Faculty Bibliography

We performed bilateral femoral artery dissections in a single 50 kg mongrel dog. Digital fluoroscopic arteriograms documented the luminal diameter of the left iliac and right superficial femoral arteries. Balloon thrombectomy catheter passage was performed through hemostatic sheaths by 12 surgeons. Embolectomy balloons were filled with radiographic contrast material and the balloon catheter diameter was compared with the underlying vessel diameter. The percentage of overdistention of the embolectomy balloon relative to the arterial wall was 23% +/- 5% in the iliac artery and 40% +/- 13% in the femoral artery. Over a 25-month period, we used fluoroscopically assisted thromboembolectomy to treat 21 patients with acute arterial or graft occlusions. As the balloon was gently withdrawn to extract intravascular thrombus, deformities of the compliant balloon profile caused by underlying arterial lesions were identified fluoroscopically and their locations recorded to facilitate further treatment. After initial clot removal in these 21 patients, 15 residual lesions were documented. Repeat thrombectomy (n = 8), balloon angioplasty (n = 3), and placement of intravascular stents (n = 4) eliminated all 15 lesions. Luminal continuity was successfully restored in all 21 of these patients, 10 of whom required distal open vascular reconstruction to correct existing outflow artery disease. Fluoroscopically assisted thromboembolectomy is a simple and safe method for treating acute arterial or graft occlusions in patients with diffuse arteriosclerosis. It minimizes arterial damage and blood loss during balloon thrombectomy and reduces the need for intravascular contrast agents. It also has the potential to facilitate accurate identification, localization, and treatment of significant underlying arterial lesions

PURPOSE: The expression of c-MYC oncoprotein in proliferating smooth muscle cells (SMCs) was analyzed in an experimental model of vein graft intimal thickening. METHODS: Superficial epigastric vein grafts were inserted into the femoral arteries of male Sprague-Dawley rats. The vein grafts were harvested at 6 hr, 2 days, 1 week, 2 weeks, and 4 weeks after grafting and were rapidly frozen in liquid nitrogen. Immunohistochemical labeling and morphologic analysis of vein graft sections with a double staining technique were used to identify c-MYC/alpha SMC actin and proliferating cell nuclear antigen (PC10)/alpha SMC actin within intimal cells. c-MYC/alpha SMC actin and PC10/alpha SMC actin positive cells were quantitated in the perianastomotic area (R-1) and the body of the graft (R-2) for each time period. Total wall and intimal thickness of perfusion fixed vein grafts were measured with a computer digitized system. RESULTS: Intimal and total wall thickening in the R-1 region peaked at 1 week (27.4 and 579.4 microns respectively) and were significantly thicker (P < 0.01) than the same region at 6 hr after graft implantation (6.0 and 113.5 microns respectively). Staining for c-MYC and PC10 in R-1 was also significantly higher (P < 0.05) at 1 week (5.75 and 7.00 positive cells/10 cells, respectively) compared with that at 6 hr (1.5 and 1.33, respectively). The R-1 region stabilized and remodeled over the following 3 weeks, while c-MYC and PC10 staining progressively decreased. In the R-2 region, intimal thickness significantly increased (P < 0.05) from 6 hr (4.0 micrometers) to 1 week (12.0 micrometers) and stabilized, while total wall thickness increased throughout the first week and the difference became significant at 2 weeks (P < 0.05). Staining for c-MYC and PC10 paralleled the staining in R-1 with a significant peak at 1 week (P < 0.05). CONCLUSIONS: c-MYC oncoprotein is expressed early after experimental vein grafting, with peak expression at 1 week. This occurs during a period of maximal intimal thickening, SMC proliferation, and increased expression of PC10. Expression of c-myc protooncogene may contribute to the induction and regulation of SMC proliferation, producing intimal hyperplasia

PURPOSE: This study was undertaken to evaluate our results of polytetrafluoroethylene (PTFE) tibial and peroneal artery bypasses done for limb salvage. METHODS: Within a group of patients undergoing infrainguinal limb salvage bypasses at our institution between January 1986 and May 1995, 63 patients faced an immediate amputation, had no autologous vein on duplex examination and operative exploration, and had only a tibial or peroneal artery as an outflow vessel for bypass. Most of these patients (82%) had two or more prior ipsilateral infrainguinal bypasses. These 63 patients underwent 66 PTFE bypasses to a tibial or peroneal artery without a distal anastomotic vein cuff or an adjunctive arteriovenous fistula. Our results were then compared with those reported from infrapopliteal (crural) bypasses performed with alternate autologous vein sources or PTFE in conjunction with various recommended adjuncts. RESULTS: The 3- and 5-year cumulative primary graft patency rates for our PTFE infrapopliteal bypasses were 39%+/-7% and 28%+/-9%, respectively. Secondary graft patency rates were 55%+/-8% and 43%+/-10% at 3 and 5 years, respectively. Limb salvage rates were 71%+/-7% at 3 years and 66%+/-8% at 5 years. Two-year actuarial patient survival rate was only 67%+/-7%. CONCLUSIONS: These results indicate that a PTFE bypass to an infrapopliteal artery remains a worthwhile option in patients without usable autologous vein. The secondary patency and limb salvage rates were acceptable in this setting and were not significantly different from the best results reported with prosthetic tibial/peroneal bypasses with distal vein cuffs or patches (74% at 1 year; 58% at 3 years), arteriovenous fistulas (71% at 1 year) or composite arm vein grafts (39% and 29% at 3 and 5 years, respectively)