Risk score for one-year mortality following emergent infra-inguinal bypass.

OBJECTIVE: The purpose of this study is to identify variables that place patients at higher risk for mortality following emergent infra-inguinal bypass. Further, this study will create a risk score for mortality following emergent infra-inguinal bypass to help tailor postoperative and long-term patient management. METHODS: In the Vascular Quality Initiative, we identified 2126 patients who underwent emergent infra-inguinal artery bypass. Two primary outcomes were investigated: 30 day mortality following emergent infra-inguinal bypass; and 1-year mortality following emergent infra-inguinal bypass. The first step in analysis was univariable analysis for each outcome with χ2 analysis for categorical variables and Student t-test for comparison of means of ordinal variables. Next, binary logistic regression analysis was performed for each outcome utilizing variables that achieved a univariable P value ≤ .10. Factors with a multivariable P value ≤ .05 were included in the risk score, and points were weighted and assigned based on the respective regression beta-coefficient in the multivariable regression. RESULTS: Variables with a significant multivariable association (P < .05) with 1-year mortality were: increasing age; body mass index less than 20 kg/m2; coronary artery disease; active hemodialysis at time of presentation; anemia at admission; prosthetic conduit for emergent bypass; postoperative myocardial infarction; postoperative acute renal insufficiency; perioperative stroke; baseline non-ambulatory status; new onset hemodialysis requirement perioperatively; need for bypass revision or thrombectomy during index admission; lack of statin prescription at discharge; lack of antiplatelet medication at discharge; and, lack of anticoagulation at time of hospital discharge. Pertinent negatives included all sociodemographic variables including rural living status, insurance status, and Area Deprivation Index home area. The risk score achieved an area under the curve of 0.820, and regression analysis of the risk score achieved an overall accuracy of 87.9% with 97.7% accuracy in predicting survival, indicating the model performs better in determining which patients will survive rather than precisely determining who will experience 1-year mortality. CONCLUSIONS: Discharge medications are the primary modifiable variable impacting survival after emergent infra-inguinal bypass surgery. In the absence of contraindication, all these patients should be discharged on antiplatelet, statin, and anticoagulant medications after emergent infra-inguinal bypass as they significantly enhance survival. Social determinants of health do not impact survival among patients treated with emergent infra-inguinal bypass at Vascular Quality Initiative centers. A risk score for mortality at 1 year after emergent infra-inguinal bypass has been created that has excellent accuracy.

Socioeconomic disadvantage is a leading variable in risk score for major amputation following emergent infrainguinal arterial bypass surgery.

OBJECTIVE: The purpose of this study was to identify patients at particularly high risk for major amputation after emergent infrainguinal bypass to help tailor postoperative and long-term patient management. METHODS: In the Vascular Quality Initiative, we identified 2126 patients who underwent emergent infrainguinal artery bypass. Two primary outcomes were investigated: major ipsilateral amputation above the ankle level during the index hospitalization and major amputation above the ankle at any time after emergent infrainguinal bypass surgery (perioperative and postdischarge combined). Binary logistic regression analysis was performed for each outcome using variables that achieved a univariable P value of ≤.10. We then determined which variables have a multivariable association for the outcomes as defined by a regression P value of ≤.05. A risk score was then created for the outcome of amputation after emergent infrainguinal bypass using weighted beta-coefficient. Variables with a multivariable P value of ≤.05 were included in the risk score and weighted based on their respective regression beta-coefficient in a point scale. RESULTS: Overall, 17.1% of patients (368/2126) underwent major amputation at some point in follow-up after emergent infrainguinal artery bypass. The mean follow-up duration on the amputation variable was 261 days with the end point being time of amputation or time of last follow-up data on the amputation variable. Variables with a significant multivariable association (P < .05) with major amputation at any point after emergent infrainguinal arterial bypass were home status in top 10% (most deprived) of Area Deprivation Index, prior infrainguinal ipsilateral arterial bypass, prior ipsilateral endovascular arterial intervention, prosthetic bypass conduit, postoperative skin/soft tissue infection, and postoperative need to revise or thrombectomize bypass. Pertinent negatives on multivariable analysis included all baseline comorbidities, insurance status, race, and gender. There is steep progression in amputation rate ranging from 5% at scores of 0 and 1 to >60% for scores in of >10. Area under the curve analysis revealed a value of 0.706. CONCLUSIONS: Patients living in the most disadvantaged socioeconomic neighborhoods have an increased risk of amputation after emergent infrainguinal arterial bypass independent of baseline comorbidities and perioperative events. Baseline comorbidities are not impactful regarding amputation rates after emergent infrainguinal bypass surgery. The need for bypass revision or thrombectomy during the index hospitalization is the most impactful factor toward amputation after emergency bypass. A risk score with quality accuracy has been developed to help identify patients at particularly high likelihood of limb loss, which may aid in counseling regarding heightened vigilance in postoperative and long-term follow-up care.

Multicenter parallel randomized trial evaluating incisional negative pressure wound therapy for the prevention of surgical site infection after lower extremity bypass.

OBJECTIVE: Incisional negative pressure wound therapy (iNPWT) applied over all incisions after lower extremity bypass in the prevention of surgical site infections (SSIs) is unclear. The primary and secondary aims of this study were to investigate if prophylactic iNPWT after the elective lower extremity bypass prevents SSI and other surgical wound complications. METHODS: This was a multicenter, parallel, randomized controlled trial. Patients undergoing elective lower extremity bypass in 3 hospitals were randomized to either iNPWT or standard dressings. SSIs or other wound complications were assessed within the first 90 days by wound care professionals blinded to the randomized result. The validated Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of deep tissues, Isolation of bacteria, and Stay (ASEPSIS) score was used to objectively assess the wounds. ASEPSIS score ≥21 is defined as an SSI. Unilateral and bilateral groups were analyzed with the Fisher exact test and the McNemar test, respectively. RESULTS: In the unilateral group (n = 100), the incidence of SSI in the iNPWT group was 34.9% (15/43), compared with 40.3% (23/57) in the control group, according to the ASEPSIS score (P = .678). In the bilateral group (n = 7), the SSI rate was 14.3% (1/7) in the iNPWT group compared with 14.3% (1/7) in the control group (P = 1.00). In the unilateral group, there was a higher wound dehiscence rate in the control group (43.9%) compared with the iNPWT group (23.3%) (P = .0366). No serious iNPWT-related adverse events were recorded. CONCLUSIONS: There was no reduction of SSI rates in leg incisions with iNPWT compared with standard dressings in patients undergoing elective lower extremity bypass, whereas iNPWT reduced the incidence of wound dehiscence.

Long-term outcomes of great saphenous vein harvest techniques for infrainguinal arterial bypass in a Medicare-matched registry database.

OBJECTIVE: Long-term outcomes for harvesting techniques for great saphenous vein (GSV) and its impact on the outcomes of infrainguinal arterial bypass remains largely unknown. Endoscopic GSV harvesting (EVH) has emerged as a less invasive alternative to conventional open techniques. Using the Vascular Quality initiative Vascular Implant Surveillance & Interventional Outcomes Network (VQI-VISION) database, we compared the long-term outcomes of infrainguinal arterial bypass using open and endoscopic GSV harvest techniques. METHODS: Patients who underwent infrainguinal GSV bypass between 2010 and 2019 were identified in the VQI-VISION Medicare linked database. Long-term outcomes of major/minor amputations, and reinterventions up to 5 years of follow-up were compared between continuous incisions, skip incision, and EVH, with continuous incisions being the reference group. Secondary outcomes included 30- and 90-day readmission, in addition to surgical site infections and patency rates at 6 months to 2 years postoperatively. Survival analysis using Kaplan-Meier curves and Cox regression hazard models were utilized to compare outcomes between groups. To adjust for multiple comparisons between the study groups, a P value of 2.5% was considered significant. RESULTS: Among the 8915 patients included in the study, continuous and skip vein harvest techniques were used in 44.4% and 43.4% of cases each, whereas 12.3% underwent EVH. The utilization of EVH remained relatively stable at around 12% throughout the study period. Compared with GSV harvest using continuous incisions, EVH was associated with higher rates of reintervention at 1 year (46.5% vs 41.3%; adjusted hazard ratio [aHR], 1.22; 95% confidence interval [CI], 1.06-1.41; P = .01]. However, no significant difference was observed between EVH and continuous incisions, and between skip and continuous incisions in terms of long-term reintervention or major and minor amputations on adjusted analysis. Compared with continuous incision vein harvest, both EVH and skip incisions were associated with lower surgical site infection rates within the first 6 months post-bypass (aHR, 0.53; 95% CI, 0.35-0.82 and aHR, 0.68; 95% CI, 0.53-0.87, respectively). Loss of primary, primary-assisted, and secondary patency was higher after EVH compared with continuous incision vein harvest. Among surgeons performing EVH, comparable long-term outcomes were observed regardless of low (<4 cases/year), medium (4-7 cases/year), or high procedural volumes (>7 cases/year). CONCLUSIONS: Despite higher 1-year reintervention rates, EVH for infrainguinal arterial bypass is not associated with a significant difference in long-term reintervention or amputation rates compared with other harvesting techniques. These outcomes are not influenced by procedural volumes for EVH technique.

DETOUR2 trial outcomes demonstrate clinical utility of percutaneous transmural bypass for the treatment of long segment, complex femoropopliteal disease.

OBJECTIVE: Percutaneous transmural arterial bypass (PTAB) using the DETOUR system aims to create a percutaneous, endovascular femoropopliteal bypass for the treatment of long segment, complex superficial femoral and proximal popliteal artery disease. The goal of the DETOUR2 study is to investigate the safety and effectiveness of the therapy in comparison with pre-established performance goals. METHODS: The DETOUR2 investigational device exemption study is a prospective, single-arm, multicenter, international trial of symptomatic peripheral arterial disease patients (Rutherford classes 3-5) undergoing the DETOUR procedure for long segment (>20 cm) superficial femoral artery disease. Prespecified end points included primary safety (composite of major adverse events) at 30 days, and effectiveness (primary patency defined as freedom from restenosis or clinically driven target lesion revascularization) at 1 year. RESULTS: We enrolled 202 patients at 32 sites with 200 treated with the DETOUR system. The mean lesion length was 32.7 cm, of which 96% were chronic total occlusions (CTO) and 70% were severely calcified. Technical success was achieved in 100% of treated patients. The primary safety end point was met with a 30-day freedom from major adverse event rate of 93.0%. The 1-year primary effectiveness end point was met with 72.1% primary patency at 12 months. Primary-assisted and secondary patency were 77.7% and 89.0%, respectively, at 12 months. The 12 month deep venous thrombosis incidence was 4.1% with no pulmonary emboli reported. Venous quality-of-life scores showed no significant changes from baseline. There was a Rutherford improvement of at least one class through 12 months in 97.2% of patients. The mean ankle-brachial index also improved from 0.61 to 0.95 during this period. There were marked improvements in quality-of-life and functional status measures. CONCLUSIONS: The DETOUR2 study met both the primary safety and effectiveness end points, demonstrating clinical usefulness of this novel therapeutic strategy in long femoropopliteal lesions.

Polyvascular disease is common in patients undergoing carotid endarterectomy and lower extremity bypass and is associated with worse outcomes.

BACKGROUND: Polyvascular disease is strongly associated with increased risk of cardiovascular morbidity and mortality. However, its prevalence in patients undergoing carotid and lower extremity surgical revascularization and its impact on outcomes are unknown. METHODS: The Vascular Quality Initiative was queried for carotid endarterectomy (CEA) or infrainguinal lower extremity bypass (LEB), 2013-2019. Polyvascular disease was defined as presence of atherosclerotic occlusive disease in more than one arterial bed: carotid, coronary, and infrainguinal. Primary outcomes were (1) composite perioperative myocardial infarction (MI) or death and (2) 5-year survival. Patient characteristics and perioperative outcomes were evaluated using the χ2 test and multivariable logistic regression. Survival was analyzed using Kaplan-Meier method and Cox proportional hazards multivariable models. RESULTS: Polyvascular disease was identified in 47% of CEA (39.0% in 2 arterial beds, 7.6% in 3 arterial beds; n = 93,736) and 47% of LEB (41.0% in 2 arterial beds, 5.7% in 3 arterial beds; n = 25,223). For both CEA and LEB, patients with polyvascular disease had more comorbidities including hypertension, congestive heart disease, chronic obstructive pulmonary disease, smoking, diabetes mellitus, and end-stage renal disease (P < .0001). Perioperative MI/death rates increased with increasing number of vascular beds affected following CEA (0.9% in 1 bed vs 1.5% in 2 beds vs 2.7% in 3 beds; P < .001) and LEB (2.2% in 1 bed vs 5.3% in 2 beds vs 6.6% in 3 beds; P < .001). Polyvascular disease was associated independently with perioperative MI/death after CEA (odds ratio, 1.59; 95% confidence interval [CI], 1.40-1.81;P < .0001) and LEB (odds ratio, 1.78; 95% CI, 1.52-2.08; P < .0001). Five-year survival was decreased in patients with polyvascular disease after CEA (82% in 3 beds vs 88% in 2 beds vs 92% in 1 bed; P < .01) and LEB (72% in 3 beds vs 75% in 2 beds vs 84% in 1 bed; P < .01) in a dose-dependent manner, with the lowest 5-year survival observed in those with three arterial beds involved. Polyvascular disease was independently associated with 5-year mortality after CEA (hazard ratio, 1.33; 95% CI, 1.24-1.40; P = .0001) and LEB (hazard ratio, 1.30; 95% CI, 1.20-1.41; P = .0001). CONCLUSIONS: Polyvascular disease is common in patients undergoing CEA and LEB and is associated with a higher risk of perioperative MI/death and decreased long-term survival. After revascularization, patients with polyvascular disease should be considered for more aggressive cardioprotective medications and closer follow-up.

Clinical factors associated with ultrashort length of stay in patients undergoing lower extremity bypass for peripheral arterial disease.

BACKGROUND: Length of stay (LOS) is a major driver of cost and resource utilization following lower extremity bypass (LEB). However, the variable comorbidity burden and mobility status of LEB patients makes implementing enhanced recovery after surgery pathways challenging. The aim of this study was to use a large national database to identify patient factors associated with ultrashort LOS among patients undergoing LEB for peripheral artery disease. METHODS: All patients undergoing LEB for peripheral artery disease in the National Surgical Quality Improvement Project database from 2011 to 2018 were included. Patients were divided into two groups based on the postoperative length of stay : ultrashort (≤2 days) and standard (>2 days). Thirty-day outcomes were compared using descriptive statistics, and multivariable logistic regression was used to identify patient factors associated with ultrashort LOS. RESULTS: Overall, 17,510 patients were identified who underwent LEB, of which 2678 patients (15.3%) had an ultrashort postoperative LOS (mean, 1.8 days) and 14,832 (84.7%) patients had a standard LOS (mean, 7.1 days). When compared to patients with a standard LOS, patients with an ultrashort LOS were more likely to be admitted from home (95.9% vs 88.0%; P < .001), undergo elective surgery (86.1% vs 59.1%; P < .001), and be active smokers (52.1% vs 40.4%; P < .001). Patients with an ultrashort LOS were also more likely to have claudication as the indication for LEB (53.1% vs 22.5%; P < .001), have a popliteal revascularization target rather than a tibial/pedal target (76.7% vs 55.3%; P < .001), and have a prosthetic conduit (40.0% vs 29.9%; P < .001). There was no significant difference in mortality between the two groups (1.4% vs 1.8%; P = .21); however, patients with an ultrashort LOS had a lower frequency of unplanned readmission (10.7% vs 18.8%; P < .001) and need for major reintervention (1.9% vs 5.6%; P < .001). On multivariable analysis, elective status (odds ratio , 2.66; 95% confidence interval [CI], 2.33-3.04), active smoking (OR, 1.18; 95% CI, 1.07-1.30), and lack of vein harvest (OR, 1.55; 95% CI, 1.41-1.70) were associated with ultrashort LOS. Presence of rest pain (OR, 0.57; 95% CI, 0.51-0.63), tissue loss (OR, 0.30; 95% CI, 0.27-0.34), and totally dependent functional status (OR, 0.54; 95% CI, 0.35-0.84) were associated negatively with an ultrashort LOS. When examining the subgroup of patients who underwent vein harvest, totally dependent (OR, 0.38; 95% CI, 0.19-0.75) and partially dependent (OR, 0.53; 95% CI, 0.32-0.88) functional status were persistently negatively associated with ultrashort LOS. CONCLUSIONS: Ultrashort LOS (≤2 days) after LEB is uncommon but feasible in select patients. Preoperative functional status and mobility are important factors to consider when identifying LEB patients who may be candidates for early discharge.

Secondary interventions following open vs endovascular revascularization for chronic limb threatening ischemia in the BEST-CLI trial.

OBJECTIVES: Patients undergoing revascularization for chronic limb-threatening ischemia experience a high burden of target limb reinterventions. We analyzed data from the Best Endovascular versus Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) randomized trial comparing initial open bypass (OPEN) and endovascular (ENDO) treatment strategies, with a focus on reintervention-related study endpoints. METHODS: In a planned secondary analysis, we examined the rates of major reintervention, any reintervention, and the composite of any reintervention, amputation, or death by intention-to-treat assignment in both trial cohorts (cohort 1 with suitable single-segment great saphenous vein [SSGSV], n = 1434; cohort 2 lacking suitable SSGSV, n = 396). We also compared the cumulative number of major and all index limb reinterventions over time. Comparisons between treatment arms within each cohort were made using univariable and multivariable Cox regression models. RESULTS: In cohort 1, assignment to OPEN was associated with a significantly reduced hazard of a major limb reintervention (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.28-0.49; P < .001), any reintervention (HR, 0.63; 95% CI, 0.53-0.75; P < .001), or any reintervention, amputation, or death (HR, 0.68; 95% CI, 0.60-0.78; P < .001). Findings were similar in cohort 2 for major reintervention (HR, 0.53; 95% CI, 0.33-0.84; P = .007) or any reintervention (HR, 0.71; 95% CI, 0.52-0.98; P = .04). In both cohorts, early (30-day) limb reinterventions were notably higher for patients assigned to ENDO as compared with OPEN (14.7% vs 4.5% of cohort 1 subjects; 16.6% vs 5.6% of cohort 2 subjects). The mean number of major (mean events per subject ratio [MR], 0.45; 95% CI, 0.34-0.58; P < .001) or any target limb reinterventions (MR, 0.67; 95% CI, 0.57-0.80; P < .001) per year was significantly less in the OPEN arm of cohort 1. The mean number of reinterventions per limb salvaged per year was lower in the OPEN arm of cohort 1 (MR, 0.45; 95% CI, 0.35-0.57; P < .001 and MR, 0.66; 95% CI, 0.55-0.79; P < .001 for major and all, respectively). The majority of index limb reinterventions occurred during the first year following randomization, but events continued to accumulate over the duration of follow-up in the trial. CONCLUSIONS: Reintervention is common following revascularization for chronic limb-threatening ischemia. Among patients deemed suitable for either approach, initial treatment with open bypass, particularly in patients with available SSGSV conduit, is associated with a significantly lower number of major and minor target limb reinterventions.

Open Surgical Therapy for Peripheral Artery Disease.

PURPOSE OF REVIEW: The surgical management of symptomatic peripheral artery disease (PAD) has changed in the last few decades. Improvement in endovascular technology has resulted in more complex lesion once reserved for open surgery being addressed in an endovascular fashion. Even with these advances, there are lesions and patients that are better managed with an open surgical procedure. The aim of this review is to describe the most commonly performed open surgical procedures for PAD. RECENT FINDINGS: The recently published Best Endovascular versus Best Surgical Therapy (BEST-CLI) trial was an international, prospective, randomized controlled trial that aimed to investigate which revascularization (endovascular vs. surgical bypass) approach was superior for limb salvage. The evidence supports an open surgical bypass as an initial approach. The advancements made in the surgical management of PAD have provided options for patients who were once deemed poor surgical candidates. The goal continues to be utilization of the best available tools to address patient disease. In this current era, it is important to be familiar with the open surgical therapies.

Long-term outcomes after lower extremity bypass in the actively smoking claudicant.

OBJECTIVE: Smoking is known to increase complications, including poor wound healing, coagulation abnormalities, and cardiac and pulmonary ramifications. Across specialties, elective surgical procedures are commonly denied to active smokers. Given the base population of active smokers with vascular disease, smoking cessation is encouraged but is not required the way it is for elective general surgery procedures. We aim to study the outcomes of elective lower extremity bypass (LEB) in actively smoking claudicants. METHODS: We queried the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network LEB database from 2003 to 2019. In this database we found 609 (10.0%) never smokers (NS), 3388 (55.3%) former smokers (FS), and 2123 (34.7%) current smokers (CS) who underwent LEB for claudication. We performed two separate propensity score matches without replacement on 36 clinical variables (age, gender, race, ethnicity, obesity, insurance, hypertension, diabetes, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, chronic kidney disease, previous coronary artery bypass graft, carotid endarterectomy, major amputation, inflow treatment, preoperative medications and treatment type), one of FS to NS and a second analysis of CS to FS. Primary outcomes included 5-year overall survival (OS), limb salvage (LS), freedom from reintervention (FR), and amputation-free survival (AFS). RESULTS: Propensity score matches resulted in 497 well-matched pairs of NS and FS. In this analysis we found no difference in terms of OS (HR, 0.93; 95% CI, 0.70-1.24; P = .61), LS (HR, 1.07; 95% CI, 0.63-1.82; P = .80), FR (HR, 0.9; 95% CI,0.71-1.21; P = .59), or AFS (HR, 0.93; 95% CI,0.71-1.22; P = .62). In the second analysis, we had 1451 well-matched pairs of CS and FS. There was no difference in LS (HR, 1.36; 95% CI,0.94-1.97; P = .11) or FR (HR, 1.02; 95% CI,0.88-1.19; P = .76). However, we did find a significant increase in OS (HR, 1.37; 95% CI,1.15-1.64, P <.001) and AFS (HR, 1.38; 95% CI,1.18-1.62; P < .001) in FS compared with CS. CONCLUSIONS: Claudicants represent a unique nonemergent vascular patient population that may require LEB. Our study found that FS have better OS and AFS when compared with CS. Additionally, FS mimic nonsmokers at 5-year outcomes for OS, LS, FR, and AFS. Therefore, structured smoking cessation should be a more prominent part of vascular office visits before elective LEB procedures in claudicants.

Limb salvage in octogenarians with critical limb ischemia after lower extremity bypass surgery.

OBJECTIVES: Peripheral artery disease is a worldwide epidemic that affects millions of patients, especially the elderly. It has a prevalence of 20% in individuals >80 years old. Although peripheral artery disease affects >20% of octogenarians, information about limb salvage rates in this patient population is limited. Therefore, this study aims to understand the impact of bypass surgery on limb salvage in patients aged >80 years with critical limb ischemia. METHODS: We conducted a retrospective analysis by querying the electronic medical records at a single institution from 2016 through 2022 to identify the population of interest and analyzed their outcomes after lower extremity bypass. The primary outcomes were limb salvage and primary patency, with hospital length of stay and 1-year mortality as secondary outcomes. RESULTS: We identified 137 patients who met the inclusion criteria. The lower extremity bypass population was divided into two cohorts: <80 years old (n = 111) with a mean age of 66 or ≥80 years old (n = 26) with a mean age of 84 years. The gender distribution was similar (P = .163). No significant difference was found in the two cohorts when it came to coronary artery disease, chronic kidney disease, or diabetes mellitus. However, when current and former smokers were grouped together, they were significantly more common in the younger cohort when compared with nonsmokers (P = .028). The primary end point of limb salvage was not significantly different between the two cohorts. Hospital length of stay was not significantly different between the two cohorts with 4.13 days vs 4.17 days in the younger vs octogenarian cohorts, respectively (P = .95). The 30-day all-cause readmissions were also not found to be significantly different between the two groups. The primary patency at 1 year was 75% and 77% (P = .16) for the <80-year-old and ≥80-year-old cohorts, respectively. Mortality was low in both cohorts, with two and three for the younger and octogenarian populations, respectively; thus, no analysis was performed. CONCLUSIONS: Our study shows that octogenarians who undergo the same preoperative risk assessment as younger populations have similar outcomes when it comes to primary patency, hospital length of stay, and limb salvage when comorbidities were considered. Further studies need to be done to determine the statistical impact on mortality in this population with a larger cohort.

Investigating glycemic control in patients undergoing lower extremity bypass within an enhanced recovery pathway at a single institution.

BACKGROUND: Enhanced recovery pathways (ERPs) aim to lower perioperative stress to facilitate recovery. Limited fasting combined with carbohydrate loading is a common ERP element. The effect of limited fasting has not been elucidated in patients with diabetes. Given the known deleterious effects of poor glycemic control in the perioperative period, such as increased rates of surgical site infection, the associations of preoperative limited fasting with perioperative glycemic control and early outcomes after lower extremity bypass (LEB) were investigated. METHODS: A single institutional retrospective review of patients who underwent infrainguinal LEB from 2016 to 2022 was performed. The ERP was initiated in May 2018. Patients were stratified by diabetes diagnosis and preoperative hemoglobin A1C (HbA1C) levels. Perioperative glycemic control was compared between the limited fasting and traditional fasting patients (nil per os at midnight). Limited fasting was defined as a clear liquid diet until 2 hours before surgery with recommended carbohydrate loading consisting of 400 cc of a clear sports drink (approximately 30 g of carbohydrates). All limited fasting patients were within the ERP. Early perioperative hyperglycemia (EPH) was defined as blood glucose of >180 mg/dL within the first 24 hours of surgery. Perioperative outcomes such as surgical site infection, readmission, reinterventions, and complications were also compared. RESULTS: A total of 393 patients were included (limited fasting patients N = 135; traditional fasting patients N = 258). A trend toward EPH was seen in all limited fasting groups. Evaluating limited fasting within diabetic patients revealed that 74.5% of limited fasting-diabetic patients had EPH compared with 49.6% of traditional fasting-diabetic patients (P = .001). When stratified by the HbA1C level, a significantly higher rate of EPH was seen in the HbA1c >8.0% groups, with 90.5% in the limited fasting patients compared with 67.9% in traditional fasting patients (P = .05). Limited fasting-diabetic patients experience a longer postoperative length of stay at 5.0 days (interquartile range: 3, 9) vs 4.0 days (2, 6) in nondiabetic patients (P = .016). CONCLUSIONS: ERP limited fasting was associated with early perioperative hyperglycemia after LEB, particularly in patients with HbA1C >8.0%. Due to the high prevalence of diabetic patients undergoing LEB under ERP, the role of limited fasting and common glycemic elements of ERP may need to be re-evaluated in this subpopulation.

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

INTRODUCTION: 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. METHODS: 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. RESULTS: 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]). CONCLUSION: 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.

Postoperative decline in ambulatory function after lower extremity bypass is associated with higher short- and long-term mortality.

OBJECTIVE: Although the importance of preexisting functional and ambulatory status among patients undergoing lower extremity bypass (LEB) has been increasingly recognized, a paucity of reported data is available on the significance of a postoperative decline in ambulatory status after LEB surgery. The purpose of the present analysis was to determine the effects of a new decline in ambulatory status after LEB surgery on the postoperative short- and long-term outcomes. METHODS: The Vascular Quality Initiative infrainguinal bypass dataset was queried from 2003 to 2021 for patients with peripheral arterial disease (PAD) who had undergone LEB. Information on ambulatory status at admission and discharge from the hospital was recorded. Patients with a decline in ambulatory status at discharge from the hospital were included in group I, and those who had maintained their ambulatory status at discharge were included in group II. The primary outcomes were mortality, amputation, and a composite outcome of mortality or amputation at 30 days and 1 year postoperatively. The secondary outcomes were major adverse cardiovascular events, myocardial infarction, congestive heart failure, stroke, dysrhythmia, pneumonia, and the need for prolonged ventilation. RESULTS: A total of 40,478 patients were included in the present study, of whom 16,032 (39.6%) were included in group I and 24,446 (60.4%) were included in group II. The patients in group I were more often aged >70 years, women, African American, transferred from another hospital or rehabilitation facility, prior or current smokers, or had an American Society of Anesthesiologists classification of III or IV compared with those with unchanged ambulatory status (P < .05 for all). Patients with a decline in ambulatory status had had a greater incidence of mortality at 30 days (2.4% vs 0.6%; P < .001) and 1 year (9.7% vs 7%; P < .001) postoperatively. Patients with a decline in ambulatory status had had a greater occurrence of major adverse cardiovascular events, myocardial infarction, stroke, dysrhythmia, and the need for prolonged ventilation. The following factors were associated with a decline in postoperative ambulatory status: older age (70-79 years: adjusted odds ratio [aOR], 1.20; 95% confidence interval [CI], 1.07-1.34; P = .001; and ≥80 years: aOR, 1.18; 95% CI, 1.05-1.35; P = .007), female sex (aOR, 1.06; 95% CI, 1.00-1.11; P = .019), African-American race (aOR, 1.15; 95% CI, 1.07-1.21; P < .001), transfer from another hospital or rehabilitation unit (aOR, 1.30; 95% CI, 1.18-1.41; P < .001), and a history of diabetes mellitus (aOR, 1.12; 95% CI, 1.06-1.17; P = .004). The magnitude of decline in ambulatory function was associated with worse primary outcomes. Patients whose ambulatory function had declined from ambulatory to bedridden after LEB surgery had had the highest mortality (aOR, 21 at 30 days and 15 at 1 year). CONCLUSIONS: A new decline in ambulatory function at discharge from the hospital after LEB surgery was associated with increased short- and long-term mortality and the composite outcome of mortality or amputation. It was also associated with reduced amputation-free survival at 30 days and 1 year postoperatively.

Hemoglobin A1c monitoring practices before lower extremity bypass in patients with diabetes vary broadly and do not predict outcomes.

OBJECTIVE: Hemoglobin A1c (HbA1c) is used as a marker of glycemic control, but the role of HbA1c before lower extremity bypass (LEB) in patients with diabetes remains unclear. We sought to characterize patients with diabetes undergoing LEB with and without HbA1c monitoring and to determine if HbA1c monitoring practices correlate with better outcomes. METHODS: The Vascular Quality Initiative was queried for all LEB in patients with diabetes (2010-2020). Patients with diabetes were characterized based on therapy: diet-controlled, noninsulin medication use, or insulin use. Glycemic control was characterized by preoperative HbA1c within 6 months of surgery: unknown control (no HbA1c), well-controlled (HbA1c <7%), poorly-controlled (HbA1c 7%-10%), and uncontrolled (HbA1c >10%). Centers with >5 LEB/y were stratified into terciles according to rate of HbA1c monitoring. The unadjusted associations between glycemic control and in-hospital major adverse limb events, major adverse cardiac events, and mortality were assessed with univariate methods. The independent association of center-level HbA1c monitoring with 5-year survival and 3-year amputation-free survival (AFS) was determined with Kaplan-Meier analyses and Cox regression modeling, adjusted for differences in patient characteristics and center volume. RESULTS: Of 16,092 patients with diabetes undergoing LEB, 4055 (25%) did not have a documented HbA1c. Insulin use was less common in no A1c (48%) and well-controlled diabetes (39%) compared with poorly controlled (67%) and uncontrolled diabetes (78%) (P < .01). In univariate analyses, glycemic control was not associated with differences for in-hospital major adverse limb events, major adverse cardiac events, or mortality. Of 162 centers, HbA1c monitoring practices varied widely (range: 12.5%-100% of LEB). The 3-year AFS and 5-year survival were worse in the highest monitoring tercile vs the lowest (73.6% vs 77.3%, P < .01, 72.1% vs 77.5%, P < .01, respectively). On multivariable analyses, centers in the highest tercile of monitoring had the greatest hazard of AFS (hazard ratio: 1.21, 95% confidence interval: 1.1-1.3, P < .001) and overall mortality (hazard ratio: 1.19, 95% confidence interval: 1.1-1.3, P < 0.001), compared with the centers in the lowest tercile of monitoring. CONCLUSIONS: Patients with diabetes and no preoperative HbA1c monitoring do not have worse LEB outcomes compared with those with HbA1c monitoring. Preoperative HbA1c monitoring varies widely, suggesting broad differences in practice and documentation. Centers with the highest rates of monitoring demonstrated inferior outcomes, likely due to other confounding unmeasured variables. These findings indicate that HbA1c monitoring before LEB, unto itself, should not be used as a measure of surgical quality.

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. METHODS: The 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. RESULTS: We 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. CONCLUSIONS: In 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.

Surgical site infection after open lower extremity revascularization associated with doubled rate of major limb amputation.

OBJECTIVE: Surgical site infection (SSI) after open lower extremity revascularization is a relatively common complication associated with increased hospital stays, graft infection, and in severe cases, graft loss. Although the short-term effects of SSI can be significant, it has not been considered a complication that increases major limb amputation. The purpose of this study was to determine the association of SSI with outcomes in patients undergoing surgical revascularization for peripheral arterial disease. METHODS: We analyzed nationwide Vascular Quality Initiative (VQI) data from the infrainguinal bypass module from 2003 to 2017. The cohort included adults who underwent open lower extremity bypass for symptomatic peripheral arterial disease and had at least one follow-up record. Weighted Kaplan-Meier curves and Cox proportional hazards regression were used to assess the association between SSI and 1-year mortality and major limb amputation. Inverse-probability of treatment weights were used to account for differences in demographics and patient characteristics and allow for 'adjusted' Kaplan-Meier curves. RESULTS: The analysis included 21,639 patients, and 1155 (5%) had a reported SSI within 30 days of surgery. Patients with SSI were more likely be obese (41% vs 30%), but there were no other clinically relevant differences between demographics, comorbidities, and bypass details. After weighting, patients with SSI were almost twice as likely to undergo major amputation by 6 months (hazard ratio, 1.84; 95% confidence interval, 1.07-3.17). The association with SSI and increased amputation rates persisted at 1 year. The association of SSI on amputation was no different based on preoperative Rutherford class (P = .91). The association between SSI and 1-year mortality rate was not statistically significant (hazard ratio, 1.15; 95% confidence interval, 0.91-1.46). CONCLUSIONS: SSI is more common in obese patients, and patients who develop an SSI are observed to have a significantly increased rate of limb amputation after open lower extremity revascularization.

Ten-year experience of infrainguinal bypass with endoscopic vein harvest.

OBJECTIVES: There is conflicting data comparing minimally invasive vein harvest (MIVH) using endoscopic technique and open vein harvest (OVH) in terms of bypass patency, wound infection incidence, and patient morbidity. Our institution has performed MIVH since 2003 for peripheral bypass procedures with a consistent team of specialized endoscopic vein harvesters. This study reviewed the major outcomes of MIVH infrainguinal bypass at our institution given a predominant cohort of critical limb ischemia. METHODS: We performed a 10-year, retrospective, single-institution review from January 2005 to December 2014, identifying all patients undergoing MIVH for obstructive infrainguinal disease. Primary outcomes were primary patency, operative time, intraoperative complications, surgical site infection (SSI), and freedom from amputation. RESULTS: A total of 289 patients (70% male) underwent MIVH infrainguinal bypass at an average age of 68 ± 12 years old, an obesity prevalence of 28%, and with critical limb ischemia in 81% of the patient cohort (20% rest pain, 61% tissue loss/gangrene). Ninety-four percent of patients had no intraoperative complications, 2.5% had adverse cardiac or technical complications, and 4.2% of patients required transfusion. Average operative time was 4.2 h. Femoral-popliteal TASC classification C and D constituted 80% of our patient cohort. At the last follow-up, toe pressures had increased from 30 ± 30 to 62 ± 40 mmHg (p < 0.0001). Primary bypass patency in the first 30 days was 95%. SSI incidence requiring surgical treatment was only 6%. Our median length of stay was 4.0 days, with median intravenous narcotic use of 1 day. In addition, 77% of patients returned to their baseline mobility at first follow-up (median 19 days), and 83% of patients had freedom from amputation at last follow-up (median 820 days). CONCLUSIONS: In a center with experience in MIVH and a consistent group of experienced endoscopic vein harvesters, MIVH bypass has excellent patency, low surgical site infection, short length of stay, and prompt return to baseline mobility.

Surgeon experience versus volume differentially affects lower extremity bypass outcomes in contemporary practice.

BACKGROUND: Calls for minimum case thresholds to guide surgeon credentialing paradigms are increasing in contemporary practice. To date, the volume-outcome relationship and the role of surgeon experience as a proxy for quality have remained primarily focused on nonvascular extirpative surgery and aneurysm repair. However, it is unclear whether these data can be rightly extrapolated to predict lower extremity bypass (LEB) outcomes. Thus, the purpose of the present study was to examine whether the annualized case volume vs surgeon experience is more consequential in predicting for successful LEB reconstruction. METHODS: A total of 25,852 procedures with sufficient 1-year follow-up data from the Society for Vascular Surgery Vascular Quality Initiative infrainguinal bypass registry (2003-2019) were reviewed for chronic limb threatening ischemia among patients undergoing infrageniculate reconstruction. The procedures were categorized according to surgeon years of practice experience at surgery (ie, 0-5, 6-10, 11-15, >15 years) and the number of LEB procedures performed by the surgeon during the year of surgery (volume quartiles: 1-8, 9-14, 15-21, and >21). Mixed effects logistic and Cox regression models were used to assess the effects of experience, volume, and their interaction on outcomes. RESULTS: Increasing practice experience was more significantly associated with a reduction of in-hospital complications (odds ratio, 0.97; 95% confidence interval [CI], 0.96-0.99; P = .002) and the risk of major adverse limb events (odds ratio, 0.94; 95% CI, 0.92-0.97; P < .0001) compared with the volume. Increasing experience and volume were both associated with increased freedom from thrombosis (hazard ratio, 0.95; 95% CI, 0.93-0.98; P = .001). In contrast, neither experience nor volume had any significant association with early mortality. However, a higher volume was associated with diminished long-term survival (hazard ratio, 1.04; 95% CI, 1.0-1.1; P = .01). The most experienced surgeons (>15 years' experience) were significantly more likely to perform LEB for rest pain (P < .0001). No significant differences were found in the bypass rates among patients with tissue loss. The most experienced and highest volume surgeons were more likely to use an autogenous and/or composite conduit, in situ reconstruction, and/or pedal targets (P < .05). Similarly, more experienced and higher volume surgeons had less blood loss and shorter procedure times (P < .0001). Overall, the most experienced surgeons (>15 years' experience) were significantly more likely to have a higher volume with a diminished risk for all LEB outcomes. CONCLUSIONS: Surgeon experience appears to have the most important role in predicting for overall LEB performance with improved in-hospital outcomes and major adverse limb events. The more experienced surgeons performed more complex reconstructions with fewer complications. These findings have significant clinical and educational implications as our most experienced surgeons approach retirement. Mentorship strategies to facilitate ongoing technical development among less experienced surgeons are imperative to sustain optimal limb salvage outcomes and have significant ramifications regarding expectations for regulatory and credentialing paradigms.

Effects of dual antiplatelet therapy on graft patency after lower extremity bypass.

OBJECTIVE: Current guidelines recommend single-agent antiplatelet therapy for patients with symptomatic peripheral artery disease and consideration of dual antiplatelet therapy (DAPT) after surgical revascularization. The objective of this study was both to explore prescribing patterns of single antiplatelet therapy vs DAPT after lower extremity bypass surgery and to investigate the effects of antiplatelet therapy on bypass graft patency. METHODS: A retrospective analysis of prospectively collected nonemergent infrainguinal lower extremity bypass operations entered in the national Vascular Quality Initiative (2003-2018) with captured long-term follow-up was performed. Patients discharged on aspirin monotherapy or DAPT were identified. Linear regression investigated temporal trends in antiplatelet use. Multivariable Cox regression investigated predictors of primary, primary assisted, and secondary patency. RESULTS: Of the 13,020 patients investigated, 52.2% were discharged on aspirin monotherapy and 47.8% on DAPT. The proportion of patients discharged on DAPT increased from 10.6% in 2003 to 60.6% in 2018 (P < .001). The DAPT cohort was younger, had higher rates of medical (hypertension, diabetes, congestive heart failure, chronic obstructive pulmonary disease) and atherosclerotic (coronary artery disease, prior coronary artery bypass graft or percutaneous coronary intervention, prior lower extremity intervention) comorbidities, and had higher risk bypass procedures (more distal targets, prior inflow bypass procedure, prosthetic conduit use). Multivariable Cox regression analysis did not show any difference between the DAPT and aspirin cohorts in primary patency (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.88-1.10; P = .78), primary assisted patency (HR, 0.93; 95% CI, 0.80-1.07; P = .30), or secondary patency (HR, 0.88; 95% CI, 0.74-1.06; P = .18). On subgroup analysis based on bypass conduit, DAPT was found to have a protective effect on patency only in the prosthetic bypass cohort (primary patency: HR, 0.81 [95% CI, 0.66-1.00; P = .05]; primary assisted patency: HR, 0.74 [95% CI, 0.58-0.94; P = .01]; and secondary patency: HR, 0.60 [95% CI, 0.44-0.82; P < .001]). No patency differences were observed on adjusted subgroup analysis for the other bypass conduits. CONCLUSIONS: A significant and increasing proportion of patients are discharged on DAPT after lower extremity bypass revascularization. These patients represent a higher risk cohort with more medical comorbidities and higher risk bypass features. After controlling for these differences, DAPT therapy had no beneficial effect on overall bypass graft patency or major adverse limb events. However, on subgroup analysis, DAPT was associated with improved bypass graft patency in patients receiving prosthetic bypass conduits. Further study is warranted to investigate optimal duration of DAPT therapy and its possible bleeding complications in prosthetic bypass patients.