Background: 

The most commonly used storage solution for intraoperative short-time storage of harvested saphenous vein grafts is still isotonic saline solution (NaCl). We compared the impact of short-time storage of up to 30 minutes in NaCl with that of a recently developed potassium-chloride and n-acetyhistidine enriched storage solution (TiProtec, Dr. F. Köhler Chemie, Alsbach-Hähnlein, Germany) with special reference to endothelial function.

Materials and Methods: 

Intraoperatively isolated saphenous vein-segments (from pedal) were stored in NaCl or TiProtec for 30 minutes at room temperature (n=14, each group). Subsequently the extracted segments were examined ex vivo in a Mulvany-myograph. Following preconstriction with noradrenaline, concentration-relaxation curves were assessed for bradykinin (10^-9 - 10^-4.5 M) and sodium-nitroprusside (SNP, 10^-9 - 10^-4 M). We assessed the maximum of developed vessel wall tension and subsequently endothelium- and smooth-muscle-cell dependent vasorelaxations.

Results: 

Mean storage time was 27.4±2.4min in both groups. After this storage period, maximum of developed vessel wall tension in response to norepinephrine was significantly better preserved in TiProtec-group (6.29±1.61mN/mm) than in NaCl group (2.31±0.45mN/mm; p=0.032). Endothelium-induced vasorelaxation in response to bradykinin was significantly reduced in NaCl-group; the maximum of relaxation only reached 12.3±2.5% in NaCl-group, but 22.2±3.7% in TiProtec-group (p=0.039). Endothelium independent relaxation, induced by SNP stimulus, was similarly preserved in both groups (NaCl: 86.1±12.9%; TiProtec: 91.1±6.2%, p=n.s.).

Conclusion: 

Even after a short storage periods of less than 30 minutes (relevant for venous bypass grafting), NaCl storage significantly compromises vessel wall tension and endothelium dependent relaxation. TiProtec is able to minimize this loss of function significantly.