Autogenous Saphenous Vein Research Articles

Autogenous saphenous vein versus PTFE bypass for above-knee femoropliteal reconstruction

Autogenous saphenous vein versus PTFE bypass for above-knee femoropliteal reconstruction

A retrospective analysis of infra-inguinal arterial reconstruction: three year patency rates.

Primary infra-inguinal arterial reconstructions were reviewed for primary patency and outcome of thrombosis in 144 patients. Distal anastomoses in these patients were to the popliteal artery and were above the knee in 63, below the knee in 53 and at the tibial level in 28. The treatment used was: polytetrafluoroethylene (PTFE) in 33 cases, PTFE with an interposition vein cuff in 29 cases, autogenous saphenous vein (ASV) in situ in 47 cases, and reversed technique in 26 cases. Life table analysis showed a 59% overall primary patency at 3 years. Patency rates of above knee anastomoses (65%) and below knee (61%) were statistically different from the tibial anastomoses (42%, P = 0.005). In both above and below knee popliteal anastomoses there was a statistically significant difference in the patency of ASV and the PTFE/vein cuff technique (P = 0.0006) but there was no difference between ASV and PTFE. There was no difference in patency rates for the various types of grafts with tibial anastomoses. Data were analysed at 3 years, taking into account the variables of smoking, diabetes or indications for surgery respectively and no difference was found in patency. The number and calibre of the run-off vessels did not influence patency significantly, hence anastomosis to any good quality vessel regardless of run-off is recommended. The poor results with the interposition vein cuff technique are unexplained but this study suggests that the technique should be reserved for anastomoses below the popliteal artery.

Saphenous vein patch rupture after carotid endarterectomy

From January 1983 to September 1990, 2731 carotid endarterectomies were performed at The Cleveland Clinic. Patch angioplasty with autogenous saphenous vein was used for arteriotomy closure during 1691 (62%) of these procedures and was associated with eight postoperative ruptures (0.5%) of the central portion of the patch in seven patients. This complication occurred in three men and in four women (mean age, 69 years), all of whom were hypertensive and all but one were smokers. Two patients (29%) had diabetes. In each case of patch rupture the vein had been harvested from the leg distal to the knee. Although the harvest site could not be determined retrospectively for every patient in this series, no patch ruptures were encountered among 370 procedures for which it could be documented that the saphenous veins had been obtained from the groin. All ruptures occurred within 5 days of the primary operations (including four during the first 24 hours) and were urgently corrected by primary closure of the original arteriotomy in two cases and by replacement of the ruptured patch in the remaining six. Two (29%) of the seven patients either died or sustained a permanent neurologic deficit. Central rupture of a saphenous vein patch is a rare but devastating complication after carotid endarterectomy. Since vein harvested from the lower leg or ankle may be marginally more likely to rupture than proximal vein from the thigh or groin, it should not be used indiscriminately for carotid patch angioplasty.

Saphenous vein patch rupture after carotid endarterectomy.

From January 1983 to September 1990, 2731 carotid endarterectomies were performed at The Cleveland Clinic. Patch angioplasty with autogenous saphenous vein was used for arteriotomy closure during 1691 (62%) of these procedures and was associated with eight postoperative ruptures (0.5%) of the central portion of the patch in seven patients. This complication occurred in three men and in four women (mean age, 69 years), all of whom were hypertensive and all but one were smokers. Two patients (29%) had diabetes. In each case of patch rupture the vein had been harvested from the leg distal to the knee. Although the harvest site could not be determined retrospectively for every patient in this series, no patch ruptures were encountered among 370 procedures for which it could be documented that the saphenous veins had been obtained from the groin. All ruptures occurred within 5 days of the primary operations (including four during the first 24 hours) and were urgently corrected by primary closure of the original arteriotomy in two cases and by replacement of the ruptured patch in the remaining six. Two (29%) of the seven patients either died or sustained a permanent neurologic deficit. Central rupture of a saphenous vein patch is a rare but devastating complication after carotid endarterectomy. Since vein harvested from the lower leg or ankle may be marginally more likely to rupture than proximal vein from the thigh or groin, it should not be used indiscriminately for carotid patch angioplasty.

POPLITEAL ARTERIAL ANEURYSM ASSOCIATED WITH MEDIAL MUCOID DEGENERATION

An experience with popliteal arterial aneurysm associated with medial mucoid degeneration is described, A 37-year-old male visited a nearby practitioner because of paresthesia in the right foot.He was pointed out having a pulsatile mass and referred to our hospital.Ultrasonography, CT, and angiography showed a right popliteal aneurysm with intramutal thrombosis. AT operation, the aneurysm was transected and vascular reconstruction was performed by the end-to-end anastomosis of autogenous saphenous vein. Pathological examination showed medial mucoid degeneration, where smooth muscle and elastic fibers decreased. There were also no findings of arteriosclerosis and inflammatory infiltrates. This popliteal arterial aneurysm is supposed to be classified as arterial dysplasia reported by D. Melliere.

Remote Arteriovenous Fistula with Infrapopliteal Polytetrafluoroethylene Bypass for Critical Ischemia

Between January 1985 and January 1989, 13 patients underwent femorotibial bypass using a polytetrafluoroethylene graft with a remote distal arteriovenous fistula. Indications for operation were gangrene in six patients, rest pain in five patients, and nonhealing ulcer in two patients. No patient had a usable autogenous saphenous vein. Eight patients had a previous failed femorodistal bypass. Standard femorotibial bypass was performed using a 6 mm thin-walled polytetrafluoroethylene graft. The distal remote arteriovenous fistula was done on the same artery. Warfarin was given postoperatively. Graft patency was assessed by duplex scan and digital arteriography. There was no postoperative mortality. All grafts and fistulas remained patent initially with improvement in symptoms and limb salvage. In the follow-up period there was continued graft patency in all but two patients who had a below-knee amputation. Three patients died with a patent graft. In two additional patients the graft remained patent but the fistula closed. We believe that in selected situations, the remote distal arteriovenous fistula is a potentially valuable adjunct for obligatory polytetrafluoroethylene femorotibial bypass.

Factors affecting the patency of small-caliber prostheses: Observations in a suitable canine model

Lack of an endothelial surface is most often blamed for the relatively poor patency of polytetrafluoroethylene grafts used in infrageniculate bypass when compared to autogenous saphenous vein. Length, caliber, flow, and ability to withstand flexion are also acknowledged but have not been systematically examined. We report the results of our attempts to discriminate between the relative contributions of these factors and to develop a suitable canine model for evaluating small-caliber prostheses (4 mm × 10 cm thin-walled polytetrafluoroethylene). ASA/dipyridamole were given 1 week before and 4 weeks after operation. Patency was assessed by directional Doppler at frequent intervals (≤ 3 days). The following were observed: (1) Iliac placement provided a useful patency reference point (40% to 50% patency at 60 days). (2) Carotid patency was not better than iliac patency. (3) Crossing a flexion crease decreased patency. (4) The low patencies were not technical but intrinsic to the graft. Iliofemoral vein grafts achieved 100% patency at 60 days. (5) External rings did not improve iliofemoral patency (equal in paired comparisons). (6) Neither baseline platelet aggregation nor platelet aggregation after ASA administration correlated with patency. This canine model is an excellent test for small caliber-low flow prostheses. It allows paired-site comparisons, which are essential, and meaningful patency data with reasonable numbers of subjects within 2 months' observation. Directional Doppler evaluation avoids need for angiography or serial postmortem analysis sacrifice.

Factors affecting the patency of small-caliber prostheses: Observations in a suitable canine model

Lack of an endothelial surface is most often blamed for the relatively poor patency of polytetrafluoroethylene grafts used in infrageniculate bypass when compared to autogenous saphenous vein. Length, caliber, flow, and ability to withstand flexion are also acknowledged but have not been systematically examined. We report the results of our attempts to discriminate between the relative contributions of these factors and to develop a suitable canine model for evaluating small-caliber prostheses (4 mm x 10 cm thin-walled polytetrafluoroethylene). ASA/dipyridamole were given 1 week before and 4 weeks after operation. Patency was assessed by directional Doppler at frequent intervals (less than or equal to 3 days). The following were observed: (1) Iliac placement provided a useful patency reference point (40% to 50% patency at 60 days). (2) Carotid patency was not better than iliac patency. (3) Crossing a flexion crease decreased patency. (4) The low patencies were not technical but intrinsic to the graft. Iliofemoral vein grafts achieved 100% patency at 60 days. (5) External rings did not improve iliofemoral patency (equal in paired comparisons). (6) Neither baseline platelet aggregation nor platelet aggregation after ASA administration correlated with patency. This canine model is an excellent test for small caliber-low flow prostheses. It allows paired-site comparisons, which are essential, and meaningful patency data with reasonable numbers of subjects within 2 months' observation. Directional Doppler evaluation avoids need for angiography or serial postmortem analysis sacrifice.

ALLOGRAFT VEIN PATENCY IN A CANINE MODEL

Autogenous saphenous vein is the preferred conduit for many cardiovascular operations. Attempts to use allograft veins for arterial reconstruction have had poor results. To define circumstances under which allograft veins might prove to be acceptable vascular conduits, dogs underwent femoral artery bypass using reversed saphenous veins. Veins were transplanted fresh or after cryopreservation. Group I dogs received a fresh autograft to replace one femoral artery (group I F) and a cryopreserved (CP) autograft (group I C) to replace the other. Group II dogs received fresh allograft veins, and group III received CP allograft veins, neither group receiving additional treatment. Group IV received fresh allograft veins and Group V received CP allograft veins; both groups received cyclosporine 15 mg/kg. Animals were maintained until grafts occluded or until six months elapsed. Patency was observed in all group I F grafts throughout the observation period. Six-month patency rates in the other groups were: group I C, 9/10 (P = NS vs. group I F); group II, 0/10 (P less than 0.01), group III, 0/10 (P less than 0.01), group IV, 1/10 (P less than 0.01), group V, 7/11 (P = NS). In a separate series of observations 10 cryopreserved allograft veins were implanted in 10 dogs that received CsA for 30 days. CsA was then discontinued. All of these grafts occluded within 30 days of discontinuing the CsA. Long-term patency of saphenous vein allografts was achieved only with the combination of cryopreservation and immunosuppression with continued CsA.

A utilização da artéria torácica interna aumenta a mortalidade hospitalar do paciente coronariano idoso revascularizado?

No InCor, foi elaborado um protocolo para avaliar se o emprego da artéria torácica interna alterava a mortalidade hospitalar nos pacientes coronarianos idosos (idade > 70 anos), submetidos a revascularizaçáo isolada, eletiva do miocárdio. No protocolo foram incluídos parâmetros clínicos, hemodinâmicos, radiológicos, operatórios e de pós-operatório. Foram analisados 100 pacientes consecutivos, com observações completas, em estudo prospectivo. A análise estatística foi realizada pelo teste de X² de Pearson. Concluímos que houve diferença estatística entre os grupos comparados e que a mortalidade hospitalar foi maior no grupo de pacientes nos quais se utilizou o enxerto de veia safena autógena. Atribuiu-se ao cirurgião, como triador, a obtenção de tais resultados, utilizando a artéria torácica interna naqueles pacientes em melhor estado geral.

In situ fresh allograft replacement of an infected aortic prosthetic graft: Eighteen months' follow-up

We report a case in which an allogenic aortic graft was used to treat the last one of a series of infectious graft complications. The original operation was a Dacron aortobifemoral bypass for aortoiliac occlusive disease in an institution other than ours. The patient was referred for the treatment of the infection of the prosthetic implant. We inserted a prosthetic bypass from the left axillary to the left deep femoral artery, as well as a crossover autogenous saphenous vein graft from the prosthesis to the right deep femoral artery; in the same operation the infected intraabdominal prosthesis was removed with closure of the proximal aortic stump. Subsequent stenosis of the vein graft made it necessary to insert a prosthetic bypass between the descending thoracic aorta and the two deep femoral arteries. Infection of the last named prosthesis made it necessary to remove it and replace it with a tailored allogenic arterial allograft between the infrarenal abdominal aorta and both deep femoral arteries. The patient had an uneventful recovery as the infection was controlled and both lower limbs were salvaged. Eighteen months later the allograft was patent without any signs of degeneration. Further clinical experience under appropriate conditions may prove the use of allografts effective in the treatment of selected cases of aortic prosthetic infection.

Long-term Results of Coronary Bypass Surgery Analysis of 1698 Patients Followed 15 to 20 Years

Between 1968 and 1975, 1698 patients underwent coronary artery bypass with autogenous saphenous vein and were followed for up to 20 years. Age at operation was 53.9 +/- 8.4 years, and 1485 were men (88%). Angina was present in 1637 patients (96%). There was single-vessel disease in 306 patients (18%), double-vessel in 642 (38%), triple-vessel in 550 patients (32%) and left main stenosis in 200 (12%). Preoperative left ventricular quality was good in 1185 (70%), poor in 508 (30%), and unknown in five patients. Survival at 20 years was as follows: for single-vessel disease, 40%; double-vessel, 26%; triple-vessel, 20%; and left main, 25%. At 20 years of follow-up, 67% of surviving patients were asymptomatic and 26% were improved. Antianginal drug therapy consisted of nitrates in 49% of patients and beta-blockers in 26%. Graft patency at 0 to 5 years was 633 of 780 grafts (81%); at 6 to 10 years, 415 of 606 grafts (68%); at 11 to 15 years, 271 of 449 grafts (60%); and at 16 to 20 years, 65 of 140 grafts (46%). Coronary bypass reoperation was performed in 324 patients (19%) and survival of these patients was 62% compared to 37% for nonreoperation patients (p less than 0.05). Cox analysis demonstrated that the major determinants of survival related to age at operation, extent of coronary disease, quality of ventricle, history of stroke, and preoperative congestive heart failure. At 20 years of follow-up of this early experience with coronary bypass, 76% of surviving patients had one or more patent grafts and the probability of freedom from reoperation was 0.62.

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)

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 KCI, prostaglandin F2α, 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. These results suggest the following: (1) cryopreservation does not influence early patency rates, blood flows or platelet deposition in autogenous vein grafts; (2) functional nerve terminals are not present in fresh or cryopreserved autogenous vein grafts after 4 weeks; (3) an endothelium-derived relaxing factor is present in both fresh and cryopreserved autogenous vein grafts at 4 weeks. It remains to be determined as to whether the increased endothelial contractile responses and decreased relaxations of the smooth muscle of cryopreserved autogenous grafts would influence long-term patency of these grafts.

Effect of desmopressin on vein graft patency in a microvascular model

Desmopressin acetate decreases blood loss after cardiac surgery by activating platelets. We studied whether this effect was detrimental to small-caliber vein grafts in rats. Thirty minutes before femoral artery grafting with 0.75-mm-diameter reverse autogenous saphenous vein grafts, 20 rats received desmopressin acetate intravenously at 1.0 micrograms/kg over 10 minutes, and 20 control rats received normal saline intravenously over 10 minutes. In each group, 10 rats received a 6-mm-long graft and 10 an 18-mm-long graft. Graft patency was evaluated at 20 minutes, 24 hours, and 30 days. Intimal thickening was assessed by light and scanning electron microscopy. At 30 days, 9 short grafts and 8 long grafts in the desmopressin-treated group were patent, whereas only 8 short control grafts and only 6 long control grafts were patent. Intimal thickening and platelet deposition were the same in both groups. These data show no detrimental effects of desmopressin acetate on saphenous vein graft patency.

Current techniques for infrainguinal arterial reconstruction

Infrainguinal reconstruction for peripheral vascular occlusive disease comprises an increasingly complex array of interventions which provide unparalleled options for the salvage of threatened limbs. Conventional autogenous saphenous vein bypass remains the most durable revascularization with anticipated graft patency rates approaching 80 percent after five years and excellent long term limb salvage. These excellent results are equally applicable to vein grafts carried to infrapopliteal and even inframalleolar levels, possibly reflecting increased utilization of the in situ method. Although 20 per cent of grafts fail within five years, secondary intervention results in sustained limb salvage in the majority of patients. In the absence of autogenous vein, however, prosthetic material performs poorly such that new interventions consisting of percutaneous transluminal angioplasty, rotary atherectomy devices and laser systems are under aggressive development. Although initial results with these devices are encouraging, long term patency rates remain poor largely due to restenosis. Further progress seems to depend primarily on an increased understanding of the natural healing response of the injured artery.

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.

Development and application of modern devices in vascular surgery including comment on modern antithrombotic and lytic drug therapy.

Since modern vascular surgery started with the discovery of heparin and the development of modern vascular grafts including autogenous saphenous vein, the speciality has been technologically driven. At the outset, vascular surgery depended almost entirely on the development of specialized clamps, instruments, and tools to permit decisive attack on the problems of occlusion. No less important was the development of insight into the basis of atherosclerosis, the discovery that atherogenesis with thrombosis is electrochemically identical to corrosion in pipes and therefore subject to chemical forces, which have not yet been delineated, as well as mechanical forces which have been delineated and permit one to attack the atheroma directly. Thus, classic replumbing techniques including bypass and endarterectomy have long been a part of the fundamental firmament of vascular surgery. Most recently, modern techniques in cleaning out blood vessels, removing occlusive processes, and modern thrombus-dissolving enzymes have all come to the forefront. Frequently multiple techniques are used simultaneously. This article is an attempt to summarize various aspects of this activity and describe several of the patents which have been seminal in the ultimate application of the techniques in both experimental animals and man. This should be the first of a series of efforts to summarize this area. The process of change has never been more kinetic than now.

Small Intestinal Submucosa as a Small-Diameter Arterial Graft in the Dog

Autogenous saphenous vein, human umbilical vein, modified bovine collagen, Dacron, and PTFE have been used as small-diameter arterial grafts with moderate success. We tested autogenous small intestine submucosa as a small-diameter arterial graft in both a carotid and femoral artery (mean ID 4.3 mm) of 18 dogs (total of 36 grafts). All dogs received aspirin and warfarin sodium for the first 8 weeks after surgery. Graft patency was evaluated by Doppler ultrasound techniques and angiography. Two grafts ruptured and 5 grafts occluded by 21 days after surgery. One graft became occluded at 14 weeks. Fifteen dogs were sacrificed at periodic intervals until 48 weeks after surgery. Patent grafts had no evidence of infection, propagating thrombus, or intimal hyperplasia. Graft aneurysmal dilation occurred in 4 grafts (11%). The grafts were composed of a dense organized collagenous connective tissue with no evidence of endothelial cell growth on the smooth luminal surface. Three dogs are alive at 76 to 82 weeks after surgery. Overall, graft patency was 75%. Graft patency after cessation of anticoagulation therapy was 92.3% (12 of 13 grafts). We conclude that autogenous small intestinal submucosa can be used as a small-diameter arterial graft in the dog and is worthy of further investigation.

Extraanatomic bypass for peripheral arterial injuries

Over an 8-year period, extraanatomic bypass grafting was performed for peripheral arterial injuries or infections in 12 patients. The indications for use of the technique were as follows: (1) extensive loss of soft tissue over arterial injury or avulsion; (2) wound infection with rupture of a previous arterial repair, or (3) combined infections in soft tissue and the underlying artery due to illicit drug injection. The technique involved excision of the injured or infected artery beyond the margins of the debrided wound and insertion of an autogenous saphenous vein as an extraanatomic bypass graft in a medial or lateral position around the wound. Shotgun wounds were the mechanism of injury in six patients, whereas an extensive injury or infection in the brachial artery was present in eight patients. Successful wound coverage or closure was accomplished and distal arterial flow preserved in 11 patients, 5 of whom had residual neuromuscular or bony defects related to the magnitude of the original injury.