Imaging Evaluation for the Detection of Leaflet Thrombosis After Transcatheter Aortic Valve Replacement.

Subclinical leaflet thrombosis has been increasingly recognized as a common imaging finding after surgical or transcatheter aortic valve replacement (TAVR) in recent studies. This finding has raised concerns over TAVR valve durability and debates on optimal postprocedural antithrombotic regime. Hypoattenuated leaflet thickening (HALT) and the associated reduced leaflet motion (RELM) were noted as computed tomography hallmarks of the phenomenon. The coexistence of HALT and significant RELM has been suggested as a threshold for reporting of subclinical leaflet thrombosis. This methodology may contribute to the standardization of reporting for research collaboration, hence the better understanding and management of this common yet largely unknown phenomenon.