Discriminating between preservation and reperfusion injury in human cardiac allografts using heart weight and left ventricular mass

Background: Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after heart transplantation. This study was designed to distinguish these forms of injury in human allografts. Methods and Results: In 15 donor hearts preserved in University of Wisconsin solution, heart weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339±24 g (mean±SE) before and 340±24 g after transport (P=NS); however, LVM increased 14 g, from 164±8 to 178±11 g (P<.05, paired t test). LVM increased in 10 of 18 patients (56%). No correlation was demonstrated between duration of ischemia (mean, 172±13 minutes) and changes in HW or LVM. Two patients died as a result of primary graft failure. In the first, HW increased 54 g, 2 SD above the mean. In the second, LVM increased 66 g, 2 SD above the mean, but HW changed minimally. Conclusions: While current preservation methods result in minimal change in HW during transport, reperfusion injury frequently increases LVM. LVM determination by two-dimensional echocardiography may prove valuable in detecting allograft injury.