Papaverine solutions cause loss of viability of endothelial cells

The optimal composition of the solution used for irrigation of saphenous veins used for cardiac surgery may influence ultimate graft patency due to potential injurious effects on the vein endothelium of some of the solution constituents.

The viability of cultured saphenous vein endothelial cells was assessed after incubation of saphenous vein endothelial cells with solutions containing saline, saline with papaverine (0.15 M NaCl, 32.5 mg/mL papaverine), culture medium and buffered saline solution (Plasma-Lyte-A).

Cell viability was significantly decreased after one hour incubation with solutions containing saline with papaverine (24.4+/-9.4%) as compared to culture medium and buffered saline solutions (medium 100%, Plasma-Lyte-A 86.8+/-6.90%). Loss of viability was directly related to the length of exposure of the cultured cells to papaverine. Morphologic changes of cells incubated with saline: papaverine were also seen including cell retraction and nuclear pyknosis. The cells exposed to medium recovered 100% viability whereas by 4 hours only 22% of the saline: papaverine cells were viable, and by 3 days this viability had fallen to 7.7%.

Loss of viability was shown in cultured saphenous vein endothelial cells exposed to saline solutions containing papaverine, whereas no difference was found between culture medium, saline and balanced salt solutions. Cell death was directly related to the length of exposure of the cells to papaverine. Further, after short- and long-term recovery periods, there was little recovery of cell viability. Although papaverine is a potent vasodilator, exposure to this compound may compromise long-term viability of graft endothelial cells.