Infrainguinal Vein Bypass Grafts Research Articles

Feasibility of Percutaneous Ultrasound Guided Intervention with Direct Access in Failing Infrainguinal Vein Bypass Grafts

Patients with infrainguinal venous bypass grafts are at risk of graft stenosis leading to thrombosis and failure of the graft conduit. When primary assisted reintervention is needed, a common first choice of treatment is percutaneous angioplasty using fluoroscopy and digital subtraction angiography (DSA). We investigated whether percutaneous ultrasound-guided intervention (PUSGI) is feasible for such endovascular reinterventions. In this retrospective observational study (feasibility study), we included patients with ultrasound evidence of significant stenosis in below-the-knee vein grafts in the lower extremities. Inclusion period was 18 months. Reinterventions were disrupted by performing PUSGI in between traditional DSA. Perioperative success was defined as no sign of residual stenosis, stenosis at the access point in the vein, or need for further fluoroscopy guided intervention. Patient follow-up was conducted 6weeks after the intervention. Patency of the procedure was defined as no disease recurrence or signs of ultrasonographic restenosis at follow-up. PUSGI was performed in 17 patients referred for reintervention with imminent failing grafts (12 men, 5 women, age range 52-82years). PUSGI alone was performed successfully in 10 out of 17 patients (59%). The remaining 7 patients underwent successful revascularization with PUSGI in combination with DSA-guided angioplasty. Periprocedural complications occurred in 4 patients. Two of 17 patients had occluded grafts at 6weeks of follow-up. No PUSGI access site stenoses in grafts were observed. Percutaneous ultrasound-guided reintervention in peripheral vein bypass disease is feasible for selected patients. The study provides insight to qualitative criteria of eligibility for PUSGI in such reinterventions with direct conduit access.

Smartphone-Mounted Infrared Thermography Camera to Assess Success of Open Infrainguinal Revascularisation

Introduction - Early thrombosis occurs in around 7% of infrainguinal vein bypass grafts(1). Recognition of this complication and prompt reintervention may salvage the graft and the limb. Peri-operative monitoring of graft patency is often dependent on nursing and other non specialist staff. In the presence of calf artery disease and poor runoff peripheral pulses are often impalpable and assessment of graft patency may be difficult. Frequently graft thrombosis may remain unrecognised. The aim of this study was to assess the role of a smartphone-mounted infrared thermography (IRT) camera to monitor bypass graft patency in the early postoperative period. Methods - 10 consecutive patients undergoing infrainguinal vein bypass surgery for critical ischaemia at a tertiary referral vascular unit were recruited. Thermography images of the soles of both feet were taken using a smartphone-mounted IR camera on the morning before surgery and the morning after surgery. The images taken were immediately available on the smartphone and mean temperature of four different areas of the sole based on angiosome distribution (medial heel, lateral heel, medial forefoot, lateral forefoot) and the pulps of the hallux and the third toe (when present or adjacent toe when amputated) were measured using the smartphone application. The relative change in temperature differences between the two feet between the pre and postoperative images in the six areas was then calculated. All grafts underwent duplex scanning to assess for patency in the postoperative period. Results - n 9 out of 10 cases there was a significant increase in relative temperature difference between the two feet between the pre and post operative images in all areas with the revascularised foot being warmer (mean relative change in temperature +4.47 degrees celsius). The biggest positive shifts in relative temperature occurred in the lateral forefoot and the big toe (5.6; STD 3.02; 6.23 STD 3.46). In one case the temperature difference between the two feet showed a negative shift with the treated foot being cooler (mean relative change in temperature -6.66 degrees celsius). On duplex scanning the 9 cases with a positive shift in relative temperature difference had a patent graft while the case with a negative shift had an occluded graft. This was successfully thrombectomised and the distal anastomoses revised. Visualisation of the colour palette representation of the temperature pattern of the foot alone was sufficient to identify a positive shift in the 9 cases with a patent graft as well as a negative shift in the one occluded graft. (See image) Conclusion - A smartphone mounted infrared thermography camera provides a quick, simple and relatively cheap technique for effective monitoring of infrainguinal bypass graft patency in the early postoperative period. The colour pattern representation of the temperature pattern of the foot allows non specialist staff to easily identify significant negative shifts in temperature triggering specialist assessment of graft patency.

An omnidirectional visualization model of personalized gene regulatory networks

Gene regulatory networks (GRNs) have been widely used as a fundamental tool to reveal the genomic mechanisms that underlie the individual’s response to environmental and developmental cues. Standard approaches infer GRNs as holistic graphs of gene co-expression, but such graphs cannot quantify how gene–gene interactions vary among individuals and how they alter structurally across spatiotemporal gradients. Here, we develop a general framework for inferring informative, dynamic, omnidirectional, and personalized networks (idopNetworks) from routine transcriptional experiments. This framework is constructed by a system of quasi-dynamic ordinary differential equations (qdODEs) derived from the combination of ecological and evolutionary theories. We reconstruct idopNetworks using genomic data from a surgical experiment and illustrate how network structure is associated with surgical response to infrainguinal vein bypass grafting and the outcome of grafting. idopNetworks may shed light on genotype–phenotype relationships and provide valuable information for personalized medicine.

Heterogeneous and dynamic lumen remodeling of the entire infrainguinal vein bypass grafts in patients

ObjectiveTo examine the regional variation and temporal change in lumen size along the entire autogenous vein bypass graft used for treating arterial occlusive disease in lower extremity and to explore the factors associated with graft expansive or constrictive remodeling. MethodsPatients were prospectively scanned using contrast-enhanced computed tomography at 1 week and 1, 6, and 12 months postoperatively to obtain lumen cross-sectional areas at 1-mm intervals along the entire grafts. Graft lumen remodeling characteristics and the associated demographic and clinical factors were examined. ResultsFifty-six patients with at least two consecutive computed tomography scans were analyzed. Patients with a composite or longer graft, or with diabetes, had a larger lumen cross-sectional area variation along the graft. The mean lumen cross-sectional areas of all the grafts demonstrated no significant changes through 12 months. However, individually, graft remodeling was time dependent and there was a more dramatic change in lumen cross-sectional area within the first postoperative month. At 12 months, a near equal distribution between expansive and constrictive grafts existed. A negative relation between the initial lumen diameters and the subsequent lumen diameter changes was observed. Eleven grafts failed within 12 months; failed and patent grafts had similar mean lumen cross-sectional areas at all four time points, but failed grafts had a larger maximal local cross-sectional area reduction from 1 week to 1 month (58.0 ± 6.7% vs 38.1 ± 3.1%, mean ± standard error of the mean, failed vs patent, P = .004). Black patients had a smaller mean lumen cross-sectional area than white patients at all four time points and also had a higher early percent mean area reduction (−20.5 ± 6.3% vs −1.0 ± 3.7%, black vs white, P = .018). Cilostazol use was associated with early expansive graft remodeling. ConclusionsVein grafts remodel heterogeneously and dynamically. Remodeling is associated with initial graft lumen size, race, and cilostazol use. It is found that remodeling that produces some critical minimum area or maximal percent reduction during the first postoperative month may predispose to vein graft failure. These findings offer insight into further investigation to examine the underlying mechanisms and opportunities to improve graft remodeling and durability.

Hyperacute Monocyte Gene Response Patterns Are Associated With Lower Extremity Vein Bypass Graft Failure.

Despite being the definitive treatment for lower extremity peripheral arterial disease, vein bypass grafts fail in half of all cases. Early repair mechanisms after implantation, governed largely by the immune environment, contribute significantly to long-term outcomes. The current study investigates the early response patterns of circulating monocytes as a determinant of graft outcome. In 48 patients undergoing infrainguinal vein bypass grafting, the transcriptomes of circulating monocytes were analyzed preoperatively and at 1, 7, and 28 days post-operation. Dynamic clustering algorithms identified 50 independent gene response patterns. Three clusters (64 genes) were differentially expressed, with a hyperacute response pattern defining those patients with failed versus patent grafts 12 months post-operation. A second independent data set, comprised of 96 patients subjected to major trauma, confirmed the value of these 64 genes in predicting an uncomplicated versus complicated recovery. Causal network analysis identified 8 upstream elements that regulate these mediator genes, and Bayesian analysis with a priori knowledge of the biological interactions was integrated to create a functional network describing the relationships among the regulatory elements and downstream mediator genes. Linear models predicted the removal of either STAT3 (signal transducer and activator of transcription 3) or MYD88 (myeloid differentiation primary response 88) to shift mediator gene expression levels toward those seen in successful grafts. A novel combination of dynamic gene clustering, linear models, and Bayesian network analysis has identified a core set of regulatory genes whose manipulations could migrate vein grafts toward a more favorable remodeling phenotype.

Reversed Vein Lower Extremity Bypass Shows Trends Toward Better Overall Patency With Significantly Fewer Amputations Compared To Non-Reversed Configuration

Multiple configurations exist for construction of infra-inguinal vein bypass grafts, including reversed (RV) , in-situ and non-reversed transposed (NRV) vein grafts. Potential exists for technique to influence graft success. Our study aimed to define the relationship between vein graft orientation and patient outcomes, including patency, re-interventions and amputation rates.

Follow-up and surveillance of vein grafts: when and how to intervene to prevent complications.

Despite advances in endovascular strategies, surgical infrainguinal lower limb revascularization remains the gold standard treatment for critical lower limb ischemia and disabling claudication. Maintaining patency of infrainguinal vein bypass grafts has been a challenging task for vascular surgeons as they are prone to developing stenoses which may precipitate failure of the bypass. Duplex ultrasound scanning has evolved as the investigation of choice to identify vein graft lesions but graft surveillance programs using this technique remain controversial. The rationale for graft surveillance is that intervention in a patent but failing graft results in improved long-term patency and limb salvage rates compared to rescue of an occluded graft. The six-week postoperative Duplex ultrasound scan is important in identifying flow abnormalities that can predict the natural history of a vein graft and the outlook for the limb in the medium term. There are multiple factors influencing vein graft failure, which means guidelines should be flexible in terms of when and which type of intervention to the graft is optimum. Patency and durability favour open surgical revision over endovascular intervention but this must be counter balanced by the increased morbidity associated with surgical revision.

Stenting as a bail-out option after failed percutaneous transluminal angioplasty in infrainguinal vein bypass grafts.

To study the safety and efficacy of bare and covered stents in infrainguinal vein grafts after failure of PTA for treating graft stenoses. An analysis of a prospective database of all patients who underwent stenting of infrainguinal vein bypass grafts at this institution between 1 January 2008 and 31 December 2012 was carried out. The main outcome considered was primary patency, which was reported at 1, 6 and 12 months. A total of 18 patients with a mean age of 73 years (range: 56 to 86) were included. The indications for stent placement were significant recoil (7, 39%), graft rupture (6, 33%), residual vein cusps (3, 17%) and aneurysmal degeneration (2, 11%). There was a high overall technical success rate of 94% (17/18) and arrest of haemorrhage was achieved in all cases of graft rupture. The primary patency at 1, 6 and 12 months was 89%, 71% and 59%, respectively. The use of bare and covered stents in infrainguinal vein grafts appears safe and effective. They are an excellent bail-out option for the treatment of graft rupture and give acceptable short-term results.

Infrainguinal Vein Graft Stenoses: Long-Term Outcomes of Graft Angioplasty

Graft angioplasty combines the durability and ability of surgical bypasses to treat long arterial occlusions with the minimally invasive nature of endovascular procedures. The purpose of this study was to evaluate the efficacy of single and repeated graft angioplasty in revising failing infrainguinal vein bypass grafts and to determine predictors of medium- and long-term freedom from revision after graft angioplasty. This was a retrospective analysis from a prospectively maintained database. Consecutive endovascular revisions of graft-threatening lesions identified by duplex ultrasound surveillance were reviewed from 2003 to 2010. Patients were followed up until death, major amputation, or the end of follow-up, with the data last updated on January 1, 2013. 178 graft angioplasty procedures performed in 114 bypass grafts in 103 limbs from 98 patients were studied. At 5 years, freedom from revision was 22.6%, graft survival was 45.8%, amputation-free survival was 57.9%, and patient survival was 64.9%. Analysis of repeated angioplasties found no evidence that effectiveness diminishes significantly with the number of previous angioplasties performed (p=.892). Higher Rutherford Grade of ischemia and longer time interval from index surgery to first angioplasty were significant positive predictors of medium- and long-term patency. Percutaneous transluminal angioplasty of infrainguinal vein grafts is safe and effective in the treatment of failing grafts identified by duplex surveillance. Graft angioplasties do not lose effectiveness when repeated and have shown cumulative benefit in prolonging graft survival. Treatment of claudicants and time interval from graft implantation of more than 6monthsat the time of first angioplasty are positive predictors of at least medium-term patency after graft angioplasty.

Balloon Angioplasty as the Primary Treatment for Failing Infrainguinal Vein Grafts

Background: We sought to evaluate the role of balloon angioplasty as the primary modality in the management of vein graft stenoses. Methods: Patients who underwent infrainguinal vein graft bypass from January 2002 to December 2007 were enrolled into a surveillance program. Grafts which developed critical stenoses were identified and underwent urgent angiography with a view to angioplasty of the stenotic lesion. Lesions which were deemed unsuitable for angioplasty underwent urgent surgical repair. Results: Four hundred and eleven grafts were followed up for a median of 19 months (range: 2–61). Ninety-six grafts (22.6%) developed critical stenosis. Twelve grafts occluded prior to repair and one was not intervened upon electively. Eight grafts underwent primary surgical repair. Seventy-six grafts underwent 99 endovascular procedures. Technical success was achieved in 60 grafts (78.9%). Of the grafts in which technical success had not been achieved, eight underwent repeat angioplasty and three were surgically repaired. Twenty-four grafts underwent repeat angioplasty for re-stenosis with a technical success rate of 71%. No difference was observed in graft patency (P = 0.08) or amputation rates (P = 0.32) between the grafts requiring intervention to maintain patency, and grafts which did not. Smoking [OR: 2.61 (95% CI: 1.51–4.53), (P = 0.006)], diabetes [OR: 2.55 (95% CI: 1.49–4.35), (P = 0.006)], renal failure [OR: 1.89 (95% CI: 1.19–3.38), (P = 0.040)] and recurrent stenosis [OR: 3.22 (95% CI: 1.63–4.69), (P < 0.001)] were risk factors for graft occlusion. Conclusions: Balloon angioplasty of failing infrainguinal vein bypass grafts is safe and can be performed with an acceptable medium term patency rate, albeit with a significant risk of re-stenosis which can be successfully treated in most patients using repeat endovascular intervention.

Balloon Angioplasty as the Primary Treatment for Failing Infra-inguinal Vein Grafts

Background We sought to evaluate the role of balloon angioplasty as the primary modality in the management of vein graft stenoses. Methods Patients who underwent infrainguinal vein graft bypass from January 2002 to December 2007 were enrolled into a surveillance program. Grafts which developed critical stenoses were identified and underwent urgent angiography with a view to angioplasty of the stenotic lesion. Lesions which were deemed unsuitable for angioplasty underwent urgent surgical repair. Results Four hundred and eleven grafts were followed up for a median of 19 months (range: 2–61). Ninety-six grafts (22.6%) developed critical stenosis. Twelve grafts occluded prior to repair and one was not intervened upon electively. Eight grafts underwent primary surgical repair. Seventy-six grafts underwent 99 endovascular procedures. Technical success was achieved in 60 grafts (78.9%). Of the grafts in which technical success had not been achieved, eight underwent repeat angioplasty and three were surgically repaired. Twenty-four grafts underwent repeat angioplasty for re-stenosis with a technical success rate of 71%. No difference was observed in graft patency ( P = 0.08) or amputation rates ( P = 0.32) between the grafts requiring intervention to maintain patency, and grafts which did not. Smoking [OR: 2.61 (95% CI: 1.51–4.53), ( P = 0.006)], diabetes [OR: 2.55 (95% CI: 1.49–4.35), ( P = 0.006)], renal failure [OR: 1.89 (95% CI: 1.19–3.38), ( P = 0.040)] and recurrent stenosis [OR: 3.22 (95% CI: 1.63–4.69), ( P < 0.001)] were risk factors for graft occlusion. Conclusions Balloon angioplasty of failing infrainguinal vein bypass grafts is safe and can be performed with an acceptable medium term patency rate, albeit with a significant risk of re-stenosis which can be successfully treated in most patients using repeat endovascular intervention.

Predictors of failure after angioplasty of infrainguinal vein bypass grafts

Percutaneous transluminal angioplasty (PTA) has had an expanding role as primary therapy for vein graft stenosis with variable results. The aim of this study is to identify patient and graft characteristics predictive of failure after PTA of infrainguinal vein grafts. Retrospective review from Jan 2004 to Mar 2007 of patients undergoing angioplasty for failing grafts. Demographics, comorbidities, procedural data, and follow-up information were recorded. PTA failure was defined as first significant event including restenosis by duplex scan (>3.5 x velocity ratio), occlusion, redo-PTA, surgical revision, or amputation. Descriptive, logistic regression and life-table analyses were performed. Eighty-seven grafts in 79 patients underwent PTA. Mean age was 70 years (median 70; range, 39-89 years), 71% were male and 52% were symptomatic (40% with limb-threat). Mean follow-up was 17 months (median 17.4; range, 0.03-39.8 months). Freedom from PTA failure was 58% (standard error [SE] 0.0574) at 12 months. Predictors of PTA failure by multivariate analysis were: time from bypass <3 months (hazard ratio [HR] 5.8; 95% confidence interval [CI] 1.91-18.0; P = .002), stenosis length >2 cm (HR 2.7; 95% CI 1.33-5.83; P = .007) and multiple stenoses (HR 2.5; 95% CI 1.29-5.1; P = .007). PTA patency for grafts with favorable lesions (single, less than 2 cm lesions in grafts older than 3 months) was 71% vs 35% for unfavorable lesions at 12 months. Limb-salvage was 95% and 90% and overall survival was 92% and 81% at 12 and 24 months, respectively. PTA of failing infrainguinal vein grafts is a reasonable primary therapy for favorable lesions. Early graft stenosis, long, and multiple stenoses are markers for procedural failure and are better served with surgical revision.

Infrainguinal vein graft stenosis: Cutting balloon angioplasty as the first-line treatment of choice

The optimal treatment for hemodynamically significant infrainguinal vein bypass graft stenosis is not known. This study compares three options as first choice for the revision of failing infrainguinal vein grafts: cutting balloon angioplasty (CBA), standard percutaneous transluminal balloon angioplasty (PTA), and open surgical revision (OS). Infrainguinal vein bypass graft lesions treated in a single institution during a 12-year period were evaluated. Of these, 161 lesions in 124 infrainguinal bypasses (101 patients) were treated with OS (n = 42), PTA (n = 57), or CBA (n = 62). The initial indication for the bypass in these patients was limb salvage in 73% and claudication in 27%. The primary outcome of interest was the development of vein graft occlusion or significant stenosis (>or=70%) as detected by surveillance duplex ultrasound scanning or arteriography some time after repair. The stenosis-free patency rates at 48 months for OS, CBA, and PTA were 74%, 62%, and 34%, respectively. PTA was associated with an increased risk of treatment failure compared with both OS (hazard ratio [HR], 3.9; P < .0001) and CBA (HR, 3.1; P < .0001). There was no significant difference between OS and CBA (HR, 1.3 for CBA vs OS, P = .6). Pseudoaneurysms developed in two CBA patients. One ruptured and required interposition graft, and one was monitored. Cutting balloon angioplasty is a reasonable, initial treatment for infrainguinal vein graft stenosis in most patients. It is a safe, minimally invasive, outpatient procedure with patency rates that are comparable to OS and superior to PTA.

Surgical and endovascular revision of infrainguinal vein bypass grafts: Analysis of midterm outcomes from the PREVENT III trial

Data supporting the utility of percutaneous treatment to maintain vein graft patency have been limited to a collection of single-institution, retrospective analyses. Using the prospective, multi-institutional PREVENT III database, we sought to define the outcomes for endovascular vs surgical vein bypass graft revision and to define predictors for the success or failure of these interventions. A nested cohort study of 1404 patients in the PREVENT III trial who underwent infrainguinal vein bypass grafting for critical limb ischemia was performed to identify those patients who underwent either open surgical or endovascular graft revision. All patients in PREVENT III were followed up for 1 year from the initial bypass operation. The following were modeled as end points from the time of the initial open surgical or endovascular revision: freedom from graft reintervention, occlusion, amputation, and death. A total of 156 open surgical and 134 endovascular reinterventions were performed, with a mean follow-up after revision of 193 and 151 days, respectively. Although the demographics for each group were similar, the choice of repair was influenced by the interval between the index graft placement and the initial revision, with a high percentage of the early graft revisions treated with an open surgical procedure (0-1 months: 84% open surgical vs 16% endovascular; P < .001). The primary end point (ie, failure resulting in repeat graft revision, graft occlusion, or major amputation) was reached in 30.2% of the endovascular and 26.2% of the open surgical individuals, with significant improvements in the durability of graft revisions noted in the open surgical group (12-month amputation-/revision-free survival of 75% for the open surgical and 56% for the endovascular group; hazard ratio, 2.2; 95% confidence interval, 0.92-5.26; P = .043). Furthermore, subgroup analysis revealed this benefit to be most profound within the subset of thrombosed grafts undergoing salvage (P = .006). For revisions performed to treat graft stenosis, early outcomes were similar, with a trend favoring the open surgical group developing beyond 6 months. Although 80% of open surgical and 64% of endovascular-revised grafts required no further intervention, endovascular revisions necessitated significantly more reinterventions to maintain patency. The mean hospital lengths of stay (open surgical, 2.1 days; endovascular, 1.7 days) and quality of life at completion of the study (VascuQoL: open surgical, 4.72; endovascular, 4.76) were similar between the groups. Open surgical revision of infrainguinal vein grafts provides an increased freedom from further reinterventions or major amputation, but early success rates for endovascular procedures were similar, particularly for nonoccluded grafts. With time, endovascular revisions necessitate an increasing number of reinterventions and manifest higher rates of failure.

Cutting balloon angioplasty of autogenous infrainguinal bypasses: Short-term safety and efficacy

This study evaluated the safety and efficacy of cutting balloon angioplasty in the treatment of infrainguinal vein bypass graft stenosis. Data from a prospective database, supplemented by chart review, were obtained on all patients who underwent cutting balloon angioplasty of lower extremity vein bypass grafts at a single institution during a 4-year period. Noninvasive duplex ultrasound imaging of grafts, along with measurement of ankle-brachial indices and digital pressures, was performed on all patients before and after treatment with the cutting balloon. Efficacy of cutting balloon angioplasty and procedural complications were analyzed. Data from noninvasive vascular testing were compared using the two-tailed paired Student t test. Patency rates were calculated using the Kaplan-Meier method. Differences in patency rates were compared using the log-rank test. From July 2002 to February 2006, 109 cutting balloon angioplasties were performed on 70 bypasses in 61 patients. There were 12 complications in 109 procedures (11%), only one of which required immediate operative intervention. Initial technical success was 96%. Noninvasive vascular testing indicators significantly improved immediately after intervention: peak systolic graft velocity decreased from 360 +/- 158 cm/s to 143 +/- 67 cm/s (P < .001), ankle-brachial index improved from 0.55 +/- 0.3 to 0.85 +/- 0.2 (P < .001), and digital pressure increased from 31 +/- 30 mm Hg to 62 +/- 32 mm Hg (P < .001). Patency rates at 6 months according to the Kaplan-Meier method were primary patency, 48% (95% confidence interval [CI], 0.36 to 0.60); assisted primary patency, 72% (95% CI, 0.61 to 0.83); and secondary patency, 99% (95% CI, 0.97 to 1.00). At 6 months, cumulative limb salvage was 94% (95% CI, 0.89 to 1.00). Cutting balloon angioplasty of infrainguinal vein bypass graft stenosis is technically feasible but is associated with a relatively high complication rate and a relatively low short-term patency rate.

Perioperative use of eicosapentaenoic acid and patency of infrainguinal vein bypass: A retrospective chart review

Abstract. A significant proportion of autogenous vein grafts fail in the long term. Currently, there is no treatment to improve graft patency. This study was designed to assess the effectiveness of eicosapentaenoic acid (EPA) to prevent late failure of an autogenous vein graft and other perioperative risk factors affecting long-term patency. A retrospective chart review was performed on grafts of patients who underwent infrainguinal bypass surgery using autogenous vein grafts for peripheral arterial disease in a lower limb. Patients were stratified by the perioperative use of EPA. The EPA group was those patients who administered EPA ≥1 time within 3 months of surgery. The non-EPA group was made up of those patients who did not administer EPA within 3 months of surgery. Primary, assisted primary, and secondary patency rates of the grafts in each group were calculated by the Kaplan-Meier method and compared by the log-rank test. To evaluate the effect of other perioperative risk factors, a Cox proportional hazards analysis was performed. One hundred sixty-one grafts were analyzed from 159 patients who underwent surgery between July 1991 and July 2005. The primary patency rates of the EPA and non-EPA groups were 93% and 86%, 89% and 74%, and 83% and 68% at 1, 3, and 5 years, respectively. In terms of primary patency, the EPA group was significantly better than the non-EPA group (P=0.042). There was no significant difference between the groups in either assisted primary or secondary patency. A Cox proportional hazard analysis found that the minimum graft diameter and perioperative use of EPA were significant factors for primary patency (P=0.002 and P=0.004, respectively). Graft diameter was the only significant factor for assisted primary and secondary patency (P=0.021 and P=0.003, respectively). Although graft diameter was the most important factor for long-term patency of infrainguinal vein bypass grafts, the perioperative use of EPA significantly improved primary patency among these subjects.

Cutting Balloon Angioplasty Versus Standard Balloon Angioplasty for Failing Infra-inguinal Vein Grafts: Comparative Study of Short- and Mid-Term Primary Patency Rates

To evaluate the results of a recent change in practice in our institution using cutting balloon angioplasty instead of standard balloon angioplasty as the primary treatment for failing infra-inguinal vein bypass grafts. In this nonrandomized cohort study with a historical control, failing infra-inguinal vein grafts were identified at duplex surveillance or clinical examination. Patients had confirmatory arteriography and balloon angioplasty at the same attendance. Interventions proximal or distal to the graft itself and prosthetic grafts were not included. Patients were entered into a duplex graft surveillance program. Initial assessment of technical success was duplex or improvement 4-6 weeks after the primary angioplasty. Twenty-seven consecutive patients were treated with standard balloon angioplasty, then 11 consecutive patients were treated with cutting balloon angioplasty. Initial technical success was 74% for the standard balloon versus 82% for the cutting balloon. The primary patency rate at 6 months was 16/26 (62%) for standard balloon angioplasty and 8/10 (80%) for cutting balloon angioplasty (p = 0.44). The primary patency rate at 12 months was 9/25 (36%) for standard balloon angioplasty and 5/10 (50%) for cutting balloon angioplasty (p = 0.47). The use of cutting balloons for primary angioplasty of infra-inguinal vein grafts offers no definite advantage over standard balloon angioplasty in this institution or compared with patency rates after standard balloon angioplasty reported elsewhere. Larger multicenter studies would be required to demonstrate whether there was any real difference between the two techniques.

Infrainguinal Vein Bypass Graft Revision: Factors Affecting Long-term Outcome

Infrainguinal Vein Bypass Graft Revision: Factors Affecting Long-term Outcome

The Distal Zone of the Deep Femoral Artery as the Inflow Site in Femorodistal Bypass Grafting

The distal zone of the deep femoral artery has been used as an inflow site for femorodistal bypass grafts. Eleven such bypass grafts were performed in patients who had critical limb ischemia either to avoid a hostile groin ( n=7) or because of an insufficient length of vein ( n=4). The posteromedial route was used. Two of the 11 grafts had early failure and a third failed at 3 months: redo surgery restored arterial blood flow to the limb in all three patients. The procedure was safe and is a widely applicable, effective alternative that extends the limits of infrainguinal vein bypass grafting.

Guidelines on oral anticoagulation (warfarin): third edition – 2005 update

The British Committee for Standards in Haematology (BCSH) published its third edition of Guidelines on Oral Anticoagulation in 1998 (British Committee for Standards in Haematology, 1998). Most of the recommendations made in 1998 remain unchanged and a fourth edition of the guideline is considered unnecessary at the time of writing (June 2005). However, we draw attention to those areas where new informative data have been published. As in the original guideline, the term ‘oral anticoagulant’ used in this update refers to oral vitamin K antagonists (VKA), such as warfarin. New oral non-VKA are currently being evaluated in clinical trials but are not yet licensed for use in the UK. When these drugs become available new guidance will be issued specifically for the use of those drugs. The guideline group was selected to be representative of UKbased medical experts. The drafting group met and communicated by email. MEDLINE was searched systematically for publications in English from 1998. The writing group convenor (T. Baglin) produced the draft guidelines which were subsequently revised by consensus. The guideline was reviewed by a multidisciplinary sounding board, the BCSH and the British Society for Haematology (BSH) and comments incorporated where appropriate. Criteria used to quote levels and grades of evidence are as in Appendix 3 of the Procedure for Guidelines Commissioned by the BCSH (http://www.bcshguidelines.com/process1.asp#App3). The target audience for this guideline is healthcare professionals involved in the management of patients receiving oral anticoagulant therapy.