Clinical Impact of an Enhanced Recovery Program for Lower-extremity Bypass.

OBJECTIVE: To determine the association of Enhanced Recovery Program (ERP) implementation with length of stay (LOS) and perioperative outcomes after lower-extremity bypass (LEB). BACKGROUND: ERPs have been shown to decrease hospital LOS and improve perioperative outcomes, but their impact on patients undergoing vascular surgery remains unknown. METHODS: Patients undergoing LEB who received or did not receive care under the ERP were included; pre-ERP (January 1, 2016-May 13, 2018) and ERP (May 14, 2018-July 31, 2022). Clinicopathologic characteristics and perioperative outcomes were analyzed. RESULTS: Of 393 patients who underwent LEB [pre-ERP: n = 161 (41%); ERP: n = 232 (59%)], most were males (n = 254, 64.6%), White (n = 236, 60%), and government-insured (n = 265, 67.4%). Pre-ERP patients had higher Body Mass Index (28.8 ± 6.0 vs 27.4 ± 5.7, P = 0.03) and rates of diabetes (52% vs 36%, P = 0.002). ERP patients had a shorter total [6 (3-13) vs 7 (5-14) days, P = 0.01) and postoperative LOS [5 (3-8) vs 6 (4-8) days, P < 0.001]. Stratified by indication, postoperative LOS was shorter in ERP patients with claudication (3 vs 5 days, P = 0.01), rest pain (5 vs 6 days, P = 0.02), and tissue loss (6 vs 7 days, P = 0.03). ERP patients with rest pain also had a shorter total LOS (6 vs 7 days, P = 0.04) and lower 30-day readmission rates (32%-17%, P = 0.02). After ERP implementation, the average daily oral morphine equivalents decreased [median (interquartile range): 52.5 (26.6-105.0) vs 44.12 (22.2-74.4), P = 0.019], while the rates of direct discharge to home increased (83% vs 69%, P = 0.002). CONCLUSIONS: This is the largest single-center cohort study evaluating ERP in LEB, showing that ERP implementation is associated with shorter LOS and improved perioperative outcomes.

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.

Clinical practice and volume trends of inferior vena cava filter usage at a single tertiary care center during a 19-year period.

BACKGROUND: We investigated the clinical practice and volume trends of inferior vena cava filter (IVCF) usage at a single institution for an extended period and identified the potential factors affecting the clinical decision for placement, follow-up, and retrieval. METHODS: An institutional database was queried for IVCFs placed from 2000 to 2018 using the Current Procedural Terminology codes. The medical records were reviewed to evaluate the demographics, economic status, placement indication, IVCF type, follow-up evaluation for retrieval, and retrieval success rates. Statistical analysis was performed using SPSS, and t tests for continuous and χ2 for categorical variables. RESULTS: A total of 3915 IVCFs were placed from 2000 to 2018. The placement of IVCFs had increased steadily from 2000 (127 IVCFs/y), peaking in 2010 at 371 IVCFs/y and representing a 292% increase in IVCF usage. Since 2010, the number of IVCFs placed has steadily declined until 2016 to 2018, with a 426% decrease from the peak. In a subgroup of IVCFs placed for prophylaxis, the total volume trends paralleled a shift in clinical indications, peaking in 2010 and accounting for 45% of all IVCFs placed and then decreasing from 2013 to 2018 to ≤10%. Overall, 989 permanent IVCFs (25.3%) and 2926 retrievable IVCFs (74.7%) were placed during the entire study period. Before dedicated efforts to implement retrieval follow-up visits, the successful retrieval rate was ∼1% from 2000 to 2006 and had increased to ∼10% to 15% from 2007 to 2015, 36.7% in 2016, 40.2% in 2017, and 40.3% in 2018 after implementation of more active retrieval follow-up protocols. The predictors for the lack of evaluation for IVCF retrieval included an extended length of stay (P = .004) and geographic distance (P < .001). CONCLUSIONS: The use of IVCFs during the past 19 years at our institution reflected increased usage from 2000 to 2010, corresponding to an increase in prophylactic placement, followed by a decreasing total volume from 2011 to 2018, largely attributable to decreased prophylactic IVCF placement. Improved retrieval rates were seen after implementation of an active IVCF retrieval program.

Long-Term Trends in Preoperative Cardiac Evaluation and Myocardial Infarction after Elective Vascular Procedures.

BACKGROUND: Vascular surgery has seen rapid increase in the use of less invasive endovascular therapies along with advancements in cardiac perioperative optimization in the past 2 decades. However, a recent American College of Surgeons National Surgical Quality Improvement Program database study found no improvement in postoperative myocardial infarction (POMI) over a 10-year period in high-risk procedures. The national Society for Vascular Surgery Vascular Quality Initiative (VQI) registry provides a more in-depth characterization of vascular surgery procedures. Here, we sought to evaluate long-term trends in POMI using VQI registry data for patients undergoing carotid endarterectomy (CEA), thoracic endovascular aortic repair (TEVAR), endovascular aortic repair (EVAR), open abdominal aortic aneurysm repair (oAAA), suprainguinal bypass (SIB), and infrainguinal bypass (IIB). METHODS: A retrospective cohort study was performed using data on elective procedures from 2003 to 2017. Procedures were subdivided by date of operation into 3-year era consecutive groups for subanalysis (2003-05, 2006-08, 2009-11, 2012-14, and 2015-17). The incidence of POMI, preoperative risk factors (including individual patient VQI cardiac risk index (CRI)), and demographics were determined over time. RESULTS: A total of 227,837 elective procedures were identified: CEA (n = 88,805, 39.0%), TEVAR (n = 7,494, 3.3%), EVAR (n = 34,376, 15.1%), oAAA (n = 7,568, 3.3%), SIB (n = 11,354, 5.0%), and IIB (n = 34,661, 15.2%). Across all procedures, the overall rate of POMI was 1.3%. POMI rates from 2003-05 to 2015-17 for CEA decreased from 0.9% to 0.7% (P = 0.21), EVAR from 2.0% to 0.7%, P = 0.003, oAAA from 6.8% to 5.1% (P = 0.12), and IIB from 3.8% to 2.4% (P = 0.003). SIB POMI decreased from 3.06% to 2.95%, P = 0.85 from 2009 to 17. While POMI after TEVAR increased from 2.40% to 2.56% from 2009 to 17, P = 0.91. Over these same time periods, only EVAR and IIB had a reduction in CRIs (P = 0.059 and P < 0.001, respectively). CEA, EVAR, IIB, and oAAA all showed a significant (P < 0.001) increase in preoperative statin use. CONCLUSIONS: Except for TEVAR, the incidence of POMI has remained unchanged or decreased over the past 15 years in VQI registries. Patients undergoing IIB and EVAR demonstrated decreases in POMI rates that correspond with a reduction in CRIs and increased preoperative statin use. CEA and SIB had no significant change in POMI rates nor CRIs. The etiology of decreased POMI rate is uncertain, but increasing statin use, patient-specific factors, and patient selection for procedures may be important drivers of this improvement.

Prevalence and Outcomes of Endovascular Infrapopliteal Interventions for Intermittent Claudication.

BACKGROUND: Although endovascular peripheral vascular interventions (PVI) are typically limited to vessels above the knee in intermittent claudication (IC), some patients have concomitant or isolated infrapopliteal disease with IC. The benefits and risks of undergoing tibial intervention remain unclear in IC patients. The purpose of this study is to evaluate the prevalence and outcomes of infrapopliteal PVI for IC. METHODS: The Vascular Quality Initiative was queried for PVI procedures performed for IC between 2003 and 2018. Patients were divided into 3 groups: isolated femoropopliteal (FP), isolated infrapopliteal (IP), and combined above and below knee interventions (COM). Multivariable logistic regression models identified predictors of minor and major amputation, as well as freedom from reintervention. Kaplan-Meier plots estimate amputation-free survival. RESULTS: We identified 34,944 PVI procedures for IC. There were 31,110 (89.0%) FP interventions, 1,045 (3.0%) IP interventions, and 2,789 (8.0%) COM interventions. Kaplan-Meier plots of amputation-free survival revealed that patients with any IP intervention had significantly higher rates of both minor and major amputation (log rank <0.001). Freedom from reintervention at 1-year was 89.2% for the FP group, 91.3% for the IP group, and 85.3% for the COM group (P < 0.0001). In multivariable analysis, factors associated with an increased risk of major amputation included isolated IP intervention (OR 6.47, 95% CI, 6.45-6.49; P < 0.0001), COM interventions (OR 2.32, 95% CI, 2.31-2.33; P < 0.0001), dialysis dependence (OR 3.34, 95% CI, 3.33-3.35; P < 0.0001), CHF (OR 1.86, 95% CI, 1.85-1.86; P = 0.021) and, nonwhite race (OR 1.64, 95% CI, 1.63-1.64; P = 0.013). CONCLUSIONS: PVI in the infrapopliteal vessels for IC is associated with higher amputation rates. This observation may suggest the need for more careful patient selection when performing PVI in patients with IC where disease extends into the infrapopliteal level.

Association between thoracoabdominal aneurysm extent and mortality after complex endovascular repair.

OBJECTIVE: Traditional open surgical repair of thoracoabdominal aortic aneurysms (TAAAs) has historically resulted in 30-day mortality rates ranging from 6% to 20%, depending on the Crawford anatomic extent. Although short-term survival is important, long-term survival is essential for patients to benefit from these often elective and potentially morbid procedures. The aneurysm extent affects the long-term survival after open repair; however, effect on endovascular repair is unknown and could influence the decision process for repair. We evaluated the association between aneurysm extent and survival and identified patient and perioperative factors associated with mortality after endovascular repair. METHODS: A retrospective cohort of patients treated for TAAAs recorded in the Society for Vascular Surgery Vascular Quality Initiative thoracic and complex endovascular aneurysm repair registry were evaluated. All patients treated for asymptomatic degenerative aneurysms from 2010 to 2019 were included. Crawford extent I to V was defined according to the proximal and distal landing zones documented in the registry. Patients without extension into the visceral aorta were used for comparison and categorized as having extent 0a or 0b, depending on the distal landing zone in the thoracic aorta. Kaplan-Meier plots were used to estimate survival, and Cox proportional hazard regression models were created to identify the predictors of mortality. RESULTS: From 2010 to 2019, 15,333 patients were entered into the registry, of whom 2062 met the inclusion criteria. The Crawford extent was 0a for 379, 0b for 848, I for 81, II for 98, III for 130, IV for 454, and V for 72. Three groups were created in accordance with the similar outcomes noted on a preliminary analysis: (1) extent 0a and 0b; (2) extent I, II, and III; and (3) extent IV and V. The mean survival time for the extent 0a and 0b group was 70.7 ± 1.43 months and was 48.6 ± 1.65 months for the extent I, II, and III group and 57.6 ± 1.24 months for the extent IV and V group. The corresponding 1-year mortality was 8.4%, 18.4%, and 7.8%. Cox regression analysis identified the following preoperative factors were associated with mortality: chronic obstructive pulmonary disease (odds ratio [OR], 1.70; P < .001), Crawford extent I to III (OR, 1.64; P = .015), preexisting chronic kidney disease (OR, 1.37; P = .024), and age per year (OR, 1.03; P < .001). A number of postoperative factors were also associated with mortality. CONCLUSIONS: Similar to open TAAA repair, patients with more extensive aortic disease treated with endovascular repair had worse 1-year and long-term survival. The extent of aortic disease and anticipated postoperative survival should factor prominently into the surgical decision-making process for elective endovascular TAAA repair.

Carotid endarterectomy with concomitant distal endovascular intervention is associated with increased rates of stroke and death.

OBJECTIVE: Carotid endarterectomy (CEA) with concomitant distal endovascular intervention (CEA+D) is infrequently necessary but has often been used as a salvage maneuver when complications occur during CEA. The present study aimed to determine whether preoperative risk factors associated with CEA requiring CEA+D exist and to evaluate the outcomes compared with isolated CEA. METHODS: The Vascular Quality Initiative CEA registry was used to identify patients who had undergone CEA or CEA+D for asymptomatic or symptomatic carotid stenosis from 2013 to 2019. Data regarding distal intervention included whether angioplasty or stenting of the distal internal carotid artery (ICA) and/or bifurcation had been required. However, information regarding the indication or whether the intervention had been planned was not included. The χ2 test and analysis of variance were used to evaluate the categorical and continuous perioperative variables. Variables with P < .20 on univariate analysis were included in the multivariable analysis to assess for preoperative predictors of the need for CEA+D and the association with perioperative stroke. RESULTS: From 2013 to 2019, 327 CEA+D cases were identified and compared with 105,192 isolated CEA cases. The CEA+D patients were more likely to have undergone previous ipsilateral CEA (CEA, 1.8%; CEA+D, 4.9%; P < .01) and contralateral ICA occlusion (CEA, 4.6%; CEA+D, 11.0%; P < .01) but were less likely to have had ipsilateral stenosis ≥70% (CEA, 88.3%; CEA+D, 80.6%; P < .01). The preoperative factors associated with the need for CEA+D on multivariable analysis included previous peripheral vascular intervention, American Society of Anesthesiologists class ≥4, contralateral ICA occlusion, low-volume surgeon, and previous ipsilateral CEA. CEA+D was associated with significantly increased rates of stroke in both asymptomatic (CEA+D, 3.9%; CEA, 0.9%; P < .01) and symptomatic (CEA+D, 9.4%; CEA, 1.9%; P < .01) patients. CEA+D was associated with decreased rates of 30-day survival in both asymptomatic (CEA+D, 98.3%; CEA, 99.4%; P = .02) and symptomatic (CEA+D, 94.8%; CEA, 99.1%; P < .01) cohorts. On multivariable analysis, CEA+D remained significantly associated with stroke (odds ratio, 3.17; 95% confidence interval, 1.80-5.60; P < .01). Other factors significantly associated with perioperative stroke included procedure length >135 minutes, diabetes, hypertension, shunt for indication, symptomatic status, previous ipsilateral CEA, contralateral ICA occlusion, urgent or emergent procedure, intravenous medications for hemodynamic instability, and re-exploration at the initial operation. CONCLUSIONS: Although markers of more significant cardiovascular disease burden were associated with the use of CEA+D, their power to predict CEA+D use was limited. In cases in which CEA+D was used, CEA+D was associated with significantly greater rates of perioperative stroke and mortality compared with isolated CEA for both asymptomatic and symptomatic patients, which could be useful for framing the expected outcomes after these procedures.

Thoracofemoral bypass outcomes in the Vascular Quality Initiative.

OBJECTIVE: Thoracofemoral bypass (TFB) has been used infrequently but is an alternative for select patients with aortoiliac occlusive disease. Limited data are available in the reported data regarding TFB, with all studies small, single-center series. We aimed to describe the perioperative and long-term survival, patency, and rate of major perioperative complications after TFB in a large national registry. METHODS: The Vascular Quality Initiative suprainguinal bypass module was used to identify patients who had undergone TFB for occlusive disease from 2009 to 2019. A descriptive analysis was performed to provide the rates of survival, patency, major complications, and freedom from major amputation in the perioperative period and at 1 year of follow-up. Major complications were compared by procedure indication, with categorical variables analyzed using χ2 tests and continuous variables using analysis of variance. Kaplan-Meier curve analysis was used to estimate survival at the 1- and 5-year follow-up intervals and freedom from major amputation at 1 year. RESULTS: A total of 154 TFB procedures were identified. Of the 154 patients, 59 (38.3%) had undergone previous inflow bypass and 22 (14.2%) had undergone previous leg bypass. The procedure indications included claudication (n = 66; 42.9%), rest pain (n = 59; 38.3%), tissue loss (n = 19; 12.3%), and acute limb ischemia (n = 10; 6.5%). Major complications (eg, wound infection, respiratory, major stroke, new dialysis, cardiac, embolic, major amputation, occlusion) occurred in 31.2% of the cohort. When examined by indication, the acute limb ischemia and claudication cohorts had an increased rate of major complications (acute limb ischemia, 60.0%; claudication, 34.8%; critical limb ischemia, 24.4%; P = .05). The survival rate at 30 days was 95.5%, with a Kaplan-Meier estimated 1-year survival rate of 92.7% ± 2.2%. Primary patency at discharge from the index hospitalization was 92.9% and 89.0% at 1 year. Postoperative major amputation was required for 1 patient during the index hospitalization, for a Kaplan-Meier estimated freedom from major amputation at 1 year of 97.1% ± 2.2%. Two patients developed in-hospital bypass occlusion and three patients developed occlusion within 1 year, for an overall freedom from occlusion rate of 96.8% at 1 year. CONCLUSIONS: TFB is associated with a high rate of perioperative major complications; however, the long-term survival and patency after TFB remained acceptable when performed for limb salvage. The high perioperative complication rates of TFB procedures performed for claudication suggest TFB should be used rarely in this population. These data can be used to counsel patients and aid in decision making before operative intervention.

Describing Clinically Significant Arrhythmias in Postoperative Vascular Surgery Patients.

BACKGROUND: The American Heart Association guidelines instruct use of postoperative telemetry (POT) should be reserved for patients undergoing cardiac procedures and/or those with ischemic cardiac symptoms, but acknowledge that major vascular procedures deserve unique consideration. Telemetry remains a limited resource in many hospitals; however, it has been poorly defined which vascular patients have greatest need for POT. The purpose of this study is to define the rates of postoperative arrhythmias (POAs) after major vascular operations using the Society for Vascular Surgery Vascular Quality Initiative (VQI) registry, identify independent predictors of POA, and determine the effect of POA on mortality to guide the use of POT in vascular patients. METHODS: A retrospective cohort study was performed using the following VQI modules: open abdominal aortic aneurysm repair (oAAA), complex endovascular aneurysm repair (EVAR) (thoracic endovascular aortic repair [TEVAR]/c-EVAR), EVAR, suprainguinal bypass (SIB), and infrainguinal bypass (IIB). POA was defined in the VQI as a new rhythm disturbance requiring treatment with medication or cardioversion. The incidence of POA, preoperative risk factors, and demographics were determined for each procedure. RESULTS: A total of 121,652 procedures were identified with an overall POA event rate of 5.1% (n = 6,265). Procedure-specific event rates for POA among VQI registries are as follows: oAAA 14.4%, TEVAR/c-EVAR 8.5%, EVAR 2.7%, SIB 6.2%, and IIB 3.8%. Across all procedure types, POA was associated with emergent operations and increased procedure time. Procedure-specific multivariable regression revealed additional independent preoperative intraoperative factors associated with POA that were unique with each procedure. Across all procedural groups, the presence of POA was associated with increased rates of clinical myocardial infarction and decreased survival on Kaplan-Meier analysis. CONCLUSIONS: Rates of POA in patients undergoing vascular procedures appear higher than previously reported, and POA is associated with decreased survival. Our study elucidated patient- and procedure-specific predictor factors associated with POA that can be used to inform the use of POT.

The association between preoperative length of stay and surgical site infection after lower extremity bypass for chronic limb-threatening ischemia.

OBJECTIVE: Surgical site infection (SSI) is an important complication of lower extremity bypass (LEB) and the rate of SSI after LEB varies widely in the existing literature, ranging from 4% to 31%. Prolonged length of stay (LOS) has been implicated in the occurrence of SSI across multiple surgical disciplines. The impact of preoperative LOS in patients with chronic limb-threatening ischemia (CLTI) undergoing LEB is unknown. We examined the association of preoperative LOS on SSI after LEB. METHODS: A retrospective analysis of the Society for Vascular Surgery Vascular Quality Initiative Infrainguinal Bypass Registry identified patients undergoing elective LEB for chronic limb-threatening ischemia from 2003 to 2019. Patients undergoing LEB for acute limb ischemia, urgent/emergent procedures, aneurysm, or who had concomitant suprainguinal bypass were excluded. The primary outcome measure was postoperative SSI. Multivariable forward stepwise logistic regression was then performed including all variables with a P value of less than .10 in both matched and unmatched cohorts to evaluate for demographic and perioperative predictors of SSI. Propensity score matching was used to create matched cohorts of patients for each LOS group. RESULTS: A total of 17,883 LEB procedures were selected for inclusion: 0 days (12,362 LEB), 1 to 2 days (1737 LEB), and 3 to 14 days (3784 LEB). Patients with the greatest preoperative LOS were more likely to have vein mapping (0 days preoperative LOS, 66.3%; 1-2 days, 65.2%; 3-14 days, 73.2%; P < .01) or computed tomography angiography/magnetic resonance angiography (0 days, 32.1%; 1-2 days, 34.4%; 3-14 days, 38.4%; P < .01). Patients with 3 or more days of preoperative LOS had longer procedure lengths (0 days, 244 minutes; 1-2 days, 243 minutes; 3-14 days, 255 minutes; P < .01) and were more likely to have completion angiogram (0 days, 27.1%; 1-2 days, 29.5%; 3-14 days, 31.6%; P = .02). Multivariable logistic regression demonstrated that preoperative LOS of 3 to 14 days was associated with increased rate of SSI (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.20-3.07; P = .01). Transfusion of 3 or more units (OR, 2.87; 95% CI, 1.89-4.36; P < .01) and prolonged procedure length (>220 minutes; OR, 1.86; 95% CI, 1.26-2.73; P < .01) were also significantly associated with postoperative SSIs. CONCLUSIONS: Many factors including preoperative comorbidities and operative complexity covary with preoperative LOS as risk factors for SSI. However, when patients are matched based on comorbidities and factors that would predict overall clinical complexity, preoperative LOS remains important in predicting SSI.

Effects of statin and antiplatelet therapy noncompliance and intolerance on patient outcomes following vascular surgery.

OBJECTIVE: Prior studies have evaluated the effects of statin and antiplatelet agent (APA) medications on patients with peripheral arterial disease. Although the benefits of statin and APA use are well-described, there is a paucity of research into the specific outcomes of patients who are not compliant or those who are unable to take the medication owing to intolerance. Here we examine the outcomes of patients intolerant to statin and APA and compare them with patients who are compliant or noncompliant with these therapies. METHODS: Patients treated from 2005 to 2018 in the Vascular Quality Initiative registry were included. Patients with missing data or deaths within 30 days of procedure were removed. Patients were considered noncompliant if they were previously prescribed a medication at discharge but were not taking it at 1-year follow-up or if the patient was reported to be noncompliant in the registry. Medication intolerance was defined if listed as "no, for medical reasons," and mortality data were ascertained using the Social Security Death Index, which is regularly cross-referenced to the Vascular Quality Initiative registry. RESULTS: We identified 105,628 patients who met our inclusion criteria. Statin intolerance was noted in 2.3% at discharge and 2.1% at the 1-year follow-up, with 0.7% listed as intolerant at all stages. Factors associated with increased risk of intolerance to statins included female gender (P = .001), discharge APA intolerance (P = .004), insurance status (non-U.S. insurance) (P < .001), discharge APA noncompliance (P = .019), and discharge angiotensin converting enzyme inhibitor noncompliance (P = .005). Patients who were compliant with statins showed a 91% survival at 5 years vs 87% survival in noncompliant patients and 87% in intolerant patients at 5 years (P < .001). Patients with statin intolerance have a similar survival curve as noncompliant patients across all registry cohorts. Noncompliance with statins was correlated with noncompliance with APA medications (R = 0.16, P < .001). Factors associated with increased risk of statin noncompliance included preoperative ambulatory status (requiring assistance) (P = .039), female sex (P < .001), peripheral vascular intervention (P < .001) or infrainguinal open bypass procedure surgery (P = .001), discharge status (to nursing home) (P = .006) and insurance (self-pay) (P < .001). CONCLUSIONS: Patients not taking statin and APA medications have a substantially decreased 5-year survival irrespective of the reason for not taking. Importantly, patients noted to be intolerant have a similar survival curve as noncompliant patients across all registry cohorts. Intolerant patients may benefit from attempts to alter statin dose, type (hydrophilic vs lipophilic), or from newer agents such as PCSK9 inhibitors.

Factors Associated with Amputation after Peripheral Vascular Intervention for Intermittent Claudication.

BACKGROUND: The natural history of intermittent claudication (IC) is that only 25% of patients will experience worsening of their claudication symptoms, and only approximately 1-3% will progress to major amputation. The impact of increasing use of endovascular therapies on the natural history of IC has not been well established. The purpose of this study is to evaluate the incidence and identify predictors of major and minor amputations after peripheral vascular intervention (PVI) for IC. METHODS: A retrospective cohort of patients treated for IC was derived from the national PVI Vascular Quality Initiative database evaluating both preoperative and intraoperative variables from 2003 to 2017. We examined rates of major or minor amputations after ipsilateral PVI for IC. Multivariable logistic regression models were created to identify predictors of amputation along with Kaplan-Meier (KM) plots to estimate amputation-free survival. RESULTS: We identified 11,887 PVI procedures for patients undergoing elective treatment for IC without a previous history of lower extremity PVI or bypass. Major and minor amputations occurred at a combined rate of 1.08% (n = 128). Minor amputations occurred in 0.56% (n = 67) of patients at 1 year, whereas major amputations were reported in 0.51% (n = 61) of cases. KM plots of amputation-free survival revealed that patients with preoperative ankle brachial indexes (ABIs) <0.2 or noncompressible ABIs (>1.3) had significantly higher rates of any amputation compared with subjects with ABIs between 0.20-0.49, 0.50-0.89, and 0.90-1.30 (log rank, <0.001). Multivariate analysis showed that patients with preoperative symptomatic congestive heart failure (CHF) (odds ratio [OR], 6.48; 95% confidence interval [95% CI], 2.43-17.20; P < 0.001), American Society of Anesthesiologists (ASA) class IV (OR, 9.34; 95% CI, 1.94-44.89; P = 0.005), and nonwhite race (OR, 3.32; 95% CI, 1.50-7.36; P = 0.003) had significant increase in risk of major amputation after PVI. Odds of major or minor amputation were increased when patients underwent only a tibial-level intervention (major: OR, 6.26; 95% CI, 1.50-26.10; P = 0.012 and minor: OR, 7.04; 95% CI, 1.02-8.51; P = 0.001). CONCLUSIONS: With relation to amputation, the natural history of IC does not appear to be impacted by PVI sicker patients with higher ASA or symptomatic CHF, and those with isolated tibial interventions are at higher risk for amputation, and we cannot determine if this is due to patient substrate, presentation, or the intervention itself. Importantly, there are key prognostic preoperative and intraoperative indicators that can assist the clinician with predicting patients who are at a higher risk of amputation.

Importance of postprocedural Wound, Ischemia, and foot Infection (WIfI) restaging in predicting limb salvage.

OBJECTIVE: The Wound, Ischemia, and foot Infection (WIfI) classification system was created to encompass demographic changes and expanding techniques of revascularization to perform meaningful analyses of outcomes in the treatment of the threatened limb. The WIfI index is intended to be analogous to the TNM staging system for cancer, with restaging to be done after control of infection and after revascularization. Our goal was to evaluate the effectiveness of WIfI restaging after therapy in the prediction of limb outcomes. METHODS: Preoperative WIfI scoring was performed prospectively for all critical limb ischemia patients who underwent revascularization from January 2014 to June 2015. WIfI restaging and assessment of outcomes were performed retrospectively through August 2016. WIfI classification was determined at the following intervals: preoperatively, immediately postoperatively, and 1 month and 6 months after intervention. Amputation-free survival (AFS) was the primary end point. Kaplan-Meier plot analysis and comparisons of preoperative grades with respective postoperative grades were performed using paired t-test, χ2 test, and correlation analyses. RESULTS: A total of 180 limbs and 172 critical limb ischemia patients underwent revascularization, of which 29 limbs had major amputations (16%). Wound grades generally improved after surgery across the entire cohort. Major amputation was associated with preoperative wound grade and remained associated with wound grade at postoperative restaging at 1 month and beyond on the basis of amputation frequency analysis (preoperatively, 1 month, and 6 months, P = .03, < .001, and < .001, respectively). Wound grade was significantly associated with AFS at 1 month and 6 months after intervention (log-rank, P < .001 for restaging intervals). Ischemia grades improved initially with a slight decline across the cohort at 6 months. Ischemia grade at 1 month postoperatively was associated with AFS (log-rank, P = .03). Foot infection grades also improved at each time interval. Foot infection grade was associated with AFS at 1 month postoperatively (log-rank, P < .001) and at 6 months (log-rank, P = .017). CONCLUSIONS: WIfI restaging is an important tool for predicting limb loss and assessing adequacy of intervention, more so than baseline WIfI alone. The 1- and 6-month postoperative ischemia grade correlated with AFS, whereas preoperative grade did not. The 1- and 6-month postoperative wound and foot infection grades additionally correlated with AFS. WIfI restaging at 1 month and 6 months postoperatively may help identify a cohort that remains at higher risk for limb loss and may merit more expeditious reintervention.

Routine extended follow-up surveillance of iliac vein stents for iliocaval venous obstruction may not be warranted.

OBJECTIVE: The purpose of this study was to evaluate outcomes of iliac vein stents placed for iliocaval venous obstruction (ICVO) and to determine if routine follow-up surveillance is warranted on the basis of timing of stent failure. METHODS: All patients who underwent iliac vein stenting from 2003 to 2015 were identified from a prospectively maintained registry. Demographics of the patients, venous risk factors, prior venous interventions, indications, imaging, anatomic location of the ICVO, operative findings, procedural success, complications, and clinical follow-up were recorded. Clinical and ultrasound surveillance was performed at first postoperative follow-up and at routine subsequent intervals. Continuous data were analyzed with Student t-tests or Mann-Whitney U test, and frequency data were analyzed with χ2 analysis or Fisher exact test. Primary patency was analyzed using Kaplan-Meier survival analysis. RESULTS: Seventy-four limbs in 70 patients who underwent iliac vein stenting for ICVO were identified; 36 limbs (48.6%) were stented for nonthrombotic venous compression (stent-VC), and 38 limbs (51.4%) were stented for venous thrombosis (stent-VT). Twenty-seven limbs (71.1%) of the stent-VT group were treated for acute venous thrombosis requiring lysis followed by stenting for underlying venous lesions. The median number of follow-up visits for the stent-VC and stent-VT groups was two (interquartile range [IQR], 1-4) and two (IQR, 1-3), whereas the mean length of follow-up was 19.6 ± 29.5 months and 19.8 ± 26.5 months (P = .972), respectively. During the first 6 months, one limb (2.8% [n = 36]) in the stent-VC group occluded, whereas 13.2% (5/38) of the limbs in the stent-VT group occluded. In the stent-VT group, 57% of limbs (4 of 7) with acute venous thrombosis requiring thrombolytic therapy had limb occlusion at >6 months (median, 18.1 months; IQR, 16.6-30.1). Overall patency rates for the stent-VC and stent-VT groups were 97.2% (1/36) and 73.7% (10/38) at 36 months (standard error, ≤10%; P = .001), respectively. CONCLUSIONS: Iliac vein stents placed for nonthrombotic iliac vein compression had statistically higher patency than those placed for venous thrombosis, with few stent failures, all occurring within 6 months. Iliac vein stents placed for venous thrombosis continued with stent failure after 6 months and may benefit from extended surveillance.

Outcomes after celiac artery coverage during thoracic endovascular aortic aneurysm repair.

OBJECTIVE: Coverage of celiac artery (CA) during thoracic endovascular aortic aneurysm repair (TEVAR) has been performed to extend the distal seal zone for which preliminary results and short-term follow-up have been reported. We aim to show the outcomes up to 81 months after CA coverage during TEVAR. METHODS: Patients undergoing TEVAR with coverage of the CA origin from 2005 to 2013 were retrospectively analyzed. Points of analysis include indications for covering the CA, demonstration of collateral circulation between the CA and superior mesenteric artery (SMA), anatomic features of the distal landing zone, rate of reintervention, technical success, presence of clinical ischemic symptoms after the procedure, and mortality. RESULTS: During the 9-year period, 366 patients underwent TEVAR, 18 (5%) of whom had CA coverage. Eleven (61%) had TEVAR with CA coverage due to a thoracic aneurysm, three (17%) had thoracic aortic dissection related to aneurysm, and four (22%) had previous TEVAR with a type Ib endoleak (EL) requiring distal coverage. Mesenteric angiography in preparation for TEVAR with CA coverage diagnosed a critical SMA stenosis in one patient that was treated with stenting before the index procedure. At the conclusion of the indicated procedure, two patients (11%) had a type Ia EL and two patients (11%) had a type Ib EL. Three of the type I ELs required reintervention. Two patients (11%) had a type II EL, both of which were managed with observation and resolved. Reintervention was required in 27% of patients. Postoperative complications included visceral ischemia in 2 (11%), weight loss in 1 (5%), spinal cord ischemia in 2 (11%), a cerebrovascular event in 1 (6%), and death in 1 (6%). The mean follow-up period was 38 months (range, 0.5-81 months). CONCLUSIONS: This analysis of outcomes up to 81 months supports the suitability of covering the CA in selected patients for extending the distal landing zone to the visceral aortic level above the SMA or when alternative branch vessel treatment is unavailable. Preoperative angiographic evaluation of the mesenteric collaterals and early postoperative surveillance may limit postoperative complications. Once the CA is covered, new symptoms do not develop unless the SMA is compromised.

Factors affecting Cook Gunther Tulip and Cook Celect inferior vena cava filter retrieval success.

OBJECTIVE: Success rates vary for the retrieval of inferior vena cava filters (IVCFs). The optimal retrieval time and factors influencing retrieval success remain unproven. This study aims to determine optimal time and evaluate factors related to successful IVCF retrieval. METHODS: An institutional prospectively maintained database was reviewed for all IVCF retrieval attempts from 2006 to 2012. Patient demographics, comorbidities, indications for procedure, placement technique, IVCF type, presence of angulation, and time to retrieval were evaluated with respect to success or failure of retrieval. Statistical analyses (t-test, χ(2), correlations, and Kaplan-Meier plots) were performed comparing successful and unsuccessful retrievals. RESULTS: Of 121 attempted IVCF retrievals, 92 (76%) were successful and 29 (24%) were unsuccessful. There were no significant differences between the successful and unsuccessful attempts in terms of patient demographics, comorbidities, indications for procedure, placement technique, or IVCF type, which included 93 Celect (77%) and 28 Gunther Tulip (23%). Time since IVCF placement was significantly different (P = .025) between the successful and unsuccessful retrieval groups (medians were 105 [7-368] and 162 [43-379] days, respectively). Time since IVCF placement greater than 117 days correlated significantly with unsuccessful IVCF retrieval (R = 0.218; P = .017; odds ratio, 2.88; P = .02). Angulation greater than 20 degrees on anteroposterior radiograph was noted in seven of 29 (24%) unsuccessful retrievals compared with seven of 92 (8%) successful retrievals and was significant (P = .012). CONCLUSIONS: Cook Gunther Tulip and Celect IVCF retrieval is most likely to be successful within 3 to 4 months of placement. Unsuccessful retrieval attempts are more likely to occur when IVCF position is angulated.

Comparison of outcomes following endovascular repair of abdominal aortic aneurysms based on size threshold.

INTRODUCTION: Size threshold for operative repair of abdominal aortic aneurysms (AAAs) has been determined based on risks and outcomes of open repair vs surveillance. The influence of endovascular aneurysm repair (EVAR) on this threshold is less established. The purpose of this study is to determine whether long-term outcomes following EVAR are affected by maximum diameter at the time of treatment. METHODS: Patients undergoing EVAR with modular stent grafts from 2000 to 2011 were identified from a prospectively maintained database and stratified by maximum aortic diameter at the time of repair: small (4.0-4.9 cm), medium (5.0-5.9 cm), and large (≥6.0 cm). Comparisons of demographics, indications for repair, perioperative complications, and long-term outcomes were made using analysis of variance, χ(2), and Kaplan-Meier plots. RESULTS: Seven hundred forty patients were identified: 157 (21.2%) small, 374 (50.5%) medium, and 209 (28.2%) large. Patients differed by mean age (69.3 ± 8.09, 71.7 ± 8.55, and 73.6 ± 8.77 years for small, medium, and large, respectively; P < .001), coronary artery disease (42% small, 57% medium, 51.2% large; P = .01), prior coronary angioplasty (14.6% small, 18.2% medium, 9.6% large; P = .02), congestive heart failure (5.7% small, 15.2% medium, 19.6% large; P = .01), prior vascular surgery (7% small, 15.8% medium, 10% large; P = .016), and chronic obstructive pulmonary disease (21% small, 27% medium, 33% large; P = .038). Small AAAs were more frequently symptomatic (19.7% small, 7.5% medium, 8.1% large; P < .001). There was no difference in perioperative complication rates (P = .399), expansion ≥5 mm (2.6% small, 5.6% medium, 7.2% large; P = .148), or all-type endoleak (40.8% small, 41.7% medium, 44.5% large; P = .73). Small AAAs developed fewer type I endoleaks (5.1% vs 6.95% medium and 14.8% large; P = .001). Compared with small AAAs, both medium (P = .39) and large (P < .001) required secondary intervention more frequently, with hazard ratios of 2.32 (95% confidence interval, 1.045-5.156) and 4.74 (95% confidence interval, 2.115-10.637), respectively. Ten-year survival was 72%, 63.1%, and 49.8% in the small, medium, and large groups, respectively (P < .001) with one rupture-related death after EVAR in the large group. All-cause mortality differed among the 75- to 84-year-old patients (30.4% small, 51.6% medium, 55.7% large; P = .017). CONCLUSIONS: EVAR for small AAAs shows improved long-term outcomes than for age-matched patients with larger aneurysms.

Effect of lipid-modifying drug therapy on survival after abdominal aortic aneurysm repair.

BACKGROUND: Lipid-modifying drug therapy (LMDT) is recommended in all patients having coronary or noncoronary atherosclerotic disease. However, the effect of LMDT after abdominal aortic aneurysm (AAA) repair, especially in the absence of other atherosclerotic manifestations, is unclear. We examined the distribution of prevalence of LMDT among patients undergoing AAA repair and its effect on survival in the presence and absence of other atherosclerotic diseases. METHODS: We identified patients treated at University of Alabama at Birmingham between 1985 and 2010 who had a prior AAA repair. Information was collected from health system medical charts, medical communication, and national death indices. We assessed the predictors of prevalence of LMDT by univariate analysis using t-test for continuous and χ(2) test for categorical variables, and then performed multivariate logistic regression. The survival was determined using Kaplan-Meier plots, and adjusted hazard ratios were calculated using Cox proportion regression. RESULTS: A total of 2063 patients underwent AAA repair procedure. Of these, 9% were African-American, and 20% were female. Thirty-five percent received LMDT, and 32% died during the follow-up period of up to 240 months. Significant predictors for being on LMDT included white race (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.2), presence of other atherosclerotic disease or diabetes (OR, 2.4; 95% CI, 1.9-3.0), hypertension (OR, 4.0; 95% CI, 3.1-5.2), smoking (OR, 1.6; 95% CI, 1.2-2.1), and endovascular AAA repair (OR, 1.9; 95% CI, 1.5-2.3). LMDT was associated with improved survival (hazard ratio, 0.6; 95% CI, 0.5-0.8) after controlling for traditional risk factors, diabetes, and other atherosclerotic diseases. CONCLUSIONS: LMDT after AAA is associated with an increased survival compared with patients who were not using drug therapy for dyslipidemia. Aggressive management of dyslipidemia should be considered in all patients undergoing AAA repair irrespective of other atherosclerotic disease status and risk factor profile.

Risk scoring system to predict 3-year survival in patients treated for asymptomatic carotid stenosis.

OBJECTIVE: To identify risk factors and stratify their effect of compromising 3-year survival in patients treated for asymptomatic carotid disease based upon recently updated guidelines from the Society for Vascular Surgery. METHODS: Outcomes of 506 patients who underwent carotid intervention for asymptomatic carotid disease (1999-2008) were analyzed. Hospital computerized medical records were reviewed. When local records were sparse, Social Security Death Index was queried to confirm mortality. Following multivariable Cox regression analysis, a score was assigned based on the calculated hazard ratio (HR) in the following fashion: HR 1.5-1.9 = 1 point; HR 2.0-3.0 = 2 points; and HR >3 = 3 points. The sum of those points comprised the final score for each patient. Kaplan-Meier analyses were then performed to delineate survival differences. RESULTS: Seventy patients (13.83%) did not survive beyond 3 years after the procedure. Age >80 years (HR, 1.79; P = .05; score 1), diabetes mellitus (HR, 1.99; P < .05; score 1), coronary artery intervention (HR, 2.03; P < .01; score 2), severe chronic kidney disease defined as glomerular filtration rate <30 and not on dialysis (HR, 2.46; P = .03; score 2), dialysis patients (HR, 5.67; P = .001; score 3), and chronic obstructive pulmonary disease (HR, 3.53; P < .001; score 3) negatively influenced 3-year survival. Patients with score ≤2 experienced 3-year mortality of 6.0%, whereas score >2 was associated with 31.6% 3-year mortality (HR, 6.10; P < .001). The score value was not associated with the stroke rate at any time point. The resultant score was validated in a separate population of patients with symptomatic carotid disease. CONCLUSIONS: This easy predictive score underscores the association of medical risk factors with decreased 3-year survival. This finding may impact future clinical decisions for management of asymptomatic carotid disease.

Protocol implementation of selective postoperative lumbar spinal drainage after thoracic aortic endograft.

BACKGROUND: Spinal cord ischemia (SCI) remains a significant concern in patients undergoing endovascular repair involving the thoracic aorta (thoracic endovascular aortic repair [TEVAR]). Perioperative lumbar spinal drainage has been widely practiced for open repair, but there is no consensus treatment protocol using lumbar drainage for SCI associated with TEVAR. This study analyzes the efficacy of an institutional protocol using selective lumbar drainage reserved for patients experiencing SCI following TEVAR. METHODS: A prospectively maintained registry was reviewed to identify all patients who underwent TEVAR from January 2000 through June 2010. Preoperative characteristics, intraoperative details, and outcomes, including neurologic deficit and mortality at 30 days and 1 year were determined based on reporting standards. Patients developing symptoms of SCI in the postoperative setting were compared with those without neurologic symptoms. SCI patients who received selective lumbar drainage were grouped based on resolution of neurologic function, with risk factors and outcomes of these subgroups analyzed with χ(2), t test, logistic regression, and analysis of variance (ANOVA). RESULTS: Two hundred seventy-eight TEVARs were performed on 251 patients. Twelve patients accounting for 12 TEVARs were excluded from analysis: 5 patients experienced SCI preoperatively, 4 patients were drained preoperatively, 2 expired intraoperatively, and 1 procedure was aborted. Of the remaining 266 procedures in 239 patients, 16 (6.0%) developed SCI within the 30-day postoperative period. Risk factors for SCI reaching statistical significance included length of aortic coverage (P = .036), existence of infrarenal aortic pathology (P = .026), and history of stroke (P = .043). Stent graft coverage of the left subclavian artery origin was required in 28.9% (n = 77) and was not associated with SCI (P = .52). Ten of 16 post-TEVAR SCI patients received selective postoperative lumbar drains and were categorized based on resolution of symptoms into complete resolution (n = 3; 30%), partial resolution (n = 4; 40%), and no resolution (n = 3; 30%). No patient characteristics or risk factors reached significance in comparison of lumbar drained patients and nondrained patients. All seven drained patients without complete resolution of SCI died within the first year after surgery, while all three of the complete responders survived (P = .017). In patients with SCI, increased all-cause mortality was observed at 1 year (56.3% vs 20.4%; P = .003). CONCLUSIONS: A protocol utilizing selective postoperative lumbar spinal drainage can be used safely for patients developing SCI after TEVAR with acceptably low permanent neurologic deficit, although overall survival of patients experiencing SCI after TEVAR is diminished relative to non-SCI patients.