News: Study finds identifiable causes for breakthrough stroke in A-Fib despite anticoagulation

Patients with atrial fibrillation (A-Fib) who experienced breakthrough ischemic stroke despite anticoagulation often had identifiable causes and faced increased short-term risks for recurrence and heart attack, a recent study from Journal of Neurology found. The causes are mainly interacting drugs or non-cardioembolic mechanisms.

Researchers analyzed data from the retrospective arm of the ASPERA study to identify causes of ischemic stroke that occurred despite ongoing oral anticoagulation in patients with A-Fib and to assess their impact. Patients took anticoagulant continuously in the prior seven days before ischemic stroke, with a last direct oral anticoagulant dose within 48 hours.

Potential causes of oral anticoagulation failure were categorized as drugs with known interactions, competing non-cardioembolic stroke etiologies, and active cancer.

Overall, the study found that 43.9% of patients had at least one potential cause of anticoagulation failure. Of that group, 28.4% were taking drugs with known interactions, 24.3% had competing non-cardioembolic etiologies, and 4.4% had active cancer. Patients with at least one potential cause had a higher risk for 90-day new ischemic stroke compared with those without a potential cause.

Concomitant interacting drugs were associated with a 3.26-fold increased 90-day risk for myocardial infarction in a weighted analysis and were not associated with a higher risk for recurrent ischemic stroke. All-cause and vascular death rates at 90 days did not differ significantly between patients with and without a potential cause, or between those taking and not taking interacting drugs.

"Our results highlight the need for personalized secondary prevention approaches to patients with breakthrough stroke including statins, antiplatelet treatments, and/or other drugs, as breakthrough stroke might depend in many cases on alternative stroke mechanisms rather than on insufficient anticoagulation," the authors wrote.

Editor’s note: To read the full study, click here. To read additional coverage from Medscape, click here.