In Vivo Comparative Study of Two Lactobionate Based Solutions for Prolonged Heart Preservation

Abstract

The duration of safe heart preservation must be improved. Using a heterotopic heart transplantation model, we compared in vivo the recovery of rabbits hearts preserved with a K⁺ Lactobionate based fluid (UW: University of Wisconsin solution) or with a Na⁺Lactobionate based fluid. In the “preservation” group, hearts were cold stored (4°C) for 6 hours with UW (n=9) or Na⁺Lactobionate solution (n=9). In the “transplantation” group, cold storage was followed by 3 hours of reperfusion (UW: n=8, Na⁺Lactobionate solution: n=7). Functional recovery, adenine nucleotide pool, circulating blood cardiac enzymes, circulating blood and tissue malondialdehyde (MDA) were measured. Left ventricular enddiastolic and developed pressures at different preload levels were better after preservation with UW than with Na+Lactobionate solution (p<0.05). Also with UW, adenosine diphosphate and total adenine nucleotide content were significantly higher than with Na⁺Lactobionate solution (p<0.05) whereas adenosine triphosphate, monophosphate and energy charges were similar. Cardiac enzymes and tissue MDA were similar with UW and Na⁺Lactobionate solution. In circulating blood, MDA was not detected. These results enhance the superiority of UW solution over a Na⁺Lactobionate based solution for long term heart preservation.