RESUMEN
Objective • To establish New Zealand rabbit autogenous vein graft model and observe the changes of intimal hyperplasia in vein grafts at different time after grafting. Methods • 35 female New Zealand rabbits of 10 weeks old were randomly divided into 5 groups (7 rats in each group), i.e. postoperative 7 d group, postoperative 14 d group, postoperative 28 d group, postoperative 60 d group and normal control group. An animal model of external jugular vein common carotid artery bypass grafting was established, and the model construction steps were elaborated and optimized. Hematoxylin-eosin (H-E) staining was used to observe the intimal thickness after surgery and immunofluorescence staining was used to observe the expression of α-smooth muscle actin (α-SMA), which was one of the vascular smooth muscle cell (VSMC) differentiation marker protein. The effect of model construction was finally evaluated. Results • In addition to the normal control group, the other 28 New Zealand rabbits were successfully completed the vein graft operation. All the grafted veins kept unblocked except for one graft in postoperative 7 d group developed thrombosis, and the success rate was 96.4% (27/28). H-E staining and immunofluorescence staining showed significant intimal hyperplasia after vein grafting. Compared with the normal control group, the intimal thickness of the vein grafts was significantly increased (all P=0.000) and the fluorescence intensity of α-SMA was significantly enhanced at each time group after surgery. Conclusion • New Zealand rabbit vein graft intimal hyperplasia modeling has an ideal success rate and good repeatability, which provides an ideal experimental model for studying the mechanism and prevention of restenosis after vein grafting.
RESUMEN
PURPOSE: Though it has been well known that the autologous vein graft is conduit of choice for infragenicular leg artery bypass, it is still less clear for above-knee femoro-popliteal artery bypass. We attempted to evaluate the outcomes of reversed saphenous vein graft in comparison with polytetrafluoroethylene (PTFE) graft in above-knee femoro-popliteal bypasses for the patients with chronic arterial occlusive disease. METHOD: In a period of 7 years and 9 months, 108 above-knee femoro-popliteal bypasses were performed in 96 patients (91 male, 5 female, mean age 67.3 years). The indications for bypass operation were short distance claudication in 54 (50%), rest pain in 36 (33%), and toe, foot ulcer or gangrene in 18 (17%) limbs. As bypass conduit, autologous reversed saphenous vein was used in 67 limbs, and PTFE graft in 41 limbs. We compared early (<30 days) postoperative complications, primary patency rates of grafts, and late outcomes of the limbs with proven graft occlusion between 2 patients groups (vein graft group vs. PTFE graft group). Primary cumulative graft patency rate were determined by Kaplan Meier method and compared them with log-rank test. RESULT: Early postoperative complications were not significantly different between two groups. During the follow-up period, 20 (18.5%) grafts were lost to follow-up and 14 patients were dead. Primary cumulative patency rates at 1, 3, 5 years were 97.44 +/- 2.53%, 91.11 +/- 4.94%, and 75.92 +/- 14.46% for vein grafts and 81.76 +/- 7.49%, 36.15 +/- 13.42, and 36.15 +/- 13.42% for PTFE grafts respectively. CONCLUSION: In the patients underwent autologous vein graft for above-knee femoro-popliteal bypass, we experienced significantly better long-term patency, less serious surgical complication and less severe recurrent ischemic symptom after graft occlusion than in patients with PTFE graft.