q000209:etiology / Q000601:surgery; D013997:Time Factors