PBSH: A New Improved Cardiac Preservation Solution in Comparison With Three Clinically Proven Solutions

Introduction. A solution under development at our institute, based on phosphate-buffered sucrose, has shown good preservation for kidneys and livers. This work used a refined version of this solution (PBSH-phosphate-buffered sucrose for the heart) in heart preservation, comparing it to solutions already widely used (University of Wisconsin, St. Thomas's, and Celsior solutions). Methods. Following an initial washout phase and control working mode on a Langendorff system, hearts were flushed with preservation solution and after 6 hours at 4 degrees C were then reperfused for 15 minutes followed by working heart mode for a further 30 minutes. Hemodynamic parameters were measured and compared with their preischemic values and expressed as percentage recovery. Enzyme measurement came from the collection of the initial 1.5 mL of the coronary effluent after the storage period. This was to test for creatine phosphokinase (CPK) and lactate dehydrogenase (LDH). Hearts were then placed immediately into liquid nitrogen for adenosine triphosphate (ATP), lactate, and creatine phosphate (CP) testing. Spectrophotometric analysis was used to assess both the release of CPK and LDH into the coronary effluent, and the level of ATP, lactate, and CP in the frozen heart tissue. Results. These results show that hearts that are preserved in PBSH are hemodynamically as well preserved as the hearts preserved in other solutions tested and their enzyme and lactate content is lower while having higher levels of energy compounds in these hearts. Conclusion. Overall these results show that PBSH is at least as effective in cardiac preservation in the rat model of 6 hours of cold ischemia as these other widely used solutions tested.