Participation in the Vascular Quality Initiative is associated with improved perioperative medication use, which is associated with longer patient survival

Appropriateness of Care Measures: A Novel Approach to Quality

The clinical judgment of a physician is one of the most important aspects of medical quality, yet it is rarely captured with quality measures in use today. We propose a novel approach using individualized physician benchmarking that measures the appropriateness of care that a physician delivers by looking at their practice pattern in a specific clinical situation. A prime application of our novel approach to appropriateness measures is the surgical management of peripheral artery disease and claudication. We discuss 4 potential consensus metrics for the treatment of claudication that explore appropriateness of care of claudication management and are meaningful, actionable, and quantifiable. Given the multitude of medical specialties involved in the care of patients with peripheral artery disease and the consequences of both preemptive and delayed care, it is in all of our interests to promote data transparency with confidential communications to outlier physicians while advocating for evidence-based management.

Earned outcomes correlate with reliability-adjusted surgical mortality after abdominal aortic aneurysm repair and predict future performance

OBJECTIVE

Cumulative, probability-based metrics are regularly used to measure quality in professional sports, but these methods have not been applied to health care delivery. These techniques have the potential to be particularly useful in describing surgical quality, where case volume is variable and outcomes tend to be dominated by statistical "noise." The established statistical technique used to adjust for differences in case volume is reliability-adjustment, which emphasizes statistical "signal" but has several limitations. We sought to validate a novel measure of surgical quality based on earned outcomes methods (deaths above average [DAA]) against reliability-adjusted mortality rates, using abdominal aortic aneurysm (AAA) repair outcomes to illustrate the measure's performance.

METHODS

Earned outcomes methods were used to calculate the outcome of interest for each patient: DAA. Hospital-level DAA was calculated for non-ruptured open AAA repair and endovascular aortic repair (EVAR) in the Vascular Quality Initiative database from 2016 to 2019. DAA for each center is the sum of observed - predicted risk of death for each patient; predicted risk of death was calculated using established multivariable logistic regression modeling. Correlations of DAA with reliability-adjusted mortality rates and procedure volume were determined. Because an accurate quality metric should correlate with future results, outcomes from 2016 to 2017 were used to categorize hospital quality based on: (1) risk-adjusted mortality; (2) risk- and reliability-adjusted mortality; and (3) DAA. The best performing quality metric was determined by comparing the ability of these categories to predict 2018 to 2019 risk-adjusted outcomes.

RESULTS

During the study period, 3734 patients underwent open repair (106 hospitals), and 20,680 patients underwent EVAR (183 hospitals). DAA was closely correlated with reliability-adjusted mortality rates for open repair (r = 0.94; P < .001) and EVAR (r = 0.99; P < .001). DAA also correlated with hospital case volume for open repair (r = -.54; P < .001), but not EVAR (r = 0.07; P = .3). In 2016 to 2017, most hospitals had 0% mortality (55% open repair, 57% EVAR), making it impossible to evaluate these hospitals using traditional risk-adjusted mortality rates alone. Further, zero mortality hospitals in 2016 to 2017 did not demonstrate improved outcomes in 2018 to 2019 for open repair (3.8% vs 4.6%; P = .5) or EVAR (0.8% vs 1.0%; P = .2) compared with all other hospitals. In contrast to traditional risk-adjustment, 2016 to 2017 DAA evenly divided centers into quality quartiles that predicted 2018 to 2019 performance with increased mortality rate associated with each decrement in quality quartile (Q1, 3.2%; Q2, 4.0%; Q3, 5.1%; Q4, 6.0%). There was a significantly higher risk of mortality at worst quartile open repair hospitals compared with best quartile hospitals (odds ratio, 2.01; 95% confidence interval, 1.07-3.76; P = .03). Using 2016 to 2019 DAA to define quality, highest quality quartile open repair hospitals had lower median DAA compared with lowest quality quartile hospitals (-1.18 DAA vs +1.32 DAA; P < .001), correlating with lower median reliability-adjusted mortality rates (3.6% vs 5.1%; P < .001).

CONCLUSIONS

Adjustment for differences in hospital volume is essential when measuring hospital-level outcomes. Earned outcomes accurately categorize hospital quality and correlate with reliability-adjustment but are easier to calculate and interpret. From 2016 to 2019, highest quality open AAA repair hospitals prevented >40 perioperative deaths compared with the average hospital, and >80 perioperative deaths compared with lowest quality hospitals.

Barriers to Antiplatelet and Statin Adherence Following Major Vascular Intervention

BACKGROUND

Antiplatelets and statins therapies are associated with improved cardiovascular outcomes following major vascular intervention. Many vascular surgery institutions are reporting improved prescribing rates for aspirin (ASA), P2Y12 antagonists, and statins. Nevertheless, there remains limited publication describing rates and patient-perceived barriers for postoperative adherence. The purpose of this study is to investigate patient nonadherence to antiplatelet and statin therapies following major vascular intervention.

METHODS

A retrospective review of patients who underwent major vascular intervention at a single academic center was performed. The prescribing rates of ASA, P2Y12 antagonists, and statins were reviewed. Postoperative adherence, defined as consistent intake as prescribed, was evaluated at 1, 3, 6, 9, and 12 months using electronic documentation of both follow-up clinic appointments and phone call assessments, then corroborated with pharmacy fulfilment records. Patient-reported barriers to medication adherence were also examined.

RESULTS

A total of 101 subjects underwent major vascular intervention between January 2020 and July 2020, 98% of whom were discharged on at least 1 antiplatelet or statin agent. Approximately 90% of patients were discharged with ASA, 32% with a P2Y12 antagonist, and 96% with a statin. All patients who maintained adherence up to 6 months continued to report adherence at 9 and 12 months. Consistent adherence at 12 months was documented in 76% of patients on ASA, 81% on P2Y12 antagonism therapy, and 73% on statins. New adverse drug reactions represented the most common barrier to achieving adherence (37% [n = 20]). Preoperative therapy with ASA, P2Y12 antagonists, and statins were all independently predictive of postoperative adherence to the same regimen (P ≤ 0.001). The female gender was also associated with higher rates of adherence to postoperative P2Y12 antagonism therapy (P ≤ 0.05).

CONCLUSIONS

The current prescribing rates for antiplatelet and statin agents are promising, but postoperative nonadherence remains a multifaceted issue.

Variability in guideline-directed medical therapy across sites and operators and long-term mortality and amputation outcomes risk in patients undergoing peripheral vascular interventions

BACKGROUND

The use of guideline-directed medical therapy (GDMT) in patients undergoing peripheral vascular interventions (PVIs) decreases the risk of death and amputation and may decrease hospital readmissions. The variability of GDMT prescription across sites and operators and the proportionality of risk is not well understood. We aimed to study the association between variability of GDMT prescription at the site and operator level and outcomes (including 90-day readmissions and 24-month all-cause mortality and major amputation).

METHODS

We examined GDMT discharge rates in PVIs performed between 2017 and 2018 using Medicare-linked Vascular Quality Initiative registry. GDMT included a statin, antiplatelet therapy, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-i/ARB) if hypertensive. Quartiles (Q1-4) of GDMT rates were documented by operators and sites and variability was quantified using median odds ratios (MOR) and intraclass correlation (ICC). The association between lower GDMT rates (per 10%) by sites and operators with 90-day readmission were calculated using logistic regression, and with 24-month mortality and major amputation using parametric survival model. Models were adjusted for patient-level factors and included sites and operators nested within sites as 2 random effects.

RESULTS

GDMT rates for 17,147 patients across 223 sites and 1,263 operators ranged from 0% to 38% (Q1, MOR 1.43, 95%CI 1.39-1.47, P ≤ .001) to 57%-100% (Q4, MOR 1.48, 95%CI 1.44-1.51, P ≤ .001). Four percent of variance in GDMT use was explained by sites (ICC 3.9, 95%CI 2.9-5.3) and operators (ICC 4.1, 95%CI 3.1-5.4). A dose-response relationship was noted between lower GDMT rates and increased risk of 90-day readmission risk by sites (P = .021) and operators (P < .001). Lower GDMT prescription by site was associated with higher risk of 24-month mortality (HR = 1.07, 95%CI 1.02-1.13) and major amputation (HR = 1.08, 95%CI 1.01-1.15). Similar associations were found for GDMT use by provider (mortality HR = 1.05, 95%CI 1.02-1.08 and amputation HR = 1.04, 95%CI 1.00-1.08).

CONCLUSION

Both at the operator and health system level, there was significant variability in GDMT prescription following PVI, proportionally translating into risk for readmission, mortality, and major amputation. Targeted quality efforts should prioritize both operator and site levels to improve GDMT use and outcomes for patients undergoing PVI.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Automatic 1-year follow-up appointment creation and reminders can improve long-term follow-up after carotid revascularization

BACKGROUND

Long-term follow-up (LTFU) following carotid revascularization is important for post-surgical care, stroke risk optimization and post-market surveillance of new technologies.

METHODS

We instituted a quality improvement project to improve LTFU rates for carotid revascularizations (primary outcome) by scheduling perioperative and one-year follow-up appointments at time of surgery discharge. A temporal trends analysis (Q1 2019 through Q1 2022), multivariable regression, and interrupted time series (ITS) were performed to compare pre-post intervention LTFU rates.

RESULTS

269 consecutive patients were included (151 pre-intervention, 118 post-intervention; mean 71 ​± ​12 years-old, 39% female, 77% White). The overall LTFU rate improved (64.9%-78.8%; P ​= ​0.013) after the intervention. After controlling for patient factors, procedures performed after the intervention were associated with increased odds of being seen for 1-year follow-up (OR: 2.2 95%CI: 1.2-4.0). Quarterly ITS analysis corroborated this relationship (P ​= ​0.01).

CONCLUSIONS

Time-of-surgery appointment creation and automated patient reminders can improve LTFU rates following carotid revascularizations.

Using machine learning to predict outcomes following carotid endarterectomy

OBJECTIVE

Prediction of outcomes following carotid endarterectomy (CEA) remains challenging, with a lack of standardized tools to guide perioperative management. We used machine learning (ML) to develop automated algorithms that predict outcomes following CEA.

METHODS

The Vascular Quality Initiative (VQI) database was used to identify patients who underwent CEA between 2003 and 2022. We identified 71 potential predictor variables (features) from the index hospitalization (43 preoperative [demographic/clinical], 21 intraoperative [procedural], and 7 postoperative [in-hospital complications]). The primary outcome was stroke or death at 1 year following CEA. Our data were split into training (70%) and test (30%) sets. Using 10-fold cross-validation, we trained six ML models using preoperative features (Extreme Gradient Boosting [XGBoost], random forest, Naïve Bayes classifier, support vector machine, artificial neural network, and logistic regression). The primary model evaluation metric was area under the receiver operating characteristic curve (AUROC). After selecting the best performing algorithm, additional models were built using intra- and postoperative data. Model robustness was evaluated using calibration plots and Brier scores. Performance was assessed on subgroups based on age, sex, race, ethnicity, insurance status, symptom status, and urgency of surgery.

RESULTS

Overall, 166,369 patients underwent CEA during the study period. In total, 7749 patients (4.7%) had the primary outcome of stroke or death at 1 year. Patients with an outcome were older with more comorbidities, had poorer functional status, and demonstrated higher risk anatomic features. They were also more likely to undergo intraoperative surgical re-exploration and have in-hospital complications. Our best performing prediction model at the preoperative stage was XGBoost, achieving an AUROC of 0.90 (95% confidence interval [CI], 0.89-0.91). In comparison, logistic regression had an AUROC of 0.65 (95% CI, 0.63-0.67), and existing tools in the literature demonstrate AUROCs ranging from 0.58 to 0.74. Our XGBoost models maintained excellent performance at the intra- and postoperative stages, with AUROCs of 0.90 (95% CI, 0.89-0.91) and 0.94 (95% CI, 0.93-0.95), respectively. Calibration plots showed good agreement between predicted and observed event probabilities with Brier scores of 0.15 (preoperative), 0.14 (intraoperative), and 0.11 (postoperative). Of the top 10 predictors, eight were preoperative features, including comorbidities, functional status, and previous procedures. Model performance remained robust on all subgroup analyses.

CONCLUSIONS

We developed ML models that accurately predict outcomes following CEA. Our algorithms perform better than logistic regression and existing tools, and therefore, have potential for important utility in guiding perioperative risk mitigation strategies to prevent adverse outcomes.

Discharge prescription patterns for antiplatelet and statin therapy following carotid endarterectomy: an analysis of the vascular quality initiative

OBJECTIVES

Despite guidelines endorsing statin and single antiplatelet therapy (SAPT) therapy post-carotid endarterectomy (CEA), these medications may be either under or inappropriately prescribed. We determined rates of new statin prescriptions as well as change in antiplatelet therapy (APT) regimen at discharge. We identified characteristics associated with these occurrences.

DESIGN

We performed a retrospective Vascular Quality Initiative registry analysis of more than 125 000 patients who underwent CEA from 2013 to 2021.

SETTING

The Vascular Quality Initiative is a multicentre registry database including academic and community-based hospitals throughout the USA.

PARTICIPANTS

Patients age≥18 years undergoing CEA with available statin and APT data (preprocedure and postprocedure) were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

We determined overall rates of statin and APT prescription at discharge. Multivariate logistic regression was used to determine clinical and demographic characteristics that were mostly associated with new statin prescription or changes in APT regimen at discharge.

RESULTS

Study participants were predominantly male (61%) and White (90%), with a mean age of 70.6±9.1. 13.1% of participants were not on statin therapy pre-CEA, and 48% of these individuals were newly prescribed one. Statin rates steadily increased throughout the study period: 36.2% in 2013 to 62% in 2021. A higher likelihood of new statin prescription was associated with non-race, diabetes, coronary heart disease, stroke, TIA and a non-elective indication. Older age, female gender, chronic obstructive pulmonary disease and prior carotid revascularisation were associated with a lower likelihood of new statin prescription. Nearly all participants were discharged on APT (63% SAPT and 37% dual antiplatelet therapy, DAPT). Among these individuals, 16% were discharged on a regimen that was different from the one on admission (11 947 (10.7%) of patients were upgraded to DAPT and 5813 (5.2%) were downgraded to SAPT).

CONCLUSIONS

Although statin use has substantially improved following CEA, more than half of individuals not on a statin preprocedure remained this way at discharge. In addition, DAPT at discharge was frequent, a quarter of whom were on SAPT preprocedure. Further efforts are needed to improve rates of new statin prescriptions, ensure appropriate APT intensity at discharge and determine how different discharge APT regimens impact outcomes.

Vascular Quality Initiative assessment of compliance with Society for Vascular Surgery clinical practice guidelines on the management of extracranial cerebrovascular disease

OBJECTIVES

Compliance with Society for Vascular Surgery (SVS) clinical practice guidelines (CPGs) is associated with improved outcomes for the treatment of abdominal aortic aneurysm, but this has not been assessed for carotid artery disease. The Vascular Quality Initiative (VQI) registry was used to examine compliance with the SVS CPGs for the management of extracranial cerebrovascular disease and its impact on outcomes.

METHODS

The 2021 SVS extracranial cerebrovascular disease CPGs were reviewed for evaluation by VQI data. Compliance rates by the center and provider were calculated, and the impact of compliance on outcomes was assessed using logistic regression with inverse probability-weighted risk adjustment for each CPG recommendation, allowing for clustering by the center. Our primary outcome was a composite end point of in-hospital stroke/death. As a secondary analysis, compliance with the 2021 SVS carotid implementation document recommendations and associated outcomes were also assessed.

RESULTS

Of the 11 carotid CPG recommendations, 4 (36%) could be evaluated using VQI registry data. Median center-specific CPG compliance ranged from 38% to 95%, and median provider-specific compliance ranged from 36% to 100%. After adjustment, compliance with 2 of the recommendations was associated with lower rates of in-hospital stroke/death: first, the use of best medical therapy (antiplatelet and statin therapy) in low/standard surgical risk patients undergoing carotid endarterectomy for >70% asymptomatic stenosis (event rate in compliant vs noncompliant cases 0.59% vs 1.3%; adjusted odds ratio: 0.44, 95% confidence interval: 0.29-0.66); and second, carotid endarterectomy over transfemoral carotid artery stenting in low/standard surgical risk patients with >50% symptomatic stenosis (1.9% vs 3.4%; adjusted odds ratio: 0.55, 95% confidence interval: 0.43-0.71). Of the 132 implementation document recommendations, only 10 (7.6%) could be assessed using VQI data, with median center- and provider-specific compliance rates ranging from 67% to 100%. The impact of compliance on outcomes could only be assessed for 6 (4.5%) of these recommendations, and compliance with all 6 recommendations was associated with lower stroke/death.

CONCLUSIONS

Few SVS recommendations could be assessed in the VQI because of incongruity between the recommendations and the VQI data variables collected. Although guideline compliance was extremely variable among VQI centers and providers, compliance with most of these recommendations was associated with improved outcomes after carotid revascularization. This finding confirms the value of guideline compliance, which should be encouraged for centers and providers. Optimization of VQI data to promote evaluation of guideline compliance and distribution of these findings to VQI centers and providers will help facilitate quality improvement efforts in the care of vascular patients.

Optimising Medications in Older Vascular Surgery Patients Through Geriatric Co-management

BACKGROUND

Prescribing of potentially inappropriate medications and under-prescribing of guideline-recommended medications for cardiovascular risk modification have both been associated with negative outcomes in older adults. Hospitalisation represents an important opportunity to optimise medication use and may be achieved through geriatrician-led interventions.

OBJECTIVE

We aimed to evaluate whether implementation of a novel model of care called Geriatric Comanagement of older Vascular (GeriCO-V) surgery patients is associated with improvements in medication prescribing.

METHODS

We used a prospective pre-post study design. The intervention was a geriatric co-management model, where a geriatrician delivered comprehensive geriatric assessment-based interventions including a routine medication review. We included consecutively admitted patients to the vascular surgery unit at a tertiary academic centre aged ≥ 65 years with an expected length of stay of ≥ 2 days and who were discharged from hospital. Outcomes of interest were the prevalence of at least one potentially inappropriate medication as defined by the Beers Criteria at admission and discharge, and rates of cessation of at least one potentially inappropriate medication present on admission. In the subgroup of patients with peripheral arterial disease, the prevalence of guideline-recommended medications on discharge was determined.

RESULTS

There were 137 patients in the pre-intervention group (median [interquartile range] age: 80.0 [74.0-85.0] years, 83 [60.6%] with peripheral arterial disease) and 132 patients in the post-intervention group (median [interquartile range] age: 79.0 (73.0-84.0) years, 75 [56.8%] with peripheral arterial disease). There was no change in the prevalence of potentially inappropriate medication use from admission to discharge in either group (pre-intervention: 74.5% on admission vs 75.2% on discharge; post-intervention: 72.0% vs 72.7%, p = 0.65). Forty-five percent of pre-intervention group patients had at least one potentially inappropriate medication present on admission ceased, compared with 36% of post-intervention group patients (p = 0.11). A higher number of patients with peripheral arterial disease in the post-intervention group were discharged on antiplatelet agent therapy (63 [84.0%] vs 53 [63.9%], p = 0.004) and lipid-lowering therapy (58 [77.3%] vs 55 [66.3%], p = 0.12).

CONCLUSIONS

Geriatric co-management was associated with an improvement in guideline-recommended antiplatelet agent prescribing aimed at cardiovascular risk modification for older vascular surgery patients. The prevalence of potentially inappropriate medications was high in this population, and was not reduced with geriatric co-management.

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.

Impact of Guideline-Directed Medical Therapy on 10-Year Mortality after Revascularization for Patients with Chronic Limb-Threatening Ischemia

AIMS

This study aimed to investigate the long-term impact of guideline-directed medical therapy (GDMT) on 10-year mortality in patients with chronic limb-threatening ischaemia (CLTI) after revascularization.

METHODS

We performed a retrospective multicentre study enrolle 459 patients with CLTI who underwent revascularization (396 endovascular therapy [EVT] and 63 bypass surgery [BSX] cases) between January 2007 and December 2011. The primary outcome measure was all-cause mortality. We additionally explored the predictors for all-cause mortality using Cox regression hazard models; the influence of GDMT, defined as prescription of antiplatelet agents, statins, and angiotensin converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) in aggregate, on all-cause mortality, and the association between baseline characteristics using interaction effects.

RESULTS

During the 10-year follow-up after revascularization, 234 patients died. In Kaplan-Meier analysis, 10-year mortality was significantly lower in patients who received statins (p＜.001) and ACE inhibitors or ARBs (p=.010) than those who did not. However, there were no differences in 10-year mortality between patients who received anti-platelet agents and those who did not (p=.62). Interaction analysis revealed that GDMT had a significantly different hazard ratio in patients who were and were not on hemodialysis and in those treated with EVT or BSX (p for interaction =.002 and .044, respectively). In the multivariate analysis, age ＞75 years, non-ambulatory status, hemodialysis, congestive heart failure, left ventricular ejection fraction ＜50%, and GDMT were significantly associated with all-cause mortality.

CONCLUSIONS

Appropriate GDMT use was independently associated with 10-year mortality in patients with CLTI after revascularization.

Outcomes of Axillofemoral Bypass for Intermittent Claudication

OBJECTIVE

While endovascular therapy is often first-line treatment for medically refractory intermittent claudication (IC) caused by aorto-femoral disease, suprainguinal bypass is commonly performed. Although this is often aorto-femoral bypass (AoFB), axillo-femoral bypass (AxFB) is still sometimes performed despite limited data evaluating its utility in the management of IC. Our goal was to assess the safety and durability of AxFB performed for IC.

METHODS

The Vascular Quality Initiative (2009-2019) was queried for suprainguinal bypass performed for IC. Univariable and multivariable analyses were used to compare perioperative and one-year outcomes between AxFB and a comparison cohort of AoFB.

RESULTS

We identified 3,261 suprainguinal bypasses performed for IC: 436 AxFB and 2,825 AoFB. Overall, mean age was 61.4 ± 9.1 years, 58.8% of patients were male sex, and 59.7% currently smoked. Patients undergoing AxFB, compared with AoFB, were more often older, male, never-smokers, and ambulated with assistance (all P<.001). They more often had hypertension, diabetes, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, end-stage renal disease, previous outflow peripheral endovascular interventions, and previous inflow or outflow bypass. AxFB, compared with AoFB, were more often uni-femoral (all P<.05). Patients undergoing AxFB, compared with AoFB, had shorter postoperative length of stay (median 4 vs. 6 days) and fewer perioperative pulmonary (3% vs. 7.9%) and renal complications (5.5% vs. 9.9%), but more perioperative ipsilateral major amputations (.9% vs. 0.04%) (all P<.05). There were no significant differences in perioperative myocardial infarction (2.8% vs. 2.7%), stroke (.7% vs. 1.1%), and death (1.8% vs. 1.7%) rates, respectively. At one year, Kaplan-Meier analysis demonstrated that the AxFB, compared with AoFB cohort, exhibited higher rates of death (7.3% vs. 3.6%, P=.002); graft occlusion or death (14.3% vs. 7.2%, P=.001); ipsilateral major amputation or death (12.5% vs. 5.6%, P<.001); and reintervention, amputation, or death (19% vs. 8.6%, P<.001). On multivariable analysis, AxFB was independently associated with increased risk of one-year reintervention, amputation, or death (HR 1.6, 95% CI 1.03-2.4, P=.04).

CONCLUSIONS

This retrospective analysis suggests that long-term complications were more frequent in patients who underwent AxFB as compared to AoFB, although patients treated with AxFB were at higher risk with more comorbidities. Since AxFB is associated with significant perioperative morbidity, mortality, and long-term complications, serious consideration should be given prior to its use for IC.

Prescribing of Statins After Lower Extremity Revascularization Procedures in the US

IMPORTANCE

The use of statins in patients with symptomatic peripheral artery disease remains suboptimal despite strong clinical practice guideline recommendations; however, it is unknown whether rates are associated with substantial improvements after lower extremity revascularization.

OBJECTIVE

To report longitudinal trends of statin use in patients with peripheral artery disease undergoing lower extremity revascularization and to identify the clinical and procedural characteristics associated with prescriptions for new statin therapy at discharge.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective cross-sectional study using data from the Vascular Quality Initiative registry of patients who underwent lower extremity peripheral artery disease revascularization from January 1, 2014, through December 31, 2019. The Vascular Quality Initiative is a multicenter registry database including academic and community-based hospitals throughout the US. Patients aged 18 years or older undergoing lower extremity revascularization with available statin data (preprocedure and postprocedure) were included. Those not receiving statin therapy for medical reasons were excluded from final analyses.

EXPOSURES

Patients undergoing lower extremity revascularization for whom statin therapy is indicated.

MAIN OUTCOMES AND MEASURES

Multivariate logistic regression was used to determine the clinical and procedural characteristics associated with new statin prescription for patients not already taking a statin preprocedure. The overall rates of statin prescription as well as rates of new statin prescription at discharge were determined. In addition, the clinical, demographic, and procedural characteristics associated with new statin prescription were analyzed.

RESULTS

There were 172 025 procedures corresponding to 125 791 patients (mean [SD] age, 67.7 [11.0] years; 107 800 men [62.7%]; and 135 405 White [78.7%]) included in the analysis. Overall rates of statin prescription at discharge improved from 17 299 of 23 093 (75%) in 2014 to 29 804 of 34 231 (87%) in 2019. However, only 12 790 of 42 020 patients (30%) not already taking a statin at the time of revascularization during the study period were newly discharged with a statin medication. New statin prescription rates were substantially lower after endovascular intervention (7745 of 29 581 [26%]) than after lower extremity bypass (5045 of 12 439 [41%]). Body mass index of 30 or greater (odds ratio [OR], 1.13; 95% CI, 1.04-1.24; P < .001), diabetes (diet-controlled vs no diabetes, OR, 1.22; 95% CI, 1.05-1.41; P = .01), smoking (current vs never, OR, 1.32; 95% CI, 1.21-1.45; P < .001), hypertension (OR, 1.19; 95% CI, 1.09-1.29; P < .001), and coronary heart disease (OR, 1.26; 95% CI, 1.17-1.35; P < .001) were associated with an increased likelihood of new statin prescription after endovascular intervention, whereas female sex, older age, antiplatelet use, and prior peripheral revascularization were associated with a decreased likelihood.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, although statin use was associated with a substantial improvement after lower extremity revascularization, more than two-thirds of patients not already taking a statin preprocedure remained not taking a statin at discharge. Further investigations to understand the clinical implications of these findings and develop clinician- and system-based interventions are needed.

A statewide quality improvement collaborative significantly improves quality metric adherence and physician engagement in vascular surgery

BACKGROUND

Quality improvement national registries provide structured, clinically relevant outcome and process-of-care data to practitioners-with regional meetings to disseminate best practices. However, whether a quality improvement collaborative affects processes of care is less clear. We examined the effects of a statewide hospital collaborative on the adherence rates to best practice guidelines in vascular surgery.

METHODS

A large statewide retrospective quality improvement database was reviewed for 2013 to 2019. Hospitals participating in the quality improvement collaborative were required to submit adherence and outcomes data and meet semiannually. They received an incentive through a pay for participation model. The aggregate adherence rates among all hospitals were calculated and compared.

RESULTS

A total of 39 hospitals participated in the collaborative, with attendance of surgeon champions at face-to-face meetings of >85%. Statewide, the hospital systems improved every year of participation in the collaborative across most "best practice" domains, including adherence to preoperative skin preparation recommendations (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.76-1.79; P < .001), intraoperative antibiotic redosing (OR, 1.09; 95% CI, 1.02-1.17; P = .018), statin use at discharge for appropriate patients (OR, 1.18; 95% CI, 1.16-1.2; P < .001), and reducing transfusions for asymptomatic patients with hemoglobin >8 mg/dL (OR, 0.66; 95% CI, 0.66-0.66; P < .001). The use of antiplatelet therapy at discharge remained high and did not change significantly during the study period. Teaching hospital and urban or rural status did not affect adherence. The adherence rates exceeded the professional society mean rates for guideline adherence.

CONCLUSIONS

The use of a statewide hospital collaborative with incentivized semiannual meetings resulted in significant improvements in adherence to "best practice" guidelines across a large, heterogeneous group of hospitals.

Predictors of Underutilization of Medical Therapy in Patients Undergoing Endovascular Revascularization for Peripheral Artery Disease

OBJECTIVES

The aim of this study was to explore discharge prescription rates of guideline-directed medical therapy (GDMT), defined as aggregate antiplatelet agent, statin, and ACE inhibitor or angiotensin receptor blocker use after endovascular lower extremity (LE) peripheral vascular intervention.

BACKGROUND

Little is known about contemporary GDMT prescription following LE PVI.

METHODS

Sex, age, and comorbid conditions were related to discharge GDMT prescription among patients undergoing LE PVI for symptomatic peripheral artery disease in the 2014-2018 Vascular Study Group of New England Vascular Quality Initiative. Multivariate logistic regression was used to identify independent predictors of discharge GDMT prescription.

RESULTS

Among 12,316 patients, only 47.4% (n = 5,844) were discharged on GDMT after LE PVI. Most patients were discharged on antiplatelet agents (95.2%), with statins (83.5%) and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (55.8%) prescribed less often. A higher proportion of patients were on Class 1 guideline-recommended therapy with antiplatelet agents and statins (80.5%). In multivariate analysis, female sex, older age, end-stage renal disease, chronic limb-threatening ischemia, and congestive heart failure were negative predictors of discharge GDMT prescription, while hypertension, diabetes, coronary artery disease, and prior LE PVI or bypass were positive predictors.

CONCLUSIONS

Fewer than one-half of patients undergoing LE PVI are discharged on appropriate GDMT. As expected, traditional atherosclerotic risk factors and measures of greater atherosclerotic disease burden were associated with a greater likelihood of GDMT prescription. However, women and patients with the highest risk for atherothrombosis and limb loss were least likely to be prescribed these agents. Provider- and patient-directed educational efforts are needed to close these treatment gaps.

Precision Medicine Enables More TNM-Like Staging in Patients With Chronic Limb Threatening Ischemia

Introduction: In cancer, there are survival-based staging systems and tailored, stage-based treatments. There is little personalized treatment in vascular disease. The 2019 Global Vascular Guidelines on the Management of CLTI proposed successful treatment hinges upon Patient risk, Limb severity, and ANatomic complexity (PLAN). We sought to confirm a three axis approach and define how increasing severity affects mortality, not just limb loss.

Methods: Patients revascularized for incident CLTI at our institution from 2013 to 2017 were included. Outcomes were mortality, limb loss, the composite endpoint of amputation-free survival. Using Bayesian machine learning, specifically supervised topic modeling, clusters of patient features associated with mortality were formed after controlling for revascularization type. Patients were assigned to the cluster they belonged to with highest probability; clusters were characterized by analyzing the characteristics of patients within them. Patient outcomes were used to order the clusters into stages with increasing mortality.

Results: We defined three distinct clusters as the basis for patient- and limb-centered stages. Across stages, rates of 1-year mortality were 7.6, 13.8, 18.9% and rates of amputation-free survival were 84.8, 79.3, and 63.2%. Stage one had patients with rest pain and previous revascularization who were less likely to have wounds, diabetes, and renal disease. Stage two had doubled mortality, likely related to diabetes prevalence. Stage three is characterized by high rates of complicated comorbidities, particularly end stage renal disease, and significantly higher rate of limb loss (22.6 vs. 8% in stages one and two).

Conclusion: Using precision medicine, we have demonstrated clustering of CLTI patients that can be used toward a robust staging system. We provide empiric evidence for PLAN and detail about how changes in each variable affect survival and amputation-free survival.

Preoperative statin therapy is associated with higher 5-year survival after thoracic endovascular aortic repair

OBJECTIVE

Statin use is associated with higher long-term survival after abdominal aortic aneurysm repair. However, the association between statin use and survival after thoracic endovascular aortic repair (TEVAR) has not been established.

METHODS

We performed a review of prospectively collected data of all patients who had undergone TEVAR in the Vascular Quality Initiative between 2014 and 2020. We excluded patients aged <18 years, those who had presented with trauma, and those who had received custom-manufactured or physician-modified devices. We evaluated the association between preoperative statin therapy and in-hospital mortality and complications and 5-year mortality. We also analyzed the trend of preoperative statin use in elective cases for the previous 7 years. To account for nonrandom assignment to treatment, we used propensity score matching of patient characteristics, comorbidities, pathology, and urgency for preoperative statin use. We used logistic regression and Cox regression for the short-term and 5-year outcomes, respectively.

RESULTS

Of 6266 patients who had undergone TEVAR and met the inclusion criteria, 3331 (53%) patients had been taking a statin preoperatively, including 1148 of 2267 (64%) treated for aneurysmal disease. After propensity score matching, 1875 patients were in each cohort. Preoperative statin use was associated with lower rates of any perioperative complication (16.7% vs 19.6%; odds ratio, 0.82; 95% confidence interval [CI] 0.69-0.97; P = .022). Overall, preoperative statin use was also associated with lower 5-year mortality (18.8% vs 24.5%; hazard ratio [HR], 0.74; 95% CI, 0.63-0.89; P = .001). When stratified by urgency, preoperative statin use was associated with lower 5-year mortality after elective TEVAR (14.9% vs 22.4%; HR, 0.62; 95% CI, 0.49-0.79; P < .001) but not after urgent or emergent TEVAR (27.4% vs 29.1%; HR, 0.89; 95% CI, 0.70-1.14; P = .37). When stratified by pathology, preoperative statin use was associated with significantly lower 5-year mortality for patients with aneurysms (HR, 0.63; 95% CI, 0.48-0.83; P = .001). Although the mortality was also lower for patients with dissection and "other" pathology, these differences did not reach statistical significance. Between 2014 and 2019, a significant increase had occurred in statin use among patients undergoing elective TEVAR, from 56% in 2014 to 64% in 2019 (P = .007).

CONCLUSIONS

Preoperative statin therapy is associated with lower perioperative complication rates and 5-year mortality for patients undergoing TEVAR. All patients with known thoracic aortic pathology should receive statin therapy unless contraindications for the drug are present. For patients undergoing elective TEVAR, the statin prescription percentage should be considered a quality metric, and further implementation research should occur to improve preoperative statin use.

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.

A comparison of administrative data and quality improvement registries for abdominal aortic aneurysm repair

OBJECTIVE

Databases are essential in evaluating surgical outcomes and gauging the implementation of new techniques. However, there are important differences in how data from administrative databases and surgical quality improvement (QI) registries are collected and interpreted. Therefore, we aimed to compare trends, demographics, and outcomes of open and endovascular abdominal aortic aneurysm (AAA) repair in an administrative database and two QI registries.

METHODS

We identified patients undergoing open and endovascular repair of intact and ruptured AAAs between 2012 and 2015 within the National Inpatient Sample (NIS), the National Surgical Quality Improvement Program (NSQIP), and the Vascular Quality Initiative (VQI). We described the differences and trends in overall AAA repairs for each data set. Moreover, patient demographics, comorbidities, mortality, and complications were compared between the data sets using Pearson χ² test.

RESULTS

A total of 140,240 NIS patients, 10,898 NSQIP patients, and 26,794 VQI patients were included. Ruptured repairs composed 8.7% of NIS, 11% of NSQIP, and 7.9% of VQI. Endovascular aneurysm repair (EVAR) rates for intact repair (range, 83%-84%) and ruptured repair (range, 51%-59%) were similar in the three databases. In general, rates of comorbidities were lower in NIS than in the QI registries. After intact EVAR, in-hospital mortality rates were similar in all three databases (NIS 0.8%, NSQIP 1.0%, and VQI 0.8%; P = .06). However, after intact open repair and ruptured repair, in-hospital mortality was highest in NIS and lowest in VQI (intact open: NIS 5.4%, NSQIP 4.7%, and VQI 3.5% [P < .001]; ruptured EVAR: NIS 24%, NSQIP 20%, and VQI 16% [P < .001]; ruptured open: NIS 36%, NSQIP 31%, and VQI 26% [P < .001]). After stratification by intact and ruptured presentation and repair strategy, several discrepancies in morbidity rates remained between the databases. Overall, the number of cases in NSQIP represents 7% to 8% of the repairs in NIS, and the number of cases in VQI grew from 12% in 2012 to represent 23% of the national sample in 2015.

CONCLUSIONS

NIS had the largest number of patients as it represents the nationwide experience and is an essential tool to evaluate trends over time. The lower in-hospital mortality seen in NSQIP and VQI questions the generalizability of the studies that use these QI registries. However, with a growing number of hospitals engaging in granular QI initiatives, these QI registries provide a valuable resource to potentially improve the quality of care provided to all patients.

Racial and Gender Disparity in Achieving Optimal Medical Therapy for Inpatients with Peripheral Artery Disease

Best medical therapy for peripheral artery disease (PAD) includes statin and anti-platelet agents, a combination shown to decrease rates of major cardiovascular events. Despite these findings, many patients remain undertreated and the objective of this project was to investigate the rate of initiating anti-platelet and statin therapy for inpatients newly diagnosed with PAD with a focus on disparities by race and sex. A retrospective chart review of inpatients with newly diagnosed PAD was performed between January 1, 2016 to December 31, 2016 at a single institution. Demographics and comorbid conditions were collected. Primary outcomes included antiplatelet and statin prescription at discharge. The 44 patients included in this study were predominantly male (59% vs. 41%) and African American (61% vs. 39%). Between admission and discharge, prescriptions rose from 70% to 82% for statin and 82% to 91% for anti-platelet agents. Vascular specialists were more successful than non-vascular specialists at initiating medical therapy, with statin prescriptions increasing 22% and anti-platelet prescriptions climbing 23% for those admitted to a vascular specialist. Interestingly, when the ABI was reported in the normal range, rates of statin initiation were particularly compromised at only 40%. For the total patient sample, those discharged without a statin were more commonly African American (63%) and the majority were female (67%). All patients discharged without an antiplatelet were African American and 50% were females. Despite national guidelines, patients with PAD continue to be discharged without optimal medical therapy. This study suggests that obstacles to initiation may include race, sex, admitting service, or presence of a normal ABI. Further investigation is warranted to determine effective avenues for provider education and system-wide initiatives.

Big data in vascular surgery: registries, international collaboration and future directions

Given the increasing availability of large data set, small single-institutional series raise decreasing attention. Rapid expansion of technology from electronic medical records to easily accessible internet access, and widespread use and acceptance of registries in the medical world has allowed for research and quality improvement efforts using 'big data'. Big data, although technically not defined, typically refers to large databases that can be used to investigate common or rare disease processes or outcomes, describe variation in clinical practices across and between different specialties at various practice location, whilst allowing important information about trends over time. Big data have allowed investigators to quickly assimilate cohorts of patients and/or procedures to answer current questions, with more complete population representation and improved generalizability whilst decreasing the likelihood of power problems and type II errors. On the other hand, pitfalls still exist with the growing problem of hypothesis fishing, lack of granularity and the fear by many clinicians that registry transparency may have already gone too far, where surgery groups or individual surgeon outcomes are readily available to patients and referring providers. Within vascular surgery specifically, big data have expanded over the last decade and now includes regional, national and global registries that have major benefits of gathering specific clinical and procedural information within vascular surgery. In this review, we highlight the main vascular surgery registries and recap a few success stories of how the registries have been leveraged to benefit discovery, quality improvement and ultimately patient care. Additionally, we outline future directions that will be imperative for continued expansion, acceptance and adoption of 'big data' utilization inpatients with vascular disease.

Socioeconomically Distressed Communities Index independently predicts major adverse limb events after infrainguinal bypass in a national cohort

BACKGROUND

Socioeconomic status is a major determinant of not only quality of life, but also mortality and health care-related outcomes. We hypothesized that patients coming from distressed communities would have worse short- and long-term limb related outcomes after infrainguinal bypass.

METHODS

The infrainguinal bypass national Vascular Quality Initiative datasets for 2003 to 2018 were used. Clinical data were paired with the Distressed Communities Index (DCI) score before extraction. The DCI accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies at the zip code level, with a range of 0 (no distress) to 100 (severe distress). Severely distressed communities were defined as DCI greater than 75 for univariate analysis. Hierarchical multivariable modeling adjusted for baseline and operative risk factors, and clustering at the hospital level.

RESULTS

The 9711 patients who underwent infrainguinal bypass from severely distressed communities (out of 40,109 total) were younger, more likely to smoke, disproportionately African American, with more comorbid disease (all P < .05). Patients from less distressed communities had lower rates of critical limb ischemia (56% DCI ≤ 75 vs 60% DCI > 75; P < .0001) and prior amputation (4.7 vs 6.3%; P < .0001). There was no difference in in-hospital mortality (1.3% vs 1.3%; P = .906) or major adverse cardiovascular events (4.1% vs 3.7%; P = .097). However, patients from distressed communities had higher rates of major adverse limb events (MALE; 11.7% vs 14.4%; P < .0001), and the components amputation, thrombectomy, and revision. After risk adjustment, DCI remained an independent predictor of in-hospital MALE (odds ratio, 1.05 per 25 DCI points; 95% confidence interval [CI], 1.02-1.08; P = .001) and long-term MALE (hazard ration [HR] 1.02; 95% CI, 1.00-1.04; P = .045). DCI is predictive of long-term graft occlusion (HR, 1.04; 95% CI, 1.00-1.07; P = .028) and amputation (HR, 1.09; 95% CI, 1.06-1.12; P < .0001).

CONCLUSIONS

The DCI is an independent predictor of MALE after infrainguinal bypass. Patients from distressed communities are at an increased risk of long-term graft occlusion, which is disproportionately treated with amputation instead of surgical limb-saving alternatives. Socioeconomic factors impact vascular disease and surgical outcomes with disparities that warrant further investigation.

Utility of the Vascular Quality Initiative in improving quality of care in Canadian patients undergoing vascular surgery

The Vascular Quality Initiative (VQI) is a national cooperative quality-improvement initiative designed to evaluate processes of care and outcomes in vascular surgery. The purpose of this report is to show the utility of such a database to provide insight into the standard of care provided, to highlight areas of local quality improvement, to benchmark our data against local, regional and national trends, and to ultimately improve safety in Canadian patients undergoing vascular surgery. We present the history of the database, its spread in the Canadian health care system and examples of quality improvements achieved from analyses of data recorded and retrieved from the VQI. Using the VQI, our institution was able to decrease the length of stay after endovascular aneurysm repair, decrease the contrast volume in endovascular aneurysm repair, save on costs, and provide medium-term outcome data on peripheral vascular interventions and smoking cessation strategies. The VQI is a powerful tool to improve patient safety and quality in vascular surgery. Its ability to create local regional improvement groups fosters a quality-focused culture and is important for Canadian patients.

Analysis of Thirty-Day Readmission after Infrainguinal Bypass

BACKGROUND

The Vascular Study Group of New England (VSGNE) conducted a pilot study evaluating the feasibility of 30-day data collection in patients undergoing infrainguinal bypass (INFRA) which was subsequently expanded to include a limited number of additional sites within the Vascular Quality Initiative (VQI). The purpose of our study was to use these data to evaluate the incidence of 30-day readmission after infrainguinal bypass. A secondary goal of the study was to perform a critical appraisal of the data elements and definitions in the 30-day dataset.

METHODS

All infrainguinal bypass procedures performed during the pilot study period (7/2008 and 4/2016) were identified and merged with a dataset containing the 30-day data. Incidence and types of readmission were assessed. The primary endpoint was 30-day readmission, defined as any hospital readmission within 30 days of index operation; unplanned 30-day readmission was the secondary endpoint. Covariates tested for association with the primary and secondary endpoints included patient demographics, comorbidities, procedural, and postoperative characteristics. Variables significant on univariate screen (P < 0.2) were evaluated with logistic regression to identify independent determinants.

RESULTS

Of 9,847 infrainguinal bypass patients, 5,842 (59%) patients were identified with 30-day data, and 907 (16%) were readmitted within 30 days. Of readmissions, 675 (85%) were unplanned. Potentially modifiable independent determinants of any 30-day readmission included 30-day surgical site infection (SSI) (odds ratio [OR]: 10, 95% confidence interval [CI]: 8.2-12, P < 0.0001), postoperative acute kidney injury (OR: 1.7, 95% CI: 1.2-2.5, P = 0.002), and discharge anticoagulation (OR: 1.2, 95% CI: 1.04-1.5; P = 0.02). Predictors of unplanned 30-day readmission were very similar but identified in-hospital major amputation as an additional independent predictor (OR: 2.8, 95% CI: 1.6-4.9, P = 0.0002).

CONCLUSIONS

This study demonstrates the interest in, and value of, 30-day data collection in VSGNE/VQI and documents the frequency of readmission after infrainguinal bypass. Readmission within 30 days is strongly associated with SSI, stressing the importance of efforts to decrease this complication. Given that many other predictors are unmodifiable, 30-day readmission is only appropriate as a quality metric if it is risk adjusted using large, real-world datasets such as VQI. Lessons learned from this analysis can be used to select optimal 30-day data elements.

Socioeconomic Distressed Communities Index associated with worse limb-related outcomes after infrainguinal bypass

OBJECTIVE

Several studies have demonstrated that socioeconomic factors may affect surgical outcomes. Analyses in vascular surgery have been limited by the availability of individual or community-level socioeconomic data. We sought to determine whether the Distressed Communities Index (DCI), a composite socioeconomic ranking by ZIP code, could predict short- and long-term outcomes for patients with peripheral artery disease.

METHODS

All Virginia Quality Initiative patients (n = 2578) undergoing infrainguinal bypass (2011-2017) within a region of 17 centers were assigned a composite DCI score. The score was developed by the Economic Innovation Group and is normally distributed from 0 (no distress) to 100 (severe distress) based on measures of community unemployment, education level, poverty rate, median income, business growth, and housing vacancies. Severely distressed communities were defined as the top quartile DCI (>75). Hierarchical regression assessed short-term outcomes, and time-to-event analyses assessed long-term results.

RESULTS

Infrainguinal bypass patients in this study came from disproportionately distressed communities, with 29% of patients living within the highest distress DCI quartile (P < .0001), with high variability by hospital (DCI range, 12-67). These patients from severely distressed areas were younger, more likely to smoke, and disproportionately African American and had higher rates of medical comorbidities (all P < .05). Whereas patients from severely distressed communities had an equivalent rate of 30-day major adverse cardiac and cerebrovascular events (5% vs 4%; P = .86), they had increased rates of major adverse limb events (MALEs) at 13% vs 10% (P = .03). This trend persisted in the long term, with higher 1-year estimates of MALEs (21% vs 17%; P = .01) as well as the components of amputation (17% vs 12%; P = .006) and thrombectomy (11% vs 6%; P = .002). Patients with high socioeconomic distress also had higher rates of occlusion (17% vs 11%; P = .003).

CONCLUSIONS

In this study, patients from severely distressed communities were found to have increased rates of MALEs, an association that persisted long term. Mitigating risk associated with socioeconomic determinants of health has the potential to improve outcomes for patients with peripheral artery disease.

Advances in the Management of Peripheral Artery Disease

PURPOSE OF REVIEW

This paper provides a concise update on the management of peripheral artery disease (PAD).

RECENT FINDINGS

PAD continues to denote a population at high risk for mortality but represents a threat for limb loss only when associated with foot ulcers, gangrene, or infections. Performing either angiogram or non-invasive testing for all patients with foot ulcers, gangrene, or foot infections will help increase the detection of PAD, and refined revascularization strategies may help optimize wound healing in this patient group. Structured exercise programs are becoming available to more patients with claudication as methods to improve adherence to community-based exercise programs will improve. Finally, ensuring more patients with PAD receive aspirin therapy and statins may improve long-term survival, while further research will help determine if adding newer antiplatelet or anticoagulant medications may reduce leg amputations in selected patients. Clinicians should have a low threshold to obtain an angiogram and to pursue revascularization in patients with foot ulcers, gangrene, or foot infections. In patients with claudication, clinicians should maximize the benefits derived from exercise therapy and medical management before offering percutaneous or surgical revascularization.

Statin therapy is associated with higher long-term but not perioperative survival after abdominal aortic aneurysm repair

BACKGROUND

Although preoperative and perioperative statin therapy improves postoperative outcomes in several populations, few data examine its association with survival after abdominal aortic aneurysm (AAA) repair. In addition, no data exist regarding the benefits of starting statins in patients with AAA not currently taking them.

METHODS

We performed a registry-based study of all patients undergoing repair of AAAs in the Vascular Quality Initiative between 2003 and 2017 without documented statin intolerance. In our primary analysis, we evaluated the association between preoperative statin therapy and long-term mortality, 30-day mortality, and in-hospital myocardial infarction and stroke. As a secondary analysis, we studied the cohort of patients not taking a statin preoperatively and compared their long-term mortality on the basis of whether they were discharged on a statin. To account for nonrandom assignment to treatment, we constructed propensity scores and applied inverse probability weighting.

RESULTS

We identified 40,452 AAA repairs, of which 37,950 fit our entry criteria (29,257 endovascular and 8693 open). Overall, 25,997 patients (69%) were taking a statin preoperatively, with patients undergoing endovascular aneurysm repair more frequently taking a statin than those undergoing open repair (69% compared with 66%; P < .001). After propensity weighting, preoperative statin therapy was not associated with 30-day death or in-hospital stroke or myocardial infarction. However, patients taking statins preoperatively experienced higher adjusted 1-year (94% vs 90%) and 5-year (85% vs 81%) survival from the date of surgery compared with those who were not (P < .001 overall), although subgroup analysis showed that this applied only to intact or symptomatic aneurysms. Of the 11,941 patients not taking a statin preoperatively and discharged alive, 2910 (24%) started on a statin before discharge. In our secondary analysis of the subset of patients not taking statins preoperatively, those initiated on a statin before discharge experienced higher survival at 1 year (94% vs 91%) and 5 years (89% vs 81%; P < .001 overall) than those who remained off statin therapy, with the greatest absolute long-term survival difference in patients with rupture (87% vs 62%; P < .001 overall).

CONCLUSIONS

Preoperative statin therapy is associated with higher long-term survival but not perioperative mortality and morbidity in patients undergoing AAA repair, and initiating statin therapy in previously statin-naive patients is associated with markedly higher survival. All patients with AAAs without contraindications should receive statin therapy. In patients not taking a statin at the time of AAA repair, clinicians should consider initiating one before discharge.

Statin therapy improved long-term prognosis in patients with major non-cardiac vascular surgeries: a systematic review and meta-analysis

OBJECTIVE

To investigate whether statin intervention will improve the long-term prognosis of patients undergoing major non-cardiac vascular surgeries.

METHODS

Major database searches for clinical trials enrolling patients undergoing major non-cardiac vascular surgeries, including lower limb revascularization, carotid artery surgeries, arteriovenous fistula, and aortic surgeries, were performed. Subgroup analyses, stratified by surgical types or study types, were employed to obtain statistical results regarding survival, patency rates, amputation, and cardiovascular and stroke events. Odds ratio (ORs) and 95% confidence intervals (CIs) were calculated by Review Manager 5.3. Sensitivity analysis, publication bias and meta-regression were conducted by Stata 14.0.

RESULTS

In total, 34 observational studies, 8 prospective cohort studies and 4 randomized controlled clinical trials (RCTs) were enrolled in the present analysis. It was demonstrated that statin usage improved all-cause mortality in lower limb, carotid, aortic and mixed types of vascular surgery subgroups compared with those in which statins were not used. Additionally, the employment of statins efficiently enhanced the primary and secondary patency rates and significantly decreased the amputation rates in the lower limb revascularization subgroup. Furthermore, for other complications, statin intervention decreased cardiovascular events in mixed types of vascular surgeries and stroke incidence in the carotid surgery subgroup. No significant publication bias was observed. The meta-regression results showed that the morbidity of cardiovascular disease or the use of aspirin might affect the overall estimates in several subgroups.

CONCLUSIONS

This meta-analysis demonstrated that statin therapy was associated with improved survival rates and patency rates and with reduced cardiovascular or stroke morbidities in patients who underwent non-cardiac vascular surgeries.

Abdominal Aortic Aneurysm: Evolving Controversies and Uncertainties

Abdominal aortic aneurysm (AAA) is defined as a permanent dilatation of the abdominal aorta that exceeds 3 cm. Most AAAs arise in the portion of abdominal aorta distal to the renal arteries and are defined as infrarenal. Most AAAs are totally asymptomatic until catastrophic rupture. The strongest predictor of AAA rupture is the diameter. Surgery is indicated to prevent rupture when the risk of rupture exceeds the risk of surgery. In this review, we aim to analyze this disease comprehensively, starting from an epidemiological perspective, exploring etiology and pathophysiology, and concluding with surgical controversies. We will pursue these goals by addressing eight specific questions regarding AAA: (1) Is the incidence of AAA increasing? (2) Are ultrasound screening programs for AAA effective? (3) What causes AAA: Genes versus environment? (4) Animal models: Are they really relevant? (5) What pathophysiology leads to AAA? (6) Indications for AAA surgery: Are surgeons over-eager to operate? (7) Elective AAA repair: Open or endovascular? (8) Emergency AAA repair: Open or endovascular?

Preoperative dementia is associated with increased cost and complications after vascular surgery

OBJECTIVE

Dementia represents a major risk factor for medical complications and has been linked to higher rates of complication after surgery. Given the systemic nature of vascular disease, medical comorbidities significantly increase cost and complications after vascular surgery. We hypothesize that the presence of dementia is an independent predictor of increased postoperative complications and higher health care costs after vascular surgery.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing vascular surgery at a single academic medical center from 2012 to 2017. All modules were included (open abdominal aortic aneurysm, suprainguinal bypass, lower extremity bypass, amputation, carotid endarterectomy, endovascular aortic aneurysm repair, thoracic endovascular aortic aneurysm repair, and peripheral endovascular intervention). An institutional clinical data repository was queried to identify patients with International Classification of Diseases, Ninth Revision diagnosis codes for dementia as well as total hospital cost and long-term survival using Social Security records from the Virginia Department of Health. Hierarchical logistic and linear regression models were fit to assess risk-adjusted predictors of any complication and inflation-adjusted cost. Kaplan-Meier and Cox proportional hazards models were used for survival analysis.

RESULTS

A total of 2318 patients underwent vascular surgery and were captured by the Vascular Quality Initiative during the past 5 years, with 88 (3.8%) having a diagnosis of dementia. Patients with dementia were older and had higher rates of medical comorbidities, and the most common procedure was major amputation. In addition, dementia patients had a significantly higher rate of any complication (52% vs 16%; P < .0001) and increased 90-day mortality (14% vs 4.8%; P = .0002). Furthermore, dementia was associated with significant resource utilization, including preoperative length of stay (LOS), postoperative LOS, intensive care unit LOS, and inflation-adjusted total hospital cost (all P < .0001). Hierarchical modeling demonstrated that dementia was the strongest preoperative predictor for any complication (odds ratio, 8.64; P < .0001) and had the largest risk-adjusted impact on total hospital cost ($22,069; P < .0001). Finally, survival analysis demonstrated that dementia is independently associated with reduced survival after vascular surgery (hazard ratio, 1.37; P = .018).

CONCLUSIONS

This study demonstrated that dementia is one of the strongest predictors of any complication and increased hospital cost after vascular surgery. Given the high risk of clinical and financial maladies, patients with dementia should be carefully considered and counseled before undergoing vascular surgery.

Open and endovascular aneurysm repair in the Society for Vascular Surgery Vascular Quality Initiative

The Society for Vascular Surgery Vascular Quality Initiative is a patient safety organization and a collection of procedure-based registries that can be utilized for quality improvement initiatives and clinical outcomes research. The Vascular Quality Initiative consists of voluntary participation by centers to collect data prospectively on all consecutive cases within specific registries which physicians and centers elect to participate. The data capture extends from preoperative demographics and risk factors (including indications for operation), through the perioperative period, to outcomes data at up to 1-year of follow-up. Additionally, longer-term follow-up can be achieved by matching with Medicare claims data, providing long-term longitudinal follow-up for a majority of patients within the Vascular Quality Initiative registries. We present the unique characteristics of the Vascular Quality Initiative registries and highlight important insights gained specific to open and endovascular abdominal aortic aneurysm repair.

Adherence to lipid management guidelines is associated with lower mortality and major adverse limb events in patients undergoing revascularization for chronic limb-threatening ischemia

OBJECTIVE

The 2013 American College of Cardiology/American Heart Association lipid management guidelines recommend high-intensity statins for all patients ≤75 years old with chronic limb-threatening ischemia (CLTI) and moderate-intensity statins for CLTI patients >75 years old without contraindications or on dialysis, but these recommendations are based primarily on coronary and stroke data. We aimed to validate these guidelines in patients with CLTI and to assess current adherence to these recommendations.

METHODS

We identified all patients with CLTI who underwent first-time revascularization (endovascular or surgical) at Beth Israel Deaconess Medical Center from 2005 to 2014. Patients were classified as taking high-intensity, moderate-intensity, low-intensity, or no statin postoperatively. Outcomes included death and major adverse limb event (MALE). Propensity scores were calculated for the probability of receiving guideline-recommended intensity of statin therapy to account for nonrandom assignment of treatments. Cox regression models were constructed and adjusted for the propensity scores and further adjusted for strong potential confounders.

RESULTS

After excluding patients on hemodialysis (n = 252), we identified 1019 limbs from 931 patients with a median follow-up of 380 days. Patients discharged on the recommended statin intensity had higher rates of preoperative statin use, coronary artery disease, chronic kidney disease, stroke, atrial fibrillation, congestive heart failure, and coronary artery bypass grafting; they had lower smoking rates and were less likely to be ambulatory preoperatively. Overall, only 35% were taking the recommended statin dosage: 55% of those >75 years old and 20% of those ≤75 years old. In multivariable analysis including propensity scores where appropriate, discharge on any statin was associated with lower mortality (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.60-0.90; P < .01). Discharge on the recommended intensity of statin therapy was associated with lower mortality (HR, 0.73; 95% CI, 0.60-0.99; P < .05) and lower MALE rate (HR, 0.71; 95% CI, 0.51-0.97; P < .05). Patients >75 years old and ≤75 years old accrued similar benefit. In patients >75 years old, moderate-intensity statin therapy was associated with lower rates of death and MALE compared with high-intensity therapy but did not reach statistical significance.

CONCLUSIONS

Use of the recommended intensity of statin therapy in compliance with 2013 American College of Cardiology/American Heart Association lipid management guidelines is associated with significantly improved survival and lower MALE rate in patients undergoing revascularization for CLTI. Adherence to current guidelines is an appealing target for quality improvement.

Risk Factors for Suboptimal Utilization of Statins and Antiplatelet Therapy in Patients Undergoing Revascularization for Symptomatic Peripheral Arterial Disease

BACKGROUND

The objective of this study was to identify risk factors for suboptimal medical therapy (defined as reported antiplatelet and statin use) among patients undergoing lower extremity bypass (LEB) and peripheral vascular interventions (PVIs) for symptomatic peripheral arterial disease (PAD).

METHODS

The Vascular Study Group of Greater New York (VSGGNY) database was used to identify all patients undergoing PVI or LEB for PAD (2011-2013). Bivariate analyses were performed to identify characteristics of patients who were not prescribed statins and/or antiplatelet agents before revascularization. Multivariate relative risk regression models were developed to identify patients at risk for suboptimal therapy, with regards to antiplatelet and statin therapy.

RESULTS

About 1,030 patients underwent endovascular therapy (n = 822; 80%) or surgical bypass (n = 208; 20%) for symptomatic PAD (57.2% claudication; 15% rest pain and 27.8% tissue loss). Overall, preoperative statin use was observed in 59%. Preoperative antiplatelet therapy was observed in 79% of patients. Bivariate analysis revealed comparatively reduced statin use among patients without other cardiovascular risk factors including hypertension (63% vs. 39.3%; P < 0.0001) and coronary artery disease (CAD) with or without prior cardiac revascularization (coronary artery bypass grafting [CABG]/percutaneous coronary intervention [PCI]; 75.2% vs. 47.4%; P < 0.0001). Multivariate relative risk regression confirmed higher rates of statin use among patients with other cardiovascular risk factors including hypertension (1.14 [1.02-1.27]; P = 0.02) and CAD with prior CABG/PCI (1.22 [1.13-1.31]; P < 0.0001). Reduced statin use was observed in patients over 80 years old. (0.92 [0.84-0.1.0]; P = 0.059). By multivariate regression, antiplatelet therapy use was associated with CAD and/or prior CABG/PCI (1.11 [1.04-1.17]; P = 0.0015) and prior peripheral revascularization (1.07 [1.01-1.13]; P = 0.03).

CONCLUSIONS

Patients with symptomatic PAD, but without an antecedent cardiovascular history, are less likely to be optimally managed with statins and antiplatelet therapy preoperatively. Given the established role of these medications in the optimal medical management of patients with PAD, this presents an opportunity for improvement in the overall vascular care of patients undergoing intervention for symptomatic PAD at VSGGNY centers.

Quality and Safety in Health Care, Part XXIV: More on Vascular Surgery

The use of registries such as the Vascular Quality Initiative and its regional groups, such as the Vascular Study Group of New England, have been very helpful in investigating problems related to quality and safety in vascular surgery. This article discusses some of their contributions regarding carotid artery procedures, the use of certain medications in the perioperative period, and the risk factors for sustaining a major cardiac complication while in the hospital after vascular surgery.

Thresholds for Abdominal Aortic Aneurysm Repair in England and the United States

BACKGROUND

Thresholds for repair of abdominal aortic aneurysms vary considerably among countries.

METHODS

We examined differences between England and the United States in the frequency of aneurysm repair, the mean aneurysm diameter at the time of the procedure, and rates of aneurysm rupture and aneurysm-related death. Data on the frequency of repair of intact (nonruptured) abdominal aortic aneurysms, in-hospital mortality among patients who had undergone aneurysm repair, and rates of aneurysm rupture during the period from 2005 through 2012 were extracted from the Hospital Episode Statistics database in England and the U.S. Nationwide Inpatient Sample. Data on the aneurysm diameter at the time of repair were extracted from the U.K. National Vascular Registry (2014 data) and from the U.S. National Surgical Quality Improvement Program (2013 data). Aneurysm-related mortality during the period from 2005 through 2012 was determined from data obtained from the Centers for Disease Control and Prevention and the U.K. Office of National Statistics. Data were adjusted with the use of direct standardization or conditional logistic regression for differences between England and the United States with respect to population age and sex.

RESULTS

During the period from 2005 through 2012, a total of 29,300 patients in England and 278,921 patients in the United States underwent repair of intact abdominal aortic aneurysms. Aneurysm repair was less common in England than in the United States (odds ratio, 0.49; 95% confidence interval [CI], 0.48 to 0.49; P<0.001), and aneurysm-related death was more common in England than in the United States (odds ratio, 3.60; 95% CI, 3.55 to 3.64; P<0.001). Hospitalization due to an aneurysm rupture occurred more frequently in England than in the United States (odds ratio, 2.23; 95% CI, 2.19 to 2.27; P<0.001), and the mean aneurysm diameter at the time of repair was larger in England (63.7 mm vs. 58.3 mm, P<0.001).

CONCLUSIONS

We found a lower rate of repair of abdominal aortic aneurysms and a larger mean aneurysm diameter at the time of repair in England than in the United States and lower rates of aneurysm rupture and aneurysm-related death in the United States than in England. (Funded by the Circulation Foundation and others.).

Significant regional variation exists in morbidity and mortality after repair of abdominal aortic aneurysm

OBJECTIVE

Limited data exist comparing perioperative morbidity and mortality after open and endovascular abdominal aortic aneurysm (AAA) repair (EVAR) among regions of the United States. This study evaluated the regional variation in mortality and perioperative outcomes after repair of AAAs.

METHODS

The Vascular Quality Initiative (VQI) was used to identify patients undergoing open AAA repair and EVAR between 2009 and 2014. Ruptured and intact aneurysms were evaluated separately, and the analysis of intact aneurysms was limited to infrarenal AAAs. All 16 regions of the VQI were deidentified, and those with <100 open repairs were combined to eliminate the effect of low-volume regions. Regional variation was evaluated using χ² and Fisher exact tests. Regional rates were compared against current quality benchmarks.

RESULTS

Perioperative outcomes from 14 regions were compared. After open repair of intact aneurysms, no significant variation was seen in 30-day or in-hospital mortality; however, multiple regions exceeded the Society for Vascular Surgery benchmark for in-hospital mortality after open repair of intact aneurysms of <5% (range, 0%-7%; P = .55). After EVAR, all regions met the Society for Vascular Surgery benchmark of <3% (range, 0%-1%; P = .75). Significant variation in in-hospital mortality existed after open (14%-63%; P = .03) and endovascular (3%-32%; P = .03) repair of ruptured aneurysms across the VQI regional groups. After repair of intact aneurysms, wide variation was seen in prolonged length of stay (>7 days for open repair: 32%-53%, P = .54; >2 days for EVAR: 16-43%, P < .01), transfusion (open: 10%-35%, P < .01; EVAR: 7%-18%, P < .01), use of vasopressors (open: 19%-37%, P < .01; EVAR: 3%-7%, P < .01), and postoperative myocardial infarction (open: 0%-13%, P < .01; EVAR: 0%-3%, P < .01). After open repair, worsening renal function (6%-18%; P = .04) and respiratory complications (6%-20%; P = .20) were variable across regions. The frequency of endoleak at completion of EVAR also had considerable variation (15%-38%; P < .01).

CONCLUSIONS

Despite limited variation, multiple regions do not meet current benchmarks for in-hospital mortality after open AAA repair for intact aneurysms. Significant regional variation exists in perioperative outcomes and length of stay, and mortality is widely variable after repair for rupture. These data identify important areas for quality improvement initiatives and clinical practice guidelines.