Glycine application and right heart function in a porcine heart transplantation model

Summary Glycine reduces ischemia‐reperfusion injury after experimental liver transplantation. We hypothesized that glycine might also protect right heart function in an isovolumic cardiac transplantation model. In six domestic donor pigs 150 ml of a 300 mmol l‐glycine solution were administered intravenously. The hearts were then arrested with histidine‐tryptophan‐ketoglutarate solution. Animals without prior glycine infusion served as controls (n = 6). After 4 h of ischemia, hearts were transplanted into recipients. An isovolumic model was used in which the right ventricular (RV) volume was controlled in vivo using an intracavitary high‐compliance balloon. After 1 and 2 h of reperfusion the RV balloon volume was gradually increased and the developed pressures were recorded (Pdeveloped = Psystolic − Pdiastolic). Right ventricular failure was defined as a decrease in developed intracavitary pressure. Glycine hearts could be loaded with a significantly increased volume after 1 h (glycine: 53 ± 13.7 ml vs. control: 32 ± 11.7 ml; P = 0.015) and after 2 h (67 ± 18.6 ml vs. 43 ± 8.2 ml; P = 0.018). Maximal RV developed pressures were not significantly different between groups. Postischemic RV end‐diastolic compliance was significantly higher in glycine‐treated animals (P = 0.04). Glycine protects early postischemic RV compliance, but has no important influence on maximal developed pressures.