Functional and histologic changes in vein grafts exposed to crystalloid potassium cardioplegic solution

A canine external jugular vein to iliac artery interposition model was devised to evaluate the potential deleterious effects of cold potassium cardioplegic solution exposure to saphenous vein grafts during aortocoronary bypass procedures. The right jugular vein was harvested from 11 animals and halved, one segment being perfused with 1 liter of normal saline solution (NS) at 4 degrees C over a period of 31.7 +/- 2.5 min at a perfusion pressure of 50.5 +/- 2.6 mm Hg, and the other segment perfused with 1 liter of crystalloid potassium cardioplegic solution (CP) at 4 degrees C over a period of 24.8 +/- 3.2 min at a perfusion pressure of 53.0 +/- 1.5 mm Hg. The measured differences in the perfusion times and pressures were not significant at P less than 0.05. The grafts were then interposed into the iliac artery systems of their respective animals, and transgraft pressure gradients were measured by direct needle puncture technique and found to be 12.6 +/- 5.9 mm Hg for the CP-treated grafts and 19.9 +/- 9.6 mm Hg for the NS-treated grafts. At the time of graft harvest 7.4 +/- 0.23 months later transgraft pressure gradients were again measured and found to be 2.5 +/- 1.8 mm Hg for the CP-treated and 2.9 +/- 1.7 mm Hg for the NS-treated grafts.(ABSTRACT TRUNCATED AT 250 WORDS)