Akademik Veri Yönetim Sistemi
JOURNAL OF CARDIAC SURGERY, cilt.2025, sa.1, 2025 (SCI-Expanded, Scopus)
Background: The extracardiac Fontan procedure, a palliative intervention for single-ventricle physiology, is associated with significant thromboembolism and bleeding risks. Warfarin has been the standard anticoagulant, but its limitations have prompted exploration of nonvitamin K oral anticoagulants, such as rivaroxaban. Objective: To compare the safety and efficacy of rivaroxaban vs. warfarin as postoperative anticoagulation in pediatric patients following the extracardiac Fontan procedure, focusing on thromboembolic events, bleeding complications, and treatment adherence. Methods: This retrospective cohort study included 369 pediatric patients (aged 3-17 years) who underwent the extracardiac Fontan procedure at a single center from 2015 to 2022, selected from 412 cases reviewed, with 43 excluded due to incomplete follow-up or comorbidities. Patients received either warfarin (n = 177) or rivaroxaban (n = 192) for anticoagulation. Baseline characteristics, including age, sex, body weight, and pulmonary artery pressure, were comparable between groups. Anticoagulation was initiated on postoperative Day 1 per institutional protocol, excluding aspirin to standardize thromboembolism prevention due to high risk in nonanticoagulated patients. Warfarin was titrated to an international normalized ratio (INR) of 2.0-3.0, while rivaroxaban was dosed per European Medicines Agency guidelines. Outcomes included thromboembolic events (graft thrombosis, pulmonary embolism, and transient ischemic attacks [TIAs]), major and minor bleeding, mortality, and treatment discontinuation over a mean follow-up of 5 years. TIAs were defined per American Heart Association guidelines as transient neurological dysfunction lasting less than 24 h without infarction on neuroimaging. Statistical analyses used Fisher's exact test, Kaplan-Meier survival analysis, and multivariable logistic regression, with p < 0.05 indicating significance; the study was designed to detect a 3% difference in major bleeding. The limited number of thromboembolic events resulted in wide confidence intervals, limiting precision in between-group comparisons. Results: Thromboembolic events occurred in 5.1% (n = 9) of warfarin patients and 2.1% (n = 4) of rivaroxaban patients (OR = 2.5, 95% CI: 0.8-8.2). Major bleeding was significantly higher with warfarin (3.4%, n = 6; 4 intracranial and 2 gastrointestinal) than rivaroxaban (0.5%, n = 1; gastrointestinal; OR = 7.0, 95% CI: 1.2-40.8). Minor bleeding rates were 9.0% (warfarin) vs. 5.7% (rivaroxaban). Two warfarin-related deaths (intracranial hemorrhage and systemic embolism post-TIA) were recorded; none occurred with rivaroxaban. Treatment discontinuation was higher with warfarin (5.1% vs. 0.5%). Conclusions: Rivaroxaban demonstrated a superior safety profile compared to warfarin, with significantly lower major bleeding rates, no associated mortality, and improved treatment adherence in pediatric Fontan patients. Its fixed-dose regimen simplifies management, although implementation requires consideration of cost and formulation access. Risk-stratified approaches and larger prospective trials are needed to optimize anticoagulation strategies.