Comparison of St Thomas solution and modified Collins solution in long-term porcine heart preservation

A comparison between St Thomas No. 1 solution (group 1) and modified Collins solution (group 2) in porcine heart preservation for 5 hours was studied. After a single flush, hearts were stored at 4°C and resuscitated by a heart-lung machine primed with diluted blood. At the end of preservation, hearts in group 1 increased in weight by 8.8±1 .4%. However, weights in group 2 decreased by 1.5 ±0.9%. After reperfusion, group 1 and group 2 gained weight by 15.3 ±1.5% and 18.5±1.6% respectively. Myocardial oxygen consumption in group 1 was higher at 15 min and 60 min of reperfusion. Coronary arterial resistance index was higher in group 2 at 1 min and 15 min of reperfusion. Cardiac maximal stroke work index in group 1 was superior to group 2. After reperfusion, the mitochondria in group 1 demonstrated recovery, and myocytes were intact. In contrast, myocardial contraction bands and myocytolysis were observed in group 2, as well as broken mitochondrial membranes and calcium deposition in mitochondria. St Thomas No. 1 solution was better than modified Collins solution.