Subclinical Leaflet Thrombosis and Anticoagulation After Transcatheter Aortic Valve Replacement

Subclinical leaflet thrombosis affects approximately 15% of patients after transcatheter aortic valve replacement (TAVR). The pathophysiology and clinical significance of leaflet thrombosis remain incompletely understood. Defining the optimal management strategy in patients who are asymptomatic, including the role for oral anticoagulation (OAC), is a key challenge for the field.Three recent randomized trials have evaluated the role of OAC in patients after TAVR. These studies have confirmed prior observational data suggesting that OAC is effective at prevention of subclinical leaflet thrombosis. Overall, however, OAC does not lead to a clinical benefit over the period studied, and in some patients may be harmful owing to bleeding risk.Strategies for identification of patients in whom the benefit of OAC outweighs the risks are required for optimization of long-term outcome after TAVR. This requires clearer insights into the mechanisms of asymptomatic leaflet thrombosis, its clinical significance, and patient-specific risks of bleeding and structural valve degeneration.