Lower Limb Bypass Surgery Research Articles

Deep Circumflex Iliac Artery as an Inflow Alternative for Lower Limb Bypass: Report of a Case

Introduction: The common femoral artery (CFA) is the most favourable inflow in all types of lower limb bypass procedures. However, sometimes, the CFA cannot be used in patients with critical limb ischaemia owing to obstruction, severe calcification or previous dissection. Here, we describe how iliopopliteal bypass was successfully performed by using a reversed saphenous vein graft in a patient with total occlusion of the CFA, superficial femoral artery (SFA) and deep femoral artery (DFA) and an entirely stented external iliac artery (EIA). The deep circumflex iliac artery (DCIA), which is an artery in the pelvis that runs along the iliac crest of the pelvic bone, was used as a source of inflow. Methods: A 62-year-old man with a severely ischaemic left foot was admitted to our hospital. His third and fifth toes were necrotised with pain at rest. Computed tomography revealed complete occlusion of the left CFA, SFA and DFA with severe calcification. Additionally, the left EIA had been entirely stented at another hospital 2 years previously. Arteriography revealed that the distal site of the stent in the EIA was at the border of the CFA and that the left CFA, SFA and DFA were occluded with severe calcification. The left DCIA was the only patent artery. Results: Lower limb bypass surgery was performed. The left EIA, CFA, SFA and DFA were exposed. The left EIA was totally stented, and the CFA, SFA and DFA showed severe calcification. There was no place to clamp the EIA. Even with occlusion of the EIA with a balloon, there would have been no space to anastomose the CIA. The left DCIA was 10 mm in diameter and was well pulsating, and it evolved as a collateral artery. Considering the occlusion condition, we selected the DCIA as a source of inflow. Subsequently, the left greater saphenous vein was exposed from the saphenofemoral junction to the ankle. The popliteal artery was exposed below the knee, and confirmed to be suitable for anastomosis. After systemic heparinisation, a 3.5-mm saphenous vein graft was anastomosed to the left DCIA in an end-to-side fashion with a continuous 7-0 polypropylene suture. The distal end of the saphenous vein graft was anastomosed to the distal zone of the left popliteal artery in an end-to-side fashion with a continuous 6-0 polypropylene suture. After completion of distal anastomosis, good pulsation was observed in the dorsalis pedis artery. Postoperative three-dimensional computed tomography revealed that bypass grafts were patent and that peripheral blood flow remarkably increased (Graphic). Although the third and fifth toes remained necrotised, the rest of the left foot became warm and the pain disappeared. The patient is currently undergoing a course of physiotherapy to help him perform activities of daily living. Conclusion: The CFA has been recognised and accepted as an important inflow source in lower limb bypass procedures. However, in clinical situations where the CFA, SFA and DFA cannot be used owing to obstruction, severe calcification or previous dissection, as in the present case, the DCIA evolving as a collateral artery can be considered as an effective alternative inflow in lower limb bypass.

Exercise-based Rehabilitation Improves Hemodynamic Responses after Lower Limb Arterial Blood Flow Surgery

Aim: The aim of this study was to evaluate the effectiveness of exercise rehabilitation programmed (ERP) on hemodynamic responses and functional status in patients after lower limb bypass surgery. Place and Duration of the Study: The study included 70 patients, who were treated in

Independence and mobility after infrainguinal lower limb bypass surgery for critical limb ischemia

Critical limb ischemia (CLI) is a common condition associated with high levels of morbidity and mortality. Most work to date has focused on surgeon-oriented outcomes such as patency, but there is increasing interest in patient-oriented outcomes such as mobility and independence. This study was conducted to determine the effect of infrainguinal lower limb bypass surgery (LLBS) on postoperative mobility in a United Kingdom tertiary vascular surgery unit and to investigate causes and consequences of poor postoperative mobility. We collected data on all patients undergoing LLBS for CLI at our institution during a 3-year period and analyzed potential factors that correlated with poor postoperative mobility. During the study period, 93 index LLBS procedures were performed for patients with CLI. Median length of stay was 11 days (interquartile range, 11 days). The 12-month rates of graft patency, major amputation, and mortality were 75%, 9%, and 6%, respectively. Rates of dependence increased fourfold during the first postoperative year, from 5% preoperatively to 21% at 12 months. Predictors of poor postoperative mobility were female sex (P = .04) and poor postoperative mobility (P < .001), initially and at the 12-month follow-up. Patients with poor postoperative mobility had significantly prolonged hospital length of stay (15 vs 8 days; P < .001). Patients undergoing LLBS for CLI suffer significantly impaired postoperative mobility, and this is associated with prolonged hospital stay, irrespective of successful revascularization. Further work is needed to better predict patients who will benefit from revascularization and in whom a nonoperative strategy is optimal.

Role of angiographic run off score as a tool to predict long term outcome following lower limb bypass surgery

s / International Journal of Surgery 11 (2013) 686e745 740 ABSTRACTS developed a total of 9 pseudoaneurysms (6.3%:one bilateral), none of which required secondary intervention. Median pseudoaneurysm diameter was 8.4mm at diagnosis. Median follow up was 24 months. Three pseudoaneurysms had resolved at one year and a fourth by 2 years. Four patients died at a median of 15 months; none due to pseudoaneurysms. Conclusion: There is a low rate of pseudoaneurysm formation after fascial closure and no clinical impact in the mid-term. Fascial closure remains a safe and minimally invasive option. 0963: OUTCOMES FOLLOWING ARTERIAL ANGIOPLASTY IN SYMPTOMATIC INFRAPOPLITEAL DISEASE: A SYSTEMATIC REVIEW OF THE LITERATURE James Glasbey , David Bosanquet , Michael Lewis . Department of Surgery, Royal Glamorgan Hospital, Llantrisant, South Wales, UK; Cardiff University School of Medicine, Cardiff, UK. Aim: Despite a wealth of research into percutaneous intervention for arterial disease, the role of angioplasty in treating symptomatic infrapopliteal disease remains undefined. Whilst historically, surgical revascularisation has been the cornerstone of its management, angioplasty is recommended for limb salvage where open surgery is contra-indicated. Should non-inferiority be demonstrated, increasing use of endovascular techniques may reduce the morbidity associated with open surgery. This study's aims are to summarise reported outcomes in endovascular crural disease management. Methods: A systematic review of the Cochrane Library, OVID/Medline and Pubmedwas performed from 1990 to December 2012.

International Variations in Infrainguinal Bypass Surgery – A VASCUNET Report

Objectives: To compare practice in lower limb bypass surgery in nine countries. Design: A prospective study amalgamating and analysing data from national and regional vascular registries. Methods: A table of data fields and definitions was agreed by all member countries of the Vascunet Collaboration. Data from January 2005 to December 2009 was submitted to a central database. Results: 32,084 cases of infrainguinal bypass (IIB) in nine countries were analysed. Procedures per 100,000 population varied between 2.3 in the UK and 24.6 in Finland. The proportion of women varied from 25% to 43.5%. The median age for all countries was 70 for men and 76 for women. Hungary treated the youngest patients. IIB was performed for claudication for between 15.7% and 40.8% of all procedures. Vein grafts were used in patients operated on for claudication (52.9%), for rest pain (66.7%) and tissue loss (74.1%). Italy had the highest use of synthetic grafts. Among claudicants 45% of bypasses were performed to the below knee popliteal artery or more distally. Graft patency at 30 days varied between 86% and 99%. Conclusions: Significant variations in practice between countries were demonstrated. These results should be interpreted alongside the known limitations of such registry data with respect to quality and completeness of the data. Variation in data completeness and data validation between countries needs to be improved for useful international comparison of outcomes.

International Variations in Infrainguinal Bypass Surgery – A VASCUNET Report

ObjectivesTo compare practice in lower limb bypass surgery in nine countries. DesignA prospective study amalgamating and analysing data from national and regional vascular registries. MethodsA table of data fields and definitions was agreed by all member countries of the Vascunet Collaboration. Data from January 2005 to December 2009 was submitted to a central database. Results32,084 cases of infrainguinal bypass (IIB) in nine countries were analysed. Procedures per 100,000 population varied between 2.3 in the UK and 24.6 in Finland. The proportion of women varied from 25% to 43.5%. The median age for all countries was 70 for men and 76 for women. Hungary treated the youngest patients. IIB was performed for claudication for between 15.7% and 40.8% of all procedures. Vein grafts were used in patients operated on for claudication (52.9%), for rest pain (66.7%) and tissue loss (74.1%). Italy had the highest use of synthetic grafts. Among claudicants 45% of bypasses were performed to the below knee popliteal artery or more distally. Graft patency at 30 days varied between 86% and 99%. ConclusionsSignificant variations in practice between countries were demonstrated. These results should be interpreted alongside the known limitations of such registry data with respect to quality and completeness of the data. Variation in data completeness and data validation between countries needs to be improved for useful international comparison of outcomes.

Midterm Results of Autologous Saphenous Vein and ePTFE Pre-Cuffed Bypass Surgery in Peripheral Arterial Occlusive Disease

The graft of choice in lower limb bypass surgery is the autologous saphenous vein (ASV). However, a prosthetic graft is needed in the absence of an ASV. In such situations, we used an expanded polytetrafluoroethylene (ePTFE) pre-cuffed Dynaflo graft as supragenicular bypass or Distaflo graft as infragenicular or femorocrural bypass. In respect to the expanding possibilities of percutaneous transluminal angioplasty (PTA), the indication for bypass surgery moved toward patients with advanced stages of peripheral arterial occlusive disease. For this reason, this study analyzed the current performances of these ePTFE grafts and ASV grafts with special attention to limb salvage. In a retrospective study all patients who underwent peripheral bypass surgery between 2004 and 2008 were included. Kaplan-Meier curves were used to express primary patency, secondary patency, and limb salvage rates at 1 and 3 years. Log-rank tests were performed to compare graft types. A total of 272 grafts (ePTFE/ASV: 110/162) were performed in lower limb bypass surgery. The mean follow-up was 20.3 months. The secondary 3-year patency rates were for (n=78) supragenicular grafts (ePTFE/ASV: 45%/94%)*, for (n=124) infragenicular grafts (24%/74%), and 70 for femorocrural grafts (26%/52%). Limb salvage after 3 years was 59% in the ePTFE group versus 78% in the ASV group (P < .05). In the current population of vascular patients where no PTA is possible and a peripheral bypass is necessary, the ASV remains the graft of first choice. However, the pre-cuffed ePTFE graft is a good alternative, especially in cases of critical limb ischemia, in respect to an acceptable limb salvage rate.

Outcome of Lower Limb Distal Bypass in Afro-Caribbean Populations

There is little data on outcome following lower limb bypass surgery in ethnic minorities in the United Kingdom. We looked at the results of distal bypass surgery in Afro-Caribbeans (AFCs) and compared it to caucasians (CAs). Patients undergoing distal bypass between 2004 and 2009 were analyzed. Life table analyses and log rank were used to compare graft patency and amputation-free survival. A total of 86 CA and 39 AFC patients, with a median age of 78 years and 73 years, respectively (P = .01), underwent bypass. There were more women in AFC groups (41.1%) compared to CA group (19.2%, P = .01). Tissue loss as indication for surgery was more in AFC than in CA group (92.3% vs73.9%, P = .03). Primary, primary-assisted and secondary patency rates, and amputation-free survival at 12 months for AFCs compared to CAs (51.3 vs 44.6; 85.2 vs 80.9; 91.2 vs 84.4; and 84.9 vs 75.1). Graft patency after lower limb distal revascularization in AFCs is comparable to CAs.

Great Saphenous Vein Harvesting: A Systematic Review and Meta-Analysis of Open Versus Endoscopic Techniques

The great saphenous vein is frequently harvested for use as a conduit in lower limb bypass surgery. A number of papers advocate the use of an endoscopic technique rather than a traditional open technique to minimize the associated morbidity. We undertook a systematic review and meta-analysis to compare morbidity associated with these 2 techniques. Medline, PubMed, and secondary referencing identified 16 randomized control trials comparing these 2 methods of harvesting. Primary outcome measures were infection, hematoma, and wound dehiscence and pooled odds ratios (POR) were calculated using a random effects model. Sixteen trials (3689 patients) were identified. Overall complications (POR 7.03), infection (POR 8.08), and wound dehiscence (POR 8.23) were all significantly more common in the open harvesting group compared to the endoscopic group. Endoscopic techniques have a role in vein harvesting but are operator dependent and therefore are only a preferable modality compared to open harvesting methods in experienced hands. More research is required to establish whether long-term patency rates are comparable for the 2 techniques.

VS05 THE ANZSVS BI‐NATIONAL AUDIT

The overwhelming vote by the ANZSVS membership in favour of a change in its constitution to incorporate mandatory society endorsed audit means that it will be necessary for members to comply with the audit to maintain membership of the ANZSVS. Loss of membership of the ANZSVS is likely to have repercussions with regard to accreditation for diagnostic imaging (vascular ultrasound and angiography) and, in that a “vascular specific” CPD is likely to be endorsed there would be repercussions for recertification as a fellow of the Royal Australasian College of Surgeons. With the seemingly inexorable march on the part of the government to national registration there will therefore be repercussions regarding registration as a medical practitioner and the right to practice medicine anywhere in Australia. The Audit is now recognised by the RACS Surgical Audit Committee as an approved audit in the RACS CPD Program. This is an audit of individual's vascular surgical practice. The activities involved in administering the audit are indemnified by the College's Professional Indemnity Insurance Insurer i.e. CGU. The ANZSVS Bi‐National Audit has been granted Qualified Privilege by the DoHA as an extension of the previously granted privilege for MVSA thus obviating the need for a new application. Mr Barry Beiles (FRACS) who developed the acclaimed Melbourne Vascular Surgeons Audit (MVSA) has now developed a focused ANZSVS Audit covering major procedures such as aortic surgery (both open and endoluminal), carotid surgery (both open and endoluminal) and lower limb bypass surgery.

Preliminary experience with denaturated ovine collagen vascular prosthesis (Omniflow II) in lower limb bypass surgery

Preliminary experience with denaturated ovine collagen vascular prosthesis (Omniflow II) in lower limb bypass surgery

Tissue engineering of a hybrid bypass graft for coronary and lower limb bypass surgery

Tissue-engineered blood vessels have largely relied on inelastic scaffolds or biological solutions with uncertain long-term in vivo durability. In this report we present for the first time a hybrid tissue-engineered bypass graft consisting of an elastic scaffold of compliant poly(carbonate-urea)urethane (CPU), incorporated with human smooth muscle cells (SMCs) and endothelial cells (ECs) from the same human source. Human vascular SMCs and ECs were extracted from umbilical cord vessels. The effect of shear stress preconditioning on cell retention on the hybrid bypass graft was investigated under pulsatile arterial flow conditions. Retention of ECs seeded onto CPU precoated with SMCs was significantly improved by a period of shear stress preconditioning, especially when the stress incrementally increased. This is probably because the mechanical stimuli orient cells and increase the release of matrix proteins and attachment factors. The stage is now set for developing a hybrid graft for in vivo studies.

Review of an article: Badger S, Soong C, O’Donnell M, Boreman C, McGuigan K. Benefits of a supervised exercise program after lower limb bypass surgery. Vasc Endovascular Surg 2007;41(1):27-32

Review of an article: Badger S, Soong C, O’Donnell M, Boreman C, McGuigan K. Benefits of a supervised exercise program after lower limb bypass surgery. Vasc Endovascular Surg 2007;41(1):27-32

Arm Vein as a Last Autogenous Option for Infrainguinal Bypass Surgery: It is Worth the Effort

Considerable evidence exists for the use of arm vein conduit in lower limb bypass surgery. The use of arm vein in preference to synthetic conduit as a last autogenous option was assessed for patency and limb salvage outcomes. A prospective database was interrogated and checked against TQEH operating theatre database to detect all infrainguinal arm vein bypasses performed between 1997 and 2005. Patency, limb salvage and survival data for 37 arm vein bypasses was calculated using the Kaplan-Meier survival estimate method. There were no perioperative deaths. 30 day patency rates were 89% primary, 95% secondary and 95% limb salvage. 12 month patency rates were 56% primary, 79% secondary and 91% limb salvage. 5 year patency rates were 37% primary, 76% secondary and 91% limb salvage. There was no significant patency advantage for primary vs. "redo" grafts (p=0.54), single vessel vs. spliced conduits (p=0.33) or popliteal vs tibial outflow (p=0.80). Patient survival rate was 92% and 65% at 1 and 5 years respectively. Lower limb bypasses using arm vein can be performed with favourable patency and limb salvage compared to synthetic conduits. However, secondary interventions are frequently required to maintain patency. We recommend a vigilant surveillance program for early identification of patency threatening disease.

Cellular Engineering of Conduits for Coronary and Lower Limb Bypass Surgery: Role of Cell Attachment Peptides and Pre-conditioning in Optimising Smooth Muscle Cells (SMC) Adherence to Compliant Poly(carbonate–urea)urethane (MyoLink™) Scaffolds

Objective. We are developing a hybrid arterial bypass graft of compliant poly(carbonate–urea)urethane (MyoLink™), endothelial and smooth muscle cells (SMCs). To enhance adhesion of SMCs we assessed various attachment factors and the effect of pre-conditioning on cell retention.Methods. MyoLink segments were coated with either RGD, superfibronectin, fibronectin, fibronectin-like engineered polymer protein (FEPP), FEPP plus or type 1 collagen overnight. 111Indium-radiolabelled SMCs were placed onto MyoLink segments for 48 h before being aspirated, then lavaged off. All grafts, aspirates and lavages were counted in a gamma counter. SMC viability on the MyoLink segments was also assessed for viability using the Alamar blue redox assay. Separately, MyoLink grafts lined with radiolabelled SMCs were divided into a pre-conditioned group, exposed to subarterial pulsatile flow whilst another group were held in static culture. After 1-week, grafts were exposed to arterial pulsatile flow whilst radioactivity was assessed using a gamma camera.Results. Only FEPP plus significantly enhanced SMC attachment: mean of 32±6% cell attachment compared to 21±5% for uncoated control. Cell viability was enhanced by all attachment factors except fibronectin. Pre-conditioning was shown to significantly enhance the retention of SMCs onto the MyoLink once exposed to pulsatile arterial flow: the final attachment was 57±7% for the static and 76±7% for the pre-conditioned group.Conclusions. FEPP plus enhances SMC attachment to MyoLink. We believe this is because of its repeating sequences of RGD and its positive charge. Pre-conditioning enhances the retention of SMCs to MyoLink once exposed to pulsatile arterial flow.

The use of animal models in developing the discipline of cardiovascular tissue engineering: a review

Cardiovascular disease remains one of the major causes of death and disability in the Western world. Tissue engineering offers the prospect of being able to meet the demand for replacement of heart valves, vessels for coronary and lower limb bypass surgery and the generation of cardiac tissue for addition to the diseased heart. In order to test prospective tissue-engineered devices, these constructs must first be proven in animal models before receiving CE marking or FDA approval for a clinical trial. The choice of animal depends on the nature of the tissue-engineered construct being tested. Factors that need to be considered include technical requirements of implanting the construct, availability of the animal, cost and ethical considerations. In this paper, we review the history of animal studies in cardiovascular tissue engineering and the uses of animal tissue as sources for tissue engineering.

Second Best Medical Therapy

Background : best medical therapy (BMT) provides patients with peripheral arterial disease (PAD) substantial protection against future vascular events. Objective : to determine the quality of BMT received by PAD patients in this vascular surgery unit. Methods : retrospective case-note review of 50 consecutive patients in each of the following groups: intermittent claudication (out-patients), symptomatic carotid artery disease (out-patients), lower limb angioplasty, lower limb bypass surgery, carotid endarterectomy. Results : overall BMT use was poor. Fifteen percent of smokers had assistance with smoking cessation noted. Seventy-eight percent of patients were taking an antiplatelet agent, 38% cholesterol-lowering medication and 51% antihypertensive medication. Fifty-three percent of patients had a cholesterol measurement, 50% of out-patients had a blood pressure measurement and 53% of non-diabetics had a random blood glucose performed. Sixteen of the patients with lower limb disease were given advice about exercise. Patients with a history of coronary artery disease were more likely to be taking cholesterol lowering, or antihypertensive medication. Conclusions : BMT is poorly used in patients with PAD, which will result in an excess of cardiovascular morbidity and mortality. Strategies need to be developed to increase the use of BMT in our patients.

Venous Allografts for Infrainguinal Vascular Bypass

Between 1978 and 1993, 107 patients received venous allografts for infrainguinal revascularization because autogenous material was unavailable. These operations comprised 7.4% of 1442 reversed vein bypass procedures performed during the same period. Alloveins were harvested during varicose vein stripping and stored up to 10 days in saline solution containing heparin and antibiotics. Veins with or without minimal degenerative changes were used and when necessary segments were sutured end-to-end to obtain a convenient length. The patients comprised 95 men and 12 women of age range 44–87 years. All operations were performed for limb salvage (rest pain and gangrene); 40 femoropopliteal and 67 femorocrural bypasses were performed; 66 were primary reconstructions and 41 secondary reconstructions. The operative mortality rate was 3.7%. Early thrombosis occurred in 18 patients (16.8%), nine of whom were successfully reoperated upon. The cumulative patency rates for all bypass operations was 82.9%, 38.7% and 21.3% at 30 days, 3 and 5 years, respectively, the limb salvage rates being 84.8%, 48.0% and 29.2%, respectively. Allografts may have a place in lower-limb bypass surgery in the absence of veins, polytetrafluoroethylene or human umbilical vein.

Venous allografts for infrainguinal vascular bypass

Between 1978 and 1993, 107 patients received venous allografts for infrainguinal revascularization because autogenous material was unavailable. These operations comprised 7.4% of 1442 reversed vein bypass procedures performed during the same period. Alloveins were harvested during varicose vein stripping and stored up to 10 days in saline solution containing heparin and antibiotics. Veins with or without minimal degenerative changes were used and when necessary segments were sutured end-to-end to obtain a convenient length. The patients comprised 95 men and 12 women of age range 44–87 years. All operations were performed for limb salvage (rest pain and gangrene); 40 femoropopliteal and 67 femorocrural bypasses were performed; 66 were primary reconstructions and 41 secondary reconstructions. The operative mortality rate was 3.7%. Early thrombosis occurred in 18 patients (16.8%), nine of whom were successfully reoperated upon. The cumulative patency rates for all bypass operations was 82.9%, 38.7% and 21.3% at 30 days, 3 and 5 years, respectively, the limb salvage rates being 84.8%, 48.0% and 29.2%, respectively. Allografts may have a place in lower-limb bypass surgery in the absence of veins, polytetrafluoroethylene or human umbilical vein. © 1997 The International Society for Cardiovascular Surgery.