P85: Development Of The University of Pittsburgh Ex-vivo Cardiac Perfusion System: System Minimization Update

Abstract

Background: Heart transplantation remains the definitive treatment for end-stage heart failure; however, the waitlist exceeds the donor organs available. It is difficult to obtain an assessment of organ viability for transplant in many circumstances. We have developed a system that can allow for assessment of organ viability and potentially expand the donor pool. The device will allow for ex vivo assessment of the heart both via Langendorff and physiologic perfusion modes. Initial experiments have been performed on the system with mixed success. This is in part due to the system design and components. The current focus is developing an updated prototype to mitigate some of these problems. Methods: A brief series of perfusion experiments were performed. Hearts were purchased donated by a local slaughterhouse and purchased from Animal Technologies (Tyler, TX) and were used for both recovery and static perfusion experiments to enhance system design. The hearts were connected to the circuit which consisted of an integrated perfusion chamber/reservoir, a PediMag (Abbott) pump, and a Eurosets (Abbott) oxygenator. Whole blood from the donor animal was the perfusate with physiological correction guided by blood chemistries. A sweep gas control unit was utilized to manage perfusate pH and PCO2 during organ perfusion. Slaughterhouse procured hearts were cannulated and rewarmed slowly to test the protocol. Results: Based on initial experiments, we chose to modify our existing design to minimize the overall footprint of our perfusion system. A new organ chamber has been designed with a scalloped heart platform (Figure 1). Circulatory support components will be housed in the rear of the organ chamber. Additionally, we have determined that a pediatric sized oxygenator will meet the VO2 requirements of the perfused organ, which also allows us to investigate the use of an integrated pump/oxygenator as a further system minimization.