Leaflet immobility and thrombosis in transcatheter aortic valve replacement

Figure 1. Causes of bioprosthetic valve dysfunction. Reproduced with permission.4

Figure 2. Vortices generated within the sinuses of Valsalva using time-resolved three-dimensional magnetic resonance phase contrast imaging. Top row: particle paths at peak systole delineate haemodynamics in the thoracic aorta of 60-year-old patient with sinus prosthesis (A), of a healthy 53-year-old age-matched volunteer (B), and a 30-year-old young volunteer (C). Bottom row: sinus vortices in the right and left coronary sinus as visualized by instantaneous streamlines. Dashed lines demonstrating sinus borders and dotted lines delineating vortex direction. These vortices may play a role in reducing the risk of thrombus formation on the aortic side of the leaflets in native and surgical aortic valve replacements. Vmax, peak velocity. Reproduced with permission.30

Figure 3. Transcatheter aortic valves divide the native aortic sinus of Valsalva into two new spaces: a smaller native sinus between the aortic wall and the native aortic valve leaflet (#) and a new ‘neo-sinus’ bounded by the native aortic valve leaflet and the transcatheter aortic valve leaflet (*) where thrombus is usually observed. TAVR, transcatheter aortic valve replacement.

Figure 4. Contours of blood residence time (TR) in seconds on the aortic valve leaflets and sinuses at the end of diastole. Top panel: comparison between surgical vs. transcatheter aortic valve replacements. Bottom panel: comparison between supra-annular vs. intra-annular valve-in-valve deployment. Modified and reproduced with permission.19 , 32.

Figure 5. Examples of hypoattenuated leaflet thickening in transcatheter aortic valve replacements (top row) and surgical aortic valve replacements (bottom rows). HALT, hypoattenuated leaflet thickening; SAVR, surgical aortic valve replacement; TAVR, transcatheter aortic valve replacement.