Valved bovine jugular vein (Contegra) conduit is considered a suitable choice for pediatric population with congenital heart defect requiring right ventricle to main pulmonary artery connection. Intermediate follow-up studies have shown the propensity of developing distal conduit stenosis and valve thrombosis. We present a rare case of aneurysmal dilatation of the conduit leading to valve failure requiring conduit explantation.
Contemporary experience with mitral valve (MV) repair in the rheumatic population is limited. We aimed to examine the long-term outcomes of rheumatic MV repair, to identify the predictors of durability and to compare the repair for rheumatic and degenerative MVs.
Platelet activation induced by shear stresses and non-physiological flow field generated by bileaflet mechanical heart valves (BMHVs) leads to thromboembolism, which can cause fatal consequences. One of the causes of platelet activation could be intermittent regurgitation, which arises due to asynchronous movement and rebound of BMHV leaflets during the valve closing phase. In this numerical study, the effect of intermittent regurgitation on the platelet activation potential of BMHVs was quantified by modeling a BMHV in the straight and anatomic aorta at implantation tilt angles 0°, 5°, 10°, and 20°. A fully implicit Arbitrary Lagrangian-Eulerian-based Fluid-Structure Interaction formulation was adopted with blood modeled as a multiphase, non-Newtonian fluid. Results showed that the intermittent regurgitation and consequently the platelet activation level increases with the increasing implantation tilt of BMHV. For the straight aorta, the leaflet of the 20° tilted BMHV underwent a rebound of approximately 20° after initially closing, whereas the leaflet of the 10°, 5°, and 0° tilted BMHVs underwent a rebound of 8.5°, 3°, and 0°, respectively. For the anatomic aorta, the leaflet of the 20° tilted BMHV underwent a rebound of approximately 24° after initially closing, whereas the leaflet of the 10°, 5°, and 0° tilted BMHVs underwent a rebound of 14°, 10°, and 7°, respectively. For all the implantation orientations of BMHVs, intermittent regurgitation and platelet activation were always higher in the anatomic aorta than in the straight aorta. The study concludes that the pivot axis of BMHV must be implanted parallel to the aortic root's curvature to minimize intermittent regurgitation and platelet activation.