Novel Leaflet Biomaterial for Pulmonary Artery Valve

ABSTRACT Trans catheter pulmonary valve implantationTPVIis becoming the treatment of choice in most congenital heart diseaseCHDpatients with degeneration of a previous right ventricular outflow tractRVOTrepairSince the life expectancy of these patients is improvingthere is an increased demand for these proceduresEarly efficacy and safety have been demonstrated for the Medtronic Melody and the Edwards Sapien valvesalthough there are no consistent procedural recommendationsThere are also concerns with regards to the risk of endocarditis in the Melody transcatheter valve implantsRequirements for valve substitutes include features such as a lower introducer profileandltFrlow inflammatory responselong durabilitylow opening resistance with maximal valve areafast and reliable closureand non thrombogenicityFurthermorestructural valve failure is also caused by calcification which is histologically evident withinyears of valve implantationTo address some of these shortcomingswe have identified a new type of heart valve leaflet tissue that promises greater longevity than the conventional glutaraldehyde fixed bovine pericardiumBPThis tissueobtained from porcine pulmonary visceral pleuraPVPis highly elastic and yet thinnerof the thicknessthan BP of similar strengthThe PVP has been tested in venous prosthetic valve applicationbut because of its significant strength and elasticityit has the potential to make TPVI more durableIn this Phase I projectthe objective is to investigate the durability of the PVP tissue in animalsin pulmonary artery environmentIn order to accomplish this goalwe set the following two Specific AimsTo create smaller profileFrtranscatheter pulmonary valve from PVPWe have already developed a percutaneous prosthetic venous valve which will be upscaled to the size of pulmonary artery in sheepSinceof the profile of the transcatheter valve is taken up by the leaflet tissueareduction of thickness of tissue will allow a significant reduction of overall delivery systemTo assess chronic in vivo performance of PVP TPVI into juvenile sheep for up tomonthsThe juvenile sheep model is the recognized gold standard for prosthetic valve testingGood valves last formonths without tears and mineralization while bad valves start to fail withinmonths and show heavy mineral depositsIn this Phase I proof of concept studywe will demonstrate that TPVI valves incorporating PVP will be more resistant to calcification and thus offer better long term durability than the current bioprosthetic valves using BP at smaller delivery system profileIf PVP is truly more tolerant of cyclic stresses and calcifies to a lesser degree as its composition may suggestit would increase the longevity and durability of transcatheter valvesand potentially expand the use of transcatheter valves in younger patients with a greater life expectancyThis would deliver the benefits of transcatheter valves to the bulk of the patient population in need of bioprosthetic valve implants which would substantially impact healthcare and associated costsSpecific to the current applicationthis technology may offer better outcome for CHD patients which are generally underrepresented and understudied NARRATIVE The goal is to develop a new tissue heart valve based on a novel leaflet tissue to prolong the life span and durability of the pulmonary valveThis would reduce reoperations in patients with congenital heart disease and substantially reduce healthcare costs