Femoral Bypass Graft Research Articles

Arterial Allograft Allows In-line Reconstruction of Prosthetic Graft Infection with Low Recurrence Rate and Mortality

Surgical management of infected prosthetic vascular grafts is associated with a significant risk of recurrent infection, limb loss, and mortality. Treatment options include graft excision with extra-anatomic bypass and in-line repair with prosthetic graft, vein, or artery. We hypothesized that in-line reconstruction using cryopreserved arterial allografts would be associated with a lower recurrent infection rate, limb loss, and mortality than other alternatives. We reviewed all cases where adults underwent surgical management of infected prosthetic aortic, iliac, or femoral bypass grafts with cryopreserved arterial allograft at our medical center from 2001 to 2008. Cryopreserved arterial allografts were used in 21 patients. There were nearly equal number of men (n = 11, 52%) and women (n = 10, 48%). The median age was 63 years and median time since cryoartery repair was 4 years. There have been no deaths in the follow-up period. Complications (19%) included colon perforation (n = 1), lower extremity compartment syndrome (n = 1), limb ischemia (n = 1), and reinfection with pseudoaneurysm and subsequent limb amputation (n = 1). These positive findings of low morbidity and absence of mortality in high risk patients have resulted in a shift at our institution to the preferential use of cryopreserved arterial allograft with in-line reconstruction for infected prosthetic grafts.

Carotid artery stenting via a femoral bypass graft: technical note

Background We described a case of endoluminal stent placement for a cervical internal carotid artery stenosis in which access was obtained via the femoral bypass graft. Case Description A 70-year-old man with known disease of the carotid, peripheral, and coronary arteries as well as congestive heart failure presented for endoluminal revascularization of a severe right internal carotid artery stenosis. Transradial access was complicated by the left subclavian artery occlusion and hypercalcified aortic arch. Bilateral femoral artery was replaced with bypass graft because of atherosclerosis obliterans. An alternative approach was attempted via the exposed left femoral bypass graft. The left inguinal region was incised, and the left common femoral-popliteal bypass graft was exposed. After placement of a purse string suture at the puncture site, the guiding sheath was introduced into the graft and positioned into the right common carotid artery. Stenting was successfully performed, and the suture was tied after withdrawing the sheath. Conclusions This novel approach should be considered for endovascular procedures for which access to the carotid artery is limited.

Long-Term Outcome following Stent Reconstruction of the Aortic Bifurcation and the Role of Geometric Determinants

We assessed the long-term patency of kissing stent reconstruction of the aortoiliac bifurcation and identified variables that may influence it. We retrospectively reviewed our experience with stent-reconstruction procedures of the aortoiliac bifurcation from January 1998 through June 2005. The impact of demographic variables, vascular risk factors, disease location and characteristics, stent material and design, and stenting configuration on stent patency was assessed using univariate and multivariate analysis. In particular, we evaluated the effect of geometric mismatch between the protruding segment of the stents and the distal aortic lumen. Sixty-six patients underwent aortobi-iliac stent reconstruction. Indications were bifurcation or bilateral proximal iliac disease in 52 patients and unilateral ostial disease requiring contralateral protection in 14 patients. Limited disease (TASC A and B) was present in 40 limbs in 19 patients; extensive/diffuse disease (TASC C and D) was present in 78 limbs in 47 patients. Complete occlusions were present in 37 limbs in 28 patients (bilateral in nine patients). Self-expanding stents were used in 56 procedures and balloon-expandable stents in 10. Crossing configuration was used in 43 procedures, while abutting configuration was used in 23 procedures. Technical success was achieved in 62 patients (94%), with all four failures due to inability to cross a chronically occluded limb. Three of these patients underwent aortomono-iliac stenting with a crossover femoral-femoral bypass graft, with the remaining one opting for no further interventions. Median combined follow-up was 37 +/- 27 months (range 0-102). Hemodynamically significant restenosis developed in nine patients (14%). The management of restenosis was endovascular in eight patients and was successful in all (balloon dilation in four, restenting in three, thrombolysis and stenting in one) and operative in one patient who developed aortic occlusion and underwent aortobifemoral grafting. Survival table analysis showed primary and assisted patency rates at 4 years of 81% and 94%, respectively. The mortality rate during follow-up was 19 (cardiac cause in eight, pulmonary cause in three, and malignancy in five). Univariate analysis showed radial mismatch (aortic lumen dead space around the protruding segment of the stents), female gender, prior occlusion, and residual stenosis to be significant predictors of restenosis. Multivariate logistic regression analysis showed radial mismatch to be the only significant determinant of restenosis, although the statistical power of the model was limited by the small number of restenoses. Stent reconstruction of the aortoiliac bifurcation for occlusive disease is effective and durable, even with complex aortoiliac disease and long segment occlusions. Most restenoses are amenable to endovascular treatment, with excellent long-term assisted patency. Geometric variables related to individual aortic anatomy and disease pattern (patient-dependent) and stenting configuration (operator-dependent) may have an impact on long-term patency.

Numerical study of hemodynamics comparison between small and large femoral bypass grafts

AbstractThe geometry factors have prominent impacts on the flow patterns of bypass graft. In order to clarify the influence of graft diameter on the hemodynamics of femoral bypass graft, the pulsatile blood flows in three bypassing models with different graft diameters were simulated with finite‐element method. The temporal–spatial distributions of flow patterns, pressure drops, and wall shear stresses were depicted and compared. The results indicated that femoral artery bypassed with a large graft demonstrates relatively better and more profitable hemodynamic phenomena with large longitudinal velocity, uniform wall shear stress, and small wall shear stress gradient. The large model may be effective in decreasing the probability of the initiation and development of postoperative intimal hyperplasia and restenosis. Copyright © 2007 John Wiley & Sons, Ltd.

Wall thickening and its relation to local haemodynamic parameters in femoral bypass grafts

Wall thickening and its relation to local haemodynamic parameters in femoral bypass grafts

Aorto-iliac reconstructions for intermittent claudication.

Over a 12-year period, 290 aortofemoral reconstructions were performed for intermittent claudication involving 449 legs in 262 patients. The accumulative patency rate in surviving patients was 79 per cent at 5 years. The patency rate was significantly better in patients who stopped smoking after operation, and in men compared with women. Dacron grafts were significantly more successful than endarterectomy in men. If there was no associated superficial femoral artery occlusion, endarterectomy and Dacron bypass grafts were equally successful, but Dacron bypass grafts were significantly superior to endarterectomy if the superficial femoral artery was severely stenosed or occluded. The success rates for improving the patients' intermittent claudication were 90 per cent at 3 months and 72 per cent at 3 years. The success rate at 3 years was 80 per cent if the superficial femoral artery was patent but only 62 per cent if the superficial femoral artery was severely stenosed or occluded. Mortality and morbidity rates fell markedly in the last 6 years of the study.

Cystic adventitial disease: a case report and literature review

Cystic adventitial disease (CAD) is a rare non-atherosclerotic cause of peripheral vascular disease (PVD). We describe a 54-year-old man who presented with calf claudication and catheter angiography showed the typical scallop appearances of CAD. Surgery involved resection of the diseased segment with a femoral popliteal venous bypass graft. A literature review revealed the different theories for pathogenesis, the investigation of choice being catheter angiography and the treatment excision with bypass grafting.

A novel approach for lower limb ulcers – KerrabootR

Introduction and social history This case study presents the usc of a novel wound management product used to treat pressure ulcers on a diabetic patient's foot. Mrs H is an 81-year-old married lady who, prior to April 2004, had been relatively independent. She lived on her own, was self-caring and mobilised short distances with the aid of a zimmer frame. Mrs H had no official home help but her daughter would visit her three times a week to help as necessary. Mr H was cared for in a nursing home. In April 2004 Mrs H was admitted to her local hospital for a total of 10 weeks with recurrent chest infections. Shortly after this she was readmitted with leg oedema, confusion and decreased mobility. After several weeks she was transferred for respite care but readmitted within days with congestive cardiac failure. (This cycle of recurrent admiSSions and respite continued for a total of six months). Previous medical history includes a left femoral popliteal bypass graft in 1998 that was known to have occluded by 2002, a myocardial infarction (2004), congestive cardiac failure, atrial fibrillation and type 1 diabetes mellitus.

Wall shear stresses in small and large two-way bypass grafts

Wall shear stress, as one of the most important hemodynamic parameters of the cardiovascular system, has been studied extensively in the numerical and experimental approaches to blood flow in various arteries. In order to clarify the influence of graft diameter on the wall shear stress in a femoral two-way bypass graft, the pulsatile blood flows in two models were simulated with the finite element method. Both models were constructed with different diameters of grafts. The main geometric structure and the boundary conditions were identical for both models. The emphasis was on the comparison analysis of wall shear stresses in the vicinity of the distal anastomosis. The temporal–spatial distributions of wall shear stresses, wall shear stress gradients, and oscillating shear index were analyzed and compared. The present study indicated that femoral artery bypassed with a large graft demonstrated relatively uniform wall shear stresses and small wall shear stress gradients, whereas it does not have advantages in the oscillating shear index. The large model exhibits better and more regular hemodynamic phenomena and may be effective in decreasing the probability of the initiation and development of postoperative intimal hyperplasia and restenosis. Thus, appropriately large grafts are applicable in the clinical practice of femoral two-way bypass operation. More detailed studies are necessary on this problem for the purpose of increasing the success rates of the femoral bypass grafts.

Replacement of in situ saphenous venous aneurysms with arterial autografts

Background Aneurysm formation in arterialized autologous saphenous veins is an unusual complication of in situ femoral popliteal bypass procedures. Methods In a personal series of 207 in situ saphenous femoral popliteal bypass operations, three nonanastomatic venous aneurysms occurred. All three venous aneurysms occurred in male patients who had no adequate autologous vein available as an interposition graft. The use of eversion endarterectomized superficial femoral artery is reported as a substitute interposition graft with long-term results. Results In the 3 male patients in this series, nonanastomatic aneurysms developed in their in situ saphenous femoral popliteal bypass grafts. The venous aneurysms developed between 5 and 8 years after the original surgical procedure. No adequate vein was available as a replacement for the excised venous aneurysm. Prosthetic conduit was not used owing to the remote possibility of a subclinical infection. A segment of eversion thromboendarectomized superficial femoral artery removed from the same leg was used as a replacement interposition graft in each patient. The in situ venous graft with the autologous interposition thromboendarterectomized superficial femoral artery remained patent until each patient's death 4 to 7 years after the venous aneurysm replacement. Conclusions A short segment of endarectomized superficial femoral artery has been found to be a novel solution for the treatment of isolated saphenous vein graft aneurysms when no suitable vein is available. These patients should be maintained on lifelong aspirin therapy owing to the thrombogenic potential of endarectomized artery.

In situ Femoral to Popliteal Bypass Graft Using Superficial Femoral Vein to Popliteal Vein

During the evolution of vascular surgery as a specialty, many conduits have been used to revascularize the lower extremities. Superficial veins and prosthetic materials make up the majority of materials used to bypass diseased segments of native artery. The deep veins of the thigh have also been reported as alternatives for arterial bypass. However, the use of the in situ superficial femoral and popliteal vein bypass has not been reported to our knowledge in current literature. We report a 79-year-old white female with lower extremity rest pain who underwent an in situ femoral popliteal bypass graft for limb salvage.

Transbrachial thrombolysis, PTA and stenting in the lower extremities.

We present an analysis of 37 interventions in the arteries of the lower limbs via a transbrachial arterial approach. Twenty-six patients (42-79 years) underwent 37 interventional procedures in the lower extremities (iliac n = 6, iliac + femoro-popliteal n = 1, femoro-popliteal n = 30) with a vascular approach via the brachial artery (33 left sided, 4 right sided, introducer sheath 4-7 F). The transbrachial approach was chosen to avoid puncture of femoral bypass graft material. Technical success could be achieved in 11/13 thrombolyses, 8/9 PTAs, 7/10 combinations of thrombolysis and percutaneous transluminar angioplasty (PTA) and in the placement of two stents. One patient suffered from periprocedural severe re-thrombosis due to insufficient anticoagulation during fibrinolysis, and twice thrombolysis was incomplete. One puncture-related false aneurysm of the brachial artery had to be corrected surgically. One transient ischemic attack (TIA) and four minor complications occurred. Transbrachial vascular approach for arterial interventions in iliac and femoro-popliteal pathologies is a reasonable alternative to the transaxillary access if transfemoral puncture has to be avoided. The technical success rate is comparable with the results of the transaxillary and transfemoral approach. To minimize, at least theoretically, the risk of cerebral complications, the left-sided approach should be preferred and intravenous heparin should be administered routinely.

Patency of Superficial Femoral Vein Employed as a Crossover Femoral Artery Bypass Conduit

This study assesses the patency of superficial femoral vein used as a crossover femoral artery bypass conduit in patients presenting either with localized groin sepsis, generalized sepsis or in patients with occluded or heavily diseased superficial femoral artery outflow. Twenty patients were followed prospectively with femoral crossover grafts constructed of superficial femoral vein. Twelve patients presented with sepsis and 8 with chronic ischemia from iliac artery occlusion and severely diseased superficial femoral artery outflow. Graft patency was assessed with regular duplex ultrasound examination. There was one perioperative death. Six patients died during the follow-up period. Mean follow-up time was 24.3 months. No graft occluded or required revision. There was no limb loss, graft infection, or graft hemorrhage. Superficial femoral vein offers an effective femoral crossover bypass graft in patients with either localized/generalized sepsis or disadvantaged outflow tracts.

Aortic Reconstruction in Patients with Functioning Renal Allografts

Patients with functioning renal allografts requiring aortic reconstruction pose a considerable challenge to the vascular surgeon. A variety of strategies for renal allograft preservation during intervention have been described including hypothermia, indwelling shunts, cold renal perfusion, axillofemoral bypass, and endovascular stent-grafting. Reported here are two cases of successful aortic reconstruction utilizing standard open surgical techniques designed simply to minimize warm renal ischemia. The first case was that of a 55 year-old patient with a functional renal allograft originating from the right external iliac artery, who presented acutely with large symptomatic aortic and bilateral iliac artery aneurysms. He was treated with aorto-right femoral/left iliac bypass grafting. The right femoral anastomosis was performed first so that warm renal ischemia was limited to the 34 min required to perform the proximal end-to-end aortic anastomosis. The second case was that of a 44-year-old patient also with a transplanted kidney originating from the right external iliac artery. He presented with worsening hypertension, decreasing renal function, claudication, and severe aortoiliac occlusive disease. He was treated with aorto-left femoral bypass grafting via a retroperitoneal approach, followed by femorofemoral crossover bypass for retrograde perfusion of the kidney (total warm ischemia time 20 min). Both patients recovered uneventfully without a decrement in renal function and remain well on follow-up. It is concluded that standard open surgery without adjunctive shunts or bypasses remains a viable treatment option for these patients, provided warm renal ischemia can be minimized.

Functional outcome after thoracoabdominal aortic aneurysm repair

Objective: Repair of thoracoabdominal aortic aneurysms (TAAAs) is performed for the improvement of long-term survival and the preservation of function. The determination of functional outcome and the identification of predictors of survival and functional recovery after TAAA repair are key to proper patient selection. Methods: This retrospective review of clinical data was performed in an academic medical center. The demographics, Crawford aneurysm type (I-18, II-33, III-22, IV-28), preoperative risk factors, operative characteristics, and postoperative complications and outcomes were recorded from the medical records for 101 consecutive patients who underwent TAAA repair (58 elective and 43 urgent/emergent). Functional status and living situation at hospital discharge and 12 months after discharge were determined from follow-up examination records or telephone contact with surviving patients. The patients then were categorized into “good” (survival, home, discharge to rehabilitation center, ambulatory) or “bad” (death, discharge to or residence in a long-term care facility, non-ambulatory) outcomes. Results: The postoperative mortality rate was 17.8% (10% in elective cases and 28% in urgent cases), and significant postoperative complications occurred in 77% of the cases (pulmonary complications in 41%, renal complications in 28%, and cord injury in 12%). The mean length of stay was 22.8 + 23.6 days, and at discharge, 80% of the patients were sent to home or rehabilitation and 20% were sent to long-term care facilities. At 1 year, 15 additional patients had died. All but two patients who had been initially discharged to rehabilitation had returned home, but only two patients who had been discharged to long-term care facilities had returned home and both were nonambulatory. Therefore, the survival rate at 1 year was 67%, and only 52.4% of the patients had a “good” outcome at 1 year (survival rate was 78% and rate of “good” outcome was 63% in patients who underwent elective TAAA repair). Independent predictors of postoperative death and “bad” outcome were age more than 75 years, preoperative heart disease, duration of visceral ischemia, use of left atrial femoral bypass graft, postoperative renal dysfunction, and number of organs failing after surgery. Conclusion: Survival and good functional outcome after TAAA repair is significantly less common than expected and is primarily predicted with intraopertive factors and postoperative complications. Improved operative techniques and limitation of visceral ischemia reperfusion injury may improve outcome after TAAA repair. (J Vasc Surg 2002;35:640-7.)

Video-assisted aortic surgery

Background: There are several laparoscopic techniques that can be used to perform a total or video-assisted aorto–femoral bypass grafting procedure. Major drawbacks of laparoscopic aortic surgery are the long operating times and the steep learning curve required for these procedures. Hand-assisted laparoscopy is a novel technique that allows surgeons to use their hands and laparoscopic instruments in the operative field while maintaining a pneumoperitoneum. Study Design: A prospective nonrandomized study was conducted in a community medical center. Any patient with aortoiliac occlusive disease or an abdominal aortic aneurysm who was determined to be suitable for a laparoscopic aorto–femoral bypass grafting procedure was included in the study. The main outcomes measured were: operating time, aortic cross-clamp time, incision size, complications, conversion rate to an open procedure, length of stay in the ICU, and postprocedural hospital stay. A concurrent control group of 20 patients was compared with the minimally invasive group. Results: Forty-one consecutive patients were scheduled for the laparoscopic operation. Conversion to an open procedure was necessary in three patients. There were two major complications, including the development of renal failure in one patient who died 28 days postoperatively. The mean postprocedural hospital stay was 4.5 ± 2.5 days (range 2 to 15 days). The mean operating time was 163.1 ± 38.7 minutes, including an aortic cross-clamp time of 38.3 ± 9.7 minutes. Postoperative hospital stay and the time required in the ICU were significantly shorter after the laparoscopic procedure compared with a conventional bypass grafting procedure. Conclusions: Hand-assisted laparoscopy is a minimally invasive technique with operating times and outcomes similar to those of conventional procedures. The possibilities of this technique in patients with aortoiliac disease should be evaluated in a prospective randomized study.

Vein interposition cuffs decrease the intimal hyperplastic response of polytetrafluoroethylene bypass grafts

Purpose: The modification of the distal anastomosis of polytetrafluoroethylene (PTFE) bypass grafts with vein interposition cuffs (VCs) has been reported to increase graft patency. However, the mechanisms that are responsible for this improved patency are unclear. Because intimal hyperplasia (IH) is a primary cause of prosthetic graft failure, we hypothesized that VCs affect the distal anastomosis by decreasing the IH response of the outflow artery. Methods: Twenty-three female domestic Yorkshire pigs (mean weight, 35 kg) underwent 42 femoral PTFE bypass grafting procedures. The PTFE bypass grafts were separated into the following three groups according to distal anastomotic configuration: end-to-side anastomoses (ES), VCs, and cuffs constructed with PTFE (PCs). Four femoral arteries from two pigs served as healthy controls. At sacrifice, the grafts were perfusion fixed, and the distal anastomoses harvested at 1 and 4 weeks. The specimens were hemisected and serially sectioned to identify the heel, toe, and mid-anastomotic regions. The sections were cut into 5-μm segments and analyzed for intima and media thickness and area, intima/media area ratio, and the distribution of IH in the vein cuff. The roles of transforming growth factor–β1 and platelet-derived growth factor–BB in IH development were assessed with immunohistochemistry. Results: IH development was significantly lower at all areas of the anastomosis, with VCs compared with ES and PCs at 4 weeks ( P ≤ .001). IH decreased in VCs from 1 to 4 weeks in all areas of the anastomosis ( P ≤ .001). PCs showed pronounced IH at the mid-anastomosis as compared with VCs and ES ( P ≤ .001). IH was most pronounced at the toe with ES and PCs ( P ≤ .001). Qualitatively, VCs altered the site of IH development, sparing the recipient artery with preferential thickening of the vein cuff and formation of a pseudointima at the vein-PTFE interface. Immunohistochemistry results showed positive staining for transforming growth factor–β1, platelet-derived growth factor–BB, and smooth muscle α-actin in the hyperplastic intima. Conclusion: PTFE bypass grafts with VCs had less IH develop than did grafts with ES and PC anastomoses. IH regression in VCs at 4 weeks suggests compensatory vessel wall remodeling mediated by the presence of the VC. Furthermore, VCs caused a redistribution of hyperplasia to the vein-PTFE interface, delaying IH-induced outflow obstruction in the recipient artery. The marked increase in IH with PCs, despite a similar geometric configuration to VCs, suggests that the biologic properties of autogenous tissue dissipate IH development. Similarly, the flow patterns in PCs and VCs should be identical, which suggests a less important role of hemodynamic forces in VC-mediated protection. (J Vasc Surg 2000;31:69-83.)

Improved graft patency and altered remodeling in infrainguinal vein graft reconstruction for aneurysmal versus occlusive disease

Purpose: This study attempted to determine whether autogenous vein used for infrainguinal reconstruction in patients with aneurysmal disease might demonstrate an altered adaptive response compared with those patients who underwent reconstructive surgery for occlusive disease, potentially altering graft patency. Methods: From 1974 to 1997, 43 patients underwent vein grafting for 60 popliteal artery aneurysms (PAA). Results: In an attempt to monitor early vein graft adaptation, serial graft surveillance by Duplex ultrasound scan was performed in a statistically valid subset of age-, sex-, and distal anastomotic site–matched patients with PAA and patients with occlusive disease (OD; n = 8 PAA; n = 8 OD). Compared with an age-matched and sex-matched cohort of patients (n = 60 grafts in each group) with occlusive disease and who had femoral below-knee bypass grafts (FBP) only, patients undergoing infrainguinal reconstruction for PAA had a higher 5-year primary graft patency (92% ± 4% for PAA vs 66% ± 7% for FBP; P < .01). Duplex surveillance demonstrated a progressive increase in arterialized vein graft diameter in the PAA group versus the OD group. In univariant analysis, aneurysmal disease was a significant predictor of final follow-up diameter ( P = .002). In a linear regression model, controlling for diameter at first follow-up after bypass grafting, first follow-up diameter was also predictive of final follow-up diameter. Conclusion: These data suggested altered remodeling of vein grafts in patients with popliteal artery aneurysm, which may have a beneficial effect on patency. (J Vasc Surg 1999;29:1022-30.)

Vascular graft healing: I. FTIR analysis of an implant model for studying the healing of a vascular graft

FTIR analysis of sequential biopsy samples of the primary and replacement segments obtained from 70 to 80-cm long carotid–femoral bypass grafts implanted bilaterally in the dog indicate that the healing pattern is similar over the entire length of these grafts. Preliminary analysis of the spectra also indicates that the major developments in the formation of the biological layer appear to occur during the first 4 weeks after implantation. Collagen IV could be detected by both FTIR and antibody staining in the 8-week samples. Thus, this study supports the application of FTIR attenuated total reflectance to determine the components of the biological tissue that forms on an implanted vascular graft surface. © 1999 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 48: 172–186, 1999

26.10 Favorable flow dynamics of sequential femoral distal bypass grafts in patients with severe limb ischemia

26.10 Favorable flow dynamics of sequential femoral distal bypass grafts in patients with severe limb ischemia