Mitral Regurgitation (MR) is a large clinical problem in both children and adults that occurs when the mitral valve fails to close properly and blood flows back through the valve into the atrium. Mitral regurgitation in children is most commonly caused by congenital malformations of the mitral valve, or it develops after surgical repair of a complete atrioventricular canal defect or atrioventricular septal defect. Volume overload on the ventricle due to mitral regurgitation induces rapid deceleration of cardiac function, permanent structural changes in the myocardium and cardiac extracellular matrix, and ultimately irreversible heart failure. Drug therapies to manage patients with MR have had some success in adults, but their outcomes in children remain dismal. A recently abandoned pediatric heart network trial in children investigated the use of ACE inhibitors in children, with poor outcomes. Replacement of the mitral valve with a bioprosthetic valve is a viable option, however it is performed on cardiopulmonary bypass and thus is associated with significant risk of morbidity and mortality.
The MitraCath system for sutureless or transcatheter placement of an artificial mitral valve into the native valve, is a novel technology that eliminates mitral regurgitation without the need for risky open-heart surgery. This technology is based on the use of a nesting design between two opposing self-expanding stents. The outer stent is used for anchoring the stent to the native mitral annulus and creating a circular lumen. The inner stent is used to house the bioprosthetic heart valve and anchor it to the outer anchoring stent. As cardiac catheterization techniques continue to become accessible to the pediatric population, this technology could have significant impact in treating mitral regurgitation and potentially tricuspid regurgitation as well.
APDC is providing funding to develop collapsible prototypes, demonstrate efficacy in ex-vivo bench top testing, and to demonstrate proof-of principle data that the valve is implantable and can take over the function of the diseased mitral valve in animal testing.