Infrainguinal Bypass Procedures Research Articles

Evaluating the Management of Intermittent Claudication before and after Publication of the Society of Vascular Surgery's Appropriate Use Criteria.

In April 2022, the Society for Vascular Surgery (SVS) published the Appropriate Use Criteria (AUC) for the management of intermittent claudication (IC). Our goal was to compare practice patterns before and after publication of the AUC to identify changes. The Vascular Quality Initiative (VQI) peripheral vascular intervention (PVI), and suprainguinal, and infrainguinal bypass registries were analyzed for interventions for IC. Relevant patient and intervention characteristics pre-AUC (2018-2019) and post-AUC (May 2022-December 2023) were compared. Key points of the AUC that are analyzable from the VQI include claudication severity, use of optimal medical therapy (OMT), smoking status, high-risk comorbid conditions (as indicators of operative risk), operative management of complex aortoiliac and femoropopliteal disease (TASC II C/D), common femoral artery (CFA) PVIs, and infrapopliteal procedures. There were 15,892 PVI, 2352 suprainguinal bypass, and 3480 infrainguinal bypass procedures analyzed. Changes consistent with the appropriateness ratings for PVI included more interventions for severe symptoms (72% vs 66.6%, P<.001), improvement in post-operative OMT (83% vs 79.7%, P<.001), fewer patients on dialysis undergoing PVI (2% vs 2.7%, P<.002), and less interventions on complex (TASC II C/D) aortoiliac (6.3% vs 9.5%, P<.001) and femoropopliteal (4.5% vs 5.8%, P <.001) anatomy. No changes were seen in the rates of pre-operative smoking and pre-operative OMT use, interventions on octogenarians, or in the use of extra-anatomic suprainguinal bypass, infrapopliteal bypass, or prosthetic conduit. Inconsistent with appropriateness ratings were more patients with congestive heart failure (15.1% vs 12.8%, P<.001) undergoing PVIs, and more PVIs for CFA (5.2% vs 3.4%, P<.001) and isolated infrapopliteal disease (5.7% vs 3.5%, P<.001). Since the publication of the AUC, there have been improvements with better OMT on discharge, fewer patients with ESRD undergoing interventions, and less endovascular treatment of complex disease. However, further work is needed to improve pre-operative medical optimization in patients with IC undergoing an invasive intervention and decrease the use of endovascular interventions for CFA and infrapopliteal disease, extra-anatomic aortoiliac revascularizations, and prosthetic conduit use.

Graft Failure After Revascularization for Chronic Limb-Threatening Ischaemia (CLTI) Patients: The Role of Graft Surveillance.

Introduction Failure of infrainguinal bypass grafts remains a major problem tackled by vascular surgeons despite a meticulous surgical technique. All infrainguinal bypasses should go under routine surveillance to pick the grafts at risk for the prevention of graft failure. Objectives The aim was to find out if we were adhering to the European Society of Vascular Surgery (ESVS) guidelines in the management of chronic limb-threatening ischaemia (CLTI) patients, including postoperative follow-up and to monitor whether the patients were having postoperative duplex surveillance scans to pick any graft at risk. Methods All patients who underwent infra-inguinal bypass procedures for CLTI during the last eight months (from mid-January to mid-September 2023) in our vascular unit were included. Retrospective data were collected. Results A total of 38 patients had lower limb bypass procedures over the last eight months (from 15 January till 14 September 2023). However, two femoral-femoral (fem-fem) crossovers, one Ilio-popliteal, and one pedal bypass were excluded. Thus, a total of 36 patients were included in the study (n=34). The vast majority (n=27, 79.4%) had femoro popliteal bypass anastomosing distally to above knee (AK) or below knee (BK) popliteal artery, and the rest (n=7, 20.5%) had distal bypass (fem-distal or pop-distal bypass). Moreover, 18% of patients had amputation, 15% of patients died, and 61% of the remaining patients were on surveillance. Of those, who were not on surveillance, 44% of them had graft occlusion. Conclusion Surveillance can predict graft at risk, and the graft occlusion can be prevented by appropriate intervention. Every vascular unit should have its own post-procedural follow-up strategies.

Increased anti-thrombotic therapy is associated with decreased major adverse limb events in patients with low wound and foot infection scores.

The optimal anti-thrombotic management of patients after lower extremity bypass has yet to be fully elucidated, in part due to significant heterogeneity in patient presentation and practice patterns. The Wound, Ischemia, and foot Infection (WIfI) score is a validated scoring system to assist in the management of patients with chronic limb threatening ischemia (CLTI). We hypothesized that performing a restriction analysis based on WIFI scores would assist in the postoperative anti-thrombotic management of patients undergoing infrainguinal bypass. A retrospective cohort of infrainguinal bypass procedures completed at a single hospital system between January 2018 and January 2021 was selected, and preoperative WIfI scores were extracted for each patient. Patients with either Wound scores of 2 and 3, or Ischemia Scores of 0 and 1, or Foot Infection Scores of 3 were excluded. Based on the type of anti-thrombotic regimen on discharge, demographics, comorbidities, type of bypass, 30-day rates of graft occlusion, major amputation, mortality, and major adverse limb events (MALE) were analyzed. Statistical analysis included t-tests, chi square tests, and time-to-event survival analysis. 230 procedures were included in the study. 69 (30.0%) patients were discharged on single antiplatelet therapy (SAPT), compared to 161 (70.0%) who were discharged on either dual antiplatelet therapy or anticoagulation (DAPT/AC). There was a higher prevalence of bypasses using prosthetic conduit in the DAPT/AC group (45.9 vs 31.8%, p = .047); no other demographic or procedural variable analyzed had any significant differences. At 30-days postoperatively, there was no significant difference in postoperative reintervention rates, however, the DAPT/AC group had significantly lower rates of mortality (1.2 vs 7.2%, p = .01), major amputation (1.2% vs 5.8%, p = .04), and MALE (3.7 vs 13.0%, p < .01). There were no significant differences in bleeding complications. Survival analysis demonstrated that MALE-free survival was higher in the DAPT/AC group compared to the SAPT group (p < .01). On Cox regression analysis, DAPT/AC was associated with significantly decreased rates of MALE + mortality (Hazard Ratio (HR) 0.20 [0.06 - 0.66]). Lower extremity bypasses patients with low Wound and low foot Infection scores who are discharged on DAPT/AC postoperatively have a significantly higher 30-day MALE-free survival rate compared to patients discharged on SAPT; consideration could be made to preferentially discharge such post-bypass patients on DAPT/AC.

Impact of cilostazol on prevention of late failure of autologous vein grafts.

The effectiveness of postoperative medication for the prevention of late graft failure is controversial. We conducted the present study to investigate whether cilostazol improved the mid-term outcomes after infrainguinal autologous vein bypass for chronic limb-threatening ischemia (CLTI). From April 1994 to March 2022, we performed 590 de novo infrainguinal bypass procedures using autologous vein grafts (AVGs) in three hospitals. The bypass grafts were classified according to the postoperative prescription of cilostazol. The loss of graft patency and major adverse limb events (MALEs) were set as endpoints. Patients who died within 30days and grafts that lost primary patency within 30days after surgery were excluded. Data up to 3years were analyzed. The cumulative primary patency (PP), assisted primary patency (AP), secondary patency (SP), and freedom from MALE (ffMALE) rates were calculated by the Kaplan-Meier method and compared between the cilostazol group and the non-cilostazol group. After a propensity score matching, same statistical analyses were performed. In addition, a Cox proportional hazards regression analysis that included preoperative factors, intraoperative factors, and postoperative medications was performed to identify whether cilostazol is an independent predictor for the outcomes. A total of 523 AVGs met inclusion criteria. Kaplan-Meier curves showed that the cilostazol group was superior to the non-cilostazol group in all outcomes, while the cilostazol group was superior to the non-cilostazol group in AP and SP after a propensity score matching. A multivariable analysis showed that non-use of cilostazol was identified as an independent predictor for loss of AP, SP, and ffMALE. Cilostazol improved the mid-term outcomes after infrainguinal autologous vein bypass.

Sex-based differences in outcomes after lower extremity bypass for chronic limb-threatening ischemia

Background and aimsLower extremity bypass surgery is an effective treatment option for patients with chronic limb-threatening ischemia (CLTI). Recent studies have suggested that sex-based differences may impact patient outcomes following lower extremity revascularization, however, results have been inconsistent. MethodsIn this multicenter analysis, we retrospectively identified all infrainguinal bypass procedures performed for CLTI from 2002 to 2021. Patients were separated into two groups based on sex. Primary outcomes were major limb amputation and reintervention for graft patency. ResultsOf 843 bypasses performed over the study period, 347 (41.2%) patients were female. Racial/ethnic distribution and medical comorbidities were similar across sex groups. Surgical indications and operative details were also similar between groups, including conduit type (49.9% autogenous), bypass target (65.4% infrageniculate), and concurrent endarterectomy (38.9%). Female and male patients had similar hospital length of stay (6 days [4-9] vs 6 days [4-9]), hospital readmission (25.6% vs 25.0%), and postoperative complications (p=NS each). Female patients had higher major amputation rates (10.1% vs 6.3%, p=0.04) after one year, whereas reintervention rates were similar between groups (26.2% vs 24.6%, p=NS). After accounting for patient factors, female sex (odds ratio [OR] 1.02 [1.00–1.04]), infrageniculate target (OR 1.02 [1.00–1.04]), and bypass for tissue loss (OR 1.02 [1.00–1.04]) were associated with major amputation after bypass (p<0.05 each). ConclusionsFemale sex is associated with a small but significant increase major amputation after lower extremity bypass surgery for CLTI, despite similar clinical presentation, medical comorbidities, and operative details. These data support the increasingly recognized sex disparities in peripheral arterial disease.

Factors Associated With Limb Failure to Rescue After Infrainguinal Bypass Surgery

Bypass graft failure and major amputation are among the most dreaded complications of infrainguinal bypass surgery. In this large multicenter analysis, we examined the incidence and risk factors for limb failure to rescue (FTR) after either bypass surgery or bypass graft failure. A prospectively maintained, multicenter database was retrospectively queried for all infrainguinal bypass procedures performed between 2002 and 2021. Redo bypasses were excluded. The primary outcome was limb FTR, defined as major ipsilateral limb amputation within 90 days after index bypass surgery or bypass graft failure. Bypass graft failure was defined as requiring reintervention for critical stenosis or occlusion of the bypass graft. Graft rescue was defined as bypass graft failure without subsequent major ipsilateral limb amputation within 90 days. Multivariable logistic regression analysis was used to identify risk factors for bypass graft failure and for limb FTR. Over the study period, 1315 infrainguinal bypass procedures were performed across five hospitals. There were 25 major amputations within 90 days of initial bypass. Bypass graft failure was diagnosed in an additional 503 (38.3%) patients. The median time to graft failure was 239 days (interquartile range: 90-667 days). On multivariable analysis, bypass for tissue loss (odds ratio [OR]: 1.38, 95% confidence interval [CI]: 1.03-1.83; P = .03) was the only risk factor identified for graft failure. Of patients with graft failure, 33 had major amputation, leading to an overall limb FTR incidence of 4.4% (n = 58) over a median follow-up period of 1.7 years (Fig). Patient demographics, medical comorbidities, and bypass conduits were similar between the FTR and graft rescue groups (n = NS each). The FTR group more frequently underwent bypass for tissue loss (51.7% vs 29.8%, P = .002), and an infrageniculate bypass target was more frequently used in FTR compared with graft rescue patients (81.0% vs 60.4%, P = .002). Anticoagulation (34.5% in FTR vs 37.7% in rescue) and dual antiplatelet therapy (15.5% vs 22.1%, respectively) were similar between the groups (P = NS each). Risk factors for FTR included infrageniculate target (OR: 2.42, 95% CI: 1.22-4.08; P = .01), Black race (OR: 2.47, 95% CI: 1.04-5.84; P = .04), and bypass for tissue loss (OR: 4.75, 95% CI: 1.41-16.0; P = .01). Anticoagulation and dual antiplatelet therapy were not associated with loss of graft patency or FTR. Limb FTR after infrainguinal bypass surgery is associated with nonmodifiable risk factors and may represent the progression of underlying disease. These data may help inform vascular surgeons in counseling patients with failing bypass grafts. Further investigation of care delivery factors improving the likelihood of graft salvage may be warranted.

Routine Completion Angiography for Infrainguinal Bypasses Using Prosthetic Conduit: No Effect on Postoperative Patency

Recent studies have demonstrated increased postoperative patency with the use of routine completion angiography for bypass using venous conduit. Compared to vein conduits, however, prosthetic conduits are less plagued by technical issues such as unlysed valves or arteriovenous fistulae. The effect of routine completion angiography on bypass patency in prosthetic bypasses has yet to be compared to the more traditional selective use of completion imaging. A retrospective review of all infrainguinal bypass procedures using prosthetic conduit completed at a single hospital system from 2001 to 2018 was performed. Demographics, comorbidities, intraoperative reintervention rates, and 30-day rates of graft thrombosis were analyzed. Statistical analysis included t-tests, chi-square tests, and cox regression. Four hundred and ninety-eight bypasses that were performed in 426 patients met inclusion criteria. Fifty-six (11.2%) bypasses were classified into the routine completion angiogram group compared to 442 (88.8%) into the no completion angiogram group. Patients who underwent routine completion angiograms had a rate of intraoperative reintervention of 21.4%. When comparing bypasses that underwent routine completion angiography versus no completion angiography, there were no significant differences in rates of reintervention (3.5% vs. 4.5%, P=0.74) or graft occlusion (3.5% vs. 4.7%, P=0.69) at 30-days postoperatively. Almost one-quarter of lower extremity bypasses using prosthetic conduit that undergo routine completion angiography undergo postangiogram bypass revision; however, this is not associated with an increased graft patency at 30 days postoperatively.

Preoperative Anemia is Associated with Poorer Postoperative Outcomes in Patients Undergoing Infrainguinal Bypass Surgery

Preoperative anemia is an important, modifiable risk factor among surgical patients. However, data are scarce on the impact of preoperative anemia on postoperative outcomes after infrainguinal bypass. In this multi-institutional analysis, data were retrospectively collected on all infrainguinal bypass procedures performed between 2010 and 2020. Patients were grouped by preoperative hemoglobin as per the National Cancer Institute anemia scale (mild, 10g/dL-lower limit of normal; moderate, 8.0-9.9g/dL; severe, 6.5-7.9g/dL). Multivariable comparisons were performed using logistic regression analysis. A total of 492 patients underwent bypass for peripheral artery disease over the 10-year study period. Median preoperative hemoglobin was 11.0g/dL (interquartile range 9.5-12.7) and median follow-up was 1.7years. Preoperative anemia was prevalent among bypass patients (mild 52.4% [n=258], moderate 26.4% [n=130], and severe 5.1% [n=25]). Women were more likely to have moderate (49.2% [women] vs. 50.8% [men]) or severe anemia (52.0% [women] vs. 48.0% [men]) compared with normal hemoglobin (17.7% [women] vs. 82.3% [men]) (P<0.001). Patients with preoperative anemia were more likely to present with tissue loss (22.8% [normal] vs. 47.7% [moderate] vs. 52.0% [severe], P=0.01). Bypass target and conduit types were similar between groups. Anemic patients had longer median hospital length of stay compared with nonanemic patients (4days [normal] vs. 5days [mild] vs. 6days [moderate] vs. 7days [severe], P<0.001). Postoperative mortality at 30 days was similar across anemia groups (2.5% [normal] vs. 4.6% [moderate] vs. 8.0% [severe], P=0.23). On multivariable analysis, however, postoperative mortality was independently associated with severe anemia (odds ratio 7.5 [1.2-48.8], P=0.04) and male gender (odds ratio 7.5 [1.2-26.4], P=0.03). Preoperative anemia is common among patients undergoing infrainguinal bypass surgery and is an independent risk factor for postoperative mortality. Future investigation is needed to determine whether correction of anemia improves postoperative outcomes in these high-risk patients.

Impact of tibial bypass conduit on long-term amputation-free survival and primary patency in the Vascular Quality Initiative

ObjectiveMuch research remains focused on tibial bypass conduit selection. We sought to describe long-term amputation-free survival (AFS) and primary patency (PP) of patients undergoing tibial bypass by conduit type and configuration across several permutations in the Society for Vascular Surgery Vascular Quality Initiative. MethodsPatients in the Vascular Quality Initiative registry undergoing elective first-time femoral- or popliteal-to-tibial bypass for occlusive disease involving rest pain or tissue loss were identified. Prior ipsilateral infrainguinal bypass or concomitant procedures were excluded. Outcomes of interest included patient AFS at 22 months and PP at 1 year (defined as freedom from revision, thrombectomy, or graft occlusion). ResultsA total of 4192 bypasses were identified. The majority utilized great saphenous vein (GSV) (76.2%), followed by polytetrafluoroethylene (10.6%), nonautologous biologic (6.5%), composite (3.3%), arm vein (2.8%), and small saphenous vein (0.6%). Compared with all prosthetic and composite bypasses, vein grafts had the best AFS (76.4%; P < .0001) and PP (68.1%; P = .041). Of the single segment vein conduits, GSV bypasses had the best PP (69.1%) and arm vein the worst (60.2%). AFS and PP were similar between single-segment GSV orientations. Single-segment GSV bypasses exhibited better PP than multiple segment bypasses (69.1% vs 54.6%; P = .0016). PP was significantly better for polytetrafluoroethylene compared with nonautologous biologic (68.4% vs 51.2%; P = .0039). PP did not significantly differ between vein cuff for prosthetic bypass compared with no vein cuff (69.1% vs 59.7%; P = .091). PP was not significantly different between single-segment GSV and prosthetic grafts with vein cuff (69.1% vs 69.1%; P = .51). There were no significant differences in AFS comparing arm vein, prosthetic bypass with vein cuff, or composite grafts (67.2% vs 63.8% vs 59.3%; P = .092), as well as in PP (60.2% vs 69.1% vs 54.8%; P = .14). ConclusionsSingle-segment vein bypass was only marginally the most optimal conduit. Surprisingly, there may be more equipoise among conduit types, particularly in the absence of adequate GSV. Prosthetic grafts overall may not be as disadvantaged in the long term as initially thought, especially when compared with arm vein, as prosthetic bypass with vein cuff did not significantly differ in PP. Similarly, a composite conduit may not impact long-term outcomes. These data suggest that conduit choice may not impact outcomes to the degree previously thought and that other factors may have a greater impact than presumed, especially in conduit limited situations.

Modern Lower Extremity Bypass Outcomes by Anesthesia Type in the Veteran Population

Lower extremity bypass (LEB) revascularization can be performed under general (GA) or neuraxial anesthesia (NA). Studies show that the use of NA may decrease morbidity, 30-day mortality, and hospital length-of-stay (LOS). The goal of our analysis is to examine the differences in postsurgical outcomes following LEB between patients who undergo GA compared to NA in the Veteran Affairs Surgical Quality Improvement Program (VASQIP) database. After IRB approval, the VASQIP database was assessed for patients who underwent LEB between 1998-2018. Only infrainguinal bypass procedures and anesthesia type classified as "general," "epidural," or "spinal" were included. The neuraxial cohort includes both spinal and epidural anesthesia patients. The Risk Analysis Index (RAI), a validated measure of frailty, was additionally calculated for each patient. Chi squared, paired t-test, and binary logistic regression were used to compare the cohorts. During this period, 22,960 veterans underwent LEB recorded in VASQIP. Compared to those who underwent surgery under GA, patients with procedures performed using NA were older (66.4 ± 9.6 years vs. 65.3 ± 9 years respectively; P <0.001) and more frail (average RAI score 25.7 ± 7.0 vs. 24.9 ± 6.7; P < 0.001). Operative time was shorter in the NA group (4.1 ± 1.7 hrs vs. 4.7 ± 3.0 hrs; P < 0.001) and fewer cases were emergent (1.55% vs. 4.13%; P <0.001). Patients in the GA group had higher rates of postoperative prolonged ileus (0.31% vs. 0.00%; P=0.03), pneumonia (1.60% vs. 1.06%; P=0.025), deep wound infection (2.67% vs. 2.61%; P=0.01), sepsis (1.68% vs. 0.79%; P < 0.001), reintubation (1.80% vs. 1.30%) (P=0.04),and number of packed red blood cell (pRBC) transfused intraoperatively (0.39 ± 1.21 units vs. 0.22 ± 0.79 units; P <0.001). There was no significant difference in rate of graft failure, return to the OR, myocardial infarction, death, or LOS. In regression analysis, those undergoing NA were less likely to require pRBC transfusion intraoperatively (OR: 0.43; 95% CI: 0.31-0.61; P < 0.001), however no other outcomes reached statistical significance. Although younger and less frail, veteran patients undergoing GA for lower extremity revascularization had higher rates of postoperative ileus, pneumonia, deep wound infection, sepsis, and need for transfusion as compared to those undergoing NA. There was no significant difference in the rate of other major complications, myocardial infarction, death or LOS. After adjustment, only intraoperative transfusion remained statistically significant, likely reflecting longer and more complex cases for those that undergo general anesthesia rather than the effect of anesthetic choice itself.

Infrainguinal bypass under triple nerve block in patients with severely compromised left ventricular ejection fraction and chronic limb-threatening ischemia

A severely compromised left ventricular ejection fraction (LVEF) is a major limitation for lower extremity bypass reconstruction both under general anesthesia or neuraxial anesthesia (NA). A series of eight infrainguinal bypass procedures were performed under peripheral nerve block in five patients (three males and two females; median age, 67 years) with chronic limb-threatening ischemia and a preoperative LVEF of 35% or less (median, 27%; range, 20%-35%). There were no conversions to neuraxial anesthesia/general anesthesia or early postoperative complications. This study showed that open infrainguinal reconstructions can be performed safely under peripheral nerve blockade in this vulnerable category of patients.

Remote results of infrainguinal bypass graft procedures for critical lower limb ischaemia

The study was aimed at assessing the remote results of infrainguinal reconstructions in patients with critical lower limb ischaemia depending upon the bypass graft material used. Analysed herein are the results of 237 infrainguinal bypass procedures performed over a 9-year period from January 1st, 2010 to December 31st, 2018. The patients were divided into three groups depending on the level of the distal anastomosis. Each group was then subdivided into subgroups based on the bypass graft material. Group One comprised 40 patients having endured femoral-proximal-popliteal bypass grafting. Group Two was composed of 77 patients after femoral-distal-popliteal bypass graft operations. Group Three included 120 patients after femorotibial bypass graft procedures. The comparative analysis was carried out in the first group between autovenous and synthetic grafts, in the second group - between autovenous, synthetic grafts and xenografts, and in the third group - between autovenous, composite grafts and xenografts. The primary patency rates at 1, 3, and 5 years in the first group amounted to 92, 88, and 73%, in the second group to 68, 60, 45% and in the third group - to 58, 49, and 43%, respectively. The 1-, 3-, and 5-year limb salvage rates in the first group were 100, 100, and 87%, in the second group - 90, 85, 73%; and in the third group - 90, 80, and 79%, respectively. Statistically significant differences were observed only when comparing the femoral-proximal and tibial grafts (p=0.039). Patients' survival at 1, 3, and 5 years in all groups turned out to be approximately similar, amounting in the first group to 92, 84, and 61%, in the second group to 96, 91, 71%, and in the third group to 88, 77, and 69%, respectively (p=0.87). In the first group, there were no significant differences between autovenous and synthetic grafts for any of the parameters studied. In the second group, the synthetic grafts (20%) were significantly inferior by the 5-year patency to autovenous grafts (65%) and xenografts (56%), as well as by the limb salvage rate to autovenous grafts (47 versus 84%). In the third group, the 5-year patency was the worst for the subgroup of composite grafts (15%), with the patency of xenografts being slightly inferior to that of autovenous grafts (33 vs. 55%). In patients presenting with critical ischaemia and requiring infrainguinal bypass grafting, as an alternative to an autovein if unavailable may serve synthetic prostheses when shunting to the proximal portion of the popliteal artery, or xenografts when shunting to the distal portion of the popliteal artery or tibial arteries. Despite worse patency, with their help it is possible to achieve regression of critical ischaemia and an acceptable limb salvage rate, which is comparable to the results of autovenous grafts.

Patient and Institutional Costs of Failure of Angioplasty of the Superficial Femoral Artery

Debate surrounds the optimal management of superficial femoral artery (SFA) disease. Randomized trial data rarely reflect real world findings, specifically the consequences to the patient of angioplasty failure. We observed the effect of a failed SFA angioplasty on the need for repeated clinic visits, hospital readmissions, imaging requirements, and reinterventions. We reviewed a consecutive series of 148 patients (94 men, median age 72years) undergoing solely SFA angioplasty over a 2-year period. Patient preangioplasty demographics and 2-year post-PTA follow-up data were collated, including hospital attendances (inpatient/outpatient), further imaging (including radiation exposure) and revascularization attempts. We defined "failed angioplasty" as presence of clinical symptoms with radiological evidence of significant restenosis after an initial successful primary SFA angioplasty. Fifty-four patients represented with a failed angioplasty (median time of 4months after index PTA). In this group, failure of index angioplasty resulted in a further 185 restenosis-related clinic visits and a total of 537 bed days of inpatient stay. This group underwent a further 149 imaging events and required a further 34 endovascular revascularization procedures and 12 infrainguinal bypass procedures. These interventions and investigations corresponded to overall effective radiation dose across all patients of 190.69mSv. Of the cohort of 99 patients who did not have a "failed angioplasty," they required 100 clinic visits, 21 further scans (total radiation dose 6.42mSv), and 36 bed days of inpatient admission. Failed angioplasty results in significant additional consequences for patients and health-care systems. Further work should focus on refining decision-making, providing the right procedure to the right patient at the right time.

Frailty Increases Reinterventions for Surgical Site Infections After Infrainguinal Bypass Procedures

Surgical site infection (SSI) contributes to a high burden of vascular morbidity, particularly in lower limb revascularizations. While frailty has been associated with higher mortality and readmission rates after surgery, less is known about frailty’s relationship with SSI. Thus, we sought to explore the association of frailty with SSI after infrainguinal bypass.

Contemporary Outcomes Following Infra-inguinal Bypass. A Recent Vascular Hub Exeprience

Introduction: Infra-inguinal bypass is the most common surgical procedure performed for critical lower extremity ischaemia. Outcomes in-terms of; survival, graft patency and freedom from major amputation vary significantly in the literature and are influenced by many factors including patient co-morbidity, anatomical site of bypass and choice of bypass conduit. Here is presented contemporary outcomes of all infra-inguinal bypass grafts performed at a single vascular hub between January 2015 and January 2019. Methods: This is a single centre, retrospective cohort study. Demographic, disease and procedural data was extracted from eligible cases identified within a national vascular registry (VSQIP-NVR). This was then cross-referenced with hospital episode statistic (HES) codes to ensure adequate data capture. In-house electronic records (clinical results reporting system, CRRS) were interrogated for follow up, re-intervention and survival outcome measures. Statistical analysis was performed using SPSS 25 (IBM). Survival estimates were calculated using the Kaplan-Meier method. Results: 185 Eligible infra inguinal bypass procedures were Identified. This consisted of 79 elective and 106 non-elective admissions. Mean age at surgery was 69 (±13) years. Tissue loss was present in 46%(n=85) of patients. Autologous vein was the conduit of choice in 90% (n=165) with reversed vein and in-situ vein accounting for 76% (n=143) and 14% (n=26) respectively. 87% of patients were enrolled into ultrasound surveillance. Mean duration of follow up was 42 (0-51) months. At 6 months, 1 and 3 years primary patency was 68%, 60% and 54% respectively.Mean time to first intervention was 14 months (IQR 3-22 months). 88% of all interventions to maintain patency were carried out by 24 months.At 6 months, 1 and 3 years secondary patency was 93%, 88% & 86% respectively. At 6 months, 1 and 3 years limb salvagewas 85%, 81% & 79% respectively. Estimated survival and limb salvage rates were significantly lower in non-elective procedures in comparison to elective procedures (p=0.07 & p=0.03 respectively). There was no difference in primary or secondary patency between popliteal and distal bypasses, however, limb salvage was significantly better in popliteal bypasses (p=0.03). Conclusion: Infra-inguinal bypass remains the gold standard in lower limb revascularisation. This case series highlights excellent patency and limb salvage into the medium term. We would advocate ultrasound surveillance as a significant proportion (38%) of grafts require maintenance to ensure continued patency, our data would support a surveillance period of 24-months as sufficient, 88% of all graft interventions to maintain patency were performed by 24 months. It may be possible limit graft surveillance, provided patients have been intervention free. As anticipated, patients who undergo non elective bypass are at greater risk of major amputation than their elective counterparts. Disclosure: Nothing to disclose

Outcomes of Infrainguinal Bypass Procedures in Diabetic Patients with Ischaemic Foot Ulcers: A Sri Lankan Experience in Limb Salvage

Outcomes of Infrainguinal Bypass Procedures in Diabetic Patients with Ischaemic Foot Ulcers: A Sri Lankan Experience in Limb Salvage

Impact of Medicaid Expansion of the Affordable Care on the Outcomes of Lower Extremity Bypass for Patients With Peripheral Artery Disease in the Vascular Quality Initiative Database.

The aim of this study was to evaluate changes in the utilization and outcomes of surgery after Medicaid Expansion (ME) for patients with peripheral artery disease (PAD). Recent studies have demonstrated increased insurance coverage and improved care with the Affordable Care Act's (ACA) state expansion of Medicaid. Infrainguinal bypass procedures performed due to occlusive pathology in the Vascular Quality Initiative database between 2010 and 2017 were included. Primary outcomes including postoperative mortality and major adverse limb events (MALE) at 1-year of follow-up were analyzed using interrupted time-series analysis (ITS). Out of 26,446 infrainguinal bypass procedures, 13,955 (52.8%) were included in this analysis. ME states witnessed an annual decrease in infrainguinal surgery for acute ischemia [annual change in post vs pre-ME period (95% confidence interval): -4.3% (-7.5% to -1.0%), P = 0.02] and an increase in revascularization for claudication [3.7% (1.7%-5.6%), P = 0.01]. Among nonacute cases, elective procedures increased in ME states [3.9% (0.1%-7.7%), P = 0.05] along with a significant annual decrease in in-hospital mortality [-0.4% (-0.8 to -0.02), P = 0.04) and MALE at 1 year of follow up [-9.0% (-20.3 to 2.3), P = 0.09]. These results were statistically significant after comparing them with the annual trend changes in states which did not adopt ME. The adoption of ME in 2014 was associated with significant increase in the use of infrainguinal bypass for nonsevere and elective cases, along with improved in-hospital mortality and MALE at 1 year. Longer follow-up is needed to evaluate the impact of ME on other aspects of care and longer term outcomes of PAD patients.

Analysis of Thirty-Day Readmission after Infrainguinal Bypass

The Vascular Study Group of New England (VSGNE) conducted a pilot study evaluating the feasibility of 30-day data collection in patients undergoing infrainguinal bypass (INFRA) which was subsequently expanded to include a limited number of additional sites within the Vascular Quality Initiative (VQI). The purpose of our study was to use these data to evaluate the incidence of 30-day readmission after infrainguinal bypass. A secondary goal of the study was to perform a critical appraisal of the data elements and definitions in the 30-day dataset. All infrainguinal bypass procedures performed during the pilot study period (7/2008 and 4/2016) were identified and merged with a dataset containing the 30-day data. Incidence and types of readmission were assessed. The primary endpoint was 30-day readmission, defined as any hospital readmission within 30days of index operation; unplanned 30-day readmission was the secondary endpoint. Covariates tested for association with the primary and secondary endpoints included patient demographics, comorbidities, procedural, and postoperative characteristics. Variables significant on univariate screen (P<0.2) were evaluated with logistic regression to identify independent determinants. Of 9,847 infrainguinal bypass patients, 5,842 (59%) patients were identified with 30-day data, and 907 (16%) were readmitted within 30 days. Of readmissions, 675 (85%) were unplanned. Potentially modifiable independent determinants of any 30-day readmission included 30-day surgical site infection (SSI) (odds ratio [OR]: 10, 95% confidence interval [CI]: 8.2-12, P<0.0001), postoperative acute kidney injury (OR: 1.7, 95% CI: 1.2-2.5, P=0.002), and discharge anticoagulation (OR: 1.2, 95% CI: 1.04-1.5; P=0.02). Predictors of unplanned 30-day readmission were very similar but identified in-hospital major amputation as an additional independent predictor (OR: 2.8, 95% CI: 1.6-4.9, P=0.0002). This study demonstrates the interest in, and value of, 30-day data collection in VSGNE/VQI and documents the frequency of readmission after infrainguinal bypass. Readmission within 30 days is strongly associated with SSI, stressing the importance of efforts to decrease this complication. Given that many other predictors are unmodifiable, 30-day readmission is only appropriate as a quality metric if it is risk adjusted using large, real-world datasets such as VQI. Lessons learned from this analysis can be used to select optimal 30-day data elements.

The impact of foot infection on infrainguinal bypass outcomes in patients with chronic limb-threatening ischemia

BackgroundDespite advances in endovascular therapy, infrainguinal bypass continues to play a major role in achieving limb salvage. In this study, we sought to compare outcomes of infrainguinal bypass in patients with limb-threatening ischemia who presented with or without foot infection. MethodsWe conducted a retrospective cohort study of patients who underwent infrainguinal bypass for chronic limb-threatening ischemia at a single institution. End points of interest included long-term mortality, 45-day readmission, postoperative length of stay (LOS), major amputation, and time to wound healing. Multivariable Cox, logistic, and robust regressions were used to model time to event outcomes, readmission rates, and LOS. ResultsThere were 454 infrainguinal bypass procedures analyzed. Demographics and baseline characteristics were similar, except congestive heart failure and diabetes were more common in the infection group. Presence of foot infection had no impact on mortality (hazard ratio [HR], 0.78; P = .243). Significant predictors of long-term mortality included increasing age, hypoalbuminemia, and congestive heart failure; preoperative use of clopidogrel was protective. Presence of foot infection was an independent predictor of major amputation. In the multiple regression model, the presence of foot infection was independently associated with amputation rate (HR, 2.14; 95% confidence interval, 1.42-3.22; P < .001); use of venous conduit and increasing age and body mass index were protective. Foot infection was an independent predictor of prolonged LOS (mean LOS was 1.54 days longer in patients with vs those without infection; P = .001). Other independent predictors of prolonged LOS included intraoperative blood loss and reoperation; history of continuous preoperative aspirin use and normal baseline renal function and albumin levels were associated with decreased LOS. Readmission was influenced by reoperation (odds ratio [OR], 2.51; P < .001) but not by presence of foot infection (OR, 1.21; P = .349). There was a strong trend for prolonged wound healing time in patients with diabetes (HR, 1.58; P = .05) but not in those with foot infection (OR, 0.74; P = .36). ConclusionsAmong patients requiring infrainguinal bypass for limb-threatening ischemia, infection was more common in patients with diabetes and was a significant predictor of major amputation and prolonged LOS. Infection was not predictive of mortality, wound healing time, or readmission. These findings lend support to the inclusion of infection in risk stratification schemes for patients with chronic limb-threatening ischemia, as recommended in the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system, because of its adverse impacts on limb salvage.

The impact of current smoking on outcomes after infrainguinal bypass for claudication

ObjectiveAlthough smoking cessation is a benchmark of medical management of intermittent claudication, many patients require further revascularization. Currently, revascularization among smokers is a controversial topic, and practice patterns differ institutionally, regionally, and nationally. Patients who smoke at the time of revascularization are thought to have a poor prognosis, but data on this topic are limited. The purpose of this study was to evaluate the impact of smoking on outcomes after infrainguinal bypass for claudication. MethodsData from the national Vascular Quality Initiative from 2004 to 2014 were used to identify infrainguinal bypasses performed for claudication. Patients were categorized as former smokers (quit >1 year before intervention) and current smokers (smoking within 1 year of intervention). Demographic and comorbid differences of categorical variables were assessed. Significant predictors were included in adjusted Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) by smoking status for outcomes of major adverse limb event (MALE), amputation-free survival, limb loss, death, and MALE or death. Cumulative incidence curves were created using competing risks modeling. ResultsWe identified 2913 patients (25% female, 9% black) undergoing incident infrainguinal bypass grafting for claudication. There were 1437 current smokers and 1476 former smokers in our study. Current smoking status was a significant predictor of MALE (HR, 1.27; 95% CI, 1.00-1.60; P = .048) and MALE or death (HR, 1.22; 95% CI, 1.03-1.44; P = .02). Other factors found to be independently associated with poor outcomes in adjusted models included black race, below-knee bypass grafting, use of prosthetic conduit, and dialysis dependence. ConclusionsCurrent smokers undergoing an infrainguinal bypass procedure for claudication experienced more MALEs than former smokers did. Future studies with longer term follow-up should address limitations of this study by identifying a data source with long-term follow-up examining the relationship of smoking exposure (pack history and duration) with outcomes.