Prosthetic Bypass Grafts Research Articles

Three-month cumulative incidence of thromboembolism and bleeding after periprocedural anticoagulation management of arterial vascular bypass patients

The objective of this study was to determine 3-month cumulative incidence of peri-procedural thromboembolism (TE) including graft occlusion, and peri-procedural bleeding for chronically anticoagulated vascular bypass graft (BG) patients requiring temporary warfarin interruption for an invasive procedure. Appropriate peri-procedural management of patients receiving chronic warfarin therapy to preserve lower extremity arterial BG patency is unknown. In a protocol driven, cohort study design, all BG patients referred to the Mayo Clinic Thrombophilia Center for peri-procedural anticoagulation (1997-2007) were followed forward in time to estimate the 3-month cumulative incidence of TE and bleeding. Decisions to provide "bridging" low molecular weight heparin (LMWH) were individualized based on estimated risk of TE and bleeding. There were 78 BG patients (69 ± 10 years; 38% women), of whom 73% had a distal autogenous and 53% had prosthetic BG; 45% received antiplatelet therapy. Peri-procedural LMWH was prescribed for 77% of patients and did not vary by BG distal anastomosis location or type. The 3-month cumulative incidence of TE was 5.1% (95% CI 1.4-12.6), including two BG occlusions, one DVT, and one myocardial infarction. Major bleeding occurred in 1 patient (1.28%, 95% CI 0.0-6.94). One patient died due to heart failure. TE and bleeding did not differ by bridging status. The 3-month cumulative incidence of TE among BG patients in whom warfarin is temporarily interrupted for an invasive procedure may be higher than in other "bridging" populations (atrial fibrillation, prosthetic heart valve, venous thromboembolism). This finding underscores the often tenuous nature of distal bypass grafts necessitating an aggressive approach to peri-procedural anticoagulation management.

Spiral Laminar Flow Prosthetic Bypass Graft: Medium-Term Results From a First-In-Man Structured Registry Study

A number of surgical strategies and graft enhancements have been trialled to improve the performance of prosthetic grafts. Neointimal hyperplasia may, in part, be a normal cellular response to an abnormal (turbulent) flow environment. This first-in-many study assesses the safety and medium-term patency performance of a new graft designed to induce stable laminar flow through the distal anastomosis. Forty patients who required an infrainguinal bypass graft were recruited/registered from a number of centers in Belgium and The Netherlands. Thirty-nine received a Spiral Laminar Flow graft as part of a standard treatment protocol (23 above-the-knee and 16 below-the-knee bypasses). Kaplan-Meier analyses were used to calculate primary and secondary patency rates. The 12-, 24-, and 30-month primary patency rates were 86%, 81%, and 81% for above-the-knee bypasses and 73%, 57%, and 57% for below-the-knee bypasses, respectively. In the case of secondary patency rates, numbers were unchanged for above-the-knee bypasses and were 86%, 64%, and 64%, respectively, for below-the-knee bypasses. There were no amputations in the study population. This first-in-man series shows potential for the idea of spiral flow-enhanced prosthetic grafts. As always, randomized studies are required to explore the role of different enhanced prosthetic grafts.

Abstract 124: Survival and Limb Salvage Following Lower-Extremity Revascularization Using Cryopreserved Saphenous Vein Allograft

OBJECTIVE: Revascularization options for critical limb ischemia are often limited by the lack of autologous vein conduit, particularly in the setting of infection or distal targets that render the use of synthetic graft undesirable. Cryopreserved saphenous vein allograft (CSVA) may provide an important alternative. We conducted a retrospective study of patients undergoing lower extremity revascularization at a single institution using CSVA. METHODS: Between April 2009 and June 2011, 18 CSVA were used for bypass (12 men) with a median age of 65 (range, 45-88) years. Procedures included 14 femoral-distal bypasses (5 femoral-below-knee popliteal, 9 femoral-tibial bypasses) and 4 femoral-femoral bypasses. No immunosuppression was used. Follow-up was continued until conduit revision, amputation, death, or the end of the study period. End points included patency, limb salvage, and survival. RESULTS: Comorbidities included smoking history (95%), hyperlipidemia (73%), hypertension (68%), coronary artery disease (52%), diabetes (32%), obesity (16%), and atrial fibrillation (21%). The majority of patients had undergone multiple failed endovascular or open revascularization procedures prior to the use of CSVA. Clinical presentations included initial bypass thrombosis (26%), infection involving synthetic conduit (16%), stenosis (16%), and anastomotic pseudoaneurysm (5%). CSVA was used at the index procedure in 31% of cases, only when autologous vein was found to be inadequate for distal bypass. Complications following CSVA implantation included thrombosis (31%), stenosis (16%), infection (5%), aneurysmal degeneration (15%), and anastomotic pseudoaneurysm (5%). Survival was 78% with a median follow-up time of 285 (range, 2-850) days. Limb salvage was achieved in 12 of 14 surviving patients (86%) with graft patency maintained in 10 of 14 patients (71%) over a median 300 (range, 60-850) days. CONCLUSION: CSVA may provide an important option in clinical situations where autologous vein is not available and prosthetic bypass graft undesirable due to low patency rates or high rates of reinfection. Further elucidation of factors related to CSVA bypass patency should guide patient selection and management.

Long-Term Quality of Life and Mobility After Prosthetic Above-the-Knee Bypass Surgery

Multiple studies have addressed above-the-knee femoral artery bypass grafting; however, information on late quality of life (QoL) and mobility is scarce. We studied long-term QoL and mobility after above-the-knee bypass surgery. Consecutive patients presenting with claudication, ischemic rest pain, or gangrene who received above-the-knee prosthetic bypass grafting between December 1997 and January 2003 were included in this observational study. Data used were recorded in a prospectively collected database of patients receiving Dacron and polytetrafluoroethylene (PTFE) supragenicular bypasses for lower limb ischemia. Primary outcomes were QoL and mobility, and secondary outcomes were patency and patient survival. QoL was measured with the EuroQol questionnaire (EQ-5D/EQ-VAS). Mobility was assessed with the Walking Impairment Questionnaire (WIQ) and analyzed in univariate and multivariate models. Patency and survival were computed with Cox regression. One hundred forty patients were treated during the study period. Sixty-nine patients (50%) died during follow-up, leaving 71 survivors who were asked (63 [89%] complied) to complete the EQ-5D/EQ-VAS and WIQ questionnaires. None of the primary outcome parameters (WIQ, EQ-5D, EQ-VAS) were affected by primary bypass occlusion (p = 0.34, p = 0.44, and p = 0.27, respectively) or long-term patency (p = 0.07, p = 0.54, and p = 0.36, respectively). Male sex was significantly associated with a better outcome on all primary outcome parameters. Patients with Dacron versus PTFE grafts had WIQ scores of 0.49 and 0.26, respectively (p = 0.01). EQ-5D scores of patients with Dacron and PTFE were 0.576 and 0.409 (p = 0.08) and EQ-VAS scores were 61 and 54, respectively (p = 0.24). Graft type was not independently associated with occlusion, but runoff was. The 5-year and 10-year patient survival rates were 58% and 51%, respectively. In this study, long-term QoL and mobility did not seem to be associated with bypass patency, as assessed in a single late follow-up. Revision of bypasses did not contribute to long-term QoL and walking ability. Therefore, the necessity of graft surveillance and subsequent revision and/or thrombectomy in case of synthetic bypass failure in absence of critical limb ischemia seems to be questionable.

VASCULAR GRAFT INFECTIONS MANAGEMENT

Introduction: Despite routine antibiotic prophylaxis and refinements in implantation technique, microbial infection of the vascular prostehesis can occur. Infection involving a vascular graft is difficult to eradicate. If not recognized or treated promptly, implant failure will occur by producing sepsis, hemorrhage or thrombosis. Management involves graft excision alone, graft preservation within the implant wound, in/situ graft replacement, or graft excision in conjunction with extra-anatomic bypass grafting. Matherial and method: We retrospectively analysed the operative registers of our clinic as well as the regular archives, from 2000 until 2008, searching for reported graft infections which needed excisions and extraanatomical bypasses or for conservative therapy. There were 50 patients in this interval admitted and treated in Surgical Clinic No.1, out of a total of 950 vascular interventions. 10 of them were early graft infections( 4 months). Using Szilagyi’s classification, 10 were grade I, 17 were grade II and 23 grade III.We followed antibiotic prophylaxis protocols in all of the cases, prior to first vascular intervention. Staphylococcus aureus was the most prevalent pathogen ( 95% ) found affecting our grafts. Results: We performed 20 graft excisions for infrainguinal graft infections, with the removal of the entire graft, radical debridement of infected perigraft tissues, closure of the arteriotomies with monofilament suture and the administration of systemic and topical antibiotics. We attempted graft preservation in 5 cases of infrainguinal prosthetic bypass graft infection( with serial surgical wound debridement, coupled with antibiotic therapy, early muscle flap coverage and repeated wound cultures to identify any development of bacterial resistance or change in the microbial flora). We used the staged approach in 20 cases, beginning with drainage of the perigraft abscess, followed in 2 or 3 days by graft excision and autogenous vein grafting. We performed none in-situ replacements with Rifampin-bonded prosthesis, partly because they were not available until a few years. For the patients with infection localized to only a portion of an aortofemoral graft, we preferred, for the decreased morbidity, the excision of the infected portion of the graft(partial graft excision) and after solving the inguinal infection, a staged extra-anatomical bypass- in cases.As for the gold standard regarding the aortic graft- total graft excision and ex-situ bypass, we only performed 5 of them. 3 patients died and 2 required major amputation. Conclusions: Dissatisfaction with the morbidity and the mortality of treating vascular graft infections, regardless of location, by total graft excision and remote bypass has been the impulse for the expanded application of lately performed in-situ bypasses or even for the prophylactic use of antibiotic-bonded grafts, in carefully selected cases.

Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) and the (hoped for) dawn of evidence-based treatment for advanced limb ischemia

The Bypass versus Angioplasty in Severe Ischemia of the Leg (BASIL) trial is the only randomized controlled trial (RCT) to date comparing open surgical bypass with endovascular therapy for severe limb ischemia (SLI). In their initial 2005 publication, the BASIL investigators reported that the main clinical outcomes (overall survival and amputation-free survival) were no different at 2 years after randomization to angioplasty-first or bypass-first revascularization strategies. However, beyond 2 years there appeared to be a benefit for open bypass surgery, providing impetus for an extension study. The final analysis of the long-term outcomes from BASIL is now presented in a set of articles that are reviewed in this commentary. The benefit of initial randomization to open surgery for patients surviving > or =2 years (70% of the BASIL cohort) was confirmed. When outcomes were analyzed by treatment received, patients who had received prosthetic bypass grafts (25% of the surgical arm) fared much more poorly than those treated with a vein bypass. Patients who underwent surgical bypass after an initial failed angioplasty also fared significantly worse than those who were treated initially with bypass surgery. Health-related quality of life measures and costs were not significantly different overall. There are many controversies surrounding the BASIL trial and its interpretation, which are reviewed herein. These include the choice of study population, end points examined, and the nature of procedures performed. The BASIL trial confirms the primacy of open surgical bypass with vein for most patients with SLI and raises questions about the sequelae of failed endovascular interventions. Further multicenter trials are needed to address the large gap in evidence for treatment selection in this patient population.

Primary Stent in Occluded Femoropopliteal Bypass Graft in a Patient with Contraindications for Thrombolytic Therapy: Case Report

Endovascular or surgical treatment of femoropopliteal bypass (FPB) graft occlusion is a safe and effective procedure. However, there are some reports that recommend thrombolysis as an initial therapy [1, 2]. In situ thrombolysis (ITL), with later percutaneous transluminal angioplasty (PTA) of any anastomotic stenoses, is the usual endovascular therapy for this condition [1, 2]. On the other hand, there are cases where ITL, as well as primary stenting, may be contraindicated because of the relative risk of distal embolization [3]. We report a case of acute occlusion of a femoropopliteal prosthetic bypass graft where ITL was contraindicated, which was successfully treated with primary stenting. To our knowledge, this is the first report of primary stenting in acute FPB occlusion.

Femoropopliteal prosthetic bypass graft infection due to Mycobacterium abscessus localized by FDG-PET/CT scan

A patient with postvascular graft placement presented with bacteremia but no localizing symptoms. Our standard infected graft workup of computed tomography (CT) scan, ultrasound scan, magnetic resonance imaging (MRI) scan, and additional laboratory tests did not localize the infection source. Nuclear medicine had three options including white blood cell (WBC) scan, gallium scan, and the fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT scan. FDG-PET/CT imaging alone demonstrated the location. We present an unusual case of Mycobacterium abscessus in a vascular graft not localized with CT scan, ultrasound scan, or MRI scan and could only be localized with FDG-PET/CT scan.

Predictors of Prosthetic Graft Infection after Infrainguinal Bypass

Background Some patients require major leg amputation after lower-extremity prosthetic bypass for graft occlusion or failure of wound healing, despite a patent graft. Amputation above or below the knee was hypothesized to increase susceptibility to prosthetic graft infection in the ipsilateral extremity. Study Design All patients undergoing implantation of prosthetic infrainguinal arterial bypass grafts identified from a vascular surgical registry during a 12-year period were reviewed. Patient demographic data, comorbid conditions, and operative details were evaluated as risk factors, with graft infection among the primary outcomes of interest. Results Prosthetic graft infection occurred in 25 of 141 (18%) infrainguinal grafts and occurred most frequently after major amputation (41% versus 6%; odds ratio [OR] = 12; 95% CI, 4.1 to 34) or early reoperation after initial grafting (70% versus 16%; OR=11; 95% CI, 1.9 to 63). Risk was highest after amputation within 4 weeks of bypass (70% versus 32%; OR=5.0; 95% CI, 1.1 to 23). Graft thrombosis (84% versus 39%; OR=8.3; 95% CI, 2.7 to 26) and presence of gangrene (52% versus 23%; OR=3.6; 95% CI, 1.5 to 8.7) also increased infection risk. Independent predictors for development of graft infection were identified by stepwise regression analysis to be amputation (p Conclusions Amputation increases risk of prosthetic graft infection, especially when performed early or after failed revascularization. Consideration should be given to partial or complete removal of a prosthetic graft above the level of the amputation under these conditions.

Postendocarditis mitral valve aneurysm

Mitral valve aneurysm is defined as a localized, thin-walled, saccular bulge of the mitral leaflet toward the left atrium. In this study, we report a case of mitral aneurysm of the posterior leaflet (scallop P3) secondary to primary mitral endocarditis in a patient who underwent prosthetic aortic valve replacement and coronary artery bypass graft.

Case Study: Chronic Femoropopliteal Prosthetic Graft Infection With Exposed Graft

One of the most feared complications following vascular reconstruction is infection due to the attendant risks of limb loss, sepsis, or death. The reported incidence of infection following infrainguinal prosthetic graft infection is 2.5% with associated mortality rates and amputation rates of 18% and 41%, respectively. There are several options in treating infected prosthetic infrainguinal bypass grafts. Some authors have advocated complete removal of the infected graft with concomitant in situ revascularization using autogenous tissue or extra-anatomic bypass using either autogenous or prosthetic material, depending upon the clinical circumstances. Other authors have advocated attempting graft preservation to decrease the risk of amputation. Infected, thrombosed grafts are generally treated with graft excision alone with care taken to preserve collateral flow. The treatment options may also be influenced by the type of infection, as infections caused by gram-negative bacteria are thought to be more virulent than those associated with gram-positive bacteria. We recently treated a patient with an 18-month history of an exposed prosthetic graft in the groin, which was infected by Proteus mirabilis. Despite the extended period of graft exposure and despite gram-negative bacteria being the causative organism, the patient reported only intermittent drainage of pus from the groin. The management of this unusual infection forms the basis of this report.

Early Results for Below-Knee Bypasses Using Distaflo

In patients who require lower extremity revascularization, prosthetic graft is a reasonable alternative in the absence of a suitable autologous vein conduit. However, prosthetic bypass grafts have limited patency, especially for infrageniculate reconstruction. Polytetrafluoroethylene grafts were geometrically modified at the distal end to increase their patency. The authors reviewed their experience with the Distaflo graft in patients who required lower extremity below-knee popliteal and tibial bypasses when no suitable autologous vein conduit was available. Chart review was conducted of the 57 patients who underwent 60 lower extremity bypasses over a 3-year period between June 2003 and April 2006. Twenty-four revascularizations were constructed to the tibial outflow sites, whereas the remaining grafts were placed to the below-knee (28) and above-knee (8) popliteal artery, respectively. Study endpoints were primary, assisted primary, secondary patency, and limb salvage at the time of follow-up. Distaflo bypass was performed at the infrageniculate level in 86.7% of cases (28 below-knee popliteal, 24 tibial). Mean follow-up time was 12 months (range, 0.5-37.5 months). At 1 year, primary, assisted primary, and secondary patencies and limb salvage rates for below-knee popliteal bypasses were 83.5%, 89.5%, 94.7%, and 94.4%, respectively. Primary, assisted primary, and secondary patencies and limb salvage rates for tibial bypasses were 44.4%, 44.4%, 63.2%, and 74.9%, respectively. Distaflo precuffed graft is a good alternative conduit for below-knee popliteal and tibial lower extremity reconstructions in the absence of an autologous vein and appears to have promising early patency and limb salvage rates even when used for tibial bypasses.

Construction and characterization of a thrombin-resistant designer FGF-based collagen binding domain angiogen

Humans demonstrate limited spontaneous endothelialization of prosthetic bypass grafts. However the local application of growth factors to prosthetic grafts or to injured blood vessels can provide an immediate effect on endothelialization. Novel chimeric proteins combining potent angiogens with extracellular matrix binding domains may localize to exposed matrices and provide sustained activity to promote endothelial regeneration after vascular interventions. We have ligated a thrombin-resistant mutant of fibroblast growth factor (FGF)-1 (R136K) with a collagen binding domain (CBD) in order to direct this growth factor to sites of exposed vascular collagen or selected bioengineered scaffolds. While FGF-1 and R136K are readily attracted to a variety of matrix proteins, R136K-CBD demonstrated selective and avid binding to collagen ∼4x that of FGF-1 or R136K alone ( P<0.05). The molecular stability of R136K-CBD was superior to FGF-1 and R136K. Its chemotactic activity was superior to R136K and FGF-1 (11±1% vs. 6±2% and 4±1%; P<0.01). Its angiogenic activity was similar to R136K and significantly greater than control by day 2 ( P<0.01). After day 3, FGF-1-treated endothelial cell's (EC) sprouts had regressed back to levels insignificant compared to the control group ( P=0.17), while both R136K and R136K-CBD continued to demonstrate greater sprout lengthening as compared to control ( P<0.0002). The mitogenic activity of all growth factors was greater than control groups (20% PBS); in all comparisons ( P<0.0001). This dual functioning angiogen provides proof of concept for the application of designer angiogens to matrix binding proteins to intelligently promote endothelial regeneration of selected matrices.

A Reproducible Porcine ePTFE Arterial Bypass Model for Neointimal Hyperplasia

Late failure of prosthetic vascular bypass grafting using expanded polytetrafluoroethylene (ePTFE) is secondary to the development of neointimal hyperplasia, most commonly at the distal anastomosis. To develop therapies that can improve upon current prosthetic vascular bypass grafting, a large animal model of prosthetic bypass grafting that results in reproducible neointimal hyperplasia is necessary. We performed bilateral end-to-side carotid artery bypasses with 6 mm ePTFE in a porcine model (n = 11). We studied graft patency using magnetic resonance angiography (MRA, 3 wk), duplex ultrasonography (4 wk), and digital-subtraction contrast angiography (4 wk). Animals were sacrificed at 4 wk and morphometric analysis was performed. Of the 11 animals that underwent surgery, one pig died from respiratory compromise; of the remaining 10, graft patency was 90% at 4 wk. Peak systolic and end diastolic velocities were established for this model using ultrasonography. MRA, ultrasonography, and angiography confirmed graft patency and were complimentary tools to evaluate the grafts. Development of neointimal hyperplasia was reproducible at 4 wk in both the proximal and distal anastomoses (2.5 to 3 mm(2)) of the ePTFE bypass grafts. We developed a reproducible porcine ePTFE carotid artery bypass model for studying neointimal hyperplasia. Not only does this model allow for the manipulation and evaluation of potential therapies, but patency and neointimal hyperplasia can be easily evaluated by traditional means, such as MRA, ultrasonography, and angiography. This preclinical model is ideal for evaluation of novel therapies in vivo designed to inhibit neointimal hyperplasia following arterial reconstruction with prosthetic bypass grafting.

Endovascular Treatment of Aneurysmal Deterioration in Peripheral Arterial Allografts

To report endovascular treatment of 2 patients with aneurysmal deterioration of peripheral arterial allografts. Two men (65 and 64 years old) who had undergone an arterial allograft reconstruction for infection of prosthetic infrapopliteal bypass grafts 5 and 7 years ago, respectively, were diagnosed with asymptomatic aneurysmal deterioration of the allografts. Stent-graft repair was successful in both cases, completely excluding the aneurysms. At >or=1 year, continued aneurysm exclusion was confirmed by duplex scan, with no evidence of endoleak, migration, or stenosis. Endovascular treatment may be a useful therapeutic option when treating patients with late peripheral allograft deterioration.

Surgical treatment of aortic coarctation under normothermia without cardiopulmonary bypass: a report of 15 cases

To evaluate the early and mid-term outcome of surgical repair for post-ductal coarctation of the aorta (CoA) under normothermia without cardiopulmonary bypass. Clinical data from 15 patients (11 males, 4 females, mean age 18 +/- 10 years) undergoing surgical repair for post-ductal CoA under normothermia without cardiopulmonary bypass between January 1999 and December 2004 were analyzed retrospectively. There were 7 isolated cases, 7 cases associated with patent ductus arterious (PDA), 1 case with PDA and ventricular septal defects. Operation was performed under normothermia with partial cross-clamping of descending aorta in 8 cases, compete cross-clamping in 6 cases and temporary shunt in 1 case. Operative techniques adopted prosthetic bypass graft in 9 cases, Gore-Tex patch graft aortoplasty in 4 cases and stenosis resection with end-to-end anastomosis in 2 cases. PDA was ligated at single-stage in 8 cases. Ventricular septal defect was repaired at second stage in 1 case. No early and late death. Hypertension occurred in 9 cases during early postoperative period but was normalized gradually in 5 cases without medication during follow-up period, from 6 months to 5 years. The arterial blood pressure of lower extremities increased significantly and no hoarseness, paraplegia occurred after operation. No recoarctation and aneurysm formation were found during follow-up. Surgical repair of post-ductal CoA under normothermia without cardiopulmonary bypass is safe and effective, which is a procedure of choice for patients with isolated CoA, CoA associated with PDA, or with other intracardiac anomalies that are ready to be repaired at second-stage.

The role of vein grafts in peripheral vascular disease and carotid artery disease

BACKGROUND: Peripheral bypass surgery has become a widely used and beneficial treatment in patients with peripheral arterial occlusive disease. METHODS: Review of the literature. RESULTS: Even though prosthetic bypass grafts are being constantly refined, vein grafts are still unsurpassed in terms of safety and efficacy for almost all indications. In order to assure long-term benefit for the patient, postoperative surveillance and concomitant medical treatment are important. Carotid endarterectomy has been performed extensively to reduce the risk of stroke from carotid artery disease. Vein grafts play a prominent role, but controversy still exists about the optimal type of patch for arteriotomy closure. Recent systematic reviews suggest that there are small, if any, differences between vein and prosthetic patches. CONCLUSIONS: Despite constant improvement of prosthetic vascular graft materials, autologous vein grafts are still of eminent importance in modern vascular surgery.

FDG-PET and FDG-PET/CT for Diagnosing Infection in Patients with Multiple Vascular Bypass Grafts: A Report of Two Cases

2-Deoxy-2-[ 18 F]fluoro- d -glucose (FDG) positron emission tomography (PET) is an established imaging modality in the fields of clinical oncology, cardiology and neurology, and could be useful for the diagnosis of vascular prosthetic graft infection. The technology of combining FDG-PET and computed tomography (CT) images, acquired in a single session, is gaining popularity. Several reports proposed the application of both FDG-PET and FDG-PET/CT in the diagnosis and management of vascular prosthetic graft infection. This case report highlights the usefulness of FDG-PET and FDG-PET/CT as noninvasive diagnostic modalities for patients with multiple vascular prosthetic bypass grafts susceptible for infection.

Combined Endovascular and Surgical Treatment of Infected Carotid-Carotid Bypass Graft

To present a complex case involving an infected carotid-carotid bypass graft that was successfully treated with a stent-graft and subsequent surgical removal of the infected graft. A 75-year-old woman presented with persistent purulent drainage of an infected and exposed carotid-carotid prosthetic bypass graft. Wound cultures revealed methicillin-resistant Staphylococcus aureus. She was treated with appropriate intravenous antibiotic therapy without improvement in wound drainage. Because of her comorbid conditions, a decision was made to pursue endovascular revascularization of her left and right common carotid arteries (CCA), with subsequent surgical removal of the infected prosthetic graft. The patient underwent balloon angioplasty; a 7x18-mm Omnilink stent was deployed in the innominate artery and a 7x18-mm Herculink stent in the ostial left CCA. During the same procedure, the carotid-carotid bypass graft was excluded with deployment of an 8x50-mm Viabahn stent-graft in the right CCA. Several days later, the infected and now thrombosed carotid-carotid bypass graft was surgically removed, and an area of adjacent muscle was used to patch the previously excluded connection of the bypass from the right CCA. A saphenous vein patch was used to repair the defect in the left CCA. Her postoperative course was uneventful. At 1 year, the clinical and duplex examinations revealed satisfactory wound healing and patent left and right CCAs. This case indicates that a combined endovascular and surgical approach may be a safe and effective option in the treatment of carotid-carotid bypass graft infection.

The treatment of failed low limb prosthetic graft bypass for the chronic low limb ischemia: a report of 19 cases

To determine the optimal strategies of occluded prosthetic bypass and to assess the risk factors which influence the outcome. From September 2003 to December 2004, 19 cases of failed low limb prosthetic graft were treated in the Peking Union Medical College hospital. All of them underwent operation, and the strategies of operation were determined by the cause assessed pre-procedure. Four cases underwent thrombectomy only, 5 cases underwent thrombectomy combined with the distal anastomosed-plasty, 3 cases underwent thrombectomy combined with profundaplasty, 2 cases underwent vascular re-construction with new prosthetic graft, 1 case underwent external iliac artery endarterectomy, 2 cases underwent stent cell transplantation, and the last 2 cases underwent amputated since the limbs showed un-salvageable. All the cases got at least 1 year following-up. In the 17 vascular reconstruction cases except the 2 cases who underwent amputated, 14 cases (82.4%) got firstly successes, according to their limb ischemia symptom got well, but the rest 3 cases (17.6%) failed. And the mortality is 10.5% (2 cases). In the 1 year following-up, the prosthetic graft patency was 35.3% (6 cases), and the limb salvage was 76.4% (13 cases). Optimal resolution for prosthetic graft re-occlusion should be based on good judgment of the occlusion cause. Then proper correcting the cause plus right following-up program could be the risk factors of prognosis.