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Introduction: Completion imaging following carotid endarterectomy (CEA) remains controversial. We present our experience performing routine completion arteriography (CA). Methods: A retrospective review of our prospectively maintained institutional database was performed for patients undergoing isolated CEA. Results: 1439 isolated CEAs with CA were performed on 1297 patients. CEA was for asymptomatic lesions in 70% (1003) of cases. There were no complications related to arteriography. An abnormal arteriogram documented significant abnormalities in the internal carotid artery (ICA) and prompted revision in 1.7% (24/1439) of cases: 20 unsatisfactory distal endpoints of the endarterectomy (12 residual stenoses, 7 intimal flaps, and 1 dissection), 3 kinks or stenoses within the body of the patch, and 1 thrombus. Of the 20 distal endpoint lesions, stent deployment was used in 17 cases and patch revision in 3 cases. The other 4 cases were treated by patch angioplasty (3) or thrombectomy (1). None suffered a perioperative stroke. The overall 30-day stroke, death, and combined stroke/death rate for the 1439 patients in our series was 1.5% (22),.5% (7), and 1.9% (27), respectively. The combined stroke/death rate for asymptomatic lesions was 1.1% (11/1003) and for symptomatic lesions was 2.5% (11/436). Of the 22 strokes in the entire series (all with normal CA), 15 were non-hemorrhagic strokes ipsilateral to the CEA; 14 were confirmed to have widely patent endarterectomy sites by CT-A (13) or re-exploration and repeat arteriography (1). The occluded site was re-explored and underwent thrombectomy, but no technical problems were identified. The remaining strokes were hemorrhagic (4 reperfusion syndrome and 1 surgical site bleeding) or contralateral to the CEA (2). Conclusion: Although not all patients in this series who underwent intraoperative revision due to abnormal CA might have suffered a stroke, performing this simple and safe study may have halved our overall perioperative stroke rate from 3.2% to 1.5%. [ABSTRACT FROM AUTHOR]

Objectives: Pancreaticoduodenal artery aneurysms (PDAAs) are rare and have a high propensity for rupture. Historically, management of PDAAs included surgical reconstruction but has evolved with advances in endovascular therapy. We report our experience with management of PDAAs during the last 30 years. Methods: We retrospectively reviewed our prospectively maintained registry between January 1, 1992 – March 30, 2020. Results: We identified 8 patients with PDAAs: 4 with associated celiac artery occlusive disease and 4 without identifiable etiologies. Four patients were treated with surgical resection of the PDAAs: 2 intact aneurysms underwent concomitant revascularization (superior mesenteric artery-to-hepatic artery Dacron bypass; supra celiac aorta-to-hepatic artery Dacron bypass) and 2 (1 intact, 1 rupture) underwent ligation alone. Four patients were treated with coil embolization of the PDAA: 2 with concomitant stent-graft exclusion of the aneurysm (1 non-rupture, 1 rupture) and 2 without adjunctive measures (intact). There were no deaths nor any significant procedure-related morbidity. Conclusion: Our large single-center experience shows that PDAAs can be successfully treated by open or endovascular intervention with selective revascularization. [ABSTRACT FROM AUTHOR]

Objective: The Society for Vascular Surgery stated there are a lack of studies describing long-term surveillance for aortobifemoral (AoBF) bypasses. Our goal was to investigate the value of DU studies as a surveillance tool for AoBF bypasses. Methods: We retrospectively identified patients in our prospectively maintained database who underwent AoBF bypasses between 1995-2018. Surveillance was performed routinely with DU post-operatively, every 6 months for 1 year, and then annually. We considered "abnormal" DU findings to include peri-graft fluid, pseudoaneurysm or, peak systolic velocities (PSVs) > 350 cm/sec or PSV ratio > 3.5 anywhere from the proximal aortic to distal femoral anastomosis. If abnormalities were identified patients underwent intervention or shorter surveillance intervals. Results: Of 153 AoBF bypasses, 60 patients with 120 graft limbs fulfilled our post-operative surveillance protocol with a mean follow-up of 4.0 years (0.5-24 years). "Normal" DU surveillance studies were documented throughout follow-up in 112 (93%) limbs. Of these, 2 (1.7%) developed acute limb occlusion. Eight (6.7%) limbs had "abnormal" DU findings: 5 failing grafts with focal elevated PSVs, 2 with peri-graft fluid leading to a diagnosis of an infected graft, and 1 with a pseudoaneurysm (PSA). Contrast arteriography or CT-angiography confirmed > 75% diameter stenosis, fluid or PSA in all 8 limbs. Graft revision (5 endovascular, 2 surgical) was performed in 7 of the 8 limbs initially or after 2 successive "abnormal" DU studies within 6 weeks of each other; 1 patient refused intervention. Without surveillance, urgent or emergent treatment might have proved necessary in 7.5% (7 + 2 = 9/120) of cases instead of only 1.7% (2/120) of cases. Conclusion: Vascular surgeons should adopt DU as a useful surveillance tool to identify AoBF bypasses that are failing or have other problems not identified clinically. Persistence of "abnormal" DU findings should prompt operative or endovascular intervention. [ABSTRACT FROM AUTHOR]

Anomalous connections between the anterior and posterior cranial circulation are rare embryologic entities. A persistent hypoglossal artery has a reported incidence of 0.03% to 0.09% and has been linked to intracranial aneurysms, atherosclerosis, and posterior circulation ischemia. Identification of this anomaly is essential prior to carotid artery revascularization given the technical challenges and added risks with intervention. We report a case of an 80-year-old female with progression of carotid stenosis in the setting of a persistent hypoglossal artery. We provide a review of the literature and discuss the technical challenges of carotid revascularization in this patient. [ABSTRACT FROM AUTHOR]

Objective: Traditionally, vascular surgery fellows (VSFs) have learned to perform peripheral arterial endovascular procedures in a hospital setting. Many vascular surgeons currently perform these procedures in an "outpatient" non-hospital-based setting. Loss of these cases from the hospital setting may impact vascular surgery fellowship endovascular volume. We assessed the safety of first-year VSFs performing peripheral endovascular procedures under the supervision of vascular surgery attending surgeons in a non-hospital-based facility. Methods: Between January 1, 2012, and December 31, 2016, 166 patients underwent 193 endovascular procedures in a non-hospital-based ambulatory facility: 136 interventions (65 femoral, 40 iliac, 13 popliteal, and 9 infrapopliteal arteries) and 31 diagnostic arteriograms for claudication (57.8%; 85), rest pain (11.6%; 17), tissue loss (12.9%; 19), and failing grafts (17.7%; 26). Interventions included balloon angioplasty alone in 8.8% (12/136) of cases, stents in 16.9% (23/136), covered stents in 14% (19/136), atherectomy in 60.3% (82/136), and mechanical thrombolysis in 0.7% (1/136). Results: First-year VSFs performed an increasing percentage of these procedures during this interval: academic year 2012 to 2013 = 0% (0/49), 2013 to 2014 = 31% (17/54), 2014 to 2015 = 93% (56/60), and 2015 to 2016 = 82% (57/70). All but 5 (3%) patients having 167 procedures were discharged home after 2 to 6 hours of bed rest without any 30-day adverse outcomes. Four patients were immediately transferred to our hospital after the intervention: 2 for respiratory issues (hypoxia), 1 for groin hematoma (observation only), and 1 for arterial occlusion (required tibial stent not available at outpatient center). One patient returned to our hospital with rest pain due to treatment site occlusion the following day. Conclusion: Our results demonstrate that complex peripheral arterial endovascular procedures can be performed safely by first-year VSFs under vascular attending supervision in an outpatient, non-hospital-based setting. [ABSTRACT FROM AUTHOR]

Nutcracker syndrome is a rare entity in which compression of the left renal vein (LRV), usually by the overlying superior mesenteric artery (SMA), results in renal venous congestion and reflux in the left ovarian vein (LOV). Patients may present with hematuria, left flank pain, dyspareunia, and vaginal or abdominal wall varicose veins. We report a patient with nutcracker syndrome who presented atypically with left flank pain that was exacerbated in the postprandial state. We hypothesize that the physiologic dilation of the SMA after oral intake caused increased LRV compression at that site and augmented lateral LRV distention. The patient had no evidence of SMA syndrome or chronic mesenteric insufficiency. Her symptoms resolved after we performed an LOV to inferior vena cava transposition. [ABSTRACT FROM AUTHOR]

Objective: We analyzed our results with percutaneous rotational atherectomy catheters and specifically examined whether they were more likely to be associated with a successful outcome when used to treat smaller diameter vessels such as infrapopliteal (IP) arteries compared to larger diameter femoropopliteal (FP) arteries and infrainguinal arterial autogenous vein grafts (GRAFTS). Material and Methods: Between January 1, 2005, and December 31, 2006, athrectomies were performed on 32 patients for claudication (14), gangrene (9), rest pain (4), and failing GRAFTS (5). Treated vessels included 14 superficial femoral, 1 popliteal, 5 anterior tibial, 4 posterior tibial, and 3 peroneal arteries along with 5 failingGRAFTS. All procedures were performed by vascular surgeons in an endovascular operating suite using a mobile C-arm. Results for larger diameter vessels including FP arteries and GRAFTS were combined (FP + BYPASSES) and compared to results of IP artery lesions. Follow-up averaged 10 weeks (range, 0.5-34 weeks). Results: Length of treated lesions averaged 4.2 cm (range, 1-15 cm) for FP + GRAFT lesions (9 occlusions, 11 stenoses) versus 1.8 cm (1-4 cm) for IP lesions (6 occlusions, 6 stenoses; P ¼ ns). Procedural success rate based on postoperative segmental pressures, pulse volume recordings, and duplex ultrasound was 70% (14/20) for FP + GRAFTS versus 83% (10/12) for IP lesions (P ¼ .03). Need for concomitant adjunctive balloon angioplasty to treat residual stenosis tended to be higher for FP + GRAFT lesions (40% [8/20]) compared to IP lesions (25% [3/12]; P ¼ ns). During follow-up, 25% (5/20) of FP + GRAFTS lesions required reintervention (3 balloon angioplasties, 1 thrombectomy, 1 GRAFT pseudoaneurysm) versus none for the IP lesions (P ¼ .03). Limb salvage rates were 90% (18/20) for FP + GRAFT lesions versus 100% (12/12) for IP lesions during this short follow-up. Conclusions: These preliminary results suggest that short segment IP arterial stenoses and occlusions can be successfully treated with atherectomy catheters with a lower rate of reintervention during short-term follow-up, less need for concomitant adjunctive balloon angioplasty and a lower complication rate compared to FP + graft lesions. [ABSTRACT FROM AUTHOR]

Introduction: Surgical revision of failing peripheral arterial bypass grafts has generally been shown to provide superior patency rates compared to balloon angioplasty. We analyzed whether balloon angioplasty, specifically of peri-anastomotic stenoses (PAS), provided acceptable patency rates, because surgery for these lesions is more difficult and is likely associated with higher complication rates compared to surgical revision of stenoses in the body of a graft. Methods: This is a retrospective review of PAS balloon angioplasties performed at a single institution between January 1, 1999, and September 1, 2005. We report ''primary site patency'' as a stenosis treated by balloon angioplasty, ''revised primary site patency'' as a stenosis treated by repeat balloon angioplasty, and ''secondary site patency'' as an angioplastied stenosis treated surgically or when the graft thrombosed and was revised surgically. All procedures were performed in an endovascular operating room based on duplex scan findings suggesting a significant stenosis. Results: 48 PAS in 33 autologous vein and 15 prosthetic grafts were treated by balloon angioplasty in 42 patients. Mean follow-up was 12 months (range, 1-49 months). Interventions were performed on 22 femoropopliteal grafts (11 proximal, 11 distal), 20 femorotibial grafts (5 proximal, 15 distal), 2 axillofemoral grafts (2 proximal anastomoses), 2 popliteal-pedal grafts (1 proximal, 1 distal), and 1 common iliac-femoral graft (proximal). Life-table analysis revealed 2-year primary, assisted primary, and secondary patency rates of 38%, 58%, and 84%, respectively. No major complications occurred with any endovascular intervention. Conclusion: Balloon angioplasty of PAS resulted in acceptable 2-year assisted primary patency rate of almost 60%. Endovascular intervention avoided repeat incisions in scarred groins, higher rates of nerve injury and infection, significant blood loss, and longer length of hospital stays. We recommend that balloon angioplasty of PAS be attempted before resorting to surgical intervention, especially in cases of hostile anastomotic wounds. [ABSTRACT FROM AUTHOR]

Intraoperative completion studies of the internal carotid artery following carotid endarterectomy are recommended to ensure technical perfection of the repair. Transit time ultrasound flowmeter does not require trained technicians, requires less time than other completion studies such as duplex ultrasonography and contrast arteriography, and is noninvasive. Flowmetry was compared with duplex ultrasonography and contrast arteriography to determine if the relatively simpler flowmetry could replace these two more widely accepted completion studies in the intraoperative assessment of carotid endarterectomy. Comparative intraoperative assessment was performed in 116 carotid endarterectomies using all three techniques between December 1, 2000 and November 30, 2003. Eversion endarterectomy was performed in 51 cases and standard endarterectomy with prosthetic patching in 65 cases. Patients underwent completion flowmetry, duplex ultrasonography, and contrast arteriography studies of the exposed arteries, which were performed by vascular fellows or senior surgical residents under direct supervision of board-certified vascular surgeons. Duplex ultrasonography surveillance was performed 1 and 6 months postoperatively and annually thereafter. Mean follow-up was 18 months (range, 6–42 months). The combined ipsilateral stroke and death rate was 0%. The mean internal carotid artery flow using flowmetry was 249 mL/min (range, 60–750 mL/min). Five (4.3%) patients had flow < 100 mL/min as measured with flowmetry, but completion contrast arteriography and duplex ultrasonography were normal and none of the arteries were re-explored. One carotid endarterectomy was re-explored based on completion duplex ultrasonography that showed markedly elevated internal carotid artery peak systolic velocity (>500 cm/sec); however, exploration was normal and completion flowmetry and contrast arteriography were normal. Duplex ultrasonography studies revealed internal carotid artery peak systolic velocities > 150 cm/sec in 15 patients, but flowmetry and contrast arteriography were normal in all 15 cases and none of the arteries were re-explored. There was no correlation between flow rates measured using flowmetry and peak systolic velocities measured using duplex ultrasonography One abnormal contrast arteriogram showed an intimal flap that was revised, but duplex ultrasonography and flowmetry were normal. Severe recurrent internal carotid artery stenosis developed in 2 patients at 6 and 9 months, but all 3 completion intraoperative studies at the time of the original operation were normal. Based on these results, wide variability in flowmetry values limits its potential usefulness to detect non-flow-limiting lesions and replace contrast arteriography or duplex ultrasonography as an intraoperative carotid endarterectomy completion study. Duplex ultrasonography was also of limited to no value, whereas contrast arteriography rarely documented a lesion that required repair. [ABSTRACT FROM AUTHOR]

Surgical management of juxtarenal aortic (JR-Ao) aneurysms and occlusive disease may include supraceliac aortic clamping, a retroperitoneal approach, or medial visceral rotation. The authors report their results using preferential direct suprarenal aortic clamping via a midline transperitoneal incision. Between July 1, 1992, and July 31, 2001, they treated 58 patients with JR-Ao disease (44 aneurysmal, 14 occlusive) via a midline incision without medial visceral rotation. Preferential suprarenal aortic clamping was used in 53 cases (42 proximal to both renal arteries, 11 proximal to the left renal artery only) and supraceliac or supramesenteric clamping in S cases when there was insufficient space for an aortic clamp between the superior mesenteric artery and renal arteries. This strategy avoided mesenteric ischemia associated with supraceliac clamping in the majority of cases and afforded better exposure of the right renal artery than obtainable with a left retroperitoneal approach or medial visceral rotation. Eleven patients underwent concomitant renal revascularization. Critical adjuncts included the following: (1) selective left renal vein (LRV) division if the vein stump pressure was <35 mm Hg (suggesting sufficient renal venous collaterals existed), (2) bilateral renal artery occlusion during aortic clamping to prevent thromboembolism, (3) flushing of aortic debris before restoring renal perfusion, and (4) routine administration of perioperative intravenous mannitol and renal-dose dopamine. Patients with type IV thoracoabdominal aneurysms, ruptured aneurysms, or JR-Ao disease approached via a retroperitoneal incision (severely obese patients, re-do aortic surgery) were excluded. No patients died or required dialysis during their hospital stay. The LRV was divided in 12 (21%) cases and reanastomosed in 2 cases (elevated stump pressures). The average suprarenal clamp time was 26 minutes (range, 10-60). Postoperative serum creatinine remained > 0.5 ng/dL above baseline in 3 (5%) patients. These results support suprarenal aortic clamping with a midline transperitoneal incision as the optimal strategy for treating juxtarenal aortic aneurysms and occlusive disease. The authors believe that selective left renal vein division enhances juxtarenal aortic exposure, and routine administration of renal protective agents, along with occlusion of both renal arteries during suprarenal aortic clamping, are critical adjuncts in performing these operations. [ABSTRACT FROM AUTHOR]

Endovascular abdominal aortic aneurysm repair (EVAR) has been predominantly accomplished by teams of multidisciplinary interventionalists, frequently under the primary direction of cardiologists and radiologists. The purpose of this paper was to examine the feasibility and safety of an initial experience of EVARs performed by vascular surgeons at a single institution without other interventionalists. The authors reviewed the first 50 EVARs performed solely by vascular surgeons at our hospital, which we believed represented a fair and sizable enough learning curve for this new procedure. The operations were performed in an endovascular operating room and the surgeons had prior endovascular experience. The EVAR protocol included preoperative abdominal computed tomography (CT) scans and aortograms, same-day admissions, epidural anesthesia, transfer to the ward the day of surgery, and discharge the first postoperative day. CT scans were performed on postoperative day 1 and then annually, unless duplex ultrasound (DU) suggested an endoleak. DU was performed 1 week postoperatively, every 3 months for the first year, and then every 6 months thereafter. Of the first 23 patients, 3 required immediate conversion to open repair because of device malfunction (all in a Phase Ill FDA trial) and 1 underwent conversion 3 weeks after initial graft placement during treatment of a failing endograft limb as diagnosed by duplex ultrasonography. None of the next 27 cases required conversion. In 2 (4%) patients, graft limb occlusions occurred postoperatively and were treated with femorofemoral crossover grafts. There were 5 (10%) endoleaks: 2 were treated endovascularly, I closed spontaneously, and 2 were followed. Several advanced adjunctive endovascular procedures were performed concomitantly during EVAR including internal iliac artery coil embolization using aortic crossover catheters in 16% (8/50) of patients, proximal or distal extension cuff placement in 16% (8/50), and graft limb stenting in 50% (25/50). The average length of stay for patients who underwent uncomplicated aortic stent grafts was 1.9 days (range, 1-4 days) compared to 2.3 days for all patients (range 1-13 days). In no case were other interventionalists necessary for intraoperative assistance. These results of EVAR performed solely by vascular surgeons are comparable to reports by multidisciplinary teams and support the premise that vascular surgeons with endovascular skills have the knowledge and capability to begin performing EVAR independently of other specialists. [ABSTRACT FROM AUTHOR]

The management of infected prosthetic grafts is one of the most challenging problems facing vascular surgeons. High mortality and morbidity rates with traditional treatment have led many surgeons to consider different and novel strategies. Diagnosis is usually straightforward, but occasionally is unclear even after extensive clinical and radiologic investigations. Although routine total graft excision for all infected aortic grafts is still favored by some vascular surgeons, most favor only partial graft excision if only the distal limb of the graft is involved. Placement of in situ autologous vein or cryopreserved grafts have gained popularity, and investigations are continuing regarding the use of in situ antibiotic and silver-coated prosthetic grafts. In this article the authors review the incidence and etiology of aortic graft infections, methods to prevent these complications, the diagnosis of infected aortic grafts, and lastly the management of these complicated cases, including total graft excision and partial and complete graft preservation. [ABSTRACT FROM AUTHOR]

Presents a study that analyzed the safety and cost effectiveness of endovascular procedures for patients undergoing outpatient interventions combined with open arterial surgery. Factors that contribute to the need for hospital admission and observation; Correlation between overnight stay and longer operative times; Changes in admission rates for patients; Complications of the surgery.

Examines the replacement of general anesthesia by cervical block anesthesia for carotid endarterectomy. Intolerance of patient to cervical block anesthesia; Occurrence of neurologic changes when administering cervical block anesthesia; Presence of ipsilateral stroke history in both anesthetic methods.

Clinical Experience Level III training in vascular medicine should provide the knowledge and skills to function as a vascular specialist, including the ability to interpret patients' clinical presentation, plan diagnostic testing, apply clinical and laboratory information, and develop appropriate management plans for patients across the entire range of vascular diseases. For patients with atherosclerotic cerebrovascular disease, trainees should define and apply appropriate risk stratification and medical therapies to reduce risk of stroke, including managing the most common risk factors for development and progression of cerebrovascular disease (e.g., smoking, diabetes, hypertension, hypercholesterolemia). They should know the diagnostic and management strategies relevant to specific patient populations, such as pregnant women, patients with cancer, patients with severe obesity, and patients with chronic kidney disease. They should be able to initiate compression therapy, refer to a physical therapist specialized in manual lymphatic therapy and multimodal lymphedema therapy, and determine if a patient would benefit from advanced therapies such as compression pumps or referral for surgery. [Extracted from the article]

Aortic graft infections are a rare occurrence, most commonly secondary to gram-positive organisms (Staphylococcus and Streptococcus species). We present 2 cases of thoracic aortic graft infections secondary to anaerobic bacteria, Propionibacterium species. The first case, a 40-year-old male, was found to have an anastomotic aneurysm at the distal anastomosis of a previous thoracoabdominal aneurysm repair. During the open repair of his anastomotic aneurysm, the original graft was not incorporated and cultures later speciated Propionibacterium acnes. The second case is a 44-year-old male with a history of abdominal aortic coarctation that was repaired with a thoracic aorta to aortic bifurcation graft as a child who presented with flank pain and was found on imaging to have fluid around his bypass graft. His operating room (OR) cultures also grew out Propionibacterium species. Both patients were treated with graft excision, revascularization, and long-term antibiotics. Anaerobic bacteria are a rare cause of aortic graft infections. Upon review of the literature, these are the first 2 cases of thoracic aortic graft infections secondary to Propionibacterium species. The cultures for both patients took almost a week to speciate, highlighting the importance of following cultures long term. Anaerobic bacteria should be recognized as a cause of latent graft infections. [ABSTRACT FROM AUTHOR]

Objective: Stent grafts, also known as covered stents, have become an increasingly acceptable treatment for popliteal artery aneurysms. However, endovascular exclusion confers lower primary patency compared to traditional open bypass and exclusion. The purpose of this study was to evaluate whether duplex ultrasonography (DU) can reliably diagnose failing stent grafts placed for popliteal artery aneurysms prior to occlusion. Methods: Between June 5, 2007, and March 11, 2014, 21 stent grafts (Viabahn; Gore, Flagstaff, Arizona) were placed in 19 patients for popliteal artery aneurysms. All patients had at least 1 follow-up duplex scan postoperatively. Mean follow-up was 28.9 months (9-93 months). Postoperative DU surveillance was performed in our Intersocietal Accreditation Commission noninvasive vascular laboratory at 1 week postprocedure and every 6 months thereafter. Duplex ultrasonography measured peak systolic velocities (PSVs) and ratio of adjacent PSVs (Vr) every 5 cm within the stent graft and adjacent arteries. Results: We retrospectively classified the following factors as “abnormal DU findings”: focal PSV > 300 cm/s, uniform PSVs < 50 cm/s throughout the graft, and Vr > 3.0. These DU criteria were derived from laboratory-specific data that we previously published on failing stent grafts placed for lower extremity occlusive disease. Four of the 21 stent grafts presented with symptomatic graft thrombosis within 6 months of a normal DU. Three of these 4 patients presented with rest pain and underwent thrombectomy (2) or vein bypass (1), and 1 elected for nonintervention for claudication. Conclusion: Our results suggest that surveillance DU using criteria established for grafts placed for occlusive disease may not be useful for predicting stent graft failure in popliteal artery aneurysms. [ABSTRACT FROM AUTHOR]

Phlegmasia cerulea dolens (PCD) is a rare form of venous gangrene that arises secondary to occlusion of venous outflow from a limb. Classically described in the lower extremity, it is rare in the upper extremity. We present a case report of upper extremity PCD and a systematic review with data analysis of 37 cases of PCD published in PubMed. Our analysis showed that concurrent lower extremity PCD was a statistically significant marker for worse outcomes in this patient population. [ABSTRACT FROM AUTHOR]

Presents a study that compared the effectiveness of balloon angioplasty with stent replacement to surgical patch angioplasty for thrombosed upper arm hemodialysis grafts with stenotic lesions at the venous anastomosis. Analysis of the primary and secondary patency for both techniques; Comparison on the patency of the two techniques using Kaplan-Meier survival analysis; Assessment of the complication rates of the two techniques.