Comparison of Two Graft Storage Solutions (DuraGraft and TiProtec) in an In Vitro Model of Ischemia-Reperfusion Using Arterial Grafts

Objectives: Endothelial damage is believed to be one of the main reasons for graft failure in coronary artery bypass graft (CABG) surgery. However, storage protocols in CABG surgery are rather simple, with grafts being stored in saline, blood-based solutions or Custodiol. In this study, we examined the effect of the two currently available storage solutions DuraGraft and TiProtec on the endothelial function of an arterial graft in an in vitro ischemia-reperfusion model.

Methods: Thoracic aortae from rats (Sprague Dawley, male, n = 4 per group) were isolated and underwent 24-hour cold ischemic preservation in saline, DuraGraft or TiProtec storage solution. Reperfusion injury was simulated by hypochlorite (200 μmol) exposure for 30 minutes. Endothelium-dependent vasorelaxation to acetylcholine (ACh) and endothelium-independent vasorelaxation to sodium nitroprusside (SNP) were assessed in an organ bath. Results were compared with controls, which did not undergo ischemia and reperfusion injury.

Results: Aortic segments preserved in DuraGraft or TiProtec showed significantly attenuated endothelium-dependent maximal relaxation (Rmax) to acetylcholine (ACh) after in-vitro induced ischemia-reperfusion injury (Rmax control: 98 ± 1%; saline: 41 ± 6%; DuraGraft: 86 ± 3%; TiProtec: 92 ± 2%, < p < 0.05). Endothelium-independent vasodilative response to sodium nitroprusside (SNP) was similar in both groups.

Conclusion: We demonstrated that DuraGraft and TiProtec storage solutions both effectively preserve endothelial function of an arterial graft after ischemia-reperfusion injury. This might be an option to reduce graft failure and even improve long-term patency.