Severance Hospital study finds anticoagulants reduce stroke risk in atrial fibrillation patients

A research team led by professors Jeong Bo-young, Yoo Hee-tae, and Kim Dae-hoon at Severance Cardiovascular Hospital has demonstrated that anticoagulant therapy significantly reduces complications in atrial fibrillation patients with intermediate stroke risk.

The study, involving 1,803 patients across 18 medical institutions in South Korea, was published in the New England Journal of Medicine and presented at the 2026 European Society of Cardiology and World Heart Federation Annual Scientific Session in Munich.

Results from the 24-month randomized clinical trial showed that patients receiving anticoagulants had a 69% lower cumulative risk of major clinical events compared to the untreated group. Notably, the risk of ischemic stroke or systemic embolism was 90% lower in the treatment group. The study also found that the rate of major bleeding was similar between both groups, suggesting that anticoagulants can prevent complications without significantly increasing bleeding risks for this specific patient demographic.