Optimal temperature conditions for prolonged transport of donor hearts: an experimental study

Objective : to compare the effectiveness of extended heart preservation (up to 6 hours) at a temperature of +4 to +8 °C with the standard method. Materials and methods . The study was conducted using male Landrace pigs weighing 40–60 kg (n = 6). The experimental group (n = 3) underwent heart preservation at an optimized temperature of +4 to +8 °C for 6 hours prior to transplantation. In the control group (n = 3), hearts were preserved using the standard method for the same duration. Following preservation, coronary perfusion was restored ex vivo , cardiac activity was reinitiated, and myocardial function was evaluated alongside biochemical markers of cardiac tissue injury. Results . Following the resumption of blood supply and cardiac activity, both groups showed a reduction in superoxide dismutase (SOD) and malondialdehyde (MDA) levels. In the experimental group (preserved at +4–8 °C), SOD and MDA levels decreased from 12.31 to 8.85 ng/mL per 1 g of protein, while in the control group (standard method), levels declined from 12.04 to 9.23 ng/mL per 1 g of protein. In the experimental group, the level of heart-type fatty acid-binding protein (H-FABP) remained stable, whereas in the control group, it declined from 1.42 to 1.06 ng/mL per 1 g of protein. After prolonged preservation, receptor-interacting protein (RIP) kinase concentrations increased more markedly in the control group (from 0.071 to 0.086 ng/mL) than in the experimental group (from 0.024 to 0.028 ng/mL per 1 g of protein). Additionally, caspase-8 levels in the experimental group significantly decreased from 0.04 to 0.013 ng/mL per 1 g of protein. No significant differences were observed in von Willebrand factor levels between the two groups. However, histological analysis in the control group revealed muscle fiber fragmentation and widespread coagulopathy in myocardial tissue following standard cold («ice») preservation. Conclusion . This pilot experimental study indicates that long-term preservation of donor hearts at a controlled temperature of +4–8 °C is both effective and safe when compared to the conventional preservation method.