Purpose of review: We review the prevalence; natural history; impact of subclinical clinical thrombosis on valve hemodynamics, clinical outcomes, and valve durability; and the role of anticoagulation after transcatheter aortic valve replacement (TAVR).
Recent findings: Subclinical leaflet thrombosis is a dynamic finding present in both transcatheter and surgical bioprosthetic aortic valves. This finding is less prevalent in patients on anticoagulation and resolves following initiation of anticoagulation. Routine anticoagulation after TAVR in high-surgical-risk patients was associated with increased mortality and thromboembolic complications. In the absence of a clinical indication for anticoagulation, there is no reason to initiate anticoagulation after TAVR for the prevention of subclinical leaflet thrombosis. In patients with an established indication for anticoagulation, for instance, atrial fibrillation, clinical or symptomatic valve thrombosis, or a clinical event related to valve thrombosis, anticoagulation should be initiated or continued after TAVR to treat the clinical indication.
Keywords: Anticoagulation; Bioprosthetic valve thrombosis; HALT; Hypoattenuated leaflet thickening; Subclinical leaflet thrombosis; Valve thrombosis.