Integration of compliance chambers into diaphragm displacement pump to double the pumping flow of pediatric paracorporeal pulsatile ventricular assist device - the paracorporeal berlin heart excor…

Integration of compliance chambers into diaphragm displacement pump to double the pumping flow of pediatric paracorporeal pulsatile ventricular assist device - the paracorporeal berlin heart excor is the only FDA-approved ventricular assist device (VAD) for pediatric patients. This pulsatile diaphragm displacement pump (DDP) is small/light weight to facilitate pediatric patient ambulation. However, excor efficiency is only 50% since IT withdraws and pumps blood at different times (interrupted pulsatile flow). This generates a high peak blood flow rate, which may cause blood damage. A paracorporeal continuous flow pedimag VAD has also been used in smaller children. This centrifugal pump is highly efficient due to the constant flow through the drainage/infusion cannulas, but the pedimag pump head must be attached to a bulky/heavy motor, which hinders ambulation. We previously developed a transapical to aorta (TAA) double lumen cannula (DLC) for a minimally invasive ambulatory lvad, which showed excellent 96 HR performance/hemocompatibility in neonate lambs. Our ultimate goal is to develop an efficient, minimally invasive, paracorporeal lvad system for pediatric patients, which combines the small size/weight (ambulation potential) of current interrupted pulsatile flow pump (e.g excor) and the current high efficiency of a continuous flow pump (e.g pedimag). The enabling technology is a compliant diaphragm displacement pump (cddp), which has compliance chambers integrated into the drainage and infusion outlets to double blood flow. The cddp will be high performing due to: 1) noninterrupted/continuous blood flow; 2) infusion/drainage compliance chambers that decrease cddp afterload/increase cddp preload. The lower peak drainage/infusion flow of the cddp will also reduce blood trauma. Preliminary data showed that adding compliance chambers increased pumping flow from 1.1 to 2.6 l/min and decreased peak flow rate. The phase i sbir objective is to design and fabricate a cddp working prototype with optimal compliance chambers size. This cddp will be tested in lambs with our previously developed TAA DLC. Specific aim 1: to design, fabricate, and bench test a cddp. Compliance chambers will be integrated into the cddp drainage and infusion outlets. The cddp will be made of polycarbonate housing with a polyurethane diaphragm in the middle. A tricuspid valve will connect the cddp housing to the two small silicone compliance chambers. The final prototype will be tested for 1 week in a 37% glycerin mock loop for performance/reliability/durability. Specific aim 2: to test the cddp working prototype in lambs. The cddp will be combined with the TAA DLC to form a less invasive, ambulatory lvad, which will be tested in 10-15 KG lambs (n=9) to evaluate 6 HR performance/reliability and initial biocompatibility. Prototype design/fabrication/bench testing will be done at w-z biotech, and the lamb studies will be done at the university of kentucky. Rather than fine-tuning existing technology, our cddp is a novel invention, which will enable a pulsatile paracorporeal VAD with doubled efficiency. This technology can also be used in adults and may significantly impact cardiogenic shock/bridge to heart transplant management.