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1.
Polytetrafluoroethylene (PTFE) prosthetic bypasses in the lower extremity have poor patency rates, particularly in limb salvage cases. Patency and limb salvage rates of PTFE bypasses supplemented by distal interposition vein cuffs were assessed in patients requiring revascularization for critical limb ischemia, in the absence of a suitable autologous saphenous vein. Between October 1993 and April 1996, 163 patients underwent 185 infrainguinal bypasses. Forty-three limbs in 42 patients (12 women, 30 men; mean age 67 years) did not have a suitable autologous saphenous vein (24%) and had femoropopliteal (20) and infrapopliteal (23) bypasses performed. Patients were examined prospectively at 3-month intervals during the first year and at 6-month intervals thereafter to determine graft patency and limb salvage. Postoperative anticoagulation with warfarin was used in 26 patients. Indications for operation included limb salvage in 41 extremities (21 rest pain/ulceration or gangrene, 20 rest pain alone), and disabling claudication in two. Patients were followed clinically for 2–30 months (mean 10 months). Cumulative 2-year life-table patencies for all grafts, femoropopliteal and infrapopliteal bypasses were 64%, 75% and 62%, respectively. Previous primary patencies at the authors' institution for PTFE bypasses without vein cuffs were 35%, 46% and 12% for the same categories. Cumulative life-table limb salvage for all PTFE/vein cuff bypasses in the present series was 76% compared with 37% in previous PTFE bypasses without vein cuffs. Adjunctive use of distal interposition vein cuffs improves prosthetic graft patency, while producing satisfactory limb salvage. Postoperative anticoagulation did not influence graft patency. PTFE/vein cuff for lower-extremity revascularization shows good 2-year patency and is an acceptable alternate conduit in patients with critical limb ischemia when autologous saphenous vein is absent.  相似文献   

2.
In recent years many reports have attributed improved patency and improved vein utilization with lower extremity arterial bypass to infrapopliteal arteries to the use of the in-situ vein graft technique (ISVB). This report describes 110 reversed vein bypasses (RVB) to infrapopliteal arteries performed from 1980-1986. Thirty-three per cent of these patients did not have an intact ipsilateral greater saphenous vein. One hundred per cent of patients had autogenous RVB performed using a variety of techniques, including vein splicing, use of arm veins, lesser saphenous veins, branch veins, and use of graft origins distal to the common femoral artery. The life table patency figures for these grafts are 90%, 85%, and 85% at 1 year, 3 years, and 5 years, respectively. The life table limb salvage at 5 years is 93%. These figures for patency, vein utilization, and limb salvage for modern RVB to infrapopliteal arteries are clearly equal to or superior to any reported figures for ISVB. Results for RVB are greatly improved when compared with historic controls, as are results for ISVB. There is no evidence to date demonstrating superiority of one technique versus another.  相似文献   

3.
When a suitable single length of saphenous or arm vein is unavailable, the elderly patient with a profoundly ischemic extremity, poor runoff, and a distal outflow vessel frequently undergoes amputation. Rather than performing primary amputation or resorting to nonautogenous conduites, we used 21 different combinations of available vein segments of ipsilateral or contralateral greater saphenous, lesser saphenous, cephalic, and basilic veins as composite autogenous bypass grafts. Fifty-four extremities, of which 21 (39%) had one or more failed previous bypasses, were revascularized. Tissue necrosis necessitated operation in 74% (40 instances) and rest pain in 19% (ten instances). All grafts extended below the knee, 22% (12 grafts) to the infrageniculate popliteal artery, 78% (42 grafts) to an infrapopliteal runoff vessel, and 28% (15 grafts) to the ankle or foot. The patency rate at one month was 81%. Thrombectomy alone or with local graft repair increased the one-month patency rate to 96%. At one year, the patency and limb salvage rates were 74% and 82%, respectively.  相似文献   

4.
Over an 8-year period, we performed 93 lower extremity bypasses using complex autologous conduits, which included (1) contralateral greater saphenous vein (GSV), (2) composite GSV, (3) superficial femoral vein, (4) lesser saphenous vein, (5) cephalic or basilic veins, and (6) composite-sequential (PTFE and vein) grafts. These grafts represented 16% of all infrainguinal bypasses during this period, and all grafts were performed to treat limb-threatening ischemia. Survival, patency, and limb salvage were examined by the life-table method. Primary graft patency was 46 and 38% at 3 and 5 years. Assisted-primary patency was 62 and 59%, and secondary graft patency rates were 68 and 64% at 3 and 5 years. Twenty-nine bypasses (31%) required revision to restore or maintain patency. The 3-year limb salvage rate was significantly better when revision was performed for graft stenosis than for graft thrombosis (90% vs. 46%, p < 0.05). Overall limb salvage rate was 73% at 5 years. The mortality rate was 5.4% and the 5-year survival was 51%. Complex autologous tibial bypasses provided acceptable long-term limb salvage in patients with severe ischemia and inadequate ipsilateral GSV. The increased operating time and complexity required did not produce prohibitive operative risks. Postoperative graft surveillance in these complex vein bypasses allowed revision in many cases before graft occlusion occurred and significantly improved long-term limb salvage.  相似文献   

5.
During a 7-year period, 440 consecutive in situ saphenous vein grafts originating in the groin were performed in 371 patients, exposing the entire vein for valvulotomy with a modified Mills valvulotome. critical ischemia was the indication for bypass in 68%, and the distal anastomosis was to an infrapopliteal artery in 46%. Thirty-day operative mortality was 2.0%. Postoperative surveillance identified 18 stenotic grafts (4.1%), which were revised while still patent (primary revised patency); 36 grafts (8.2%) underwent revision after graft occlusion (secondary patency). Five-year life-table analysis showed overall primary revised patency of 78%, secondary patency of 83%, limb salvage of 88%, and patient survival of 66%. Femoroperoneal and inframalleolar bypasses fared well. The presence of diabetes did not diminish late graft patency. In contrast to reversed vein grafts, long infrapopliteal in situ grafts had long-term secondary patency similar to shorter femoropopliteal bypass grafts (p greater than 0.05). These results, coupled with the versatility and simplicity of the technique as used in the present series, suggest that in situ vein grafting is the procedure of choice for long infrapopliteal bypass.  相似文献   

6.
This report has presented the results of 329 reversed vein bypasses performed for lower extremity ischemia over a 6 3/4 year period. One hundred eighty-nine bypasses were formed from intact ipsilateral greater saphenous veins of adequate size and length. One hundred forty bypasses were formed in patients in whom the ipsilateral greater saphenous vein was absent or of inadequate size or length to complete the bypass. The grafts in these patients were accomplished using a variety of techniques including distal graft origin, use of arm veins and lesser saphenous veins, and use of vein splicing. The patency rates of these grafts were equivalent to those achieved using adequate intact ipsilateral greater saphenous vein. In view of these results, we conclude that the absence of a greater saphenous vein does not preclude successful autogenous lower extremity vein bypass and that prosthetic bypass is rarely justified.  相似文献   

7.
Initial laboratory and clinical evaluations of a new prosthetic material, expanded microporous polytetrafluoroethylene (PTFE), for small vessel replacement is promising and encourages further clinical trial. Frequently the autogenous saphenous vein is not available for bypass procedures, and alternative arterial substitutes have not proved reliable for replacement of small vessels. In this study, 15 patients with impending loss of limb and no available saphenous vein underwent revascularization of the lower extremity with expanded microporous PTFE grafts. Thirteen of 15 patients now demonstrate viable extremities with a resulting over-all early patency and limb salvage rate of 87 percent for this series. Follow-up ranges from one to 8 months. Seven patients had diabetes mellitus and eight had atherosclerotic heart disease. Nine grafts crossed the knee joint. In all patients arterial runoff was poor. Six patients had previous femoropopliteal bypasses, five with autogenous veins and one with Dacron velour. Two patients had multiple previous operations that failed, first with autogenous vein and later with fabric grafts. The current limb salvage and patency rate of 87 percent in high-risk patients suggests that expanded PTFE may be the prosthesis of choice when an autogenous vein is not available and possibly an equally good substitute when the venous autograft is available.  相似文献   

8.
The use of arm vein conduits during infrageniculate arterial bypass.   总被引:2,自引:0,他引:2  
T R Harward  D Coe  T C Flynn  J M Seeger 《Journal of vascular surgery》1992,16(3):420-6; discussion 426-7
To further examine the use of arm vein for bypass to the popliteal or infrapopliteal arteries, we retrospectively reviewed 43 patients undergoing infrageniculate arterial bypass by use of an arm vein as a conduit. Nine grafts were done to the below-knee popliteal artery and 34 to the infrapopliteal arteries. Six grafts were done by use of a single segment of an arm vein, whereas 37 grafts were composites of either multiple segments of arm vein (n = 19) or segments of saphenous and arm vein (n = 18). Mean follow-up time was 15 1/2 months. Initial (30-day) graft patency and limb salvage were 95%. Primary graft patency by life-table analysis was 67% at 1 year and 49% at 3 years. Follow-up examination detected graft stenosis before occlusion in six patients (all of whom were given anticoagulant medication) and three failing grafts were salvaged. This increased overall 3-year secondary graft patency to 64% and 3-year secondary patency for infrapopliteal bypasses to 66%. Eleven of 12 graft occlusions resulted in major amputations (eight were above the knee, and three were below the knee) so that limb salvage paralleled secondary graft patency (63% at 3 years). Thus arm veins provide an excellent alternative venous conduit for infrageniculate arterial bypass, even when composite venous grafts must be used.  相似文献   

9.
J E Edwards  L M Taylor  J M Porter 《Journal of vascular surgery》1990,11(1):136-44; discussion 144-5
During the last 9 years we performed 111 bypass procedures for lower extremity ischemia, which occurred after failed infrainguinal bypass grafting. An all autogenous reversed vein bypass was achieved in 103 of 111 operations (93%). Five-year primary and secondary patency of bypasses placed as treatment for one or more failed prior bypass(es) was 57% and 71%, respectively, as compared to 80% and 83%, respectively, for 5-year primary and secondary patency of simultaneously placed first time leg bypasses. Five-year limb salvage for bypass procedures performed as treatment for failed bypass was 90%, which was identical to that achieved for first time bypasses.  相似文献   

10.
PURPOSE: The purposes of this study were to evaluate the long-term results of different autogenous conduits used for infrainguinal bypass when ipsilateral greater saphenous vein (IGSV) is absent or inadequate and to determine the impact on the contralateral lower extremity. METHODS: The study was performed as a retrospective evaluation of a prospective vascular registry together with review of patient records and telephone follow-up. RESULTS: From January 1990 to June 2000, 226 autogenous infrainguinal reconstructions were performed in 203 patients without adequate IGSV. The patients consisted of 128 men and 98 women, with a mean age of 69 years. Prevalent risk factors included diabetes (51%) and prior coronary bypass (46%). Limb salvage was the predominant indication (93%), and 59% of the procedures were secondary reconstructions. All bypasses were completed with autogenous vein, which included contralateral greater saphenous vein (CGSV; 31%), single-segment lesser saphenous vein (5%), single-segment arm vein (19%), and autogenous composite vein (45%). Bypasses were performed to the tibial and pedal arteries in 84% of the cases. The 30-day mortality and graft occlusion rates were 1% and 9%, respectively. The overall postoperative morbidity rate was 24%, with a 7% rate of major complications. Follow-up was complete in 95% of patients over a mean period of 24 months (range, 0.1 to 106 months). The 5-year primary patency rates were significantly better for CGSV compared with autogenous composite vein grafts (61% +/- 7% versus 39% +/- 6%; P <.009). The 5-year secondary patency (60% to 73%) and limb salvage (78% to 81%) rates did not differ significantly between the three groups. Follow-up of the contralateral lower limb revealed that nine of 226 limbs (4%) were amputated at a mean of 36 months after the ipsilateral bypass. The overall 5-year contralateral limb preservation rate was 90% +/- 3%. Contralateral vein harvest and the presence of diabetes did not affect the need for bypass or amputation of the contralateral limb. CONCLUSION: For most patients with inadequate IGSV, the CGSV is the alternative conduit of choice because of its length, superior performance, ease of harvest, and minimal risk to the donor limb.  相似文献   

11.
A 10-year-experience of 217 femoropopliteal bypasses to isolated popliteal artery segments in 207 patients is reported. Thirty-three femoropopliteal bypasses (15%) were performed with reversed saphenous vein and 184 (85%) with polytetrafluoroethylene grafts. Operative indications were gangrene in 121 (56%), nonhealing ulceration in 40 (18%), ischemic rest pain in 51 (24%), and claudication in 5 (2%) cases. The 5-year primary graft patency rate of these bypasses was 59% (reversed saphenous vein, 74%; polytetrafluoroethylene, 55%; p less than 0.05), the secondary 5-year graft patency rate was 61% (reversed saphenous vein, 79%; polytetrafluoroethylene, 56%; p less than 0.05), and the 5-year limb salvage rate was 78% (reversed saphenous vein, 78%; polytetrafluoroethylene, 78%). The 30-day operative mortality rate was 10%, and the 5-year patient survival rate was 38%. Eleven patients (5%) required lower extremity amputation because of progressive gangrene or extensive infection despite a patent bypass to an isolated popliteal artery segment. We conclude that femoropopliteal bypasses to isolated popliteal artery segments (1) have acceptable 5-year graft patency and limb salvage rates; (2) should be performed with reversed saphenous vein grafts when possible; (3) may be performed with polytetrafluoroethylene grafts if necessary, with a resulting limb salvage rate equal to that of reversed saphenous vein grafts; and (4) require sequential extension to an infrapopliteal artery in up to 20% of patients. In addition, the presence of an isolated popliteal artery segment is associated with a high operative mortality rate and limited life expectancy because of coronary artery disease.  相似文献   

12.
Polytetrafluoroethylene (PTFE) bypasses were used in a series of arterial reconstructions to the popliteal artery (45) and to arteries below that level (11). These were performed in high-risk situations in patients who lacked a suitable saphenous vein. Vein bypasses were performed in a comparable series of high-risk situations in patients having a suitable autologous saphenous vein (45 to the level of the popliteal artery and 11 to an artery below that level). PTFE patency rates at 4-14 months were 43 to 45 (96%) for the femoro-popliteal reconstructions (with a limb salvage rate of 39 to 45 or 87%) and 5 of 11 (45%) for the distal bypasses. Saphenous vein bypass patency rates at 8-14 months were 39 of 45 (87%) for the femoropopliteal reconstructions (with a limb salvage rate of 36 of 45 or 80%) and 5 of 11 (45%) for the distal bypasses. These results justify continued use of PTFE grafts in patients without saphenous veins who require lower extremity arterial reconstructions for limb salvage. The exact place of PTFE grafts in arterial reconstructive surgery of the lower extremity definition based on longer periods of observation.  相似文献   

13.
Autologous saphenous vein (ASV) and polytetrafluoroethylene (PTFE) grafts were compared in 845 infrainguinal bypass operations, 485 to the popliteal artery and 360 to infrapopliteal arteries. Life-table primary patency rates for randomized PTFE grafts to the popliteal artery paralleled those for randomized ASV grafts to the same level for 2 years and then became significantly different (4-year patency rate of 68% +/- 8% [SE] for ASV vs. 47% +/- 9% for PTFE, p less than 0.025). Four-year patency differences for randomized above-knee grafts were not statistically significant (61% +/- 12% for ASV vs. 38% +/- 13% for PTFE, p greater than 0.25) but were for randomized below-knee grafts (76% +/- 9% for ASV vs. 54% +/- 11% for PTFE, p less than 0.05). Four-year limb salvage rates after bypasses to the popliteal artery to control critical ischemia did not differ for the two types of randomized grafts (75% +/- 10% for ASV vs. 70% +/- 10% for PTFE, p greater than 0.25). Although primary patency rates for randomized and obligatory PTFE grafts to the popliteal artery were significantly different (p less than 0.025), 4-year limb salvage rates were not (70% +/- 10% vs. 68% +/- 20%, p greater than 0.25). Primary patency rates at 4 years for infrapopliteal bypasses with randomized ASV were significantly better than those with randomized PTFE (49% +/- 10% vs. 12% +/- 7%, p less than 0.001). Limb salvage rates at 3 1/2 years for infrapopliteal bypasses with both randomized grafts (57% +/- 10% for ASV and 61% +/- 10% for PTFE) were better than those for obligatory infrapopliteal PTFE grafts (38% +/- 11%, p less than 0.01). These results fail to support the routine preferential use of PTFE grafts for either femoropopliteal or more distal bypasses. However, this graft may be used preferentially in selected poor-risk patients for femoropopliteal bypasses, particularly those that do not cross the knee. Although every effort should be made to use ASV for infrapopliteal bypasses, a PTFE distal bypass is a better option than a primary major amputation.  相似文献   

14.
During the past 4 years we have performed 239 reversed vein bypasses for leg ischemia in 196 patients including 45 to the above-knee popliteal artery, 118 to the below-knee popliteal artery, and 76 to infrapopliteal arteries. The cumulative primary patency results by the life-table method through 24 months are 97% at 6 months, 91% at 1 year, and 88% at 2 years. No difference was evident in patency rates with respect to site of distal anastomosis or reason for graft performance (i.e., for claudication [31%] or for limb salvage [69%]). Twenty-two percent of these patients did not have an intact ipsilateral greater saphenous vein. By a variety of techniques including the use of cephalic and lesser saphenous veins, vein splicing, and proximal superficial femoral endarterectomy, we have been able to perform autogenous vein bypass in 94% of all patients who require lower extremity revascularization. The patency of bypasses made from conduits other than greater saphenous vein does not differ from that of the entire series. Both the graft patency and vein utilization rates in the present report are equal to those of recently published series of in situ saphenous vein bypasses and are clearly better than the published results with reversed vein bypass a decade and more ago. We conclude that, although in situ saphenous vein bypass is a good procedure, it is not superior to reversed vein bypass performed in the same time period. This report again emphasizes the hazards of evaluating any new treatment by use of historic controls.  相似文献   

15.
We reviewed 239 infrapopliteal reversed greater saphenous vein graft bypasses placed for critical ischemia over a 7-year period to determine the influence of vein diameter on graft patency and limb salvage. Grafts were assigned to four groups based on the minimum external diameter measured during operation: less than 3.0 mm, n = 18; 3.0 mm, n = 59; 3.5 mm, n = 67; and greater than or equal to 4.0 mm, n = 145. A pattern of increasing graft patency and limb salvage among the four groups was noted as the minimum external diameter increased from less than 3.0 mm to greater than or equal to 4.0 mm. When compared to the larger grafts greater than or equal to 4.0 mm, primary graft patency was significantly lower both for less than 3.0 mm grafts (0% for less than 3.0 mm vs 65% for greater than or equal to 4.0 mm at 3 years, p less than 0.001) and for long (greater than 45 cm) 3.0 mm grafts (38% for long 3.0 mm vs 75% for greater than or equal to 4.0 mm at 2 years, p less than 0.005). All 3.5 mm and short (less than 45 cm) 3.0 mm grafts had patency rates similar to greater than or equal to 4.0 mm veins. Thus long 3.0 mm and all less than 3.0 mm reversed saphenous vein grafts should be considered at high risk for failure. Veins with fibrotic, thick-walled segments identified during operation (n = 19) had patency rates significantly lower than nonfibrotic veins (n = 270; p less than 0.01), and this may play a role in the failure of some less than 3.0 mm minimum external diameter vein grafts.  相似文献   

16.
Polytetrafluoroethelene (PTFE) is often utilized in patients with limb-threatening ischemia requiring infrainguinal revascularization in the absence of autologous saphenous vein. To increase long-term patency of PTFE grafts, vein interposition cuffs have been recommended as adjunctive procedures. The purpose of this study was to assess the efficacy of vein interposition cuffs on the long-term patency and limb salvage of patients requiring prosthetic bypass grafts for limb-threatening ischemia. Prosthetic bypass grafts with vein interposition cuffs (PTFE/VC) were performed on 56 limbs in 55 patients (32 men, 23 women; mean age of 67 years) from October 1993 to January 1998. Grafts were prospectively evaluated every 3 months for the first 12 months and biannually thereafter with duplex ultrasonography. PTFE/VC and PTFE bypasses at the popliteal level appear to have comparable patencies. However, PTFE/VC appear to offer an improved patency and limb salvage for infrapopliteal bypasses in patients with critical limb ischemia. When infrapopliteal revascularization is required in the absence of autologous saphenous vein, we recommend the use of PTFE with vein interposition cuffs.  相似文献   

17.
OBJECTIVE: The authors evaluated the long-term patency and outcome of patients undergoing infrainguinal reconstruction using the in situ saphenous vein. SUMMARY BACKGROUND DATA: The in situ saphenous vein bypass has demonstrated excellent patency and limb salvage rates in numerous studies. The authors previously reported their early results with these bypass procedures, and this article represents their long-term experience with 2058 in situ saphenous vein bypasses during a 20-year period. This comprises the largest series with long-term follow-up of in situ saphenous vein bypasses in the literature. METHODS: From 1975 to 1995, 3148 autogenous vein bypasses were performed at the authors' institution, of which 2058 used the saphenous vein in situ. The indication for operation was limb-threatening ischemia in 1875 of 2058 patients (91%). In 88% of patients with an intact ipsilateral saphenous vein, an in situ bypass was completed successfully. One thousand twenty-three bypasses (69%) were terminated at the infrapopliteal level. Of these bypasses, 1562 of 2058 (76%) were completed using the closed in situ technique. RESULTS: The 30-day patency rate was 96%, and the cumulative secondary patency was 91%, 81%, and 70% at 1, 5, and 10 years, respectively. Limb salvage rates using the in situ bypass were 97%, 95%, and 90% at 1, 5, and 10 years, respectively. CONCLUSION: The infrainguinal inflow source, length of bypass, specific outflow vessel, or vein diameter did not have a significant effect on immediate or long-term bypass performance. These data suggest that the in situ saphenous vein is an excellent conduit for femoropopliteal and femoral to infrageniculate bypasses for limb salvage.  相似文献   

18.
Early experience with popliteal to infrapopliteal bypass for limb salvage   总被引:1,自引:0,他引:1  
In an attempt to improve graft patency and limb salvage in patients with isolated tibial vessel and/or popliteal-tibial vessel occlusive disease, bypass grafts from the popliteal or distal superficial femoral artery to infrapopliteal arteries were used in patients requiring bypass for limb salvage. During a 2 1/2-year period, 23 patients with patent axial vessels and hemodynamically normal inflow to the level of the knee underwent such bypasses. Cumulative graft patency and limb salvage rates at 31 months were 84% and 70%, respectively. Five of the six patients who required below-knee amputation did so because of progressive gangrene in the presence of a patent bypass. Short bypasses between the popliteal and infrapopliteal arteries can significantly contribute to limb salvage in patients with tibial vessel occlusive disease and may be particularly useful in patients with saphenous veins too short for longer bypasses.  相似文献   

19.
The autogenous greater saphenous vein is the material of choice for infrainguinal arterial reconstructions. Substantial problems arise when this conduit is of poor quality or is absent because of earlier use. An alternative source for autogenous vein material are the upper extremities. In a retrospective study we compare 31 reconstructions with arm veins to 72 greater saphenous vein bypasses. In both groups quality control and valvulotomy were accomplished by using an angioscope. The two groups were similar concerning patient characteristic and results. The primary assisted patency rate in the arm vein group (93%, 36 months) did not differ significantly from the patency in the saphenous vein group (84%, 36 months, p=0.42). Similar results were seen for limb salvage. In conclusion, arm veins can be used as an adequate alternative to the greater saphenous vein in infrainguinal arterial reconstructions. Intraoperative quality control and postoperative follow-up are the keys achieving good long-term results.  相似文献   

20.
Forty lower limb bypasses using arm veins were performed on 37 patients. The indications for surgery were limb threat in 50% of cases, graft failure in 33%, aneurysms in 10% and claudication in 7%. Saphenous veins were absent because of prior use in 73% of cases, and because they were unsuitable in 27%. A single vein was used in 48%, 2 veins in 40% and 3 veins in 12% of cases. Seventy-four per cent of cases had a single-vessel run-off below the distal anastomosis. Eighty-two per cent of the distal anastomoses were to infrapopliteal arteries. The primary and secondary rates of these 40 bypasses at a mean follow-up of 14 months (range 1-40 months) were 74% and 90%, respectively. Limb salvage was 94%. Peri-operative morbidity and mortality were 23% and 3%, respectively. The anatomical and technical aspects of harvesting arm veins are critical to the success of this procedure and will be emphasised. We have found arm veins to be a durable source of accessible autogenous grafts for lower limb revascularisation in the absence of suitable saphenous veins.  相似文献   

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