title: Thromboprophylaxis for atrial arrhythmias in congenital heart disease: A multicenter study.
abstract: BACKGROUND
  There is a paucity of data to guide decisions regarding thromboprophylaxis for atrial arrhythmias in congenital heart disease.
  
  
  METHODS
  A retrospective multicenter cohort study enrolled patients with documented sustained atrial arrhythmias and congenital heart disease from 12 North American centers to quantify thromboembolic and bleeding rates associated with antiplatelet and anticoagulation therapy, and explore associated factors. A blinded committee adjudicated all qualifying arrhythmias and outcomes.
  
  
  RESULTS
  A total of 482 patients, 45.2% female, age 32.0±18.0years, were followed for 11.3±9.4years since the qualifying arrhythmia. Antiplatelet therapy was administered to 37.8%, anticoagulation to 54.4%, and neither to 7.9%. Congenital heart disease complexity was simple, moderate, and severe in 18.5%, 34.4%, and 47.1%, respectively. Freedom from thromboembolic events was 84.7±2.7% at 15years, with no difference between anticoagulation versus antiplatelet therapy (P=0.97). Congenital heart disease complexity was independently associated with thromboembolic events, with rates of 0.00%, 0.93%, and 1.95%/year in those with simple, moderate, and severe forms (P<0.001). CHADS2and CHA2DS2-VASc scores were not predictive of thromboembolic risk. Annualized bleeding rates with antiplatelet and anticoagulation therapy were 0.66% and 1.82% (P=0.039). In multivariable analyses, anticoagulation [hazard ratio (HR) 4.76, 95% CI (1.05-21.58), P=0.043] and HAS-BLED score [HR 3.15, 95% CI (1.02, 9.78), P=0.047] were independently associated with major bleeds.
  
  
  CONCLUSIONS
  Current management of atrial arrhythmias in congenital heart disease is associated with a modest rate of thromboembolic events, which is predicted by disease complexity but not CHADS2/CHA2DS2-VASc scores. HAS-BLED score is applicable to the congenital population in predicting major bleeds.
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada; Montreal Health Innovations Coordinating Center (MHICC), Montreal, Quebec, Canada. Electronic address: paul.khairy@umontreal.ca.
authors: Paul
authors: P
authors: Khairy
authors: University of California, Los Angeles, CA, USA.
authors: Jamil
authors: J
authors: Aboulhosn
authors: Oregon Health and Science University, Portland, OR, USA.
authors: Craig S
authors: CS
authors: Broberg
authors: The Wisconsin Adult Congenital Heart (WAtCH) Program, Medical College of Wisconsin, Milwaukee, WI, USA.
authors: Scott
authors: S
authors: Cohen
authors: Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.
authors: Stephen
authors: S
authors: Cook
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Annie
authors: A
authors: Dore
authors: Stanford University, Palo Alto, CA, USA.
authors: Susan M
authors: SM
authors: Fernandes
authors: Hôpital Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.
authors: Anne
authors: A
authors: Fournier
authors: University of Colorado Denver, Aurora, CO, USA.
authors: Joseph
authors: J
authors: Kay
authors: Montreal Health Innovations Coordinating Center (MHICC), Montreal, Quebec, Canada.
authors: Sylvie
authors: S
authors: Levesque
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Laurent
authors: L
authors: Macle
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: François
authors: F
authors: Marcotte
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Blandine
authors: B
authors: Mondésert
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: François-Pierre
authors: FP
authors: Mongeon
authors: Boston Adult Congenital Heart Service, Boston Children's Hospital and Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Alexander R
authors: AR
authors: Opotowsky
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Anna
authors: A
authors: Proietti
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Lena
authors: L
authors: Rivard
authors: Milton S. Hershey Medical Center, Pennsylvania State University, Hershey, PA, USA.
authors: Jennifer
authors: J
authors: Ting
authors: Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors: Bernard
authors: B
authors: Thibault
authors: Nationwide Children's Hospital, Ohio State University, Columbus, OH, USA.
authors: Ali
authors: A
authors: Zaidi
authors: Co-PI, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors: Robert
authors: R
authors: Hamilton
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications* / Q000188:drug therapy; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006330:Heart Defects, Congenital / Q000150:complications* / Q000188:drug therapy; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000925:Anticoagulants
keywords: Anticoagulation; Antiplatelet therapy; Atrial tachycardia; Bleeding; Congenital heart disease; Thromboembolic event