Impact of frailty on risk of long-term functional decline following vascular surgery.

OBJECTIVE: Frailty is a clinical syndrome associated with slow recovery after vascular surgery. However, the degree and length of functional impairment frail patients experience after surgery is unclear. The objective of this study was to prospectively measure changes in functional status among frail and non-frail patients undergoing a spectrum of different vascular surgery procedures. METHODS: Patients consented to undergo elective minor and major vascular surgery procedures at an academic medical center between May 2018 and March 2019 were prospectively identified. Prior to surgery, all patients underwent provider assessment of frailty using the validated Clinical Frailty Scale (CFS), as well as baseline assessment of functional status using the Katz Activities of Daily Living (ADL) index and the Lawton Instrumental Activities of Daily Living (iADL) index. These same instruments were used to evaluate each patient's functional status at 2-weeks, 1-month, 1-year, and 2-year time points following surgery. Changes in iADL and ADL scores among frail (CFS ≥5) and non-frail patients were compared using paired Wilcoxon signed-rank tests and logistic regression models. RESULTS: A total of 126 patients were assessed before and after minor (55%) and major (45%) vascular procedures, of which 43 patients (34%) were determined to be frail prior to surgery. Frail patients were older and more likely than non-frail patients to have medical comorbidities including chronic kidney disease, chronic obstructive pulmonary disease, or diabetes (all P < .05). When compared with the non-frail cohort, frail patients had significantly lower ADL and iADL scores before surgery and experienced a greater decline in ability to independently complete ADL and iADL activities after surgery that was sustained at 2 years (P < .05 and P < .001, respectively). After risk-adjustment, frailty was associated with an increased likelihood of decline in ADLs (odds ratio, 5.4; 95% confidence interval, 1.9-15.4; P < .05) and iADLs (odds ratio, 6.3; 95% confidence interval, 2.6-15.1; P < .001) at 2 years following surgery. CONCLUSIONS: Frail patients experience a significant decline in ability to perform ADL and iADLs that persists 2 years following vascular surgery. These data highlight the degree of functional decline occurring immediately following surgery, as well as risk for long-term, sustained impairment that should be shared with frail patients before undergoing a procedure.

High-intensity statin therapy reduces risk of amputation and reintervention among patients undergoing lower extremity bypass for chronic limb-threatening ischemia.

OBJECTIVE: Statins are considered standard-of-care medical therapy for patients undergoing lower extremity bypass (LEB) procedures for chronic limb-threatening ischemia (CLTI). It is unclear, however, whether up-titrating and maintaining patients on higher-intensity statin medications following LEB improves limb salvage outcomes. This study was designed to evaluate whether high-intensity statin therapy impacts the risk of amputation and reintervention following LEB for patients with CLTI. METHODS: The IBM MarketScan database was used to identify adult patients (18-99 years old) who underwent a LEB for CLTI between 2008 and 2017. Patients lacking insurance covering drug reimbursement or those who already had undergone amputation before time of bypass were excluded. Using pharmacy claims and national drug codes to define statin intensity, patients were stratified into three groups: high-intensity, low-intensity, and limited statin therapy. The association between intensity of statin therapy and need for reintervention and/or major amputation after LEB was analyzed using Kaplan-Meier curves and risk-adjusted Cox proportional hazard models. RESULTS: A total of 25,907 patients who underwent LEB for CLTI were identified, of which 6696 (26%) were maintained on high-dose statins, 9297 (36%) were on low-dose statins, and 9914 (38%) had inconsistent pharmacy claims for statin therapy after surgery. Patients on high-intensity statins were, on average, younger and more likely to be male with comorbid disease (diabetes, hypertension, hyperlipidemia, obesity, renal insufficiency, ischemic heart disease, cerebrovascular disease, and tobacco abuse) than patients on low-intensity statins or limited statin therapy (P < .001 for all comparisons). Following LEB, 6649 patients (25.6%) required a reintervention, and 2550 patients (9.8%) went on to have a major amputation during follow-up. Patients maintained on high-intensity statins after LEB had a significantly lower likelihood of requiring a reintervention (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.45-0.51; P < .001) or amputation (HR, 0.27; 95% CI, 0.24-0.30; P < .001) as compared with patients on limited statin therapy. Further, there was a dose-dependent effect for these outcomes relative to patients on low-intensity statins in risk-adjusted models, and it was independent of whether an autologous vein graft was used for the LEB. Finally, among patients who underwent a reintervention, high-dose statin therapy also significantly reduced the HR for subsequent amputation (HR, 0.21; 95% CI, 0.18-0.25; P < .001). CONCLUSIONS: Patients with CLTI on high-intensity therapy following LEB had a significantly lower risk of requiring subsequent reintervention and amputation when compared with patients on low-intensity statins or with limited statin use. These data suggest that patients with CLTI should be up-titrated and/or maintained on high-intensity statins following revascularization whenever possible.

Predictors of Arteriovenous Fistula Maturation among Patients with Severe Obesity.

BACKGROUND: There is an increasing prevalence of obesity among patients who develop end-stage renal disease and require dialysis. While referrals for arteriovenous fistulas (AVFs) among patients with class 2-3 obesity (i.e., body mass index [BMI] ≥ 35) are increasing, it is unclear what type of autogenous access is most likely to mature in this patient population. This study was designed to evaluate factors that impact maturation of AVF among patients with class ≥2 obesity. METHODS: We retrospectively reviewed AVFs created at a single center from 2016 to 2019 for patients who had undergone dialysis within the same healthcare system. Ultrasound studies were used to evaluate factors that defined functional maturation, including diameter, depth, and volume flow rates through the fistula. Logistic regression models were used to evaluate the risk-adjusted association between class ≥2 obesity and functional maturation. RESULTS: A total of 202 AVFs [radiocephalic (24%), brachiocephalic (43%), and transposed brachiobasilic (33%)] were created during the study period, of which 53 (26%) patients had a BMI >35. Functional maturation was significantly lower among patients with class ≥2 obesity undergoing brachiocephalic (58% obese versus 82% normal-overweight; P = 0.017), but not radiocephalic or brachiobasilic AVFs. This was primarily a result of excessive AVF depth in severely obese patients (9.6 ± 4.0 mm obese versus 6.0 ± 2.7 mm normal-overweight; P < 0.001), whereas there was no significant difference found in average volume flow or AVF diameter between groups. In risk-adjusted models, a BMI ≥35 was associated with a significantly lower likelihood of achieving AVF functional maturation (odds ratio: 0.38; 95% confidence interval: 0.18-0.78; P = 0.009) after controlling for age, sex, socioeconomic status, and fistula type. CONCLUSIONS: Patients with a BMI >35 are less likely to mature AVFs after creation. This principally affects brachiocephalic AVFs and occurs because of increased fistula depth as opposed to diameter or volume flow parameters. These data can help guide decision-making when planning AVF placement in severely obese patients.

Rules of 6 criteria predict dialysis fistula maturation but not all rules are equal.

OBJECTIVE: The Rules of 6 (flow volume >600 mL/min, vein diameter >6 mm, vein depth <6 mm) are widely used to determine when an arteriovenous fistula (AVF) will support dialysis. Thus, we tested the utility of the Rules of 6 in clinical practice. METHODS: We retrospectively reviewed AVFs created at a single center from 2016 to 2019 for patients who had undergone dialysis within the same healthcare system. Clinical records and postoperative ultrasound studies were reviewed for the Rules of 6 criteria. Maturation was defined as use of the AVF with two needles for 75% of the dialysis sessions for a continuous 4-week period, with a mean flow of 300 mL/min or urea clearance (Kt/V) of 1.2. Predictors of maturation were assessed using logistic regression and receiver operating characteristic (ROC) curves. RESULTS: Five surgeons performed 202 AVFs of three types during 2016 to 2019 (radial-cephalic, n = 49; brachial-cephalic, n = 87; brachial-basilic, n = 66). Maturation occurred in 150 AVFs (74%; primary, n = 101 [50%]; assisted, n = 49 [24%]), while 52 (26%) failed to mature. Maturation did not vary by AVF type or patient sex or diabetes status. A higher body mass index was associated with failure to mature (P = .004). Only 16 mature AVFs (11%) met all three Rules of 6 using mean values for flow, diameter, and depth. However, 101 (67%) met all three Rules using the extreme, maximum or minimum, values. On multivariate analysis, each Rule of 6 was independently associated with maturation. If all three Rules were met, the AVF was nearly 10-fold more likely to have matured compared with an AVF satisfying no Rule. The body mass index correlated strongly with the vein depth (P < .001); however, both characteristics independently predicted maturation. The chance of maturation was highest if flow and depth Rules were met (positive predictive value [PPV], 93%); if all three rules were met, the PPV was 92%. The ROC area under curve (AUC) values for meeting flow volume and vein depth Rules together were higher than if all three Rules had been satisfied (0.784 vs 0.754). The PPV for diameter alone (78%) was the lowest of all PPVs for the three Rules and the ROC-AUC was only 0.588. If all three Rules together were not satisfied using extreme values, the negative predictive value was only 47%. CONCLUSIONS: The Rules of 6 predict AVF maturation, especially when using extreme, maximum or minimum, values to satisfy each Rule. Flow volume and vein depth together predict maturation equally as well as meeting all three Rules. Vein diameter seems less important. The Rules of 6 might be too stringent if used exclusively to predict for functional AVF maturation.

A Vascular Quality Initiative frailty assessment predicts postdischarge mortality in patients undergoing arterial reconstruction.

BACKGROUND: Frailty assessment adds important prognostic information during preoperative decision-making but can be cumbersome to implement into routine clinical care. We developed and tested an abbreviated method of frailty assessment using variables routinely collected by the Vascular Quality Initiative (VQI) registry. METHODS: An abbreviated frailty score (the simple Vascular Quality Initiative-Frailty Score [VQI-FS]) was developed using 11 or fewer VQI variables (hypertension, congestive heart failure, coronary artery disease, peripheral vascular disease, diabetes, chronic obstructive pulmonary disease, renal impairment, anemia, underweight, nonhome residence, and nonambulatory status) that map to recognized frailty domains in the Comprehensive Geriatric Assessment and the literature. Nonemergent cases registered in the VQI from 2010 to 2017 (n = 265,632) in seven registries (carotid endarterectomy, n = 77,111; carotid artery stenting, n = 13,215; endovascular abdominal aortic aneurysm repair, n = 29,607; open abdominal aortic aneurysm repair, n = 7442; infrainguinal bypass, n = 33,128; suprainguinal bypass, n = 10,661; and peripheral vascular intervention, n = 94,468) were analyzed using logistic regression models to determine the predictive power of the VQI-FS for perioperative and longer term (9-month) mortality. Nomograms were created using weighted regression coefficients to assist in individualized frailty assessment and estimation of 9-month mortality. RESULTS: The VQI-FS, using equal weighting of these 11 VQI variables, effectively predicted 9-month mortality with an area under the curve of 0.724 by receiver operating characteristic curve analysis. However, differential weighting of the variables allowed simplification of the model to only seven variables (congestive heart failure, renal impairment, chronic obstructive pulmonary disease, not living at home, not ambulatory, anemia, and underweight status); hypertension, coronary artery disease, peripheral vascular disease, and diabetes had relatively low predictive power. Adding procedure-specific risk further improved performance of the model with a final area under the curve on receiver operating characteristic curve analysis of 0.758. Model calibration was excellent with predicted/observed regression line slope of 0.991 and intercept of 5.449e-04. CONCLUSIONS: A differentially weighted abbreviated VQI-FS using seven variables in addition to procedure-specific risk has strong correlation with 9-month mortality. Nomograms incorporating patient- and procedure-adjusted risk can effectively predict 9-month mortality. Reliable estimates of longer term mortality should assist in preoperative decision-making for vascular procedures that often carry substantial risk of mortality.

Society for Vascular Surgery appropriate use criteria for management of intermittent claudication.

The Society for Vascular Surgery appropriate use criteria (AUC) for the management of intermittent claudication were created using the RAND appropriateness method, a validated and standardized method that combines the best available evidence from medical literature with expert opinion, using a modified Delphi process. These criteria serve as a framework on which individualized patient and clinician shared decision-making can grow. These criteria are not absolute. AUC should not be interpreted as a requirement to administer treatments rated as appropriate (benefit outweighs risk). Nor should AUC be interpreted as a prohibition of treatments rated as inappropriate (risk outweighs benefit). Clinical situations will occur in which moderating factors, not included in these AUC, will shift the appropriateness level of a treatment for an individual patient. Proper implementation of AUC requires a description of those moderating patient factors. For scenarios with an indeterminate rating, clinician judgement combined with the best available evidence should determine the treatment strategy. These scenarios require mechanisms to track the treatment decisions and outcomes. AUC should be revisited periodically to ensure that they remain relevant. The panelists rated 2280 unique scenarios for the treatment of intermittent claudication (IC) in the aortoiliac, common femoral, and femoropopliteal segments in the round 2 rating. Of these, only nine (0.4%) showed a disagreement using the interpercentile range adjusted for symmetry formula, indicating an exceptionally high degree of consensus among the panelists. Post hoc, the term "inappropriate" was replaced with the phrase "risk outweighs benefit." The term "appropriate" was also replaced with "benefit outweighs risk." The key principles for the management of IC reflected within these AUC are as follows. First, exercise therapy is the preferred initial management strategy for all patients with IC. Second, for patients who have not completed exercise therapy, invasive therapy might provide net a benefit for selected patients with IC who are nonsmokers, are taking optimal medical therapy, are considered to have a low physiologic and technical risk, and who are experiencing severe lifestyle limitations and/or a short walking distance. Third, considering the long-term durability of the currently available technology, invasive interventions for femoropopliteal disease should be reserved for patients with severe lifestyle limitations and a short walking distance. Fourth, in the common femoral segment, open common femoral endarterectomy will provide greater net benefit than endovascular intervention for the treatment of IC. Finally, in the infrapopliteal segment, invasive intervention for the treatment of IC is of unclear benefit and could be harmful.

Vascular surgery triage during the coronavirus disease 2019 pandemic.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has resulted in a marked increase in hospital usage, medical resource scarcity, and rationing of surgical procedures. This has created the need for strategies to triage surgical patients. We have described our experience using the American College of Surgeons (ACS) COVID-19 guidelines for triage of vascular surgery patients in an academic surgery practice. METHODS: We used the ACS guidelines as a framework to direct the triage of vascular surgery patients during the COVID-19 pandemic. We retrospectively analyzed the results of this triage during the first month of surgical restriction at our hospital. Patients undergoing surgery were identified by reviewing the operating room schedule. We reviewed the electronic medical records (EMRs) and assigned an ACS category, condition, and tier class to each completed surgery. Surgeries that were postponed during the same period were identified from a prospectively maintained list. We reviewed the EMRs for all postponed surgeries and assigned an ACS category, condition, and tier class to each surgery. We reviewed the EMRs for all postponed procedures to identify any adverse events related to the treatment delay. RESULTS: We performed 69 surgeries in 52 patients during the study period. All surgeries were performed to treat emergent, urgent, or time-sensitive elective diagnoses. Of the 69 surgeries, 47 (68%) were from tier 3 and 22 (32%) from tier 2b. We did not perform any surgeries from tier 1 or 2a. We postponed surgery for 66 patients during the same period, of which 36 (55%) were from tier 1, 22 (33%) from tier 2a, 5 (8%) from tier 2b, and 3 (5%) could not be assigned a tier class. No tier 3 surgeries were postponed. Of the 66 patients, 3 (4.5%) experienced an adverse event that could be attributed to the treatment delay. CONCLUSIONS: The ACS triage guidelines provided an effective method to decrease vascular surgical volumes during the COVID-19 pandemic without an increase in patient morbidity. We believe the clinical utility of the guidelines would be strengthened by incorporating the SURGCON/VASCCON (surgical activity condition/vascular activity condition) threat level alert system.

Predictors of Adherence to Anti-Impulse Therapy among Patients Treated for Acute Type-B Aortic Dissections.

BACKGROUND: Medical management remains the mainstay of treatment for patients who present with acute Type-B aortic dissections (TBAD). However, it is unclear whether patients maintain adherence to their anti-impulse therapy medication regimen following hospital discharge. This study was designed to evaluate rates and predictors of medication adherence among insured patients treated for acute TBAD. METHODS: We used the Truven MarketScan database to identify US patients who presented with an acute TBAD between 2008 to 2017. Patients with continuous health insurance (Commercial or Medicare Part C) for at least 12 months after TBAD diagnosis were stratified by whether they underwent open surgical repair (OPEN), thoracic endovascular aortic repair (TEVAR), or only medication management (MED). Prescriptions for anti-impulse therapy medications were captured and adherence was defined by the medication possession ratio as > 80% fill rate over the follow-up period. Mixed-effects logistic regression models were used to identify predictors for medication adherence. RESULTS: A total of 6,702 patients were identified that underwent treatment for TBAD (3% TEVAR, 9% OPEN, & 74% MED), whereas 14% received no intervention. The overall mean (±SD) rate of adherence to anti-impulse therapy was 72.6% ( ± 26), and varied based on type of TBAD intervention (73.4% TEVAR, 74.4% OPEN, & 72.4% MED). The majority of patients across all treatment groups were prescribed ≥ 2 agents, with beta-blockers and diuretics being the most common medication classes. The odds of adherence to anti-impulse therapy were significantly lower for patients who were female (OR: 0.93; 95%CI:0.85-0.99; P = 0.03), aged < 45 years (OR: 0.81; 95%CI:0.69-0.96; P < 0.001), nonadherent on preexisting therapy (OR: 0.81; 95%CI: 0.73-0.89; P < 0.001), and when medications were obtained in less than a 90 days supply from retail pharmacies. CONCLUSIONS: Nearly a quarter of patients were nonadherent with anti-impulse therapy prescribed following an acute TBAD, which was more likely among younger female patients not adherent before their event. Adherence was improved among patients who received their medications by mail and when a > 90 days supply was prescribed. These findings may be used by quality improvement initiatives to improve medication adherence following TBAD and help prevent further complications.

Long-Term Impact of Vascular Surgery Stress on Frail Older Patients.

BACKGROUND: Frailty is a syndrome where the ability to cope with acute physiological stress is compromised, although it is unclear what impact this stress has on long-term outcomes. Vascular-Physiological and Operative Severity Score for enumeration of Mortality and Morbidity is a validated method for calculating levels of stress associated with vascular procedures. We designed this study to evaluate the long-term impact of different levels of surgical stress among frail older patients undergoing vascular surgery procedures. METHODS: We identified all independently living patients who underwent prospective frailty assessment followed by an elective vascular surgery procedure captured in the Vascular Quality Initiative registry (endovascular abdominal aortic aneurysm [AAA] repair, thoracic endovascular aortic repair, suprainguinal and infrainguinal bypass, peripheral vascular intervention, carotid endarterectomy, and open AAA) at an academic institution between January 2016 and July 2018. Patient- and procedure-level data were obtained from our institutional data warehouse and Vascular Quality Initiative database, and used to calculate Vascular-Physiological and Operative Severity Score for enumeration of Mortality and Morbidity scores. The association between frailty and composite outcome of any major complications (surgical site infection; graft thrombectomy; major amputation; adverse cardiac, pulmonary, or neurologic event; acute renal insufficiency; and/or reoperation related to the index procedure), nonhome living status, or death within 1 year after low-, medium-, and high-stress vascular procedures was evaluated using bivariate and logistic regression models. RESULTS: A total of 163 patients were identified (70% male, mean age 67.8 years) who underwent open AAA repair (6%), endovascular AAA repair (21%), thoracic endovascular aortic repair (7%), suprainguinal bypass (5%), infrainguinal bypass (18%), carotid endarterectomy (18%), or peripheral vascular interventions (25%), which included 44 (27%) patients diagnosed with frailty before surgery. Overall, frail patients had significantly higher rates of the 1-year composite outcome (48% frail versus 27% nonfrail; P = 0.012) when compared with nonfrail patients, with a significant dose-dependent effect as the level of stress increased. In comparison, increasing levels of surgical stress had a negligible effect on long-term outcomes among nonfrail patients. The interaction between frailty and high surgical stress was found in adjusted regression models to be a significant predictor of adverse outcomes within 1 year after vascular surgery (odds ratio, 3.3; 95% confidence interval, 1.3-8.6; P < 0.01). CONCLUSIONS: Frail patients who undergo high-stress vascular procedures have a significantly higher rate of complications leading to loss of functional independence and mortality within the year after their surgery. These data suggest that estimates of surgical stress should be incorporated into clinical decision making for frail older patients before and after surgery.

Vascular Quality Initiative assessment of compliance with Society for Vascular Surgery clinical practice guidelines on the care of patients with abdominal aortic aneurysm.

OBJECTIVE: Professional societies publish clinical practice guidelines to provide evidence-based recommendations to improve care and to reduce practice variation. However, the degree of compliance with the guidelines and its impact on outcomes have not been well defined. This study used the Vascular Quality Initiative (VQI) abdominal aortic aneurysm (AAA) registries to determine current compliance with and impact of recent Society for Vascular Surgery (SVS) AAA guidelines. METHODS: Recommendations from the SVS AAA guidelines were reviewed and assessed as to whether they could be evaluated with current VQI data sets. The degree of compliance with these individual recommendations was calculated by center and correlated with clinical outcomes. Data were analyzed by univariate analysis and mixed effects multivariable logistic regression. Statistical significance was measured at P < .05. RESULTS: Of the 111 SVS recommendations, 10 could be evaluated using VQI registries. The mean center-specific compliance rate ranged from 40% (smoking cessation 2 weeks before open AAA [OAAA] repair) to 99% (preservation of flow to one internal iliac artery during endovascular aneurysm repair [EVAR]). Some recommendations were associated with improved outcomes (eg, cell salvage for OAAA repair and antibiotic prophylaxis), whereas others were not (eg, EVAR at a center with >10 cases per year or door-to-intervention time <90 minutes for ruptured AAA). With multivariable analysis, compliance with preservation of flow to the internal iliac artery decreased major adverse cardiac events in EVAR and marginally decreased in-hospital and 1-year mortality in OAAA repair. Antibiotic administration decreased surgical site infection, major adverse cardiac events, and in-hospital mortality and marginally decreased respiratory complications and 1-year mortality in EVAR. Cell salvage for OAAA repair decreased 1-year mortality. Tobacco cessation before EVAR or OAAA repair decreased respiratory complications and 1-year mortality. CONCLUSIONS: The VQI registry is a valuable tool that can be used to measure compliance with SVS AAA guidelines. Compliance with recommendations was associated with improved outcomes and should be encouraged for providers. Participation in the VQI registry provides an objective assessment of performance and compliance with guidelines. VQI provider and center reports may be used as a focus for quality improvement efforts.

Failure on a Vascular Surgery Board-American Board of Surgery Examination does not predict cardiovascular outcomes in the Society for Vascular Surgery Vascular Quality Initiative.

OBJECTIVE: The Vascular Surgery Board of the American Board of Surgery (VSB-ABS) Qualifying and Certifying examinations are meant to assess qualifications to independently practice vascular surgery, but it is unclear whether examination performance correlates with clinical outcomes. We assessed this relationship using clinical outcomes data for VSB-ABS diplomates from the Society for Vascular Surgery Vascular Quality Initiative (SVS-VQI). METHODS: VSB-ABS examination performance for vascular surgeons participating in the SVS-VQI registry was characterized according to pass/fail status. Surgical experience was measured by number of years since completion of training. Examination performance and experience were compared with a composite clinical outcome (in-patient major adverse cardiac events or postoperative death [MACE+POD]) after arterial reconstructions (carotid stenting or endarterectomy, aortic aneurysm repair, open peripheral surgical bypasses) registered in the SVS-VQI. Multivariate mixed effects regression was performed adjusting for sex and surgery type, as well as clustering by surgeon and by hospital. RESULTS: From 2003 to 2017, complete data were available for 776 vascular surgeons who performed 124,171 arterial reconstructions (carotid n = 56,650; aortic n = 34,764; peripheral n = 32,757) registered in the SVS-VQI. Patient characteristics associated with higher odds of MACE+POD were female sex (odds ratio [OR] 1.07; 95% confidence interval [CI], 1.03-1.12; P = .006) and advancing age (OR, 1.04; 95% CI, 1.03-1.04; P < .001). Of the 776 surgeons, 149 (17%) had failed at least one VSB-ABS examination (group F). The unadjusted primary composite outcome of MACE+POD was marginally higher after operations performed by surgeons who never failed an examination (group P; 7% vs 6%; P = .03). This difference seems to be driven by higher rates of postoperative congestive heart failure in the aortic and lower extremity bypass cohorts as well as more postoperative myocardial infarctions after lower extremity bypass by group P surgeons. Following multivariable analyses, examination pass status was not associated with MACE+POD (OR, 0.98; 95% CI, 0.89-1.50; P = .517). However, increasing surgical experience correlated with significantly lower odds of MACE+POD (2% lower odds/year of experience since training [OR, 0.98; 95% CI, 0.98-0.99; P < .001]). CONCLUSIONS: VSB-ABS examination performance by SVS-VQI surgeons does not correlate with registry-reported mortality or cardiovascular complications. Increasing surgical experience is strongly associated with lower odds of cardiovascular morbidity and death.

Cost-effectiveness of repeated interventions on failing arteriovenous fistulas.

OBJECTIVE: Arteriovenous fistulas (AVFs) used for hemodialysis commonly undergo multiple percutaneous and open interventions to maintain functional patency, but it is unclear whether this strategy is cost-effective. The aim of this study was to evaluate the clinical effectiveness and cost-effectiveness of performing repeated interventions vs starting a new AVF. METHODS: We reviewed all patients with mature radiocephalic, brachiocephalic, and brachiobasilic AVFs at a single academic institution between 2007 and 2015 and assessed the clinical effectiveness of each open and percutaneous intervention to maintain functional patency after the fistula was created. These data were used to parameterize a Markov simulation model to determine the cost-effectiveness for performing an open or percutaneous intervention vs creating an AVF at a new anatomic location. This model compared strategies of creating a new AVF after the first to fourth reintervention within a 1-year time window, with the reference being creation of a new AVF on the fourth reintervention. Costs were measured from Medicare's perspective, and effectiveness was measured as quality-adjusted life-years (QALYs) and time in functional access. Incremental cost-effectiveness ratios (ICERs) were calculated by taking the ratio of the difference in cost and the difference in effectiveness between two strategies. RESULTS: A total of 720 AVFs that were created during the 8-year period reached maturity, and 407 (56%) underwent at least one intervention to maintain functional patency, with the median (interquartile range) time to first reintervention of 12.6 (10-17) months. For the strategies of creating a new AVF after the first versus the fourth reintervention, payer costs ranged from $3519 to $3922 for open procedures and $2134 to $3922 for percutaneous procedures. The ICERs for open interventions on failing AVFs were $357,143/QALY after the first reintervention and $95,876/QALY after the second reintervention. The ICERs for percutaneous interventions on failing AVFs ranged from $1,522,078/QALY after the first reintervention to $443,243/QALY after the third reintervention. CONCLUSIONS: Whereas the clinical effectiveness of performing percutaneous interventions on failing AVFs diminishes after each reintervention, they are nevertheless less costly than creating a new AVF. In comparison, our data show that creating a new AVF is cost-effective after the second open reintervention procedure.

Optimal medical management before lower extremity bypass for claudication in the veteran population.

OBJECTIVE: Optimizing medical management through glucose control, smoking cessation, and drug therapy (ie, antiplatelet and statin agents) is recommended as first-line therapy for patients with claudication. The aims of this study were to determine how frequently veterans with claudication received optimal medical management (OMM) before undergoing elective open lower extremity bypass procedures nationwide and whether preoperative OMM was associated with improved surgical outcomes. METHODS: We reviewed all patients within the Veterans Affairs (VA) Surgical Quality Improvement Program database who underwent elective open lower extremity bypass procedures for claudication at nationwide VA medical centers from 2005 until 2015. We defined OMM as a claudicant's having documentation of receiving all of the following within 12 months before surgery: prescriptions for antiplatelet, statin, and smoking cessation therapy (if a smoker) and monitoring of hemoglobin A1c (if diabetic). Outcome measures included occurrence of any 30-day VA Surgical Quality Improvement Program complication, amputation-free survival, and 30-day and 1-year mortality. We used multivariate regression and Cox proportional hazards models incorporating inverse probability treatment weighting to analyze the effect of OMM on outcome measures after adjusting for patient-level confounding. RESULTS: Among 10,271 lower extremity bypass procedures performed, 2265 (22%) were undertaken in claudicants with a median age of 63 years (interquartile range, 58-68 years). Of claudicants, 839 (37%) were diabetic, and 1333 (59%) patients smoked within 12 months before surgery. OMM was achieved in only 581 (26%) claudicants before they underwent surgery, although adherence to individual components was variable: antiplatelet, 55%; statin, 63%; smoking cessation, 58%; and hemoglobin A1c monitoring, 92%. In risk-adjusted analyses, there were no statistically significant differences in complication rates, amputation-free survival, or mortality outcomes among patients who received OMM compared with non-OMM patients. CONCLUSIONS: Only a quarter of veterans with claudication were documented as receiving OMM within the year before undergoing open lower extremity bypass across nationwide VA medical centers, highlighting the need for strategies to ensure that medical therapy is intensified before surgical revascularization. Nevertheless, our data showed that documentation of preoperative OMM did not lead to improved short- or long-term postoperative outcomes in these patients, suggesting that more objective measures of medical management are needed to ensure that peripheral arterial disease goals are achieved.

Prognostic implications of diagnosing frailty and sarcopenia in vascular surgery practice.

OBJECTIVE: Frailty and sarcopenia are related but independent conditions commonly diagnosed in older patients that can be used to assess their ability to tolerate the stress of major vascular surgery. For surgical decision-making, however, it is important to know the prognostic implications associated with each of these conditions. The study was designed to assess the association of frailty and sarcopenia phenotypes with long-term survival of patients undergoing surgical and nonsurgical management of vascular disease. METHODS: We retrospectively reviewed all patients presenting to the vascular surgery clinic at an academic hospital between December 2015 and August 2017 who underwent prospective frailty assessment with the Clinical Frailty Scale and who had abdominal computed tomography (CT) scans performed within the preceding 12 months. A single axial CT image at the caudal end of the third lumbar vertebra was assessed to measure cross-sectional areas of skeletal muscle. Sarcopenia was defined by established criteria specific for male and female patients. After patients were stratified by frailty and sarcopenia diagnoses along with comorbidities, the association with all-cause mortality was analyzed by Kaplan-Meier curves and Cox regression models. RESULTS: A total of 415 patients underwent both frailty and sarcopenia assessment, of whom 112 (27%) met sarcopenia criteria alone, 48 (12%) met only frailty criteria, and 56 (13%) met criteria for both phenotypes. There were 199 (48%) controls who met neither criterion. Vascular operations were performed in 167 (40%) patients after frailty and sarcopenia assessment, whereas 248 (60%) patients were managed nonoperatively with median (interquartile range) follow-up after CT imaging of 1.5 (1.1-2.2) years. Patients diagnosed with either phenotype were older (mean, 65 years vs 59 years; P < .001) and more likely to be male (69% vs 54%; P < .001) compared with patients without sarcopenia or frailty. Long-term survival was significantly decreased for patients diagnosed with either frailty alone or frailty and sarcopenia who underwent surgical or nonsurgical management (log-rank, P < .001 for both comparisons). In multivariate regression models, however, frailty was the only independent variable (hazard ratio, 7.7; 95% confidence interval, 3.2-18.7; P < .001) that predicted mortality. CONCLUSIONS: Frailty and sarcopenia overlap to varying degrees in patients presenting to vascular surgery clinics and can be used alone or in combination to predict long-term survival of older patients. However, our data indicate that it was only the diagnosis of frailty that was an independent predictor of mortality and had the strongest prognostic significance in patients undergoing both surgical and nonoperative management.

Comparative effectiveness of one-stage versus two-stage basilic vein transposition arteriovenous fistulas.

OBJECTIVE: Basilic vein transposition (BVT) fistulas may be performed as either a one-stage or two-stage operation, although there is debate as to which technique is superior. This study was designed to evaluate the comparative clinical efficacy and cost-effectiveness of one-stage vs two-stage BVT. METHODS: We identified all patients at a single large academic hospital who had undergone creation of either a one-stage or two-stage BVT between January 2007 and January 2015. Data evaluated included patient demographics, comorbidities, medication use, reasons for abandonment, and interventions performed to maintain patency. Costs were derived from the literature, and effectiveness was expressed in quality-adjusted life-years (QALYs). We analyzed primary and secondary functional patency outcomes as well as survival during follow-up between one-stage and two-stage BVT procedures using multivariate Cox proportional hazards models and Kaplan-Meier analysis with log-rank tests. The incremental cost-effectiveness ratio was used to determine cost savings. RESULTS: We identified 131 patients in whom 57 (44%) one-stage BVT and 74 (56%) two-stage BVT fistulas were created among 8 different vascular surgeons during the study period that each performed both procedures. There was no significant difference in the mean age, male gender, white race, diabetes, coronary disease, or medication profile among patients undergoing one- vs two-stage BVT. After fistula transposition, the median follow-up time was 8.3 months (interquartile range, 3-21 months). Primary patency rates of one-stage BVT were 56% at 12-month follow-up, whereas primary patency rates of two-stage BVT were 72% at 12-month follow-up. Patients undergoing two-stage BVT also had significantly higher rates of secondary functional patency at 12 months (57% for one-stage BVT vs 80% for two-stage BVT) and 24 months (44% for one-stage BVT vs 73% for two-stage BVT) of follow-up (P < .001 using log-rank test). However, there was no significant difference between groups in use of interventions (58% for one-stage BVT vs 51% for two-stage BVT; P = .5) to maintain patency. These findings were confirmed in multivariate analysis, in which two-stage BVTs were associated with a significantly lower rate of failure (hazard ratio, 0.39; 95% confidence interval, 0.2-0.8; P < .05) than one-stage BVTs after controlling for confounding variables. Finally, the two-stage BVT was more cost-effective (3.74 QALYs for two-stage BVT vs 3.32 QALYs for one-stage BVT) during 5 years, with an incremental cost-effectiveness ratio of $4681 per QALY. CONCLUSIONS: Our data show that two-stage BVTs are more durable and cost-effective than one-stage procedures, with significantly higher patency and lower rates of failure among comparable risk-stratified patients. These findings suggest that additional upfront costs and resources associated with creating two-stage BVTs are justified by their long-term outcomes.

Clinical effectiveness of open thrombectomy for thrombosed autogenous arteriovenous fistulas and grafts.

OBJECTIVE: Arteriovenous (AV) fistulas are the preferred hemodialysis access for patients with end-stage renal disease, although multiple interventions are typically needed to maintain patency. When AV fistulas thrombose, however, there is debate as to whether open thrombectomy should be attempted, particularly for salvage of upper arm fistulas. This study was designed to evaluate outcomes after open thrombectomy of upper arm and forearm AV fistulas compared with AV grafts. METHODS: We identified all patients who underwent an open thrombectomy procedure for a thrombosed AV fistula or graft at a single academic medical center between January 2006 and March 2017. The specific type of AV fistula or graft was evaluated, as were the patients' demographics, comorbidities, medications, adjunctive procedures during thrombectomy, and secondary interventions. The primary outcome measures, postintervention primary patency and postintervention secondary patency, were analyzed using Kaplan-Meier curves and Cox regression models for risk adjustment. RESULTS: During the study period, 209 open thrombectomy procedures were performed in 139 patients; 73 (35%) were undertaken in AV fistulas and 136 (65%) in grafts. Patients with upper arm fistulas (n = 52; 54% brachiocephalic, 46% brachiobasilic) and forearm fistulas (n = 16) were more likely to be male but less likely to have cerebrovascular disease or ischemic heart disease and to be receiving anticoagulation therapy compared with graft patients. After thrombectomy, the majority of patients underwent dialysis successfully (70% upper arm fistulas, 56% forearm fistulas, 63% grafts; P > .05), and 1-year survival rates were similar in all three cohorts. Postintervention primary patency at 1 year was significantly higher for AV fistulas vs grafts (33% for upper arm fistulas and 25% for forearm fistulas vs 9% for grafts; P < .05), which was confirmed in multivariate analysis, where upper arm AV fistulas had a 46% lower risk of recurrent thrombosis or secondary intervention (hazard ratio, 0.56; 95% confidence interval, 0.35-0.85; P < .05). Postintervention secondary patency at 1 year was similar between AV fistulas and grafts (44% for upper arm fistulas vs 43% for forearm fistulas vs 31% for grafts; P = .16), but in multivariate analysis, upper arm fistulas were significantly less likely to fail (hazard ratio, 0.63; 95% confidence interval, 0.40-1.00; P = .05). CONCLUSIONS: Our data suggest that AV fistula thrombectomy is successful in up to 70% of cases, with significantly improved risk-adjusted 1-year primary and secondary patency rates for upper arm fistulas compared with grafts. Whereas the risk of access failure is high after thrombectomy, efforts to salvage upper arm AV fistulas are effective in most patients and should be undertaken when feasible.

Preoperative frailty assessment predicts loss of independence after vascular surgery.

OBJECTIVE: Frailty, a clinical syndrome associated with loss of metabolic reserves, is prevalent among patients who present to vascular surgery clinics for evaluation. The Clinical Frailty Scale (CFS) is a rapid assessment method shown to be highly specific for identifying frail patients. In this study, we sought to evaluate whether the preoperative CFS score could be used to predict loss of independence after major vascular procedures. METHODS: We identified all patients living independently at home who were prospectively assessed using the CFS before undergoing an elective major vascular surgery procedure (admitted for >24 hours) at an academic medical center between December 2015 and December 2017. Patient- and procedure-level clinical data were obtained from our institutional Vascular Quality Initiative registry database. The composite outcome of discharge to a nonhome location or 30-day mortality was evaluated using bivariate and multivariate regression models. RESULTS: A total of 134 independent patients were assessed using the CFS before they underwent elective open abdominal aortic aneurysm repair (8%), endovascular aneurysm repair (26%), thoracic endovascular aortic repair (6%), suprainguinal bypass (6%), infrainguinal bypass (16%), carotid endarterectomy (19%), or peripheral vascular intervention (20%). Among 39 (29%) individuals categorized as being frail using the CFS, there was no significant difference in age or American Society of Anesthesiologists physical status compared with nonfrail patients. However, frail patients were significantly more likely to need mobility assistance after surgery (62% frail vs 22% nonfrail; P < .01) and to be discharged to a nonhome location (22% frail vs 6% nonfrail; P = .01) or to die within 30 days after surgery (8% frail vs 0% nonfrail; P < .01). Preoperative frailty was associated with a >12-fold higher risk (odds ratio, 12.1; 95% confidence interval, 2.17-66.96; P < .01) of 30-day mortality or loss of independence, independent of the vascular procedure undertaken. CONCLUSIONS: The CFS is a practical tool for assessing preoperative frailty among patients undergoing elective major vascular surgery and can be used to predict likelihood of requiring discharge to a nursing facility or death after surgery. The identification of frail patients before major surgery can help manage postoperative expectations and optimize transitions of care.

Clots Are Potent Triggers of Inflammatory Cell Gene Expression: Indications for Timely Fibrinolysis.

OBJECTIVE: Blood vessel wall damage often results in the formation of a fibrin clot that traps inflammatory cells, including monocytes. The effect of clot formation and subsequent lysis on the expression of monocyte-derived genes involved in the development and progression of ischemic stroke and other vascular diseases, however, is unknown. Determine whether clot formation and lysis regulates the expression of human monocyte-derived genes that modulate vascular diseases. APPROACH AND RESULTS: We performed next-generation RNA sequencing on monocytes extracted from whole blood clots and using a purified plasma clot system. Numerous mRNAs were differentially expressed by monocytes embedded in clots compared with unclotted controls, and IL-8 (interleukin 8) and MCP-1 (monocyte chemoattractant protein-1) were among the upregulated transcripts in both models. Clotted plasma also increased expression of IL-8 and MCP-1, which far exceeded responses observed in lipopolysaccharide-stimulated monocytes. Upregulation of IL-8 and MCP-1 occurred in a thrombin-independent but fibrin-dependent manner. Fibrinolysis initiated shortly after plasma clot formation (ie, 1-2 hours) reduced the synthesis of IL-8 and MCP-1, whereas delayed fibrinolysis was far less effective. Consistent with these in vitro models, monocytes embedded in unresolved thrombi from patients undergoing thrombectomy stained positively for IL-8 and MCP-1. CONCLUSIONS: These findings demonstrate that clots are potent inducers of monocyte gene expression and that timely fibrinolysis attenuates inflammatory responses, specifically IL-8 and MCP-1. Dampening of inflammatory gene expression by timely clot lysis may contribute to the clinically proven efficacy of fibrinolytic drug treatment within hours of stroke onset.

Rapid Methods for Routine Frailty Assessment during Vascular Surgery Clinic Visits.

BACKGROUND: Frailty assessment can help vascular surgeons predict perioperative risk and long-term mortality for their patients. Unfortunately, comprehensive frailty assessments take too long to integrate into clinic workflow. This study was designed to evaluate 2 rapid methods for assessing frailty during vascular clinics-a short patient-reported survey and a provider-reported frailty scale. METHODS: We prospectively enrolled 159 patients presenting to an academic medical center vascular surgery clinic between May and November 2016. Patients underwent frailty assessment using 2 rapid methods: (1) the Frail Nondisabled (FiND) survey (5 questions) and (2) the Clinical Frailty Scale (CFS; 9-point scale from robust to severely frail). These were followed by administering the Fried Index, a validated frailty assessment method with 5 measures (weight loss, exhaustion, grip strength, walking speed, and activity level). The correlation between Fried scores (reference standard) with frailty diagnoses derived from FiND and CFS was analyzed using the Spearman-rank test, Cohen's kappa, sensitivity/specificity tests, and receiver operating curves. RESULTS: The evaluated cohort included 87 (55%) females, a mean age of 61 years, 126 (79%) preoperative patients, and 32 (20%) categorized as frail using the Fried Index criteria. The FiND survey was very sensitive (91%) but less specific for diagnosing frailty. In comparison, the CFS was highly specific (96%) for diagnosing frailty and exhibited high inter-rater reliability between surgeon and medical assistant scores (kappa: 0.79; 95% CI: 0.72-0.87; P < 0.001). There was moderate correlation between frailty assigned using the Fried Index and the CFS (rho: 0.41-0.44). CONCLUSIONS: Frailty can be quickly and effectively assessed during vascular surgery clinic using a combination of patient-reported (FiND) and provider-reported (CFS) methods to improve diagnostic accuracy. Implementing routine frailty assessment into clinic workflow can be a valuable tool for risk prediction and surgical decision-making.

Western Vascular Society guidelines for transfer of patients with ruptured abdominal aortic aneurysm.

INTRODUCTION: When a patient with ruptured abdominal aortic aneurysm (rAAA) presents at a facility ill-equipped to provide care, transfer may provide the best chance for survival. Large distances and long travel times provide challenging barriers to prompt and appropriate care in the western United States. METHODS: The Western Vascular Society (WVS) adopted a set of guidelines in considering transfer of a patient with an rAAA using published literature, membership survey and input, and existing recommendations. This article reports the guidelines and describes the process and rationale behind their development. RESULTS: Fifteen guidelines for transfer and care of rAAAs were endorsed by the WVS. CONCLUSIONS: When local care cannot be provided, transfer guidelines may standardize care for rAAAs and may be applicable across may practice settings.