Infrainguinal Bypass In Patients Research Articles

Prior Endovascular Intervention Is Not Associated With Unfavorable Outcomes in Infrainguinal Bypass Surgery for Chronic Limb-Threatening Ischemia: A Propensity Score-Matched Analysis of the VQI-Medicare-Linked Database

Bypass with an autogenous vein is still considered the gold standard for patients with chronic limb-threatening ischemia (CLTI). However, in the endovascular era, the majority of patients undergo a peripheral vascular intervention (PVI) as the first-line treatment. The aim of this study was to evaluate the impact of prior endovascular interventions on perioperative and long-term outcomes of infrainguinal bypass in patients with CLTI.

Predictors of Major Adverse Limb Events After Infrainguinal Bypass in Patients with Diabetes

ObjectiveDiabetes mellitus is a major risk factor for peripheral artery disease (PAD). The association of diabetes with major adverse limb events (MALE) after lower extremity revascularization (LER) remains controversial as patients with diabetes are often analyzed as a homogenous group. This study examines the impact of insulin use and glucose control on the outcomes of infrainguinal bypass. Our hypothesis is that insulin therapy and hemoglobin A1c (A1c) are predictors of MALE and might be used to stratify outcomes in of LER in patients with diabetes. MethodsThe Vascular Quality Initiative (VQI) database for infrainguinal bypass (2007-2021) was reviewed. Patients with diabetes undergoing bypass for PAD were included. Patients on dialysis or with kidney transplant were excluded. The characteristics and outcomes of patients with insulin requiring diabetes mellitus (IRDM) were compared with patients not requiring insulin (NIRDM). ResultsA total of 9,686 patients with diabetes (56% IRDM) underwent bypass. Patients with IRDM were significantly younger than patients with NIRDM and more likely to be female, African American, and Hispanic. After a mean follow-up of 427 days post-operation, patients with IRDM had significantly lower primary patency and higher major amputation, MALE, and mortality. (Table) Regression analyses demonstrated that insulin use, but not A1c, was independently associated with higher risk of MALE (HR = 1.17 [1.06-1.29]) and mortality (HR=1.28 [1.16-1.43]). ConclusionPrevalent insulin use, but not the degree of A1c control, is a significant predictor of MALE and survival after infrainguinal bypass and should be used to stratify the outcomes of LER in patients with diabetes.

Alternative autologous and biologic conduits have worse outcomes than prosthetic grafts for infrainguinal bypass in patients with chronic limb-threatening ischemia

Objective: Single segment great saphenous vein (GSV) is the preferred conduit in infrainguinal bypass. Alternative autologous conduits (AAC) and nonautologous biologic conduits (NABC) are thought to be a better alternative to traditional prosthetic conduits (PC) in the absence of GSV. In this study we analyzed the outcomes of these alternative conduits in lower extremity bypasses (LEB) in patients with chronic limb-threatening ischemia.

Alternative autologous and biologic conduits have worse outcomes than prosthetic grafts for infrainguinal bypass in patients with chronic limb-threatening ischemia

ObjectiveSingle segment great saphenous vein (GSV) is the preferred conduit in infrainguinal bypass. Alternative autologous conduits (AAC) and nonautologous biologic conduits (NABC) are thought to be a better alternative to traditional prosthetic conduits (PC) in the absence of GSV. In this study we analyzed the outcomes of these alternative conduits in lower extremity bypasses (LEB) in patients with chronic limb-threatening ischemia. MethodsThe Vascular Quality Initiative LEB database from 2003 to 2020 was queried for this study, to identify LEB in patients with chronic limb-threatening ischemia. Primary outcomes were graft patency, major adverse limb events (MALE), and MALE-free survival at 1 year. Standard statistical methods were used as appropriate. ResultsWe identified 22,671 LEB procedures (12,810 GSV, 6002 PC, 1907 AAC, and 1952 NABC). Compared with the GSV group, the other conduit patients were significantly older, had more comorbidities, had an increased rate of prior lower extremity interventions, had a higher rate of infrageniculate bypass targets, and were less ambulatory at baseline. The PC, AAC, and NABC groups had significantly higher rates of postoperative morbidity compared with the GSV group. The PC group had a higher 30-day mortality compared with the GSV, AAC, and NABC groups (3% PC vs 2% GSV, 2% AAC, 2% NABC; P = .049). Both PC and NABC had higher 1-year mortality compared with GSV and AAC (13% PC and 13% NABC vs 10% GSV, 10% AAC; P = .02). In an adjusted Cox regression model (stratified by infrageniculate target and adjusted for age, comorbidities, and prior vascular interventions) PC was not significantly different from GSV, but AAC (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.19-1.67; P < .001) and NABC (HR, 1.9; 95% CI, 1.61-2.25; P < .001) were associated with an increased risk of loss of primary patency. A similar association with MALE was observed: both AAC (HR, 1.35; 95% CI, 1.15-1.58; P < .001) and NABC (HR, 1.8; 95% CI, 1.53-2.11; P < .001) were associated with an increased risk of MALE compared with GSV; PC was not significantly different from GSV. ConclusionsIn the absence of GSV, alternative conduits (autologous or nonautologous biologic) do not confer a benefit with regard to graft patency or MALE compared with PCs. Increased operating time or costs associated with the use of these conduits is not justified based on this study.

Outcomes of Infrainguinal Bypass in Patients with Cannabis vs Opioid Use Disorder

Marijuana and opioids are commonly used illicit drugs in the United States and their use continues to rise. Cannabis use disorder (CUD) and Opioid use disorder (OUD) are associated with adverse effects on public health and postoperative outcomes. However, their impact on vascular surgery, specifically infrainguinal bypass repair (IIB). is not well described in the literature. Therefore, our study aimed to assess perioperative outcomes in patients with CUD and OUD who underwent IIB. A retrospective analysis of the National Inpatient Sample database for the years 2005 to 2018 was performed. Using the International Classification of Diseases Clinical Modification, Ninth and Tenth revisions, patients who were diagnosed with peripheral artery disease and underwent IIB repair.were identified. Our primary outcome was the comparison of rates of in-hospital complications between the groups, and the secondary outcomes included analysis of total hospital charges and length of stay. A 1:1 propensity score matching (PSM) CUD and OUD patients to their control groups without the disease was conducted using the nearest-neighbor method. The matching was based on select patient demographics and comorbidities included in our analyses. A total of 190,794 patients were identified: 972 patients with CUD and 682 patients with OUD. In the matched cohorts, patients with a diagnosis of CUD had a higher incidence of in-hospital cardiac complications (adjusted Odds Ratio [aOR], 1.76; 95% Confidence Interval [CI], 0.99-3.12) and acute kidney injury (AKI) (aOR, 1.51; CI, 1.09-2.08). Additionally, total hospital charges and mean length of stay were higher in the CUD group (P < 0.001). Those with OUD had a higher incidence of postoperative respiratory complications (aOR, 1.92; CI, 1.23-2.99), sepsis (aOR, 2.39; CI, 1.32-4.34), infection (aOR, 3.55; CI, 1.16-10.84), AKI (aOR, 2.11; CI,1.47-3.04), major amputations (aOR, 1.69; CI, 1.07-2.69), along with higher total charges and mean length of stay (P < 0.001). Both CUD and OUD have increased incidence of postoperative complications following IIB. The OUD group had generally worse outcomes compared to patients with CUD. Both were associated with a substantial increase in total hospital charges and length of hospital stay. A further prospective study is warranted to provide better insight on the effects of substance use disorders on the procedure's short- and long-term outcomes.

Postoperative and Mid-term Outcomes Following Infrainguinal Bypass in Patients with and Without Prior Major Amputation

Postoperative and Mid-term Outcomes Following Infrainguinal Bypass in Patients with and Without Prior Major Amputation

Interplay of Diabetes Mellitus and End-Stage Renal Disease in Open Revascularization for Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) in patients with end-stage renal disease (ESRD) confers a significant survival disadvantage and is associated with a high major amputation rate. Moreover, diabetes mellitus (DM) is an independent risk factor for developing CLTI. However, the interplay between end-stage renal disease (ESRD) and DM on outcomes after peripheral revascularization for CLTI is not well established. Our goal was to assess the effect of DM on outcomes after an infrainguinal bypass for CLTI in patients with ESRD. Using the Vascular Quality Initiative dataset from January 2003 to March 2020, records for all primary infrainguinal bypasses for CLTI in patients with ESRD were included for analysis. One-year and perioperative outcomes of all-cause mortality, reintervention, amputation-free survival (AFS), and major adverse limb event (MALE) were compared for patients with DM versus those without DM. Of a total of 1,058 patients (66% male) with ESRD, 726 (69%) patients had DM, and 332 patients did not have DM. The DM group was younger (median age, 65years vs. 68years; P=0.002), with higher proportions of obesity (body-mass index>30kg/m2; 34% vs. 19%; P<0.001) and current smokers (26% vs. 19%; P=0.013). The DM group presented more frequently with tissue loss (76% vs. 66%; P<0.001). A distal bypass anastomosis to tibial vessels was more frequently performed in the DM group compared to the non-DM group (57% vs. 45%; P<0.001). DM was independently associated with higher perioperative MALE (OR 1.34; 95% CI, 1.06-1.68; P=0.013), without increased risks of loss of primary patency and composite outcomes of amputation or death. On the mean follow-up of 11.4±5.5months, DM patients had a significantly higher rate of one-year MALEs (43% vs. 32%; P=0.001). However, the one-year primary patency and AFS did not differ significantly. After adjusting for confounders, the risk-adjusted hazards for MALE (HR 1.34; 95% CI, 1.06-1.68; P=0.013) were significantly increased in patients with DM. However, DM was not associated with increased risk of AFS (HR 1.16; 95% CI, 0.91-1.47; P=0.238), or loss of primary patency (HR 1.04; 95% CI, 0.79-1.37; P=0.767). DM and ESRD each independently predict early and late major adverse limb events after an infrainguinal bypass in patients presenting with CLTI. However, in the presence of ESRD, DM may increase perioperative adverse events but does not influence primary patency and AFS at one year. The risk profile associated with ESRD appears to supersede that of DM, with no additive effect.

Preoperative Nutritional Assessment of Controlling Nutritional Status (Conut) is Useful to Estimate Amputation-Free Survival after Infrainguinal Bypass in Patients with Critical Limb Ischemia

Introduction - Most patients with critical limb ischemia (CLI) exhibit severe comorbidities accompanied by malnutrition. However, little information is available about the nutrition status and clinical outcome after infrainguinal bypass in CLI patients. Therefore, the aim of this study was to identify prognostic factors of amputation free survival (AFS) including nutritional score.

Utilization of regional versus general anesthesia and its impact on lower extremity bypass outcomes

ObjectivePrevious studies evaluating general anesthesia (GA) vs regional (epidural/spinal) anesthesia (RA) for infrainguinal bypass have produced conflicting results. The purpose of this study was to analyze the factors associated with contemporary use of RA and to determine whether it is associated with improved outcomes after infrainguinal bypass in patients with critical limb ischemia. MethodsUsing the Vascular Quality Initiative infrainguinal database, a retrospective review identified all critical limb ischemia patients who received an infrainguinal bypass from 2011 through 2016. Patients were then separated by GA or RA. Primary outcomes were perioperative mortality, complications, and length of stay. Predictive factors for RA and perioperative outcomes were analyzed using a mixed-effects model to adjust for center differences. ResultsThere were 16,052 patients identified to have a lower extremity bypass during this time frame with 572 (3.5%) receiving RA. There was a wide variation in the use of RA, with 31% of participating centers not using it at all. Age (67.2 vs 70.3 years; P < .001), chronic obstructive pulmonary disease (25.7% vs 30.9%; P < .001), and urgency of the operation (75.7% vs 80.4%; P = .01) were found to be independently associated with receiving a regional anesthetic. Univariate and multivariate analysis demonstrated that length of stay (6.8 days vs 5.7 days; P < .01), postoperative congestive heart failure (2.3% vs 1.1%; P = .040), and change in renal function (5.7% vs 2.9%; P = .005) were all significant outcomes in favor of RA. There was a trend toward lower mortality rates; however, this did not reach statistical significance. Rates of myocardial infarction, pulmonary complications, and stroke were not found to be statistically different. Coarsened exact matching continued to demonstrate a difference in length of stay and rates of new-onset congestive heart failure in favor of RA. ConclusionsRA is an infrequent but effective form of anesthesia for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may benefit from this form of anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from RA or GA.

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.

Sustained Elevation in Monocyte Levels in Diabetic Patients after Infra- Inguinal Revascularization

Context: Diabetes and atherosclerosis are both pro-inflammatory states that may lead to elevations in monocyte levels. It was previously demonstrated that there is a reduction in monocyte levels after infra-inguinal bypass in patients with critical limb ischemia (CLI). We hypothesized that patients with diabetes would not realize the same reduction in monocyte levels post-bypass as patients without diabetes. Objective: To determine whether patients with diabetes would have a sustained sub-clinical inflammation after resolution of CLI with infra-inguinal bypass, as marked by a persistent elevation of monocyte levels. Design: Patients undergoing lower extremity vascular bypass surgery between 2003 and 2013 at the Syracuse VA Medical Center were retrospectively reviewed. Pre- and post-operative leukocyte count with differential were recorded for each patient and stratified according to the presence of diabetes. Results: Patients with CLI and no bypass failure (n=43) were included for analysis of the primary outcome, change in monocyte level. Diabetic (DM+) patients (n=27) and non-diabetic (DM-) patients (n=16) had similar pre-operative leukocyte counts and differential (p>0.05). In DM-, there was a 5.6% decrease in monocyte count post-operatively, whereas there was an elevation in monocytes in DM+ (+20.8%; p<0.05). The overall rate of complications was significantly greater and the time to develop complications significantly less in DM+ (p<0.05). Conclusion: Diabetic patients have a persistent elevation in monocyte levels even after infra-inguinal vascular bypass as compared with non-diabetic patients. This suggests diabetic patients have persistent sub-clinical inflammation even upon resolution of critical limb ischemia.

Aggressive Wound Care by a Multidisciplinary Team Improves Wound Healing after Infrainguinal Bypass in Patients with Critical Limb Ischemia

A long period is generally required for ischemic ulcer to heal after revascularization. The strategy of postoperative wound care can affect wound healing. This study was conducted to investigate the degree to which aggressive wound care (AWC) by a team of multidisciplinary specialists actually shortens the time to wound healing and increases the rate of wound healing in limbs undergoing surgical bypass for ischemic tissue loss in a real clinical setting. A total of consecutive 126 patients undergoing infrainguinal bypass for tissue loss from April 2011 to March 2015 were reviewed. Prior to March 2013, standard wound care (SWC) including typical daily dressing change with disinfection and irrigation, occasional surgical debridement, and negative pressure wound therapy (when necessary) was performed by vascular surgeons. Thereafter, in addition to SWC, AWC including intense daily bedside surgical debridement under a sciatic nerve block by an anesthesiologist and active skin grafting by a dermatologist, if necessary, was performed. Wound healing and major amputation were defined as the end points. The 1-year outcomes of the 2 groups were calculated using the Kaplan-Meier method and compared, and the significant predictors of each outcome were determined by a Cox proportional hazards analysis. The wound healing of the AWC group was superior to that of the SWC group (AWC versus SWC, 1-year wound healing rate: 92% vs. 80%; mean wound healing time: 48days vs. 82 days; P=0.011), and no significant difference between the 2 regimens in the freedom from major amputation was observed. AWC, Rutherford 5, no wound infection, normal serum albumin, direct angiosome, and cilostazol use were significant predictors of wound healing, and female gender and no cilostazol use were significant predictors of major amputation by a multivariate analysis. Aggressive wound care by the team consisting of multidisciplinary specialists remarkably shortened the time to wound healing and increased the rate of wound healing within 1 year.

Outcomes after open infrainguinal bypass in patients with scleroderma

There are limited reports of outcomes after infrainguinal bypass surgery in patients with scleroderma. This study evaluated the long-term outcome after lower extremity bypass in these patients. The study included all patients with systemic sclerosis who underwent infrainguinal bypass surgery for severe peripheral arterial disease at our institution from January 1, 2007, to August 31, 2014. Kaplan-Meier and Cox regression analyses were used to evaluate graft failure and limb salvage. These outcomes were compared with those of nonscleroderma patients who underwent infrainguinal bypass surgery during the same period. Outcomes were defined and evaluated by Society for Vascular Surgery standards. There were 18 autogenous grafts (6% femoral-popliteal, 11% femoral-tibial, 72% popliteal-tibial, 11% tibial-tibial) placed in 18 limbs from 12 patients with systemic sclerosis. Mean± standard deviation age was 71± 9.5years, and most of the patients were women (83%) and white (78%). All patients presented with critical limb ischemia. History of hypertension and coronary artery disease were 94% and 61%, respectively. All grafts used were autogenous, continuous, and harvested from the lower extremity (nonreversed great saphenous in 61% and reversed great saphenous in 39%). Mean follow-up duration was 2.3± 1.6years. Graft failure was significantly higher in scleroderma patients than in nonscleroderma patients who underwent bypass in the same study period (hazard ratio, 7.2; 95% confidence interval, 1.44-41.4; P= .02). The limb salvage rate was 72%. Long-term outcomes after open infrainguinal bypass surgery in scleroderma patients are significantly worse than those in nonscleroderma patients. Careful consideration of their inherently poor outcomes should be made when reaching a decision for revascularization.

Impact of Foot Infection on Infrainguinal Bypass Outcomes in Patients With Limb-Threatening Ischemia

Despite advances in endovascular therapy, infrainguinal bypass (IB) continues to play a major role in achieving limb salvage in the patients with extensive tissue loss and long-segment occlusive disease. In this study, we sought to compare the outcomes of IB in patients with limb-threatening ischemia who presented with or without foot infection. We conducted a retrospective cohort study of patients who underwent IB for limb-threatening ischemia at a single institution. Patient-related end points of interest included long-term mortality, 6-month readmission, and postoperative length of stay (LOS). Limb-related end points included major amputation (transfemoral, transtibial, or through the knee) and time to wound healing. Multivariable Cox, logistic, and robust regression were used to model time-to-event outcomes, readmission rates, and LOS respectively. Overall, 454 IB procedures that occurred over a 7-year period were analyzed. Demographics and baseline patient characteristics were similar between the infection and noninfection group, except congestive heart failure and diabetes were more common in the infection group. Presence of foot infection had no impact on mortality (HR, 0.72; P = .113). Statistically significant predictors of long-term mortality included increasing age, hypoalbuminemia, and congestive heart failure, whereas preoperative use of clopidogrel was protective (Table I). The presence of foot infection was an independent predictor of major ipsilateral amputation (HR, 1.86; P = .002). Other significant predictors of major amputation on multivariable analysis included history of statin administration, decreasing age, and low body mass index (Table I). In addition, foot infection was an independent predictor of prolonged LOS (mean LOS was 1.7 days longer in patients with vs those without infection; P < .001). Other independent predictors of prolonged LOS included intraoperative blood loss and reoperation in the index extremity; whereas, history of continuous preoperative aspirin use, normal renal function, and normal albumin levels were associated with decreased LOS (Table II). Readmission was influenced by the performance of a reoperation in the index extremity (OR, 2.57; P < .001) and history of diabetes (OR, 1.5; P = .023) but not the presence of foot infection (OR, 1.27; P = .192) There was a strong trend for prolonged wound healing time in patients with diabetes (HR, 1.57; P = .05), but not in those with foot infection (OR, 0.73; P = .36). Among 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 additional support to the inclusion of infection in risk-stratification schemes for patients with limb-threatening ischemia, as recommended in the Society for Vascular Surgery WIfI Classification System, because of its adverse impacts on limb salvage.Table ISignificant predictors of mortality and major amputation among those undergoing infrainguinal bypassVariableHazard ratio95% Confidence intervalP valueMortality Age1.041.02-1.07<.001 Congestive heart failure2.061.26-3.36.004 Albumin0.610.45-0.82.001 Clopidogrel0.430.25-0.74.003Major amputation Infection1.861.25-2.78.002 Age0.960.93-0.99.025 Body mass index0.940.91-0.98.014 Statin1.921.14-3.24.014 Open table in a new tab Table IISignificant predictors of postoperative length of stay (LOS) among those undergoing infrainguinal bypass (IB)VariableCoefficient95% Confidence intervalP valueInfection1.660.76-2.55<.001Glomerular filtration rate−0.02−0.043 to −0.014<.001Aspirin−1.16−2.13 to −0.18.02Albumin−1.35−2.11 to −0.60<.001Redo-open1.360.49-2.24.02Operating room estimated blood loss0.0030.001-0.004<.001 Open table in a new tab

The Increased Use of Computed Tomography Angiography and Magnetic Resonance Angiography as the Sole Imaging Modalities Prior to Infrainguinal Bypass Has Had No Effect on Outcomes

Angiography remains the gold standard imaging modality before infrainguinal bypass. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have emerged as noninvasive alternatives for preoperative imaging. We sought to examine contemporary trends in the utilization of CTA and MRA as isolated imaging modalities before infrainguinal bypass and to compare outcomes following infrainguinal bypass in patients who underwent CTA or MRA versus those who underwent conventional arteriography. Patients undergoing infrainguinal bypass within the Vascular Study Group of New England were identified (2003-2012). Patients were stratified by preoperative imaging modality: CTA/MRA alone or conventional angiography. Trends in utilization of these modalities were examined and demographics of these groups were compared. Primary end points included primary patency, secondary patency, and major adverse limb events (MALE) at 1 year as determined by Kaplan-Meier analysis. Multivariable Cox proportional hazards models were constructed to evaluate the effect of imaging modality on primary patency, secondary patency, and MALE after adjusting for confounders. In 3123 infrainguinal bypasses, CTA/MRA alone was used in 462 cases (15%) and angiography was used in 2661 cases (85%). Use of CTA/MRA alone increased over time, with 52 (11%) bypasses performed between 2003 and 2005, 189 (41%) bypasses performed between 2006 and 2009, and 221 (48%) bypasses performed between 2010 and 2012 (P < 0.001). Patients with CTA/MRA alone, compared with patients with angiography, more frequently underwent bypass for claudication (33% vs. 26%, P = 0.001) or acute limb ischemia (13% vs. 5%, P < 0.0001), more frequently had prosthetic conduits (39% vs. 30%, P = 0.001), and less frequently had tibial/pedal targets (32% vs. 40%, P = 0.002). After adjusting for these and other confounders, multivariable analysis demonstrated that the use of CTA/MRA alone was not associated with a significant difference in 1 year primary patency (hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.78-1.16), secondary patency (HR 1.30, 95% CI 0.99-1.72), or MALE (HR 1.08, 95% CI 0.89-1.32). CTA and MRA are being increasingly used as the sole preoperative imaging modality before infrainguinal bypass. This shift in practice patterns appears to have no measurable effect on outcomes at 1 year.

VESS18. Long-Term Outcomes After Open Infrainguinal Bypass in Patients With Scleroderma

VESS18. Long-Term Outcomes After Open Infrainguinal Bypass in Patients With Scleroderma

Statin therapy after infrainguinal bypass surgery for critical limb ischemia is associated with improved 5-year survival

Although statin therapy has been linked to fewer short-term complications after infrainguinal bypass, its effect on long-term survival remains unclear. We therefore examined associations between statin use and long-term mortality, graft occlusion, and amputation after infrainguinal bypass. We used the Vascular Study Group of New England registry to study 2067 patients (71% male; mean age, 67 ± 11 years; 67% with critical limb ischemia [CLI]) who underwent infrainguinal bypass from 2003 to 2011. Of these, 1537 (74%) were on statins perioperatively and at 1-year follow-up, and 530 received no statin. We examined crude, adjusted, and propensity-matched rates of 5-year surviva1, 1-year amputation, graft occlusion, and perioperative myocardial infarction. Patients taking statins at the time of surgery and at the 1-year follow-up were more likely to have coronary disease (38% vs 22%; P < .001), diabetes (51% vs 36%; P < .001), hypertension (89% vs 77%; P < .001), and prior revascularization procedures (50% vs 38%; P < .001). Despite higher comorbidity burdens, long-term survival was better for patients taking statins in crude (risk ratio [RR], 0.7; P < .001), adjusted (hazard ratio, 0.7; P = .001), and propensity-matched analyses (hazard ratio, 0.7; P = .03). In subgroup analysis, a survival advantage was evident in patients on statins with CLI (5-year survival rate, 63% vs 54%; log-rank, P = .01) but not claudication (5-year survival rate, 84% vs 80%; log-rank, P = .59). Statin therapy was not associated with 1-year rates of major amputation (12% vs 11%; P = .84) or graft occlusion (20% vs 18%; P = .58) in CLI patients. Perioperative myocardial infarction occurred more frequently in patients on a statin in crude analysis (RR, 2.2; P = .01) but not in the matched cohort (RR, 1.9; P = .17). Statin therapy is associated with a 5-year survival benefit after infrainguinal bypass in patients with CLI. However, 1-year limb-related outcomes were not influenced by statin use in our large observational cohort of patients undergoing revascularization in New England.

Infrainguinal bypass is associated with lower perioperative mortality than major amputation in high-risk surgical candidates

Major amputation is often selected over infrainguinal bypass in patients with severe systemic comorbidities because it is assumed to have lower perioperative risks, yet this assumption is unproven and largely unexamined. The 2005 to 2008 National Surgical Quality Improvement Project (NSQIP) database was used to identify all patients undergoing either infrainguinal bypass or major amputation using procedural codes. Patients with systemic or local infections were excluded. A subset of high-risk patients were then defined as American Society of Anesthesiologists (ASA) class 4 or 5, or ASA class 3 with renal failure, dyspnea at rest, ventilator dependence, recent congestive heart failure, or recent myocardial infarct. Propensity score matching was used to obtain two high-risk patient groups matched for preoperative characteristics. No significant differences in demographic, preoperative, or anesthetic variables were found between the matched, high-risk amputation or bypass groups (792 and 780 patients, respectively). Bypass was associated with a lower 30-day postoperative mortality than amputation (6.54% vs 9.97%; P = .0147). Amputation was associated with higher rates of pulmonary embolism (0.9% vs 0% for amputation vs bypass groups, respectively; P = .009) and urinary tract infection (5.2% vs 2.7%; P = .01), while bypass was associated with higher rates of return to the operating room (14.1% vs 27.6%; P < .001) and a trend toward higher postoperative transfusion requirements (0.9% vs 2.1%; P = .054). The postoperative time to discharge did not differ between the two groups. The decision to perform an infrainguinal bypass or amputation should depend on well-established predictors of graft patency and functional success rather than presumptions about different perioperative risks between the two procedures.

Estimated Glomerular Filtration Rate (eGFR) as a Predictor of Outcome after Infrainguinal Bypass in Patients with Critical Limb Ischemia

Objectives Renal insufficiency is a risk factor for poor outcome after infrainguinal bypass in patients with critical limb ischemia (CLI). Estimated glomerular filtration rate (eGFR) takes age, gender and body size into account and therefore represents actual renal function more accurately than serum creatinine level alone. The aim of this study was to determine the impact of different stages of renal insufficiency on outcome and to assess the prognostic significance of eGFR in patients with CLI. Material and methods 603 patients with CLI who underwent infrainguinal bypass between January 2002 and December 2005 at our institution were included in this retrospective study. We estimated GFR using the Modification of Diet in Renal Disease (MDRD) Study equation. Survival, leg salvage and amputation-free survival were calculated using Kaplan–Meier method. Cox regression analysis was performed to calculate hazard ratios for different outcome variables. Results Adjusted hazard ratio (HR) of mortality, limb loss and limb loss and/or death for eGFR <30 ml/min/1.73 m 2 versus serum creatinine >200 μmol/l was 4.0 (95% CI 2.22–7.39) vs 3.5 (95% CI 1.82–6.84), 6.5 (95% CI 2.71–15.59) vs 6.2 (95% CI 2.47–15.56) and 4.0 (95% CI 2.40–6.63) vs 3.6 (95% CI 2.03–6.25), respectively. Conclusion Estimated GFR is better predictor of survival, leg salvage and amputation-free survival than serum creatinine alone. eGFR <30 ml/min/1.73 m 2 is independent risk factor for all three outcome endpoints.

Contemporary Analysis of Outcomes following Lower Extremity Bypass in Patients with End-stage Renal Disease

This study was designed to compare outcomes following infrainguinal bypass between patients with end-stage renal disease (ESRD) and patients with normal renal function (NRF). Sixty-three patients with ESRD undergoing 78 infrainguinal bypasses from 1990 to 1999 were compared with a concurrent group of 132 age-, race-, and gender-matched patients with NRF undergoing 148 bypasses. Limb salvage and survival were calculated using Kaplan-Meier analysis. Markov decision analysis was used to calculate expected quality-adjusted life years (QALY) with intervention. Mean follow-up was 25 months (range 1-116). The results of our study show that infrainguinal bypass in patients with ESRD and tissue necrosis appears to provide a measurable, but marginal, degree of improvement in quality of life.