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S Salles-Cunha

Publications and source records attributed to S Salles-Cunha.

At least 19 recordsLinked to original sources
PubMed2003

Hemodynamics of infrapopliteal PTFE bypasses and adjunctive arteriovenous fistulas.

PURPOSE: Blood flow, pressure and peripheral resistance in patients with established polytetrafluoroethylene (PTFE) grafts and adjunctive arteriovenous fistulas (AVF) have rarely been investigated. To better elucidate the effects of this AVF, we obtained noninvasive measurements of hemodynamic variables in patients with infrapopliteal PTFE grafts and an AVF. METHODS: . Systolic, mean and diastolic arm and toe pressures were measured with an oscillometric technique employed in automatic blood pressure monitors. Peak-systolic velocity, end-diastolic velocity and flow rates at the graft and recipient distal artery were measured with duplex ultrasound. Resistance for the leg and foot in peripheral resistance units ( PRU ) was estimated as mean arm pressure divided by graft flow rate and as mean toe pressure divided by distal artery flow rate respectively. We analyzed data from 21 patients. Toe pressures were measurable in 13 patients. Bypass graft inflow was at the external iliac artery in 11 patients, common femoral in six, common iliac in two and superficial femoral in two. The distal anastomosis was at the anterior tibial artery in 10 patients, peroneal in seven and posterior tibial in four patients. RESULTS: . Graft systolic and diastolic velocities were 91+/-46 (mean+/-sd) and 38+/-31 (mean+/-sd) cm/s respectively. Toe systolic pressure averaged 81+/-28 (mean+/-SD) mmHg with a corresponding toe/brachial index (TBI) of 0.53+/-0.18 (mean+/-SD). The ratio between arm mean pressure, 104+/-20 (mean+/-SD) mmHg, and graft flow rate, 413+/-290 (mean+/-sd) ml/min, yielded an estimated leg resistance of 0.32+/-0.20 peripheral resistance units (PRU) (mean+/-sd). The ratio between mean toe pressure, 51+/-21 (mean+/-SD) mmHg, and distal artery flow rate, 37+/-26 (mean+/-SD) ml/min, produced an estimated foot resistance averaging 1.66+/-1.18 PRU (mean+/-sd). CONCLUSIONS: Average graft flow rate was five times greater than flow reported for standard tibial bypasses. Although distal artery flow rate and graft peak systolic velocity were within reported normal ranges, mean toe pressure and toe-brachial index were below normal. Leg and foot resistances were decreased. These data suggest that bypasses with arteriovenous fistulas have increased flow, desirable for graft patency, but may affect distal perfusion pressure.

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PubMed2001

Routine preoperative carotid duplex scanning in patients undergoing open heart surgery: is it worthwhile?

It has been reported that carotid screening may be cost-effective in patient populations in which the prevalence of severe carotid stenosis exceeds 4.5%. In order to identify potential patient populations who might benefit from carotid screening, we examined the results of preoperative duplex scanning in patients undergoing open heart surgery. Between January 1995 and July 1998, 3708 patients (59% male, 41% female) underwent open heart surgery at our institution. Of these, 3081 underwent coronary artery bypass grafting (CABG), 364 underwent valve replacement (VR), and 263 underwent CABG and VR. The ages of these patients ranged from 40 years to 98 years (mean 68 +/- 11 years). The risk factors analyzed included hypertension (HTN), 59%; smoking (Smk), 53%; and diabetes (DM), 33%. Patients were divided into three groups according to their age. Group A consisted of the 835 patients who were < or = 60 years old, group B consisted of 2474 patients ranging from 61 years to 80 years old, and group C consisted of 399 patients who were > or = 81 years old. All patients underwent bilateral preoperative carotid duplex scans at an Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL)-accredited vascular laboratory. Statistical analyses were performed using chi-squared, Fisher's exact test, linear regression, and multivariate analysis. From our results we concluded that carotid screening is not recommended for patients under 60 years of age who are undergoing CABG unless they present with a minimum of two of the following major risk factors: hypertension, diabetes, or smoking. However, carotid screening is recommended for all patients undergoing open heart operations who are over the age of 60 years old, regardless of the absence of associated risk factors.

Adult↗
PubMed2001

Noninvasive ultrasound measurement of shear rate in leg bypass grafts.

Shear has been implicated in the etiology of atherosclerosis, thrombosis and graft stenosis. We measured shear rate noninvasively in infrainguinal bypasses. Velocity profiles were recorded from 35 femoropopliteal and 40 tibial grafts. Flow rate (Q), systolic shear rate (SSR), diameter, and bluntness factor (BF) were measured at midgraft using ultrasound (US). Mean shear rate (MSR) was calculated from flow and diameter. SSR, 671 +/- 260 (SD) vs. 659 +/- 304 s(-1) (p = 0.85), and MSR, 168 +/- 84 vs. 193 +/- 110 s(-1) (p = 0.26), were similar for popliteal and tibial bypasses, but differences in Q, 126 +/- 57 vs. 104 +/- 38 mL/min, were borderline significant (p = 0.058). Popliteal grafts had larger diameters, 5.2 +/- 1.1 mm vs. 4.7 +/- 0.8 mm (p = 0.048), and BF, 3.4 +/- 0.9 vs. 2.8 +/- 0.7 (p = 0.0014). Shear rates were obtained noninvasively in humans. Larger diameters in popliteal vs. tibial bypasses did not result in lower shear rates and were compensated for by larger bluntness factors. Velocity profile bluntness cannot be ignored in shear rate analysis.

Adult↗
PubMed2001

Posterior transverse plication technique for treatment of redundant internal carotid artery during endarterectomy.

PURPOSE: Posterior transverse plication (PTP) has gained popularity as a technique to correct redundancy of the internal carotid artery during endarterectomy. The safety of this technique in large series of patients has not been extensively studied. We investigated 876 primary carotid endarterectomies (CEAs) performed at our institution over the last six years to determine the safety of this technique. METHODS: Indication for surgery was carotid stenosis >/=70% in 341 (39%) symptomatic and 535 (61%) asymptomatic cases. Preoperative imaging consisted of duplex ultrasound alone or combined with magnetic resonance angiography. Patients were divided into four groups related to surgical technique: CEA+PTP+8mm patch (group Ia), CEA+PTP+10mm patch (group Ib), CEA+patch (group II) and CEA+primary closure (group III). There were 43, 39, 581 and 213 patients in groups Ia, Ib, II and III, respectively. No statistical differences in age, sex or risk factors for atherosclerotic disease were noted among the groups. Postoperative duplex ultrasonography was used at 2weeks and every 6months thereafter to evaluate the adequacy of the repair and presence of complications such as pseudoaneurysm formation and extrinsic compression by the excluded carotid segment. RESULTS: The 30-day mortality was 1.2%, 0.6% and 0.3% for groups I, II and III, respectively. Stroke rates for the same period were 0%, 0.6% and 0.8% for groups I, II and III, respectively. Duplex ultrasonography demonstrated significant stenosis (>/=50%) in two (5%) patients in group Ia at 12months. No restenosis was observed in group Ib. For groups II and III the rates of restenosis were 1.5% and 0.8%. One patient in group II developed a pseudoaneurysm after 7months. CONCLUSION: Posterior transverse plication safely corrects redundancy of the internal carotid artery during endarterectomy without causing early significant restenosis. Continued follow-up in a larger group of patients to determine long-term efficacy and correlation between patch size and restenosis rate is warranted.

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PubMed2000

Upper extremity deep venous thrombosis: an underrecognized manifestation of a hypercoagulable state.

Although lower extremity deep venous thrombosis (LEDVT) has been associated with a hypercoagulable state, there are scant data available for patients presenting with upper extremity deep venous thrombosis (UEDVT). Therefore, we conducted a prospective study to determine whether such an association exists for UEDVT. Fifty-two patients who presented with UEDVT at our institution from August 1996 to June 1997 underwent a hematological profile consisting of activated protein C (APC) resistance, antithrombin III (ATIII) level and activity, factor V mutation (arginine 506 to glycine), protein C level and activity, protein S level and activity, factors II and X activity, lupus anticoagulant, and cardiolipin antibody. This represented 68% (52/76) of the total number of patients in whom the diagnosis of UEDVT was made by duplex ultrasonography during this time period. The ages ranged from 9 to 97 (mean 63 +/- 23 years). There were 22 males and 30 females. Twenty-five patients (48%) had a central venous line in place, 4 patients (8%) had a pacemaker, 14 patients (27%) had a history of neoplasm, and 7 patients (13%) had concomitant LEDVT. The results of our study showed that a hypercoagulable state may be an underappreciated contributing factor in the development of UEDVT. Contrary to prior belief that three sets of tests are needed to confirm the presence of a hypercoagulable state, these data also suggest that only two tests may be needed.

Adolescent↗
PubMed2000

Lower-extremity revascularisation without preoperative contrast arteriography in 185 cases: lessons learned with duplex ultrasound arterial mapping.

PURPOSE: we have previously reported our experience with lower-extremity duplex-ultrasound arterial mapping (DUAM) compared to contrast arteriography (CA) to predict lower-extremity bypass sites. The present study evaluates arterial revascularisation procedures for chronic limb ischaemia based on DUAM. MATERIALS AND METHODS: from January 1998 to July 1999, 195 patients (128 men, 67 women) underwent 211 lower-extremity revascularisation procedures based on DUAM. Indications for surgery were tissue loss, severe claudication, rest pain and popliteal aneurysm in 57%, 25%, 14% and 4% of the limbs, respectively. The mean age was 72+/-12 years and risk factors such as diabetes, hypertension, tobacco use, coronary artery and end-stage renal disease were present in 53%, 58%, 53%, 50% and 12% of the patients, respectively. Previous revascularisation procedures had been performed in 23% of the limbs. Preoperative evaluation consisted of DUAM alone (185) or of a combination of DUAM and CA (29 limbs). CA was deemed necessary due to a combination of technical difficulties that jeopardized adequate sonographic imaging and presence of disadvantaged run-off for medico-legal reasons. DUAM consisted of direct imaging of all major arteries from the distal aorta to the pedal circulation. Optimal inflow and outflow bypass anastomotic sites were selected according to a diagram based on DUAM. Adequacy of the inflow was additionally assessed by common-femoral-artery waveform and confirmed by intraoperative pressure measurements. Post-bypass CA was obtained to verify patency of the run-off. RESULTS: DUAM procedure time averaged 75+/-26 min. For patients who underwent only DUAM, the distal anastomosis was to the popliteal artery in 91 cases and to tibial or pedal arteries in 58 cases. Distal anastomosis was proximal to a significant lesion in two cases that required jump grafts. Cumulative patency rates at 1 and 3 months for popliteal bypasses were 96% and 90%, and for infrapopliteal bypasses 90% and 83%, respectively. Inflow procedures to the femoral artery, patch and balloon angioplasties accounted for the remaining 40 cases. Four primary amputations were performed after CA confirmed DUAM findings. CONCLUSIONS: contrary to general belief, these data show that high-quality arterial ultrasonography represents a safe alternative to preoperative CA, even for infrapopliteal bypasses. This non-invasive approach may be especially useful for patients with contrast allergy or impaired renal function.

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PubMed1999

Carotid screening with duplex ultrasound in elderly asymptomatic patients referred to a vascular surgeon: is it worthwhile?

The purpose of this study is to prospectively determine the outcome of carotid duplex ultrasound screening in patients referred to a vascular surgeon for problems other than carotid disease. During a recent 12-month period, 307 patients age 65 years and older (mean 76 +/- 8 years) were referred to one vascular surgeon for problems other than cerebrovascular disease. Fifty-one percent of the patients were male, 49% were female, 32% were diabetic, 32% were hypertensive, 31% smoked, 20% had coronary artery disease, and 64% had peripheral arterial occlusive disease. All patients underwent a screening duplex ultrasound exam of the carotid arteries as approved by our Institutional Review Board. The results of our study showed that the prevalence of asymptomatic carotid artery stenosis >70% among patients seen by a vascular surgeon for problems other than cerebrovascular disease is high (21%) and is associated with male gender, advanced age, diabetes mellitus and having quit smoking. Continued carotid artery duplex screening is warranted in this patient population greater than age 65 years.

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PubMed1999

The use of duplex ultrasound arterial mapping as an alternative to conventional arteriography for primary and secondary infrapopliteal bypasses.

BACKGROUND: For more than 1 decade, duplex ultrasonography has been investigated as a potential replacement for invasive contrast arteriography (CA) prior to lower extremity revascularization. While some authors advocate the reliability of this methodology for infrainguinal imaging, revascularizations based on duplex ultrasonography alone are seldom reported. Our initial experience with duplex ultrasound arterial mapping (DUAM) for primary and secondary infrapopliteal bypasses performed without preoperative CA is reported in this series. METHODS: Twenty-eight infrapopliteal bypasses based on DUAM alone (26) and combined DUAM and CA (2) were performed. Indications for surgery were tissue loss in 22 cases and rest pain in 6. Eight patients (29%) had at least 1 previous ipsilateral revascularization. A schematic anatomical drawing based on DUAM helped the selection of optimal inflow and outflow bypass sites. Bypasses originated from the femoral arteries in 17 cases, external iliac in 3, and popliteal in 4, and from a previous graft in 4. The distal anastomosis was to the dorsalis pedis in 12 cases, posterior tibial in 7, anterior tibial in 6, and peroneal in 3. RESULTS: DUAM revealed unobstructed inflow in 24 cases, significant iliac stenosis in 1, and in 3 cases imaging was not possible owing to obesity. A pressure gradient of 15 mm Hg between donor and radial artery confirmed the stenosis diagnosed by DUAM, and was successfully treated with balloon angioplasty and stent placement. A single infrapopliteal runoff artery was identified by DUAM in 22 cases, 2 in 4 cases, and 3 in 2 cases. Preoperative CA was performed in 2 instances because of severe arterial calcification. Completion arteriography matched the run-off status predicted by DUAM in 25 out of 26 cases (96%). DUAM missed a significant anterior tibial artery stenosis that required a distal graft extension. One-, 3-, and 6-month patency rates were 96%, 85%, and 62%, respectively. Limb salvage rate was 86%. CONCLUSIONS: This early experience shows that DUAM may be a safe alternative to invasive conventional arteriography for the majority of patients (89%) presenting with critical ischemia and in need of infrapopliteal bypasses.

Adult↗
PubMed1998

Ultrasound echogenicity in experimental venous thrombosis.

This study characterizes the echogenicity of experimentally induced venous thrombosis. Venous duplex imaging (Diasonics Spectra) was performed of the rat (n 12) and primate (n 3) inferior vena cava (IVC). Thrombosis was induced by IVC ligation at the level of the renal veins (rat, baboon) or balloon occlusion (baboon) of the IVC at the renal vein and iliac vein bifurcation level. Sham-treated rats served as controls. B-mode images were stored for off-line computer analysis. Fixed depth gain control curves allowed for measuring gain-corrected echogenicity units over the IVC in both a longitudinal and transverse orientation. In rat studies, thrombus was removed at time of euthanasia and dissolved, allowing for fibrin monomer determination using a chromogenic assay. Echogenicity values generally increased over time in both rat and primate studies. Significant differences between ligated and sham-treated rats were noted at each time point measured (6 h, 2 days, and 6 days after IVC ligation) and fibrin monomer values correlated (p < 0.05) with echogenicity units. In primate studies, echogenicity values significantly were different from baseline values at all time points measured (6 h, 2 days, 6 days, and 13 days after thrombus induction). Duplex ultrasound can be used to quantitate thrombus echogenicity, which correlates to fibrin content. Such measurement may potentially allow for improved thrombus age determination and the noninvasive quantitation of thrombus progression/resolution.

Animals↗
PubMed1998

The effect of tumor necrosis factor binding protein and interleukin-1 receptor antagonist on the development of abdominal aortic aneurysms in a rat model.

PURPOSE: Tumor necrosis factor (TNF), interleukin 1 (IL-1), and matrix metalloproteases have been noted to be elevated in human abdominal aortic aneurysms (AAAs) as compared with normal and occlusive aortic disease. Because TNF and IL-1 have been shown to cause release of proteases that weaken the aortic matrix, it has been suggested that these cytokines may play a central role in the aortic dilatation process. To substantiate this hypothesis, we investigated the effects of TNF and IL-1 antagonists, tumor necrosis factor binding protein (TNF-BP) and interleukin-1 receptor antagonist (IL-1RA), on the development of AAAs in a well-described rat model. METHODS: Isolated segments of infrarenal aorta of 16 rats were perfused with porcine elastase. In the treated group, eight rats were given intravenous TNF-BP prior to elastase perfusion, at 48 hours and at 96 hours. In the control group, eight rats were given only intravenous vehicle at the same time intervals. Isolated segments of infrarenal aorta of an additional 16 rats were perfused with porcine elastase in a similar fashion. In the treated group, eight rats were given intraperitoneal IL-1RA prior to celiotomy and every eight hours. In the control group, eight rats were given only intraperitoneal vehicle at the same time intervals. On the sixth postoperative day, all rats underwent celiotomy and measurement of the infrarenal aortic diameter with a micrometer while the animal was alive. Aortic specimens were collected on day six for hematoxylin and eosin staining, trichrome staining, and gel polyacrylamide gel electrophoresis (PAGE) zymography. RESULTS: TNF-BP was completely able to block post elastase dilation, whereas IL-1Ra seemed to have no effect. Hematoxylin and eosin staining and trichrome staining revealed that animals treated with TNF-BP had less of an inflammatory response and preservation of the elastin and smooth muscles in the media of the aortic wall as compared with animals treated with IL-1RA or vehicle. Zymography was not able to detect significant protease activity in the aortic wall of any of the rats at six days. CONCLUSION: TNF-BP, but not IL-1RA, may inhibit the development of AAAs in this model.

Animals↗
PubMed1997

Upper extremity versus lower extremity deep venous thrombosis.

BACKGROUND: In contrast to lower extremity deep venous thrombosis (LEDVT), it is widely believed that upper extremity deep venous thrombosis (UEDVT) is associated with minimal morbidity or mortality. METHODS: In an attempt to compare the two disease processes with respect to pulmonary embolism and mortality, we have reviewed records and performed interviews of 430 patients with LEDVT and 52 patients with UEDVT presenting to our institution between January 1994 and June 1995. RESULTS: Pulmonary embolism was documented by ventilation/perfusion lung scan in 9 of 52 patients (17%) with UEDVT and 33 of 430 patients (8%) with LEDVT (P <0.05). Twenty-five of the UEDVT patients (48%) died within 6 months of the diagnosis of UEDVT. Conversely, 14 patients (13%) in the LEDVT group died within 6 months of the diagnosis of LEDVT (P <0.0002). CONCLUSION: Contrary to previous reports, this study suggests that UEDVT is associated with a higher morbidity and mortality as compared with LEDVT. These data show that UEDVT has been an underrecognized predictor of morbidity and mortality.

APACHE↗
PubMed1997

Upper extremity deep venous thrombosis and its impact on morbidity and mortality rates in a hospital-based population.

PURPOSE: Although much attention has been focused on lower extremity deep venous thrombosis (LEDVT), there is a relative paucity of data regarding the impact of upper extremity deep venous thrombosis (UEDVT) on morbidity and mortality rates. To increase our knowledge with the latter disease, we have reviewed our experience at our institution with 170 patients who had brachial, axillary, and subclavian vein thromboses. METHODS: Over the past 5 years, UEDVT was diagnosed in 170 patients by duplex scanning. The indications for duplex examination were either upper extremity swelling (95%) or as part of the workup for pulmonary embolism (5%). There were 103 women (61%) and 67 men (39%), with ages ranging from 9 to 101 years (mean, 68 +/- 17 years). The diagnosis was made in 152 patients (89%) while they were admitted to the hospital and in 18 patients (11%) in the outpatient clinic. Risk factors included presence of a central venous catheter or pacemaker in 110 patients (65%), malignancy in 63 patients (37%), concomitant LEDVT in 19 patients (11%), and history of LEDVT in 18 patients (11%). Fifty-six patients (33%) had multiple risk factors, whereas 36 patients (21%) had no obvious risk factor. RESULTS: The 1-month and 3-month mortality rates for the entire study group were 16% and 34%, respectively. Patients who had concomitant LEDVT, were 75 years of age or older, and were not treated with anticoagulation medication had a significantly higher 1-month mortality rate. Patients whose diagnoses were made in the outpatient setting were statistically younger and had a lower 3-month mortality rate when compared with the patients whose diagnoses were made as inpatients. Pulmonary embolism was documented by ventilation/perfusion scan in 12 patients (7%). Although no patient in the group in which UEDVT was diagnosed on an outpatient basis was documented to have a pulmonary embolism and 12 patients (8%) in the inpatient group had pulmonary emboli, this difference was not statistically significant. Anticoagulation medication did not totally prevent pulmonary embolism in this review. All patients were followed-up for between 0 to 49 months (mean, 13 +/- 1 months). No swelling of the affected arm was observed in 145 patients (94%); four patients complained of mild intermittent swelling (2%), and seven patients reported significant swelling (4%). CONCLUSIONS: Contrary to previous reports, these data suggest that UEDVT is associated with a low incidence of postthrombotic upper extremity swelling, but a significant incidence of pulmonary embolism and rate of mortality. This review suggests that UEDVT is at least as serious a disease entity as LEDVT and should be managed as aggressively as LEDVT.

APACHE↗
PubMed1996

The natural history of the external carotid artery after carotid endarterectomy: implications for management.

PURPOSE: Most surgeons perform some type of endarterectomy of the external carotid artery (ECA) routinely during standard carotid endarterectomy (CEA). This approach has been shown to result in a small percentage of ECA occlusions, the clinical significance of which remains poorly understood. We have modified our approach to the management of the ECA during standard CEA by averting any attempt at external CEA. To evaluate the natural history of the untreated ECA after CEA, we reviewed the preoperative, postoperative, and follow-up duplex scans obtained from 232 CEAs over the past 4 years. METHODS: Preoperative and postoperative carotid artery duplex examinations with specific evaluation of the extent of ECA stenosis were available for review on 114 CEAs performed between January 1991 and July 1994. All CEAs were performed for internal carotid artery stenosis greater than 75% as determined by duplex scanning, which was confirmed by either contrast arteriography or magnetic resonance angiography. RESULTS: Seventy-three (64.0%) procedures were performed for symptomatic lesions, whereas 41 (36.0%) were performed for asymptomatic stenosis. There were no perioperative strokes or transient ischemic attacks in this group, and there was one postoperative death (0.9%). Short- and intermediate-term follow-up demonstrated insignificant changes in ECA diameter after operation, with no cases of ECA occlusion and only five cases progressing to greater than 75% on the 1-year follow up duplex examination. CONCLUSION: We conclude from these data that averting external CEA during standard CEA does not result in significant progression of ECA stenosis or occlusion.

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PubMed1996

Intravenous intravascular ultrasound for arterial visualization: a feasibility study.

PURPOSE: The advent of endovascular grafting has created detailed imaging requirements for which intravascular ultrasound (IVUS) may be useful. Since intra-arterial IVUS imaging uses space within endovascular graft delivery systems and risks embolism, we investigated the use of intravenous IVUS imaging of arterial vasculature and endovascular grafts, a technique that appears not to have been previously described. METHODS: IVUS catheters with 12.5- and 20-MHz transducers were inserted through the common femoral artery and vein of mature sheep. Transcutaneous images were also obtained with a 5-MHz linear transducer. B-mode images of the aortoiliac arterial segments and diameter measurements were recorded from both access vessels using anatomic landmarks for site localization. To assess device visualization from the intravenous image source, studies were done in vessels containing previously placed endovascular stent-grafts. RESULTS: In this feasibility study, comparison among intravenous IVUS, arterial IVUS, and external ultrasound indicated equal diameter precision and ability to recognize arterial structures. Comparison of arterial diameter, whether obtained from an arterial, venous, or transcutaneous source, showed similar values. CONCLUSIONS: We conclude that it is probable for such techniques to be usefully applied to human aortoiliac arterial segments and that further investigation of arterial visualization from adjacent venous structures is warranted.

Animals↗
PubMed1993

Allograft vein bypass: is it an acceptable alternative for infrapopliteal revascularization?

PURPOSE: Autogenous vein bypass grafts to infrapopliteal outflow sites have patency and limb salvage rates significantly superior to those obtained with prosthetic grafts. However, when infrageniculate bypass is required for limb-threatening ischemia in the patient lacking suitable autogenous veins, nonautogenous reconstruction or primary amputation are the only other alternatives. METHODS: During a 2-year period we implanted 25 cryopreserved allograft saphenous vein bypass grafts in 24 patients (median age 76 years) with tissue necrosis (20 patients), rest pain (4 patients), or acute ischemia (1 patient); 16 patients were men and 8 were women. As many as six previous revascularizations were performed in 79%; two grafts extended to the infrageniculate popliteal artery; 23 grafts extended to a paramalleolar vessel. RESULTS: Secondary patency at 1 month was 87%, but only 36% at 1 year. Use of warfarin (Coumadin) failed to improve the patency rate (five of nine occlusions treated with Coumadin versus eight of 16 not treated with Coumadin). Only eight of 24 patients are alive with open grafts; nine patients have died. CONCLUSIONS: Unheralded occlusions more typical of prosthetic graft failure tempered the initial enthusiasm and effectiveness of vein allografts. All autogenous options must be exhausted to complete distal, secondary revascularization before resorting to nonautogenous conduits. Use of allograft veins must be viewed with continued skepticism.

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PubMed1986

The transition to "in situ" vein bypass grafts.

In situ saphenous vein bypass grafts were used to revascularize 109 lower extremities in 99 patients during 1984. Of those, 102 were single length grafts carried out in 53 males and 39 females with an average age of 69 and 75 years old, respectively. The expected associated risk factors were observed: smoking in 69 per cent, hypertension in 57 per cent, heart disease in 52 per cent and diabetes in 31 per cent of the patients. Grafts were performed for limb salvage in 71 patients, claudication in 30 and aneurysm in one. Single length grafts originated from the common (47), superficial (27), deep femoral (18) or popliteal (four) arteries or proximal Dacron (polyester) grafts (six); 93 per cent of the grafts were to an infrageniculate target site, while 44 per cent extended to an infrapopliteal artery and 7 per cent to the ankle. Operating time including completion angiography, which was done in every instance, was comparable to that with reversed vein grafts. The patency rate at one year was 96 per cent or 87 per cent when claudication or limb salvage was the indication for operation, and 92 per cent or 86 per cent when the distal anastomosis was to a popliteal or infrapopliteal artery. Limb salvage rates were 97 per cent at one month and 91 per cent at one year. All five amputations occurred in patients receiving infrapopliteal grafts for gangrene. The survival rate was 97 per cent at one month and 85 per cent at one year.

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