Improved Rat Heart Preservation Using High-Pressure Gaseous Perfusion with Oxygen-Xenon Mixture

To address limitations in static cold storage (SCS) of donor hearts, we developed the High-Pressure Gaseous Perfusion without Fluidic Preservation Media (HIPPER) method, along with the necessary equipment for its application.

33 Wistar rat hearts were split into five groups: (Control) static cold storage (SCS) in HTK solution, (Exp) HIPPER using oxygen-xenon gas mixtures of varying ratios ("Gas-A": 1/9, "Gas-B": 9/1, and "Gas-C": 1/1), and (Air) HIPPER using air. Hearts were preserved for six hours, followed by a one-hour Langendorff assessment.

Beating was restored in 4/10 Control hearts, 15/15 Exp hearts across all gas mixtures (p = 0.001 Control vs. Exp), and 6/8 Air hearts. Among resuscitated hearts, the mean heart rates (in bpm) were 131 ± 10 (Control), 164 ± 21 (Air), and 226 ± 13 (Exp) (p = 0.001 Control vs. Exp; p = 0.015 Exp vs. Air). The mean left ventricular pressures (in mmHg) were 31 ± 5 (Control), 45 ± 9 (Air), and 73 ± 7 (Exp) (p = 0.002 Control vs. Exp; p = 0.014 Exp vs. Air), with dP/dT max/min showing consistent trends (p < 0.006 Control vs. Exp and Air vs. Exp). Infarct size in Exp group was also significantly reduced, averaging 39.6 ± 6.6% (Control), 12.6 ± 3.3% (Air), and 6.3 ± 0.7% (Exp) of total myocardium area (p < 0.014 for Control vs. all).

as evidenced by both quantitative and qualitative data, HIPPER consistently outperformed SCS following six hours of storage of rat heart regardless of the gas mixture, highlighting its potential as a more robust preservation method.