Preservation of the myocardium by means of cold physiological solutions, as assessed by ventricular function, histochemistry and birefringence

The efficacy of myocardial preservation by means of cold, oxygenated Hartmann's, Bretschneider's, Eagle's Minimum Electrolyte Medium, and micro- or coarsely filtered Krebs' solution has been compared with that afforded by cold alone and by cross-perfusion from a healthy animal. The experimental preparation was an isolated heart free of inherent deterioration over the experimental period of 3 hr when crossperfused. Assessment was by isovolumic ventricular function tests and histological, histochemical and birefringence examination of drill biopsies. No means of cold, in vitro preservation of the heart permitted it to retain its mechanical performance as well as did normothermic cross-perfusion from a healthy animal, but all cold, oxygenated physiological solutions infused into the coronary arteries performed better than cold alone. Although few statistical differences were shown among the solutions, microfiltered modified Krebs' solution and modified Eagle's Minimum Electrolyte Medium were consistently more effective. Histochemical and birefringence behavior of the myocardium was disappointing in predicting mechanical performance of the myocardium after cold preservation, presumably because cold permits histochemical appearances to be preserved when function is not. Nevertheless, the groups with the poorest residual function showed the most histological damage.