Thromboembolic Risk After Atriopulmonary, Lateral Tunnel, and Extracardiac Conduit Fontan Surgery

J Am Coll Cardiol. 2019 Aug 27;74(8):1071-1081. doi: 10.1016/j.jacc.2019.06.051.

Abstract

Background: Thromboembolic events contribute greatly to morbidity and mortality following Fontan surgery for univentricular hearts.

Objectives: This study sought to evaluate the effect of type of Fontan surgery on thromboembolic risk.

Methods: A North American multicenter retrospective cohort study enrolled 522 patients with Fontan palliation consisting of an atriopulmonary connection (APC) (21.4%), lateral tunnel (LT) (41.8%), or extracardiac conduit (EC) (36.8%). Thromboembolic complications and new-onset atrial arrhythmia were reviewed and classified by a blinded adjudicating committee. Thromboembolic risk across surgical techniques was assessed by multivariable competing-risk survival regression.

Results: Over a median follow-up of 11.6 years, 10- and 20-year freedom from Fontan conversion, transplantation, or death was 94.7% and 78.9%, respectively. New-onset atrial arrhythmias occurred in 4.4, 1.2, and 1.0 cases per 100 person-years with APC, LT, and EC, respectively. APC was associated with a 2.82-fold higher risk of developing atrial arrhythmias (p < 0.001), with no difference between LT and EC (p = 0.95). A total of 71 thromboembolic events, 32 systemic and 39 venous, occurred in 12.8% of subjects, for an overall incidence of 1.1%/year. In multivariable analyses, EC was independently associated with a lower risk of systemic (hazard ratio [HR]: 0.20 vs. LT; 95% confidence interval [CI]: 0.04 to 0.97) and combined (HR: 0.34 vs. LT; 95% CI: 0.13 to 0.91) thromboembolic events. A lower incidence of combined thromboembolic events was also observed with antiplatelet agents (HR: 0.54; 95% CI: 0.32 to 0.92) but not anticoagulation (p = 0.53).

Conclusions: The EC Fontan was independently associated with a lower thromboembolic risk after controlling for time-varying effects of atrial arrhythmias and thromboprophylaxis.

Keywords: Fontan procedure; atrial arrhythmia; single ventricle; thromboembolism; thromboprophylaxis univentricular heart.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Arrhythmias, Cardiac / diagnosis
  • Arrhythmias, Cardiac / epidemiology
  • Arrhythmias, Cardiac / surgery
  • Child
  • Child, Preschool
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Fontan Procedure / adverse effects
  • Fontan Procedure / trends*
  • Heart Defects, Congenital / diagnosis
  • Heart Defects, Congenital / epidemiology*
  • Heart Defects, Congenital / surgery*
  • Humans
  • Male
  • Postoperative Complications / diagnosis
  • Postoperative Complications / epidemiology*
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome
  • Univentricular Heart / diagnosis
  • Univentricular Heart / epidemiology
  • Univentricular Heart / surgery
  • Venous Thromboembolism / diagnosis
  • Venous Thromboembolism / epidemiology*
  • Young Adult