Statin therapy is associated with improved perioperative outcomes and long-term mortality following carotid revascularization in the Vascular Quality Initiative.

OBJECTIVE: Statin therapy is the standard of care for patients with carotid artery stenosis given its proven cardiovascular benefits. However, the impact of statin therapy on outcomes in patients undergoing carotid revascularization in the Vascular Quality Initiative has not yet been evaluated. Therefore, our aim was to investigate the association of statin therapy with outcomes following carotid endarterectomy (CEA), transfemoral carotid artery stenting (tfCAS), and transcarotid artery revascularization (TCAR). METHODS: We identified all patients who underwent CEA, tfCAS, or TCAR in the Vascular Quality Initiative registry from January 2016 to September 2021. To compare outcomes, we stratified patients by procedure type and created 1:1 propensity score-matched cohorts of patients who received no preoperative statin therapy (within 36 hours of procedure) versus those who received preoperative statin therapy. Propensity scores incorporated demographic characteristics, comorbidities, carotid symptom status, preoperative medications, and physician and hospital procedural experience. The primary outcome was a composite end point of in-hospital stroke and/or death. As a secondary analysis, we performed repeat propensity score-matching by postoperative statin use (prescribed at discharge) and assessed 5-year mortality. Relative risks (RR) and hazard ratios (HR) were calculated using log binomial regression and Cox regression, respectively. RESULTS: Among 97,835 CEA, 20,303 tfCAS, and 22,371 TCAR patients, 15%, 17%, and 10% of patients did not receive preoperative statin therapy, respectively. Compared with statin use, no statin use was associated with a higher risk of in-hospital stroke or death among 13,434 matched CEA patients (no statin, 1.7% vs statin, 1.4%; RR, 1.2; 95% confidence interval [CI], 1.02-1.5) and among 2707 matched tfCAS patients (4.8% vs 2.8%; RR, 1.7; 95% CI, 1.3-2.3). However, there was no difference for this outcome by statin use among 2089 matched TCAR patients (1.8% vs 1.6%; RR, 1.1; 95% CI, 0.7-1.8). At 5 years, no statin therapy at discharge was associated with higher 5-year mortality after CEA (15% vs 10%; HR, 1.8; 95% CI, 1.6-2) and tfCAS (18% vs 14%; HR, 1.5; 95% CI, 1.2-1.8), but there was no difference after TCAR (14% vs 11%; HR, 1.3; 95% CI, 0.9-1.8). CONCLUSIONS: Compared with statin use, no statin use was associated with a higher risk of in-hospital stroke or death and 5-year mortality among CEA and tfCAS patients. Although there was no significant difference in outcomes among TCAR patients, this may in part be due to lower statistical power in this cohort. Overall, statin therapy is essential in the short- and long-term management of patients undergoing carotid revascularization. Our findings not only support current Society for Vascular Surgery recommendations for statin therapy in patients undergoing carotid revascularization, but they also highlight an important opportunity for quality improvement.

Impact of Frailty on Clinical Outcomes after Carotid Artery Revascularization.

BACKGROUND: Frailty has been increasingly recognized as an important risk factor for vascular procedures. To assess the impact of frailty on clinical outcomes and resource utilization in patients undergoing carotid revascularization using a national cohort. METHODS: The 2005-2017 National Inpatient Sample was used to identify patients who underwent carotid endarterectomy (CEA) or carotid stenting (CAS). Patients were classified as frail using diagnosis codes defined by the Johns Hopkins Adjusted Clinical Groups frailty indicator. Multivariable regression was used to evaluate associations between frailty and in-hospital mortality, postoperative stroke, myocardial infarction (MI), hospitalization costs, and length of stay (LOS). RESULTS: Of 1,426,343 patients undergoing carotid revascularization, 59,158 (4.2%) were identified as frail. Among frail patients, 79.4% underwent CEA and 20.6% underwent CAS. Compared to CEA, a greater proportion of patients undergoing CAS were frail (6.0% vs. 3.8%, P < 0.001). Compared to the nonfrail cohort, frail patients had higher rates of mortality (2.2% vs. 0.5%, P < 0.001), postoperative stroke (2.6% vs. 1.0%, P < 0.001), MI (2.2% vs. 0.8%, P < 0.001), and stroke/death (4.4% vs. 1.4%, P < 0.001). After adjustment, frailty was associated with increased odds of mortality (AOR = 1.59, 95% CI: 1.30-1.80, P < 0.001), stroke (AOR = 1.66, 95% CI: 1.38-1.83 P < 0.001), MI (AOR = 1.51, 95% CI: 1.29-1.72, P < 0.001), and stroke/death (AOR = 1.62, 95% CI: 1.45-1.81, P < 0.001). Furthermore, frailty was associated with increased hospitalization costs (ß = +$5,980, 95% CI: $5,490-$6,470, P < 0.001) and LOS (ß = +2.6 days, 95% CI: 2.4-2.8, P < 0.001). CONCLUSIONS: Frailty is associated with adverse outcomes and greater resource use for those undergoing carotid revascularization. Risk models should include an assessment of frailty to guide management and improve outcomes for these high-risk patients.

Impact of Frailty on Clinical and Financial Outcomes Following Minor Lower Extremity Amputation: A Nationwide Analysis.

Frailty has been shown to portend worse outcomes in surgical patients. Our goal was to identify the impact of frailty on outcomes and resource utilization among patients undergoing minor lower extremity amputation in the United States. Using the Nationwide Readmission Database, we identified all adults undergoing a minor amputation between 2010 and 2015, and assessed 90-day outcomes, including readmission, reamputation, mortality, and cumulative hospitalization costs. Frailty was defined by International Classification of Diseases codes consistent with the ten frailty clusters as defined by the Johns Hopkins Adjusted Clinical Group System. Multivariable regression models were developed for risk adjustment. An estimated 302 798 patients (mean age = 61.8 years) were identified, of which 15.2% were categorized as Frail. Before adjustment, frailty was associated with increased rates of readmission (44% vs. 36%, P < .001) and in-hospital mortality (4% vs. 2%, P < .001). Frailty was also associated with increased cumulative costs of care ($39 417 vs. $27 244, P < .001). After risk adjustment, frailty remained an independent predictor of readmission (Adjusted odds ratio [AOR] 1.18, CI 1.14-1.23), in-hospital mortality (AOR 1.48, CI 1.34-1.65), and incremental costs (+$7 646, CI $6927-$8365). Frailty is an independent marker of worse outcomes following minor foot amputation, and may be utilized to direct quality improvement efforts.

Thirty-Day Outcomes After Open Revascularization for Acute Mesenteric Ischemia From the American College of Surgeons National Surgical Quality Improvement Program.

BACKGROUND: Open revascularization for acute mesenteric ischemia (AMI) is associated with high perioperative morbidity and mortality; however, results from contemporary studies are varied. Therefore, we evaluated 30-day mortality after open revascularization for AMI and identified preoperative factors associated with mortality. METHODS: We performed a retrospective cohort study of patients in the American College of Surgeons National Surgical Quality Improvement Program database undergoing open mesenteric revascularization for AMI from 2005 to 2017. The primary outcome was 30-day mortality. We used multivariable logistic regression to identify preoperative factors independently associated with 30-day mortality. RESULTS: The study cohort included 918 patients; their median age was 70 years (interquartile range: 59-80 years), 62% were female, and 90% were white. Thirty-day mortality after open revascularization for AMI was 32%, specifically 35% after embolectomy, 31% after thromboendarterectomy, and 28% after mesenteric bypass. Mortality was higher in patients requiring concomitant bowel resection (38% vs. 29%, respectively, P < 0.01). The preoperative factor most strongly associated with 30-day mortality was disseminated cancer (odds ratio = 8.8, 95% confidence interval = 2.4-32, P = 0.001). Other factors independently associated with mortality were renal dysfunction, preoperative intubation, preoperative blood transfusion, diabetes, elevated preoperative international normalized ratio, elevated preoperative white blood cell count, and increasing age. CONCLUSIONS: In this retrospective cohort study using a real-world, nationwide cohort, open revascularization for AMI was associated with high mortality, with nearly one-third of patients dying within 30 days of their operation. The factors identified to be independently associated with 30-day mortality, particularly disseminated cancer, preoperative renal dysfunction, and elevated preoperative WBC count, are an important tool for preoperative risk stratification.

Select type I and type III endoleaks at the completion of fenestrated endovascular aneurysm repair resolve spontaneously.

OBJECTIVE: The Society for Vascular Surgery reporting standards for endovascular aneurysm repair (EVAR) consider the presence of a type I or type III endoleak a technical failure. However, the nature and implications of these endoleaks in fenestrated EVAR (FEVAR) are not well understood. METHODS: We performed a single-center retrospective review of 53 patients who underwent FEVAR with the Zenith Fenestrated AAA Endovascular Graft (Cook Medical, Bloomington, Ind) from 2013 to 2018. We excluded one patient without contrast-enhanced postoperative imaging who was lost to follow-up after discharge. Small, slow, type I and type III endoleaks on completion angiography were routinely observed. We identified patients with completion type I or type III endoleaks by angiography review and characterized endoleak type, location, and rate of resolution on initial postoperative imaging. RESULTS: Fifty-two patients were included; mean age was 75 ± 8 years, 75% were male, and 91% were white. Of 146 visceral vessels (100 renal arteries and 46 superior mesenteric arteries), 145 (99%) were preserved with 103 fenestrations and 43 scallops; 102 (70%) target vessels were stented. After implantation of all device components, 31 patients (60%) had evidence of type I or type III endoleak. Twelve patients (39%) underwent further intervention at the index procedure, and three endoleaks resolved completely. Twenty-eight patients (54%) had a type I or type III endoleak on completion angiography. There were no differences between patients with and without completion endoleaks in baseline demographics, graft design, neck anatomy, or proportion of cases performed within the instructions for use of the device. Perioperative mortality was 1.9%. On initial postoperative imaging, 27 of 28 (96%) endoleaks resolved spontaneously. One small, persistent type IA or type III endoleak was identified on postoperative day 27 and was observed. This endoleak had resolved completely on computed tomography angiography 6 months postoperatively. In patients without a completion endoleak, one type IA endoleak secondary to graft infolding was discovered on postoperative imaging and was successfully treated with placement of endoanchors and Palmaz stent. Median follow-up was 269 days. No additional type I or type III endoleaks were identified in any patient for the duration of follow-up. CONCLUSIONS: Whereas completion type I and type III endoleaks are common after FEVAR with the ZFEN device, nearly all of these endoleaks resolve spontaneously by the initial postoperative imaging. These results suggest that select completion endoleaks after FEVAR with the ZFEN device do not require intervention at the index procedure.

Vascular fellow and resident experience performing infrapopliteal revascularization with endovascular procedures and vein bypass during training.

OBJECTIVE: Endovascular aneurysm repair has led to a significant reduction in vascular trainee experience in the surgical treatment of aortic aneurysms. We sought to evaluate whether the vascular training paradigm or the "endovascular first" approach to lower extremity vascular disease has had a similar effect on trainee experience with infrapopliteal endovascular therapy and vein bypass. METHODS: Deidentified data were provided by the Vascular Surgery Board on the number of procedures performed by each 2014 fellowship and residency (0 + 5) graduate during training. Data were analyzed using parametric and nonparametric methods, where appropriate. RESULTS: Of 125 trainees (109 fellows, 16 residents), 33 (27%) performed 10 or fewer infrapopliteal vein bypasses and 37 (29%) performed 10 or fewer infrapopliteal endovascular procedures during their training. Eleven trainees (9%) performed 10 or fewer of both procedures. There was a positive correlation between number of infrapopliteal vein bypass and endovascular procedures performed (r = 0.19; P = .03). There was no difference between fellows and residents in the mean number of bypass operations performed during training (17.3 vs 19.1; P = .50; range, 0-53). However, residents performed more infrapopliteal endovascular procedures than fellows did (median, 29 vs 16; P = .03; range, 0-128). CONCLUSIONS: More than one in four graduates of both training paradigms finish with a low number of infrapopliteal bypasses and endovascular interventions. The number of these procedures needed for proficiency is not known. Vascular surgery training programs should critically evaluate the number of infrapopliteal procedures required to achieve proficiency.

Regional variation in patient selection and treatment for carotid artery disease in the Vascular Quality Initiative.

OBJECTIVE: Previous studies involving large administrative data sets have revealed regional variation in the demographics of patients selected for carotid endarterectomy (CEA) and carotid artery stenting (CAS) but lacked clinical granularity. This study aimed to evaluate regional variation in patient selection and operative technique for carotid artery revascularization using a detailed clinical registry. METHODS: All patients who underwent CEA or CAS from 2009 to 2015 were identified in the Vascular Quality Initiative (VQI). Deidentified regional groups were used to evaluate variation in patient selection, operative technique, and perioperative management. χ2 analysis was used to identify significant variation across regions. RESULTS: A total of 57,555 carotid artery revascularization procedures were identified. Of these, 49,179 patients underwent CEA (asymptomatic: median, 56%; range, 46%-69%; P < .01) and 8376 patients underwent CAS (asymptomatic: median, 36%; range, 29%-51%; P < .01). There was significant regional variation in the proportion of asymptomatic patients being treated for carotid stenosis <70% in CEA (3%-9%; P < .01) vs CAS (3%-22%; P < .01). There was also significant variation in the rates of intervention for asymptomatic patients older than 80 years (CEA, 12%-27% [P < .01]; CAS, 8%-26% [P < .01]). Preoperative computed tomography angiography or magnetic resonance angiography in the CAS cohort also varied widely (31%-83%; P < .01), as did preoperative medical management with combined aspirin and statin (CEA, 53%-77% [P < .01]; CAS, 62%-80% [P < .01]). In the CEA group, the use of shunt (36%-83%; P < .01), protamine (32%-89%; P < .01), and patch (87%-99%; P < .01) varied widely. Similarly, there was regional variation in frequency of CAS done without a protection device (1%-8%; P < .01). CONCLUSIONS: Despite clinical benchmarks aimed at guiding management of carotid disease, wide variation in clinical practice exists, including the proportion of asymptomatic patients being treated by CAS and preoperative medical management. Additional intraoperative variables, including the use of a patch and protamine during CEA and use of a protection device during CAS, displayed similar variation in spite of clear guidelines. Quality improvement projects could be directed toward improved adherence to benchmarks in these areas.

Results for primary bypass versus primary angioplasty/stent for lower extremity chronic limb-threatening ischemia.

BACKGROUND: Long-term results comparing percutaneous transluminal angioplasty with or without stenting (PTA/S) and open surgical bypass for chronic limb-threatening ischemia (CLTI) in patients who have had no prior intervention are lacking. METHODS: All patients undergoing a first-time lower extremity revascularization for CLTI by vascular surgeons at our institution from 2005 to 2014 were retrospectively reviewed. Outcomes included perioperative complications, wound healing, restenosis, primary patency, reintervention, major amputation, RAS events (ie, reintervention, major amputation, or stenosis), and mortality. Outcomes were evaluated using χ2, Kaplan-Meier, and Cox regression analyses. RESULTS: Of the 2869 total lower extremity revascularizations performed between 2005 and 2014, there were 1336 that fit our criteria of a first-time lower extremity intervention for CLTI (668 bypass procedures and 668 PTA/S procedures). Bypass patients were younger (71 vs 72 years; P = .02) and more often male (62% vs 56%; P < .02). Total mean hospital length of stay (LOS) was significantly longer after a first-time bypass (10 vs 8 days; P < .001), as were mean preoperative LOS (4 vs 3 days; P < .01) and postoperative LOS (7 vs 5 days; P < .001). There was no difference in perioperative mortality (3% vs 3%; P = .63). Surgical site infection occurred in 10% of bypass patients. Freedom from reintervention was significantly higher in patients undergoing a first-time bypass procedure (62% vs 52% at 3 years; P = .04), as was freedom from restenosis (61% vs 45% at 3 years; P < .001). Complete wound healing at 6-month follow-up was significantly better after an initial bypass (43% vs 36%; P < .01). A Cox regression model of all patients showed that reintervention was predicted by a first-time PTA/S (hazard ratio, 1.6; 95% confidence interval, 1.3-2.1) and both preoperative femoropopliteal TransAtlantic Inter-Society Consensus (TASC) C and TASC D lesions (2.0 [1.3-3.1] and 1.8 [1.3-2.7], respectively). Major amputation among all patients was predicted by an initial presentation of gangrene (2.5 [1.3-5.0]), dialysis dependence (1.9 [1.3-2.9]), diabetes (2.0 [1.1-3.8]), and preoperative femoropopliteal TASC D lesions (2.1 [1.1-4.0]) and was not predicted by procedure type. CONCLUSIONS: In this retrospective analysis, bypass for the primary treatment of CLTI showed improved 6-month wound healing, higher freedom from restenosis, improved patency rates, significantly fewer reinterventions, and higher survival than PTA/S within 3 years; however, a bypass-first approach was associated with increased total hospital LOS and wound infection. Perioperative mortality and amputation rates were similar between procedure types.

Predictive ability of the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system after first-time lower extremity revascularizations.

OBJECTIVE: The Society for Vascular Surgery (SVS) Wound, Ischemia and foot Infection (WIfI) classification system was proposed to predict 1-year amputation risk and potential benefit from revascularization. Our goal was to evaluate the predictive ability of this scale in a real-world selection of patients undergoing a first-time lower extremity revascularization for chronic limb-threatening ischemia (CLTI). METHODS: From 2005 to 2014, 1336 limbs underwent a first-time lower extremity revascularization for CLTI, of which 992 had sufficient data to classify all three WIfI components (wound, ischemia, and foot infection). Limbs were stratified into the SVS WIfI clinical stages (from 1 to 4) for 1-year amputation risk estimation, a novel WIfI composite score from 0 to 9 (that weighs all WIfI variables equally), and a novel WIfI mean score from 0 to 3 (that can incorporate limbs missing any of the three WIfI components). Outcomes included major amputation; revascularization, major amputation, or stenosis (>3.5× step-up by duplex; RAS) events; and death. Predictors were identified using Cox regression models and Kaplan-Meier survival estimates. RESULTS: Of the 1336 first-time procedures performed, 992 limbs were classified in all three WIfI components (524 endovascular and 468 bypass; 26% rest pain and 74% tissue loss). Cox regression demonstrated that a one-unit increase in the WIfI clinical stage increases the risk of major amputation (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.7-3.2) and RAS events in all limbs (HR, 1.2; 95% CI, 1.1-1.3). Separate models of the entire cohort, a bypass-only cohort, and an endovascular-only cohort showed that a one-unit increase in the WIfI mean score is associated with an increase in the risk of major amputation (all three cohorts: HR, 5.3 [95% CI, 3.6-6.8], 4.1 [2.4-6.9], and 6.6 [3.8-11.6], respectively) and RAS events (all three cohorts: HR, 1.7 [95% CI, 1.4-2.0], 1.9 [1.4-2.6], and 1.4 [1.1-1.9], respectively). The novel WIfI composite and WIfI mean scores were the only consistent predictors of death among the three cohorts, with the WIfI mean score proving most strongly predictive in the entire cohort (HR, 1.4; 95% CI, 1.1-1.7), the bypass-only cohort (HR, 1.5; 95% CI, 1.1-1.9), and the endovascular-only cohort (HR, 1.4; 95% CI, 1.0-1.8). Although the individual WIfI wound component was able to predict mortality among all patients (HR, 1.1; 95% CI, 1.0-1.2) and bypass-only patients (HR, 1.2; 95% CI, 1.1-1.3), neither the additional individual WIfI components nor the WIfI clinical stage were able to significantly predict mortality among any cohort. CONCLUSIONS: This study supports the ability of the SVS WIfI classification system to predict major amputation; however, the novel WIfI mean and WIfI composite scores predict amputation, RAS events, and mortality more consistently than any other current WIfI scoring system. The WIfI mean score allows inclusion of all limbs, and both novel scoring systems are easier to conceptualize, give equal weight to each WIfI component, and may provide clinicians more effective comparisons in outcomes between patients.

The effect of surgeon and hospital volume on mortality after open and endovascular repair of abdominal aortic aneurysms.

BACKGROUND: Higher hospital and surgeon volumes are independently associated with improved mortality after open repair of abdominal aortic aneurysms (AAAs) in the era before endovascular AAA repair (EVAR). The effects of both surgeon and hospital volume on mortality after EVAR and open repair in the current era are less well defined. METHODS: We studied Medicare beneficiaries who underwent elective AAA repair from 2001 to 2008. Volume was measured by procedure type during the 1-year period preceding each procedure and was further categorized into quintiles of volume for surgeon and hospital. Multilevel logistic regression models were used to evaluate the effect of surgeon volume, accounting for hospital volume, on mortality after adjusting for patient demographic and comorbid conditions as well as the analogous effect of hospital volume adjusting for surgeon volume. The multilevel models included random effects for surgeon and hospital to account for the clustering of multiple patients within the same surgeon and within the same hospital. RESULTS: We studied 122,495 patients who underwent AAA repair (open: 45,451; EVAR: 77,044). After EVAR, perioperative mortality did not differ by surgeon volume (quintile 1 [0-6 EVARs]: 1.8%; quintile 5 [28-151 EVARs]: 1.6%; P = .29), but decreased with greater hospital volume (quintile 1 [0-9 EVARs]: 1.9%; quintile 5 [49-198 EVARs]: 1.4%; P < .01). After open repair, perioperative mortality decreased with both higher surgeon volume (quintile 1 [0-3 open repairs]: 6.4%; quintile 5 [14-62 open repairs]: 3.8%; P < .01) and hospital volume (quintile 1 [0-5 open repairs]: 6.3%; quintile 5 [14-62 open repairs]: 3.8%; P < .01). After adjustment for other predictors, surgeon volume was not associated with perioperative mortality after EVAR (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.7-1.1); however, hospital volume was associated with higher perioperative mortality (quintile 1: OR, 1.5; 95% CI, 1.2-1.9; quintile 2: OR, 1.3; 95% CI, 1.02-1.6; and quintile 3: OR, 1.2; 95% CI, 1.01-1.5, compared with 5). After open repair, higher surgeon volume was also associated with lower mortality (quintile 1: OR, 1.5; 95% CI, 1.3-1.8; quintile 2: OR, 1.3; 95% CI, 1.1-1.6; and quintile 3: OR, 1.2; 95% CI, 1.1-1.4, compared with 5). Risk of mortality also was higher for patients treated at lower-volume hospitals (quintile 1: OR, 1.3; 95% CI, 1.1-1.5; quintile 2: OR, 1.3; 95% CI, 1.1-1.5; and quintile 3: OR, 1.2; 95% CI, 1.1-1.4, compared with 5). CONCLUSIONS: After EVAR, hospital volume is minimally associated with perioperative mortality, with no such association for surgeon volume. After open AAA repair, surgeon and hospital volume are both strongly associated with mortality. These findings suggest that open surgery should be concentrated in hospitals and surgeons with high volume.

Patient selection and perioperative outcomes are similar between targeted and nontargeted hospitals (in the National Surgical Quality Improvement Program) for abdominal aortic aneurysm repair.

OBJECTIVE: The targeted vascular module in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) consists of self-selected hospitals that choose to collect extra clinical details for better risk adjustment and improved procedure-specific outcomes. The purpose of this study was to compare patient selection and outcomes between targeted and nontargeted hospitals in the NSQIP regarding the operative management of abdominal aortic aneurysm (AAA). METHODS: We identified all patients who underwent endovascular aneurysm repair (EVAR) or open AAA repair from 2011 to 2013 and compared cases by whether the operation took place in a targeted or nontargeted hospital. EVAR and open repair as well as intact and ruptured aneurysms were evaluated separately. Only variables contained in both modules were used to evaluate rupture status and operation type. All thoracoabdominal aneurysms were excluded. Univariate analysis was performed for intact and ruptured EVAR and open repair grouped by complexity, defined as visceral involvement in open repair and a compilation of concomitant procedures for EVAR. Multivariable models were developed to identify effect of hospital type on mortality. RESULTS: There were 17,651 AAA repairs identified. After exclusion of aneurysms involving the thoracic aorta (n = 352), there were 1600 open AAA repairs at targeted hospitals (21% ruptured) and 2725 at nontargeted hospitals (19% ruptured) and 4986 EVARs performed at targeted hospitals (6.7% ruptured) and 7988 at nontargeted hospitals (5.2% ruptured). There was no significant difference in 30-day mortality rates between targeted and nontargeted hospitals for intact aneurysms (EVAR noncomplex, 1.8% vs 1.4% [P = .07]; open repair noncomplex, 4.2% vs 4.5% [P = .7]; EVAR complex, 5.0% vs 3.2% [P = .3]; open repair complex, 8.0% vs 6.0% [P = .2]). For ruptured aneurysms, again there was no difference in mortality between the targeted and nontargeted hospitals (EVAR noncomplex, 23% vs 25% [P = .4]; open repair noncomplex, 38% vs 34% [P = .2]; EVAR complex, 29% vs 33% [P = 1.0]; open repair complex, 27% vs 41% [P = .09]). Multivariable analysis further demonstrated that having an operation at a targeted vs nontargeted hospital had no impact on mortality for both intact and ruptured aneurysms (odds ratio, 1.1 [0.9-1.4] and 1.0 [0.8-1.3], respectively). CONCLUSIONS: This analysis highlights the similarities between targeted and nontargeted hospitals within the NSQIP for AAA operative management and suggests that data from the targeted NSQIP, in terms of AAA management, are generalizable to all NSQIP hospitals.

Multicenter Experience of Surgical Explantation of Carotid Stents for Recurrent Stenosis.

OBJECTIVE: A significant cohort of patients who have undergone carotid artery stenting (CAS) will have in-stent restenosis (ISR). The optimal management of symptomatic or severe ISR remains poorly defined. The purpose of this study was to describe the indications, treatment, and mid- to long-term outcomes of patients undergoing CAS explantation for ISR. METHODS: All patients undergoing internal carotid artery stent explantation with carotid artery reconstruction at Mayo Clinic Rochester, Dartmouth-Hitchcock Medical Center, and Beth-Israel Deaconess Medical Center from 2003 to 2013 were retrospectively reviewed. Isolated common carotid artery stents were excluded. Demographics, comorbidities, indications for explantation, operative details, and perioperative and postoperative outcomes were reviewed. RESULTS: Over the study interval, a total of 971 patients underwent carotid stenting across the 3 centers. Of these, 8 patients ultimately underwent CAS explantation with carotid artery reconstruction. Mean age was 69 years and 5 patients were male. Index stent placement was for symptomatic stenosis in 4 patients, asymptomatic restenosis after endarterectomy in 2 patients, asymptomatic high lesion in 1 patient, and asymptomatic critical stenosis in 1 patient. Indications for explantation were symptomatic ISR in 4 patients and asymptomatic severe ISR in 4 patients. Method of repair was stent explantation and patch angioplasty in 5 and en bloc carotid resection with bypass in 3 patients. There were no perioperative neurologic events or cranial nerve injuries. At a mean follow-up of 38.7 months, there were 2 late disabling ipsilateral strokes (14.4 months and 19.1 months). CONCLUSION: A significant cohort of patients who have undergone CAS will have ISR. Although excellent perioperative results after surgical explantation can be obtained, this patient subgroup remains at risk for late neurologic events. Appropriate patient selection and diligent long-term follow-up are mandated to obtain optimal outcomes.

Clinical results of single-vessel versus multiple-vessel infrapopliteal intervention.

OBJECTIVE: The effects of concomitant endovascular interventions on multiple infrapopliteal vessels are not well known, and the short-term and long-term sequelae of such procedures have not been reported. METHODS: From 2004 to 2014, 673 limbs in 528 patients underwent an infrapopliteal endovascular intervention for tissue loss (77%), rest pain (13%), stenosis of a previously treated vessel (5%), acute limb ischemia (3%), or claudication (2%). Outcomes included wound healing, RAS events (reintervention, major amputation, or stenosis [>3.5x step-up by duplex]), and mortality. Patients without an initial indication of critical limb ischemia (CLI) were excluded. Patients were characterized as having undergone either a single-vessel infrapopliteal intervention or a multiple-vessel infrapopliteal intervention. RESULTS: Of the 673 limbs, 558 underwent a successful infrapopliteal endovascular intervention for CLI (86% for tissue loss, 14% for rest pain). During a single procedure, 503 limbs (90%) underwent a single-vessel intervention and 55 (10%) underwent a multiple-vessel intervention. Patients undergoing a single-vessel intervention more commonly underwent a prior ipsilateral endovascular procedure (17% vs 6%; P = .03) or a prior ipsilateral bypass procedure (20% vs 9%; P = .04). Kaplan-Meier analysis revealed that a RAS event ≤1 year occurred in 229 limbs (49%), with no significant difference in the 1-year rates of reintervention (22% vs 20%; P = .53), major amputation (16% vs 10%; P = .24), or stenosis (29% vs 21%; P = .25). After adjustment for baseline characteristics, multivariable regression illustrated that neither major amputation rates nor RAS events differed between patients undergoing a single-vessel vs a multiple-vessel intervention (P = .26 and P = .61, respectively). CONCLUSIONS: Our data suggest that a multiple-vessel intervention does not improve outcomes when compared to a single-vessel intervention following infrapopliteal angioplasty for CLI.

Predictive ability of the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system following infrapopliteal endovascular interventions for critical limb ischemia.

OBJECTIVE: The Society for Vascular Surgery (SVS) Lower Extremity Guidelines Committee has composed a new threatened lower extremity classification system that reflects the three major factors that impact amputation risk and clinical management: Wound, Ischemia, and foot Infection (WIfI). Our goal was to evaluate the predictive ability of this scale following any infrapopliteal endovascular intervention for critical limb ischemia (CLI). METHODS: From 2004 to 2014, a single institution, retrospective chart review was performed at the Beth Israel Deaconess Medical Center for all patients undergoing an infrapopliteal angioplasty for CLI. Throughout these years, 673 limbs underwent an infrapopliteal endovascular intervention for tissue loss (77%), rest pain (13%), stenosis of a previously treated vessel (5%), acute limb ischemia (3%), or claudication (2%). Limbs missing a grade in any WIfI component were excluded. Limbs were stratified into clinical stages 1 to 4 based on the SVS WIfI classification for 1-year amputation risk, as well as a novel WIfI composite score from 0 to 9. Outcomes included patient functional capacity, living status, wound healing, major amputation, major adverse limb events, reintervention, major amputation, or stenosis (RAS) events (> ×3.5 step-up by duplex), amputation-free survival, and mortality. Predictors were identified using Kaplan-Meier survival estimates and Cox regression models. RESULTS: Of the 596 limbs with CLI, 551 were classified in all three WIfI domains on a scale of 0 (least severe) to 3 (most severe). Of these 551, 84% were treated for tissue loss and 16% for rest pain. A Cox regression model illustrated that an increase in clinical stage increases the rate of major amputation (hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.1-2.3). Separate regression models showed that a one-unit increase in the WIfI composite score is associated with a decrease in wound healing (HR, 1.2; 95% CI, 1.1-1.4) and an increase in the rate of RAS events (HR, 1.2; 95% CI, 1.1-1.4) and major amputations (HR, 1.4; 95% CI, 1.2-1.8). CONCLUSIONS: This study supports the ability of the SVS WIfI classification system to predict 1-year amputation, RAS events, and wound healing in patients with CLI undergoing endovascular infrapopliteal revascularization procedures.

The perioperative effect of concomitant procedures during open infrarenal abdominal aortic aneurysm repair.

BACKGROUND: Open repair of abdominal aortic aneurysms (AAAs) is occasionally performed in conjunction with additional procedures; however, how these concomitant procedures affect outcome is unclear. This study determined the frequency of additional procedures during elective open AAA repair and the effect on perioperative outcomes. METHODS: All elective infrarenal open AAA repairs between January 2003 and November 2014 in the Vascular Study Group of New England (VSGNE) were identified. Patients were grouped by concomitant procedures, which included no concomitant procedure, renal artery bypass, lower extremity bypass, other abdominal procedure, or thromboembolectomy. Analyses were performed using multivariable logistic regression. RESULTS: Of 1314 patients who underwent elective AAA repair, 153 (11.6%) had a concomitant procedure, including renal bypass in 27 (2.1%), lower extremity bypass in 28 (2.1%), other abdominal procedures in 64 (4.9%), and thromboembolectomy in 48 (3.7%). Independent risk factors for 30-day mortality were renal bypass (odds ratio [OR], 7.2; 95% confidence interval [CI], 1.9-27.7), other abdominal procedures (OR, 4.8; 95% CI, 1.6-14.1), and thromboembolectomy (OR, 8.8; 95% CI, 3.1-24.9). Deterioration of renal function was predicted by renal bypass (OR, 5.1; 95% CI, 2.1-12.4) and thromboembolectomy (OR, 3.7; 95% CI, 1.8-7.6). Lower extremity bypass and thromboembolectomy were predictive of postoperative leg ischemia (OR, 8.9; 95% CI, 2.7-29.0; OR, 11.2; 95% CI, 4.4-28.8, respectively), and thromboembolectomy was also predictive of postoperative bowel ischemia (OR, 4.4; 95% CI, 1.6-12.0). CONCLUSIONS: Performing additional procedures during infrarenal open AAA repair is associated with increased morbidity and mortality in the postoperative period. Careful deliberation of the operative risks and the necessity of the additional interventions are therefore advised during operative planning. This study also highlights the importance of avoiding perioperative thromboembolic events.

Management and outcomes of isolated renal artery aneurysms in the endovascular era.

OBJECTIVE: Isolated renal artery aneurysms are rare, and controversy remains about indications for surgical repair. Little is known about the impact of endovascular therapy on selection of patients and outcomes of renal artery aneurysms. METHODS: We identified all patients undergoing open or endovascular repair of isolated renal artery aneurysms in the Nationwide Inpatient Sample from 1988 to 2011 for epidemiologic analysis. Elective cases were selected from the period 2000 to 2011 to create comparable cohorts for outcome comparison. We identified all patients with a primary diagnosis of renal artery aneurysms undergoing open surgery (reconstruction or nephrectomy) or endovascular repair (coil or stent). Patients with concomitant aortic aneurysms or dissections were excluded. We evaluated patient characteristics, management, and in-hospital outcomes for open and endovascular repair, and we examined changes in management and outcomes over time. RESULTS: We identified 6234 renal artery aneurysm repairs between 1988 and 2011. Total repairs increased after the introduction of endovascular repair (8.4 in 1988 to 13.8 in 2011 per 10 million U.S. population; P = .03). Endovascular repair increased from 0 in 1988 to 6.4 in 2011 per 10 million U.S. population (P < .0001). However, there was no concomitant decrease in open surgery (5.5 in 1988 to 7.4 in 2011 per 10 million U.S. population; P = .28). From 2000 to 2011, there were 1627 open and 1082 endovascular elective repairs. Patients undergoing endovascular repair were more likely to have a history of coronary artery disease (18% vs 11%; P < .001), prior myocardial infarction (5.2% vs 1.8%; P < .001), and renal failure (7.7% vs 3.3%; P < .001). In-hospital mortality was 1.8% for endovascular repair, 0.9% for open reconstruction (P = .037), and 5.4% for nephrectomy (P < .001 compared with all revascularization). Complication rates were 12.4% for open repair vs 10.5% for endovascular repair (P = .134), including more cardiac (2.2% vs 0.6%; P = .001) and peripheral vascular complications (0.6% vs 0.0%; P = .014) with open repair. Open repair had a longer length of stay (6.0 vs 4.6 days; P < .001). After adjustment for other predictors of mortality, including age (odds ratio [OR], 1.05 per decade; 95% confidence interval [CI], 1.0-1.1; P = .001), heart failure (OR, 7.0; 95% CI, 3.1-16.0; P < .001), and dysrhythmia (OR, 5.9; 95% CI, 2.0-16.8; P = .005), endovascular repair was still not protective (OR, 1.6; 95% CI, 0.8-3.2; P = .145). CONCLUSIONS: More renal artery aneurysms are being treated with the advent of endovascular techniques, without a reduction in operative mortality or a reduction in open surgery. Indications for repair of renal artery aneurysms should be re-evaluated.

Open surgical revision provides a more durable repair than endovascular treatment for unfavorable vein graft lesions.

OBJECTIVE: Lower extremity bypass grafts that develop stenoses are commonly treated with either open surgical or endovascular revision. Vein graft stenoses with unfavorable lesions (multiple lesions, lesions >2 cm in length, lesions in grafts <3 months old, lesions in grafts <3 mm in diameter) fare worse than those with favorable lesions when treated with endovascular therapy. However, it is not known if unfavorable lesions fare better with surgical revision than with endovascular treatment or than favorable lesions treated with surgery. METHODS: We performed a retrospective review of 175 vein graft revisions performed at a single institution from 2000 to 2010. Characteristics of lesions treated with surgical and endovascular revision were identified. Cox proportional hazard models were used to identify predictors of revision failure (restenosis >75%, revision, or amputation). RESULTS: Ninety-one failing vein grafts (52%) were treated with surgical revision and 84 with endovascular treatment (48%), with a median follow-up of 30 months. Favorable lesions fared better than unfavorable lesions after endovascular treatment, with 12-month freedom from failure of 59% vs 34% (P < .01), but not after surgical revision (66% vs 62%; P = .90). Unfavorable lesions had better freedom from failure after surgery than endovascular treatment (62% vs 34%; P < .01), and results in favorable lesions were similar (66% vs 59%; P = .57). CONCLUSIONS: For the treatment of failing vein grafts, endovascular therapy appears adequate for favorable lesions and surgical revision is more durable for unfavorable lesions.

Long-Term Outcomes of Abdominal Aortic Aneurysm in the Medicare Population.

BACKGROUND: Randomized trials and observational studies have shown that perioperative morbidity and mortality are lower with endovascular repair of abdominal aortic aneurysm than with open repair, but the survival benefit is not sustained. In addition, concerns have been raised about the long-term risk of aneurysm rupture or the need for reintervention after endovascular repair. METHODS: We assessed perioperative and long-term survival, reinterventions, and complications after endovascular repair as compared with open repair of abdominal aortic aneurysm in propensity-score-matched cohorts of Medicare beneficiaries who underwent repair during the period from 2001 through 2008 and were followed through 2009. RESULTS: We identified 39,966 matched pairs of patients who had undergone either open repair or endovascular repair. The overall perioperative mortality was 1.6% with endovascular repair versus 5.2% with open repair (P<0.001). From 2001 through 2008, perioperative mortality decreased by 0.8 percentage points among patients who underwent endovascular repair (P=0.001) and by 0.6 percentage points among patients who underwent open repair (P=0.01). The rate of conversion from endovascular to open repair decreased from 2.2% in 2001 to 0.3% in 2008 (P<0.001). The rate of survival was significantly higher after endovascular repair than after open repair through the first 3 years of follow-up, after which time the rates of survival were similar. Through 8 years of follow-up, interventions related to the management of the aneurysm or its complications were more common after endovascular repair, whereas interventions for complications related to laparotomy were more common after open repair. Aneurysm rupture occurred in 5.4% of patients after endovascular repair versus 1.4% of patients after open repair through 8 years of follow-up (P<0.001). The rate of total reinterventions at 2 years after endovascular repair decreased over time (from 10.4% among patients who underwent procedures in 2001 to 9.1% among patients who underwent procedures in 2007). CONCLUSIONS: Endovascular repair, as compared with open repair, of abdominal aortic aneurysm was associated with a substantial early survival advantage that gradually decreased over time. The rate of late rupture was significantly higher after endovascular repair than after open repair. The outcomes of endovascular repair have been improving over time. (Funded by the National Institutes of Health.).

The effect of endovascular treatment on isolated iliac artery aneurysm treatment and mortality.

OBJECTIVE: Isolated iliac artery aneurysms are rare, but potentially fatal. The effect of recent trends in the use of endovascular iliac aneurysm repair (EVIR) on isolated iliac artery aneurysm-associated mortality is unknown. METHODS: We identified all patients with a primary diagnosis of iliac artery aneurysm in the National Inpatient Sample from 1988 to 2011. We examined trends in management (open vs EVIR, elective and urgent) and overall isolated iliac artery aneurysm-related deaths (with or without repair). We compared in-hospital mortality and complications for the subgroup of patients undergoing elective open and EVIR from 2000 to 2011. RESULTS: We identified 33,161 patients undergoing isolated iliac artery aneurysm repair from 1988 to 2011, of which there were 9016 EVIR and 4933 open elective repairs from 2000 to 2011. Total repairs increased after the introduction of EVIR, from 28 to 71 per 10 million United States (U.S.) population (P < .001). EVIR surpassed open repair in 2003. Total isolated iliac artery aneurysm-related deaths, due to rupture or elective repair, decreased after the introduction of EVIR from 4.4 to 2.3 per 10 million U.S. population (P < .001). However, urgent admissions did not decrease during this time period (15 to 15 procedures per 10 million U.S. population; P = .30). Among elective repairs after 2000, EVIR patients were older (72.4 vs 69.4 years; P = .002) and were more likely to have a history of prior myocardial infarction (14.0% vs 11.3%; P < .001) and renal failure (7.2% vs 3.6%; P < .001). Open repair had significantly higher rate of in-hospital mortality (1.8% vs 0.5%; P < .001) and complications (17.9% vs 6.7%; P < .001) and a longer length of stay (6.7 vs 2.3 days; P < .001). CONCLUSIONS: Treatment of isolated iliac artery aneurysms has increased since the introduction of EVIR and is associated with lower perioperative mortality, despite a higher burden of comorbid illness. Decreasing iliac artery aneurysm-attributable in-hospital deaths are likely related primarily to lower elective mortality with EVIR rather than rupture prevention.

Risk factors and indications for readmission after lower extremity amputation in the American College of Surgeons National Surgical Quality Improvement Program.

BACKGROUND: Postoperative readmission, recently identified as a marker of hospital quality in the Affordable Care Act, is associated with increased morbidity, mortality, and health care costs, yet data on readmission after lower extremity amputation (LEA) are limited. We evaluated risk factors for readmission and postdischarge adverse events after LEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). METHODS: All patients undergoing transmetatarsal (TMA), below-knee (BKA), or above-knee amputation (AKA) in the 2011-2012 NSQIP were identified. Independent predischarge predictors of 30-day readmission were determined by multivariable logistic regression. Readmission indication and reinterventions, available in the 2012 NSQIP only, were also evaluated. RESULTS: We identified 5732 patients undergoing amputation (TMA, 12%; BKA, 51%; AKA, 37%). Readmission rate was 18%. Postdischarge mortality rate was 5% (TMA, 2%; BKA, 3%; AKA, 8%; P < .001). Overall complication rate was 43% (in-hospital, 32%; postdischarge, 11%). Reoperation was for wound-related complication or additional amputation in 79% of cases. Independent predictors of readmission included chronic nursing home residence (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.0-1.7), nonelective surgery (OR, 1.4; 95% CI, 1.1-1.7), prior revascularization/amputation (OR, 1.4; 95% CI, 1.1-1.7), preoperative congestive heart failure (OR, 1.7; 95% CI, 1.2-2.4), and preoperative dialysis (OR, 1.5; 95% CI, 1.2-1.9). Guillotine amputation (OR, 0.6; 95% CI, 0.4-0.9) and non-home discharge (OR, 0.7; 95% CI, 0.6-1.0) were protective of readmission. Wound-related complications accounted for 49% of readmissions. CONCLUSIONS: Postdischarge morbidity, mortality, and readmission are common after LEA. Closer follow-up of high-risk patients, optimization of medical comorbidities, and aggressive management of wound infection may play a role in decreasing readmission and postdischarge adverse events.