Aspirin, warfarin, NOACs prevent thromboembolic events in patients with Fontan circulation

Treatment with aspirin, warfarin, and nonvitamin K oral anticoagulant (NOAC) results in a reduced risk of thromboembolic events, suggests a recent study.

A network meta-analysis was conducted to compare the efficacy and safety of aspirin, warfarin, and NOACs in patients with a Fontan circulation. Twenty-one studies (26,546 patient-years) published by February 2022 met the eligibility criteria.

Thromboembolic events were the primary efficacy outcome, and major bleeding was the secondary safety outcome. The authors performed frequentists network meta-analyses to estimate the incidence rate ratios (IRRs) of both outcomes. They also ranked treatments based on probability (P) score.

Use of NOAC (IRR, 0.11, 95 percent confidence interval [CI], 0.03‒0.40), warfarin (IRR, 0.23, 95 percent CI, 0.14‒0.37), and aspirin (IRR, 0.24, 95 percent CI, 0.15‒0.39) each resulted in significantly lower rates of thromboembolic events when compared with no thromboprophylaxis.

However, no significant differences were observed in the rates of major bleeding (NOAC: IRR, 1.45, 95 percent CI, 0.28‒7.43; warfarin: IRR, 1.38, 95 percent CI, 0.41‒4.69; aspirin: IRR, 0.72, 95 percent CI, 0.20‒2.58).

Rankings of treatment revealed that NOACs had the highest P score to prevent thromboembolic events (p=0.921), followed by warfarin (p=0.582), aspirin (p=0.498), and no thromboprophylaxis (p=0.001). Notably, aspirin appeared to have the most favourable overall profile.

“Recognizing the limited number of patients and heterogeneity of studies using NOACs, the results support the safety and efficacy of NOACs in patients with a Fontan circulation,” the authors said.