Risk for Thromboembolic Events Might Not Be Higher After Cardioversion

These investigators considered whether cardioversion causes thromboembolic events or is a risk marker of patients' vulnerability; in a causal relationship, the risk should be elevated after cardioversion but not beforehand. They analyzed data from the manufacturer-funded ACTIVE thrombosis prevention trials, focusing on the 962 enrollees with atrial fibrillation (mean age, 66; 58% men) who had been randomized to single or dual antiplatelet therapy (but not oral anticoagulation) and who underwent cardioversion during the studies.

The median CHA₂DS₂-VASc score was 3. The median time from randomization to first cardioversion was 222 days; the median follow-up afterwards was 379 days. Electrical and pharmacological cardioversions were performed o…