Abstract Background: Reports conflict on the beneficial effects of several cardioplegic solutions such as University of Wisconsin and St. Thomas’ Hospital solutions. Therefore our objective was to assess the efficacy of several cardioplegic solutions for cardiac preservation by comparing University of Wisconsin modified solution (UW-1 and UW-1 + calcium = UW-2), St. Thomas’ Hospital solution N°1 (STH-1), Celsior solution, and a solution from our laboratory, Lyon preservation solution (LYPS). Methods We randomized male rats ( n = 70) to 7 groups: LYPS, Celsior, STH-1, UW-1, UW-2, normal saline solution, and control. All hearts, except control hearts were preserved by cold storage (8 hours, 4°C) in the various solutions. We used isolated non–working-heart preparations (left ventricular function evaluation, n = 5/group) or biopsy specimens (energetic store evaluation, n = 5/group) to assess quality of heart preservation. Results Hearts stored with the saline solution had a mean left ventricular developed pressure (LVDP) of 3.6 ± 1.3 mm Hg. In contrast, LYPS and Celsior hearts had mean LVDP close to that of the control hearts (97 ± 2.6, 92.1 ± 2.2, and 122 ± 1.9 mm Hg, respectively), whereas STH-1, UW-1, and UW-2 hearts presented an intermediate functional response (48 ± 4, 39.9 ± 4.1, and 69 ± 1.8 mm Hg, respectively). The STH-1 and saline hearts showed increased release of creatine kinase (541.9 ± 168 and 1,080.8 ± 126.2 UI/liter, respectively). The energetic charge (EC = [(0.5 ADP + ATP)/ATP + ADP + AMP]) in Celsior, UW-2, and saline was significantly lower ( p < 0.001) than in the other groups. Conclusion The composition of the preservation solutions had a notable effect on myocardial viability. Our results indicated that LYPS and Celsior solutions had comparable efficacy for left ventricular function. However these solutions may offer better preservation than do UW-1, UW-2, or STH-1 solutions.