Valve thrombosis 3 years after transcatheter aortic valve implantation

Impact of BASILICA on Sinus and Neo-Sinus Hemodynamics after Valve-in-Valve with and without Coronary Flow

BACKGROUND/PURPOSE

This study aims at evaluating the impact of BASILICA on neo-sinus and sinus hemodynamics with and without coronary flow. Leaflet thrombosis after valve-in-valve (ViV) may compromise not only leaflet mobility but also affect valve durability and performance.

METHODS/MATERIALS

In a 23 mm transparent surgical aortic valve model, a 23 mm Edwards SAPIEN 3 and a 26 mm Medtronic Evolut were deployed before and after leaflet laceration, in models with and without coronary flow. Neo-sinus and sinus hemodynamics were evaluated in the aortic position of a pulse duplicator and particle image velocimetry was performed in order to quantify sinus flow hemodynamics along with sinus and neo-sinus washout.

RESULTS

BASILICA-type leaflet laceration procedure led to (a) an increase in the velocities in the sinus and the neo-sinus by 50% for Evolut ViV with and without coronary flow, 70% for non-coronary SAPIEN 3 ViV and 10% for coronary SAPIEN 3 ViV, and (b) an improvement in overall washout up to 2 cycles in the neo-sinus and 0.5 cycles in the sinus.

CONCLUSIONS

A BASILICA-type leaflet laceration approach may improve sinus and neo-sinus hemodynamics through decreasing flow stasis and enabling less confined blood flow. BASILICA confers coronary sinus flow patterns to the non-coronary sinus.

Sinus Hemodynamics Variation with Tilted Transcatheter Aortic Valve Deployments

Leaflet thrombosis is a complication associated with transcatheter aortic valve (TAV) replacement (TAVR) correlated with sinus flow stasis. Sinus hemodynamics are important because they dictate shear stress and washout necessary to avoid stasis on TAV leaflets. Sinus flow is controlled by TAV axial deployment position but little is known regarding TAV axis misalignment effect. This study aims to elucidate TAV angular misalignment with respect to aortic root axis effect on sinus flow stasis potentially leading to leaflet thrombosis. Sinus hemodynamics were assessed in vitro using particle-image velocimetry in three different angular misalignments with respect to aorta axis: untilted, tilted away from the sinus and tilted towards sinus. A 26 mm Edwards SAPIEN3 was implanted in a 3D printed model of an anatomically realistic aortic root. TAV hemodynamics, sinus vortex tracking, leaflet shear stress probability density functions, and sinus blood time to washout were calculated. While pressure gradients differed insignificantly, blood velocity and vorticity decreased significantly in both tilted cases sinuses. Shear stress probability near the leaflet decreases with tilt indicating stasis. TAV tilted away from the sinus is the most unfavorable scenario with poor washout. TAV axial misalignment adds to factors list that could influence leaflet thrombosis risk through modifying sinus hemodynamics and washout.

Management of bioprosthetic cardiac valve thrombosis

Valvular thrombosis is a known complication of bioprosthetic valve replacement that usually occurs within a year of implantation. Four-dimensional computed tomography is quickly becoming the gold standard to directly visualize thrombus. Current guidelines for prophylaxis include aspirin for all bioprosthetic valve replacements, dual antiplatelet therapy for aortic valves, and anticoagulation for mitral valves. However, new trials have suggested single-agent antiplatelet therapy or anticoagulation for treatment of bioprosthetic valve thrombosis. Three cases are presented that illustrate the use of anticoagulants and new techniques for detecting thrombosis on imaging.

Reversible thrombotic mitral valve stenosis after transcatheter mitral valve replacement (TMVR): Is life-long anticoagulation therapy necessary?

We describe a case of reversible thrombotic mitral valve stenosis following a valve-in-ring transcatheter mitral valve replacement. Life-long oral anticoagulation in patients who underwent transcatheter mitral valve replacement might be beneficial.