Alternative autogenous vein grafts to the inadequate saphenous vein

Autogenous veins other than single-length greater saphenous vein were used in 150 operations to revascularize the extremities of 138 patients; three operations were for upper extremity ischemia and four were lower extremity reconstructions with lesser saphenous vein grafts. The remaining 143 bypasses were performed to revascularize lower extremities in 131 patients. Arm vein grafts were used in 102 operations, and 14 different combinations of vein segments were used to construct 41 totally autogenous composite vein grafts. Tissue necrosis or rest pain was the indication for 70% of arm vein bypasses; 52% of these grafts extended to an infrapopliteal artery. The 1-, 3-, and 5-year patency rates were 82%, 69%, and 60%, resulting in limb salvage rates of 93%, 91%, and 81%, respectively. Composite autogenous vein grafts resulted in a 1-year limb salvage rate of 79% in a select group of elderly patients with advanced arterial disease, poor runoff, and profound ischemia. Limb salvage was the indication for 93% of these operations; tissue necrosis was present in 71% while 80% required infrapopliteal reconstructions--37% to a peroneal artery and 29% to the ankle or foot. Successful limb salvage has been accomplished with alternative autogenous veins when the greater saphenous vein is missing or inadequate, dramatically reducing the use of prosthetic conduits in our practice.     

Cod-liver oil in the prevention of intimal hyperplasia in autogenous vein grafts used for arterial bypass

Cod-liver oil, rich in eicosapentaenoic acid, an unsaturated fatty acid, was administered to 14 mongrel dogs to determine if this acid would prevent platelet-mediated intimal hyperplasia. Twenty-eight 1 cm segments of undistended jugular vein were interposed between bilaterally divided femoral arteries. Seven control animals were fed a 2% cholesterol diet 1 week before and for 6 weeks after the operation. A further seven animals received cod-liver oil capsules containing 1.8 gm of eicosapentaenoic acid daily 1 week before and for 6 weeks after autogenous vein implantation, in addition to the lipid-supplemented diet. Baseline serum cholesterol was 4.6 +/- 0.4 mmol/L. The rise in serum cholesterol was similar in the two groups and increased to 7.4 +/- 0.6 mmol/L (control group) and to 6.8 +/- 0.2 mmol/L (eicosapentaenoic acid group) (p less than 0.001). Prothrombin time, partial thromboplastin time, bleeding time, and platelet counts were unchanged in the two groups. Vein grafts, harvested at 6 weeks, were fixed in formaldehyde. Mean intimal thickness was measured from multiple vein graft cross sections with a Zeiss computerized interactive image analyzing system. A mean of 140 +/- 11 measurements were computed from each graft. Marked intimal hyperplasia occurred in the control group and increased from 4.3 +/- 0.3 to 86.4 +/- 14 micron. In contrast, a high eicosapentaenoic acid diet inhibited intimal hyperplasia, with intimal thickness only increasing from 4.0 +/- 0.4 to 24.8 +/- 2.7 micron (p less than 0.001). These data indicate that eicosapentaenoic acid inhibits platelet-mediated intimal hyperplasia and suggest that cod-liver oil could be used to prevent intimal hyperplasia in vein grafts used for myocardial revascularization.     

Cryopreserved saphenous vein allografts in infrainguinal arterial reconstruction

Cryopreserved saphenous vein allografts (cryografts) have been used as conduit in infrainguinal revascularization when autogenous vein is inadequate or unavailable. Numerous reports on the subject exist, however most are hampered by small sample size or retrospective design. Despite poor patency rates, limb salvage in patients undergoing cryograft bypass is acceptable. In this article we review the literature of cryograft use in infrainguinal revascularization and define its role in the armamentarium of the modern vascular surgeon.     

Should polytetrafluoroethylene grafts be used in preference to saphenous vein for femoropopliteal arterial bypass?

Some surgeons have advocated using polytetrafluoroethylene (PTFE) as the graft material of choice for femoropopliteal arterial bypass so that the saphenous vein could be preserved for future cardiovascular surgery. We have examined our results to see if this approach could be justified in our patient population. PTFE was used for 101 femoropopliteal reconstructions in 96 patients (56 male and 40 female). Thirty-eight (40%) complained of debilitating claudication and 58 (60%) had limb-threatening ischaemia. There were 83 primary PTFE femoropopliteal reconstructions and 18 repetitive procedures after failure of an earlier ipsilateral bypass. Twenty-nine of the 101 PTFE grafts were anastomosed distally to the popliteal artery above knee and the remaining 72 below knee. At 5 years, the cumulative patency for all grafts was only 11%. The 4 year cumulative patency was better for claudicants (40%) than for those with threatened limb loss (11%) but two of the 38 claudicants required amputation when their grafts failed. Patency rates were not significantly affected by the site of the distal anastomosis or by a previous failed ipsilateral femoropopliteal bypass. Worthwhile limb salvage was achieved only by frequent re-operation. Our results with PTFE are not good enough to use it in preference to an adequate saphenous vein for femoropopliteal bypass.     

Randomization of autogenous vein and polytetrafluorethylene grafts in femoral-distal reconstruction

A randomized, prospective, controlled study comparing autogenous saphenous vein and polytetrafluoroethylene (PTFE) grafts in infrainguinal arterial reconstructions has been initiated in three different institutions. A total of 446 operative procedures were divided into six groups, depending on the site of distal bypass insertion into the popliteal or an infrapopliteal artery and on whether the patient received a randomized vein or PTFE graft or an obligatory PTFE graft. The randomized saphenous vein graft patency to infrapopliteal arteries was significantly better (P less than 0.005) at 2 1/2 years than the patency of randomized or obligatory PTFE grafts to the same level. No significant differences between randomized vein grafts and randomized or obligatory PTFE grafts in the femoropopliteal position could be demonstrated up to 2 1/2 years, either above or below the knee. The need for such a study and the limitations of this preliminary report are discussed. The requirement for longer observation of greater numbers of cases is stressed. A current plan for usage of the PTFE graft in the lower extremity is presented.     

Correlation between preoperative and postoperative duplex vein measurements of the greater saphenous vein used for infrainguinal arterial reconstruction

Vein diameter measurements using B-mode Doppler ultrasound (US) are used to assess the greater saphenous vein (GSV) for bypass operations; a 2.5-3.0 mm diameter is suggested as a minimum. Preoperative measurements are made while the vein is in the low-pressure venous system. This may not reflect the distended diameter of a vein after placement in the arterial system. This study compares preoperative and postoperative GSV diameters to identify the degree of dilatation and the minimal size adequate for use in arterial bypass operations. The GSV of 11 patients undergoing an infrainguinal arterial bypass were assessed by utilizing Doppler US. Measurements were taken every 10 cm, for 70 cm, along the course of the GSV before and 4 weeks after operation. All segments showed a percent increase in diameter from the preoperative to postoperative time points; 10 cm, 38+/-; 20 cm, 31+/-; 30 cm, 16+/-; 40 cm, 26+/-; 50 cm, 23+/-; 60 cm, 28+/-; and 70 cm, 22+/-. A Bonferroni post hoc analysis between the 2 time point means showed a significant increase in means for the 2 time points of 9.49 units (Bonf p value < 0.001). Preoperative vein segments were divided into 3 categories: 4.1 mm. All showed a significant increase over time. Preoperative diameter measurements of the vein may not reflect the final distended diameter after bypass. Preoperative vein diameters 相似文献   

Infrainguinal arterial reconstruction with nonreversed greater saphenous vein

Purpose: This study was undertaken to examine the effectiveness and the possible advantages of infrainguinal arterial reconstruction with nonreversed greater saphenous vein (NRGSV) grafts. We reviewed the results achieved with 189 consecutive NRGSV bypass procedures from July 1, 1985, to August 31, 1995, and compared them with 568 consecutive in situ greater saphenous vein (INGSV) bypass procedures completed over the same interval.Methods: NRGSV bypass procedures were performed by selecting the optimum inflow and outflow vessels and then excising the best available appropriate-length segment of greater saphenous vein. The valves were lysed with a Mills valvulotome using gentle antegrade distention with an isotonic electrolyte solution containing heparin (1000 U/500 ml) and papaverine (60 mg/500 ml). The graft was then translocated to the inflow site, where the proximal and distal anastomoses were sequentially completed, followed by a completion arteriography.Results: Demographic and risk factor characteristics did not differ between patients who underwent NRGSV and those who underwent INGSV bypass. Compared with INGSV bypasses, NRGSV bypasses were more commonly secondary procedures (26% vs 8%; p < 0.001) and were more often performed for limb salvage indications (89% vs 68%; p < 0.001). NRGSV bypasses also had more distal inflow vessels (23% superficial femoral artery [SFA] and 28% popliteal artery [POP] vs 10% SFA and 1% POP; p < 0.001) and more distal outflow vessels (52% tibial and 22% pedal artery vs 47% tibial and 3% pedal artery; p < 0.001) than did INGSV bypasses. Despite the higher incidence of secondary bypass procedures and more distal outflow vessels in the NRGSV group, the overall results achieved at 5 years did not differ between the two groups. The 5-year primary patency rates were 65% ± 5% for NRGSV and 72% ± 3% for INGSV ( p < 0.12), and the 5-year secondary patency rates were 74% ± 5% and 82% ± 2% ( p < 0.08), respectively. Similarly, the 5-year limb salvage rate among bypass procedures performed for limb salvage indications did not differ for NRGSV (82% ± 5%) and INGSV (90% ± 2%; p < 0.06).Conclusions: The application of the NRGSV bypass graft preserves the INGSV's main advantage of optimal size match between artery and vein at each anastomosis, but facilitates the tailoring of the procedure to the patients anatomy and the completion of the bypass with the shortest, best-quality conduit available. Our application of the NRGSV in a more challenging series of bypass procedures produced equivalent results to those achieved in a concurrent series of INGSV bypass procedures. (J Vasc Surg 1996;24;957-62.)     

Flow waveform analysis and long-term results of autogenous saphenous vein and polytetrafluoroethylene grafts in 140 arterial reconstructions of the lower limbs

In previous work we have found that the outcome of grafts in the lower limbs correlated with the flow waveform pattern of the artery. We have retrospectively reviewed 140 femoro-popliteal bypass operations involving the use of 75 saphenous vein grafts and 65 polytetrafluoroethylene (PTFE) grafts. For grafts with type 0 or I flow waveform pattern the patency at 4 years (56%) was superior to grafts with the type II, III or IV flow waveform (35%) patterns (P less than 0.05). For saphenous vein grafts with type 0 or I flow, the patency rate was 78% at 3 years and 69% at 5 and 8 years. In contrast with type II, III or IV flow the patency rate was 52% at 3 years, 48% at 5 years and 34% at 8 years, with a statistical significance at 4 years (P less than 0.05). PTFE grafts with type 0 or I flow showed a tendency toward an increased patency which was not significant in comparison with the grafts with type II, III or IV flow (P = 0.12). Saphenous vein grafts with type II flow patterns had an increased occlusive rate in the first year whereas PTFE grafts had the same tendency within 2 years. In both types of graft, early occlusions within a month of operation were encountered in grafts with a type III or IV flow waveform pattern. These results indicate that the fate of the reconstructed arteries of the lower limb could be predicted by flow waveform analysis, and a careful and serial postoperative evaluation of the graft should be made, particularly those with type II, III or IV flow waveform patterns.     

Cryopreservation affects endothelial and smooth muscle function of canine autogenous saphenous vein grafts

Cryopreserved veins used as arterial grafts may be affected by both rejection and the cryopreservation process. Experiments were designed to study changes in endothelial and smooth muscle function after cryopreservation but independent of rejection. One saphenous vein from each of eight dogs was cryopreserved for subsequent use as autografts. After 3 weeks one cryopreserved and one freshly harvested autogenous saphenous vein were implanted as bilateral femoral arterial interposition grafts. Platelet deposition was studied in vivo with indium 111-labeled platelets. At 4 weeks the autografts were removed, and the functional characteristics of the grafts were studied in organ chambers; and the ability of nerve terminals to uptake transmitter was studied with 3H-norepinephrine. Neither patency rates, blood flows, nor platelet deposition were significantly different between freshly harvested and cryopreserved grafts. Uptake of 3H-norepinephrine was significantly reduced in both grafts as compared to unoperated veins. The smooth muscle of the cryopreserved and fresh grafts contracted comparably to alpha-adrenergic agonists and endothelin. In cryopreserved grafts, the maximal tensions that developed to KCl, prostaglandin F2 alpha, and endothelin were greater when the endothelium was present compared to that developed by the smooth muscle alone. Calcium ionophore A23187 caused relaxations only in rings with endothelium; these were not significantly different between graft types. However, relaxations of the smooth muscle to nitric oxide were decreased in the cryopreserved grafts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Polytetrafluoroethylene versus autogenous vein grafts for vascular reconstruction in contaminated wounds

A high incidence of dissolution and disruption of infected autogenous vein grafts has been demonstrated. PTFE, on the other hand, has been shown to maintain its structural integrity in the presence of well-entrenched infection, with a relatively small incidence of anastomotic disruption related to host artery necrosis. In addition, PTFE performed as well as autogenous vein when antibiotics were administered. Therefore, PTFE graft material is advocated for controlled clinical trials in patients with contaminated vascular injuries.     

Long term results of autogenous vein bypass grafts in femoropopliteal arterial occlusion

The results of 329 consecutive autogenous vein grafts carried out between January 1962 and June 1973 have been reviewed. The 5- and 10-year mortality rates were 14.6 per cent and 18.7 per cent respectively. The corresponding patency rates were 70 per cent at 5 years and 34 per cent at 10 years, the lowest patency (27.8 per cent) occurring in below-knee anastomoses with grafts of 5 mm or less in diameter. As other have noted, the state of the popliteal--tibial run-off vessels had a considerable influence on long term patency rates. In severely ischaemic limbs, the limb salvage rate following this operation was 77 per cent. An analysis of symptoms, associated disease and complications is presented and discussed. No valid conclusions could be made regarding the effect of lumbar sympathectomy and postoperative anticoagulants on long term patency. This review has confirmed the findings of earlier studies that a satisfactory 5-year patency rate and a gratifying limb salvage rate can be achieved with an extremely low operative mortality rate of 0.37 per cent. Despite the presence of widespread atherosclerotic arterial disease, the 5-year mortality rate is 14.6 per cent, indicating that an attempt at reconstructive surgery is usually well worth while.