Analysis of Medicare Payments and Patient Outcomes With Pre-Operative Imaging for Carotid Endarterectomy.

OBJECTIVE: The use of radiographic evaluation of carotid disease may vary, and current guidelines do not strongly recommend the use of cross-sectional imaging (CSI) prior to surgical intervention. We sought to describe the trends in preoperative carotid imaging and evaluate the associated clinical outcomes and Medicare payments for patients undergoing carotid endarterectomy (CEA) for asymptomatic carotid disease. METHODS: We used a 20% Medicare sample from 2006 to 2014 identifying patients undergoing CEA for asymptomatic disease. We evaluated preoperative carotid ultrasound and CSI use: CT or MRI of the neck prior to CEA. We calculated average payments of each study from the carrier file and revenue center file. Imaging payments included both the professional component (PC) and the technical component (TC). Claims with a reimbursement of $0 and studies where payment for both the TC and PC could not be identified were excluded from the overall calculation to determine average payment per study. Inpatient reimbursements according to DRG 37-39 were calculated. We compared hospital length of stay (LOS), in hospital stroke, carotid re-exploration, and mortality according to CSI use. RESULTS: A total of 58,993 CEAs were identified with pre-operative carotid imaging. The average age was 74.8 ± 7.5 years, and 56.0% were men. A total of 19,678 (33%) patients had ultrasound alone with an average of (2.4 ± 1.9) exams prior to CEA. A total of 39,315 patients underwent CSI prior to CEA with 2.5 ± 2.1 ultrasounds, 0.95 ± 0.86 neck CTs and 0.47 ± 0.7 MRIs per patient. The average payment for ultrasound was $140 ± 40, $282 ± 94 for CT and $410 ± 146 for MRI. The average inpatient reimbursements were $7,413 ± 4,215 for patients without CSI compared with $7,792 ± 3,921 for patients with CSI, P < 0.001. The average LOS during CEA admission was 2.5 ± 3.7days. Patients with CSI had a slightly lower percentage of patients being discharged by postoperative day 2 compared with ultrasound alone (88.9% vs. 91.5%, respectively, P < 0.001). The overall in-hospital stroke rate was 0.38% and carotid re-exploration rate was 1.0% and there was no statistical significant difference between groups. Median follow-up was 3.9 years, and mortality at 8 years was 50% and did not statistically differ between groups. CONCLUSIONS: Our analysis found preoperative imaging to include CSI in nearly two-thirds of patients prior to CEA for asymptomatic disease. As imaging and inpatient payments were higher with patients with CSI further work is needed to understand when CSI is appropriate prior to surgical intervention to appropriately allocate healthcare resources.

Improving Quality of Carotid Interventions: Identifying Hospital-Level Structural Factors that can Improve Outcomes.

BACKGROUND: "Structural factors" relating to organization of hospitals may affect procedural outcomes. This study's aim was to clarify associations between structural factors and outcomes after carotid endarterectomy (CEA) and carotid endarterectomy stenting (CAS). METHODS: A systematic review of studies published in English since 2005 was conducted. Structural factors assessed were as follows: population size served by the vascular department; number of hospital beds; availability of dedicated vascular beds; established clinical pathways; surgical intensive care unit (SICU) size; and specialty of surgeon/interventionalist. Primary outcomes were as follows: mortality; stroke; cardiac complications; length of hospital stay (LOS); and cost. RESULTS: There were 11 studies (n = 95,100 patients) included in this systematic review. For CEA, reduced mortality (P < 0.0001) and stroke rates (P = 0.001) were associated with vascular departments serving >75,000 people. Larger hospitals were associated with lower mortality, stroke rate, and cardiac events, compared with smaller hospitals (less than 130 beds). Provision of vascular beds after CEA was associated with lower mortality (P = 0.0008) and fewer cardiac events (P = 0.03). Adherence to established clinical pathways was associated with reduced stroke and cardiac event rates while reducing CEA costs. Large SICUs (≥7 beds) and dedicated intensivists were associated with decreased mortality after CEA while a large SICU was associated with reduced stroke rate (P = 0.001). Vascular surgeons performing CEA were associated with lower stroke rates and shorter LOS (P = 0.0001) than other specialists. CAS outcomes were not influenced by specialty but costless when performed by vascular surgeons (P < 0.0001). CONCLUSIONS: Structural factors affect CEA outcomes, but data on CAS were limited. These findings may inform reconfiguration of vascular services, reducing risks and costs associated with carotid interventions.

Role of adjuvant carotid ultrasound in women undergoing stress echocardiography for the assessment of suspected coronary artery disease.

OBJECTIVE: Due to the low prevalence of obstructive coronary artery disease (CAD) in women, stress testing has a relatively low predictive value for this. Additionally, conventional cardiovascular risk scores underestimate risk in women. This study sought to evaluate the role of atherosclerosis assessment using carotid ultrasound (CU) in women attending for stress echocardiography (SE). METHODS: This was a prospective study in which consecutive women with recent-onset suspected angina, who were referred for clinically indicated SE, underwent CU. RESULTS: 415 women (mean age 61±10 years, 29% diabetes mellitus, mean body mass index 28) attending for SE underwent CU. 47 women (11%) had inducible wall motion abnormalities, and carotid disease (CD) was present in 46% (carotid plaque in 41%, carotid intima-media thickness >75th percentile in 15%). Women with CD were older (65 vs 58 years, p<0.001), and more likely to have diabetes (41% vs 21%, p=0.001), hypertension (67% vs 36%, p<0.01) and a higher pretest probability of CAD (59% vs 41%, p<0.001). 40% of women classified as low Framingham risk were found to have evidence of CD.The positive predictive value of SE for flow-limiting CAD was 51%, but with the presence of carotid plaque, this was 71% (p<0.01). Carotid plaque (p=0.004) and ischaemia (p=0.01) were the only independent predictors of >70% angiographic stenosis. In women with ischaemia on SE and no carotid plaque, the negative predictive value for flow-limiting disease was 88%.During a follow-up of 1058±234 days, there were 15 events (defined as all-cause mortality, non-fatal myocardial infarction, heart failure admissions and late coronary revascularisation). Age (HR 1.07 (1.00-1.15), p=0.04), carotid plaque burden (HR 1.65 (1.36-2.00), p<0.001) and ischaemic burden (HR 1.41 (1.18-1.68), p<0.001) were associated with outcome. There was a stepwise increase in events/year from 0.3% when there were no ischaemia and atherosclerosis, 1.1% when there was atherosclerosis and no ischaemia, 2.2% when there was ischaemia and no atherosclerosis and 10% when there were both ischaemia and atherosclerosis (p<0.001). CONCLUSION: CU significantly improves the accuracy of SE alone for identifying flow-limiting disease on coronary angiography, and improves risk stratification in women attending for SE, as well identifying a subset of women who may benefit from primary preventative measures.

Clinical impact of sex on carotid revascularization.

BACKGROUND: The impact of sex in the management of carotid disease is unclear in the current literature. Therefore, we evaluated the effect of sex on perioperative outcomes following carotid endarterectomy (CEA) and carotid artery stenting (CAS). METHODS: We included patients who underwent CEA or CAS between 2012 and 2017 in the Vascular Quality Initiative database. Our primary outcome was perioperative stroke/death. Secondary outcomes were in-hospital stroke, 30-day mortality, and in-hospital MI. We compared perioperative outcomes between female and male patients, stratified by treatment modality and symptom status, and used multivariable regression to account for differences in baseline characteristics. RESULTS: A total of 83,436 patients underwent either a CEA (71,383) or CAS (12,053). Asymptomatic and symptomatic CEA females were less likely to be on a preoperative antiplatelet agent, when compared to males. Females overall, were less likely to be on a preoperative statin and more likely to have chronic obstructive pulmonary disease. Within the CAS cohort, females were more likely to have a previous ipsilateral CEA. There were no differences between males and females in major adverse events following CEA for asymptomatic disease. Following CEA for symptomatic disease, there was no difference in stroke/death rate or in-hospital stroke. However, females experienced a higher 30-mortality after adjustment (univariate: 1.0% vs 0.7%, P = .04; adjusted: odds ratio [OR], 1.4:1.02-1.94). Following CAS for asymptomatic disease, females experienced a higher rate of perioperative stroke/death (2.9% vs 1.9% P = .02; OR, 1.5: 1.05-2.03) and in-hospital stroke (2.1% vs 1.2% P = .01; OR, 1.8: 1.20-2.60). There were no differences in outcomes for symptomatic females vs males undergoing CAS. CONCLUSIONS: Females with carotid disease less frequently receive optimal medical treatment with antiplatelet agents and statins. This is an important target area for quality improvement issue in both females and males. Furthermore, among symptomatic CEA patients the female sex is associated with higher mortality and among asymptomatic CAS patients, females experience higher rates of stroke/death. These findings suggest that careful patient selection is necessary in the treatment of female patients. Quality improvement projects should be created to further investigate and eliminate the disparities of optimal medical management between the sexes.

A comparative analysis of long-term mortality after carotid endarterectomy and carotid stenting.

BACKGROUND: The value of carotid intervention is predicated on long-term survival for patients to derive a stroke prevention benefit. Randomized trials report no significant difference in survival after carotid endarterectomy (CEA) vs carotid artery stenting (CAS), whereas observational studies of "real-world" outcomes note that CEA is associated with a survival advantage. Our objective was to examine long-term mortality after CEA vs CAS using a propensity-matched cohort. METHODS: We studied all patients who underwent CEA or CAS within the Vascular Quality Initiative from 2003 to 2013 (CEA, n = 29,235; CAS, n = 4415). Long-term mortality information was obtained by linking patients in the registry to their respective Medicare claims file. We assessed the long-term rate of mortality for CEA and CAS using Kaplan-Meier estimation. We assessed the crude, adjusted, and propensity-matched (total matched pairs, n = 4261) hazard ratio (HR) of mortality for CEA vs CAS using Cox regression. RESULTS: The unadjusted Kaplan-Meier estimated 5-year mortality was 14.0% for CEA and 18.3% for CAS. The crude HR of all-cause mortality for CEA vs CAS was 0.75 (95% confidence interval [CI], 0.70-0.81), indicating that patients who underwent CEA were 25% less likely to die before those who underwent CAS. This survival advantage persisted after adjustment for age, sex, and comorbidities (adjusted HR, 0.75; 95% CI, 0.69-0.82). This effect was confirmed on a propensity-matched analysis, with an HR of 0.76 (95% CI, 0.69-0.85). Finally, these findings were robust to subanalyses that stratified patients by presenting symptoms and were more pronounced in symptomatic patients (adjusted HR, 0.69; 95% CI, 0.61-0.79) than in asymptomatic patients (adjusted HR, 0.80; 95% CI, 0.71-0.90). CONCLUSIONS: During the last 15 years, patients who underwent CEA in the Vascular Quality Initiative have a long-term survival advantage over those who underwent CAS in real-world practice. Despite no difference in long-term survival in randomized trials, our observational study demonstrated a survival benefit for CEA that did not diminish with risk adjustment.

Comparison of outcomes in women and men following carotid interventions in the Washington state's Vascular Interventional Surgical Care and Outcomes Assessment Program.

BACKGROUND: The benefit for carotid endarterectomy (CEA) to prevent a potential stroke has been shown to be less beneficial for women compared with men and the risk of carotid stenting (CAS) is higher in women than men. We hypothesized that a community-based Washington state registry data would also reveal increased morbidity and mortality for women undergoing carotid interventions. METHODS: Deidentified data for CEA and CAS between 2010 and 2015 were obtained from 19 hospitals participating in the Washington State Vascular-Interventional Surgical Care and Outcomes Assessment Program. Data analysis compared in-hospital composite outcome of stroke and mortality from CEA and CAS between women and men. RESULTS: Over the study period, 3704 individuals underwent CEA (n = 2759; 49.5% symptomatic) and CAS (n = 945; 60.9% symptomatic). Women accounted for 39.5% of the cohort. Women were slightly younger than men (70.0 ± 10.2 vs 71.0 ± 9.6 years respectively; P < .01), less likely to be smokers (70.1% vs 75.6%; P < .01), and less likely to have a diagnosis of coronary artery disease (32.9% vs 46.5%; P < .01). Fewer women underwent CEA for symptomatic carotid disease (46.1% vs 51.8%; P < .01). There were no statistically significant differences in the postoperative in-hospital stroke and mortality among women and men undergoing CEA (asymptomatic, 0.8% vs 1.4% [P = .36]; symptomatic, 1.8% vs 2.2% [P = .58]) and CAS (asymptomatic, 1.4% vs 2.2% [P = .56]; symptomatic, 4.6% vs 2.5% [P = .18]). Hospital duration of stay and discharge disposition were similar for women and men. A subanalysis of the octogenarian cohort undergoing CAS demonstrated a substantial increase in-hospital stroke and mortality among women and men (11.6% [CAS] vs 2.2% [CEA]; P = .024). CONCLUSIONS: In the Washington state Vascular-Interventional Surgical Care and Outcomes Assessment Program registry, hospital composite outcome of stroke and mortality following carotid interventions from 2010 to 2015 were noted to be similar for women and men. The notable exception to this finding was observed in subcohort of women undergoing CAS for symptomatic carotid disease at age 80 years or older. These findings should be taken into account when risk stratifying patients for carotid interventions.

Cost-effectiveness of low-dose rivaroxaban and aspirin versus aspirin alone in people with peripheral or carotid artery disease: An Australian healthcare perspective.

AIMS: Peripheral artery disease affects 1.2% of the population globally and is associated with an increased risk of atherothrombotic cardiovascular events, major adverse limb events and mortality. The Cardiovascular Outcomes for People Using Anti-coagulation Strategies (COMPASS) trial demonstrated positive results of rivaroxaban plus aspirin therapy compared to aspirin therapy alone in those with peripheral artery disease or carotid artery disease. We sought to estimate the cost-effectiveness from the Australian healthcare system perspective. METHODS AND RESULTS: A Markov model was developed to simulate the experiences of a hypothetical population of 1000 individuals with peripheral artery disease or carotid artery disease, profiled on the COMPASS trial, treated with rivaroxaban plus aspirin therapy versus aspirin therapy alone. With each annual cycle, individuals were at risk of having non-fatal cardiovascular disease events, major adverse limb events, or dying. Individuals were also at risk of non-fatal major bleeding. The model had a lifetime time horizon. Costs and utilities were sourced from the literature and discounted at 5.0% annually. Rivaroxaban plus aspirin therapy prevented 143 non-fatal cardiovascular disease events, 118 major adverse limb events and 10 deaths compared to aspirin therapy alone. Conversely, 156 additional major non-fatal bleeds were accrued. With an additional 256 quality-adjusted life years gained, at an additional cost of AUD$6,858,103, the incremental cost-effectiveness ratio was AUD$26,769 (discounted) per quality-adjusted life year gained, which is below Australia's arbitrary willingness to pay threshold of AUD$50,000. CONCLUSION: In those with peripheral artery disease or carotid artery disease, rivaroxaban plus aspirin therapy is effective and cost-effective in the prevention of recurrent cardiovascular disease compared to aspirin therapy alone.

Stroke and Cardiovascular Outcomes in Patients With Carotid Disease Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND: Stroke is a serious complication of both transcatheter aortic valve replacement (TAVR) and carotid artery disease (CD). The implications of CD in patients undergoing TAVR are unclear. METHODS AND RESULTS: The Society of Thoracic Surgeons and American College of Cardiology Transcatheter Valve Therapies Registry, consisting of data from consecutive US TAVR cases during the years 2013 to 2015, was linked to Medicare claims data to ascertain 30-day and 1-year cumulative incidence rates of stroke and all-cause mortality. We compared 30-day and 1-year stroke and mortality outcomes between patients with no-CD and patients with moderate, severe, and occlusive CD and adjusted for baseline covariates using proportional hazards models. Among 29 143 patients undergoing TAVR across 390 US sites, 22% had CD. Patients with CD had higher rates of prior hypertension, diabetes mellitus, stroke, and myocardial infarction. Observed in-hospital stroke rates were 2.0% among no-CD, 2.5% among moderate CD, 3.0% among severe CD, and 2.6% among occlusive CD. There was no association between the presence of CD and 30-day stroke (adjusted hazard ratio, 1.16; 95% confidence interval, 0.94-1.43) or mortality (adjusted hazard ratio, 1.10; 95% confidence interval, 0.95-1.28). There was no association between CD and 1-year stroke (adjusted hazard ratio, 1.03; 95% confidence interval, 0.86-1.24) or mortality (adjusted hazard ratio, 1.02; 95% confidence interval, 0.93-1.12). Furthermore, there was no significant risk-adjusted association between severity of CD and 30-day or 1-year stroke or mortality. CONCLUSIONS: CD is common among TAVR patients, present in 1 of 5. CD was not associated with an increased risk of stroke or mortality at 30 day or 1 year. Post-TAVR stroke seems to be because of mechanisms other than CD.

Racial and Socioeconomic Disparities After Carotid Procedures.

BACKGROUND: Race has been associated with inferior outcomes after multiple procedures, but the association of socioeconomic status with procedures for cerebrovascular disease is not well established. MATERIALS AND METHODS: Elective carotid artery stenting (CAS) and carotid endarterectomy (CEA) procedures were identified in the National Inpatient Sample, 2012 to 2014. Median household income was estimated from patient ZIP codes. Chi-square and multivariable logistic regression analysis evaluated outcomes, accounting for age, race, gender, comorbidities, procedure, income, insurance, and hospital characteristics. RESULTS: We identified 234 825 carotid procedures (205 835 CEA and 28 990 CAS). Blacks and Hispanics were more likely to be among the lowest quartile income patients (LQIPs) compared to whites (53.5% and 38.7% vs 27.0%, respectively; P < .0002). Compared to highest income quartile patients, LQIP had lower rates of private insurance (16.3% vs 22.0%) and higher Medicaid use (4.7% vs 2.0%; all P < .0002). Lowest quartile income patients were more likely to receive CAS (odds ratio [OR] = 1.32, 95% confidence interval [CI]: 1.27-1.37), as were blacks and Hispanics (OR = 1.09, 95% CI: 1.02-1.26; OR = 1.31, 95% CI: 1.24-1.40, respectively). In multivariable regression, postoperative stroke was associated with LQIP, black race, and Hispanic ethnicity (OR = 1.16, 95% CI: 1.06-1.28; OR = 1.52, 95% CI: 1.33-1.73; OR = 1.43, 95% CI: 1.24-1.64, respectively). Subgroup analysis demonstrated that whites also had higher odds of stroke in the lower income quartile (OR = 1.2, 95% CI: 1.1-1.4). Mortality was associated with LQIP (OR = 1.6, 95% CI: 1.2-2.1), black race (OR = 1.8, 95% CI: 1.4-2.5), and CAS (OR = 1.3, 95% CI: 1.1-1.6). Length of stay in the lowest income quartile was longer than in patients with the highest income ( P < .0001). CONCLUSIONS: Race was associated with increased hospital mortality, postoperative stroke, and overall complications after carotid procedures. Lower income was significantly associated with increased stroke and mortality irrespective of race. Disparate utilization and outcomes for carotid procedures are multifactorial. Efforts to reduce disparities will need to focus on race and other socioeconomic factors.

The impact of race on outcomes after carotid endarterectomy in the United States.

OBJECTIVE: Black patients undergoing carotid endarterectomy (CEA) in the United States are more often symptomatic at presentation and have more comorbidities compared with white patients. However, the impact of race on outcomes after CEA is largely unknown. METHODS: We identified CEA patients in the Vascular Quality Initiative registry (2012-2017) and compared them by race (black vs white). All other nonwhite races (891 [1.4%]) and Hispanics (2222 [3.4%]) were excluded. We used multilevel logistic regression to account for differences in demographics and comorbidities. We assessed long-term survival using multivariable Cox regression. The primary outcome was perioperative stroke/death, with long-term survival as a secondary outcome. RESULTS: We included 57,622 CEA patients; 2909 (5.0%) were black, of whom 983 (34%) were symptomatic. Of the 54,713 white patients, 16,132 (30%) were symptomatic. Black patients, compared with white patients, had a higher vascular disease burden and were less likely to be operated on in a high-volume hospital or by a high-volume surgeon. In addition, black symptomatic patients, compared with white symptomatic patients, were more often operated on <2 weeks after the index neurologic symptom (47% vs 40%; P < .001). Perioperative stroke/death was comparable between black and white patients (symptomatic, 2.8% vs 2.2% [P = .2]; asymptomatic, 1.6% vs 1.3% [P = .2]), as was unadjusted survival at 3 years (93% vs 93%; P = .7). However, after adjustment, black patients did experience better long-term survival compared with white patients (hazard ratio, 0.8; 95% confidence interval, 0.7-0.9; P = .01). On multilevel logistic regression, race was not associated with perioperative stroke/death (odds ratio, 1.0; 95% confidence interval, 0.8-1.3; P = .98). CONCLUSIONS: Despite the greater prevalence of vascular risk factors in black patients and racial inequalities in surgical treatment, rates of perioperative stroke/death and unadjusted survival were similar between white and black patients. Moreover, black patients experienced better adjusted long-term survival after CEA.

Factors that Predict Failure to Meet Merit-Based Incentive Payment System Quality Measures for Asymptomatic Carotid Endarterectomy.

BACKGROUND: The Physician Quality Reporting System (PQRS) created by the Centers for Medicare and Medicaid Services financially penalizes providers who fail to meet expected quality of care measures. The purpose of this study is to evaluate the factors that predict failure to meet PQRS measures for carotid endarterectomy (CEA). METHODS: PQRS measure 260 (discharge by postoperative day 2 following CEA in asymptomatic patients) and 346 (rate of postoperative stroke or death following CEA in asymptomatic patients) were evaluated using hospital records from the state of Florida from 2008 to 2012. The impact of demographics, comorbidities, hospital factors, admission variables, and individual practitioner data upon timely discharge, and postoperative stroke and death. Odds ratios, 95% confidence intervals, and significance (P < 0.05) were determined through the development of a logistic regression model. Surgeons were identified by national provider identifier number, and practitioner data obtained from the American Medical Association Physician Masterfile. RESULTS: A total of 34,235 patient records and 701 providers were identified over the 5-year period. Significant negative predictors for PQRS measure 260 included weekend admission (odds ratio [OR], 2.9), Medicaid (OR, 2.4), surgeon historical postoperative stroke rate >2.0% (OR, 1.7), African-American race (OR, 2.0), and female gender (OR, 1.3). The presence of any of these factors was associated with a 13.5% rate of failure. The most significant negative predictor for PQRS measure 346 was surgeon postoperative stroke rate >2.0% (OR, 6.2 for stroke and OR, 29.0 for death). Surgeons in this underperforming group had worse outcomes compared to their peers despite having patients with fewer risk factors for poor outcomes. Surgeon specialty, board certification, and case volume do not impact either PQRS measures. CONCLUSIONS: Selected groups of patients and surgeons with a disproportionately high rate of postoperative stroke are at risk of failing to meet PQRS pay for performance quality measures. Awareness of these risk factors may help mitigate and minimize the risk of adversely impacting the value stream. Further evaluation of the causative factors that lead to surgeon underperformance could help to improve the quality of care.

Risk-adjusted hospital outcomes in elective carotid artery surgery in patients with Medicare.

BACKGROUND: The risk-adjusted outcomes by hospital of elective carotid endarterectomy that is inclusive of inpatient and 90-day postdischarge adverse outcomes have not been studied. METHODS: We studied Medicare inpatients to identify hospitals with 25 or more qualifying carotid endarterectomy cases between 2012-2014. Risk-adjusted prediction models were designed for adverse outcomes of inpatient deaths, 3-sigma prolonged duration-of-stay outliers, 90-day postdischarge deaths without readmission, and 90-day postdischarge associated readmissions. Standard deviations of predicted overall adverse outcomes were computed for each hospital. Hospital-specific z scores and risk-adjusted adverse outcomes were calculated. RESULTS: There were 77,086 carotid endarterectomy patients from 960 hospitals complicated by 191 inpatient deaths (0.25%), 4,436 prolonged duration of stay (5.8%), 457 90-day postdischarge deaths (0.6%), and 7,956 90-day postdischarge associated readmissions (10.3%). In the 90-day postdischarge associated readmission patients, an additional 561 patients died after readmission, for total deaths of 1,209 (1.6%) for the study period, and 11,928 (15.5%) patients had one or more adverse outcomes. There were 29 best-performing hospitals (3.0%) with z scores of -2.0 or less (P < .05) with a median rate of risk-adjusted adverse outcomes of 7.1%. A total of 61 suboptimal performers (6.3%) had z scores of +2.0 or greater (P < .05) with a median rate of risk-adjusted adverse outcome rate of 26.4%. CONCLUSION: Hospital risk-adjusted adverse outcome rates for carotid endarterectomy are highly variable. Comparisons of hospital performance define the opportunity for improvement.

Comparison of 30-day readmission rates and risk factors between carotid artery stenting and endarterectomy.

OBJECTIVE: The aim of this study was to analyze the rates, reasons, and risk factors of 30-day readmission, both planned and unplanned, after carotid revascularization as well as to evaluate major outcomes associated with those readmissions. METHODS: Using the Premier Healthcare database, we retrospectively identified patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS) between 2009 and 2015. The primary outcome was 30-day all-cause readmission. Secondary outcomes included mortality and overall cost associated with readmissions. Univariate and multivariate analyses were used and further validated using coarsened exact matching on baseline differences between CEA and CAS patients. RESULTS: A total of 95,687 patients underwent carotid revascularization, 13.5% of whom underwent CAS. Crude 30-day readmission rates were 6.5% after CEA vs 6.1% after CAS (P = .10). Stroke, bleeding, pneumonia, and respiratory failure were the most common reasons for readmission after both CEA and CAS (6.7% vs 8.3%, 6.9% vs 5.3%, 3.4% vs 2.4%, and 4.4% vs 3.9%; all P > .05). Myocardial infarction and wound complications were more likely to be an indication for readmission after CEA (4.1% vs 2.5% and 4.1% vs 1.5%, respectively; P < .05). On the other hand, readmissions due to vascular or stent-related complications were more likely after CAS compared with CEA (5.8% vs 3.8%; P = .003). On multivariate analysis, CEA was found to be associated with 41% higher odds of readmission than CAS (adjusted odds ratio, 1.41; 95% confidence interval, 1.29-1.54; P < .001). Age, female gender, emergency/urgent procedures, concomitant cardiac procedures, rural hospitals, and Midwest region were significantly associated with 30-day readmission. Other risk factors included major preoperative comorbidities (diabetes, congestive heart failure, renal disease, chronic obstructive pulmonary disease, peripheral vascular disease, and history of cancer) as well as the occurrence of postoperative stroke and renal complications during the index admission and nonhome discharge. Coarsened exact matching between CEA and CAS patients also yielded higher adjusted rates of readmission after CEA (6.2% vs 4.9%; P < .001). On the other hand, patients readmitted after CAS had a longer length of hospital stay (5 days vs 4 days; P = .001), increased readmission mortality (6.2% vs 2.8%; P < .001), and higher rehospitalization costs ($8903 vs $7629; P = .01) compared with those readmitted after CEA. CONCLUSIONS: Our results show that CAS is associated with lower 30-day readmission rates compared with CEA. However, CAS readmissions are more complex and are associated with higher mortality and costs. We have also identified patients who are at high risk of readmissions, which can help focus attention on interventions that can improve the management of these patients and reduce readmission rates.

A contemporary evaluation of carotid endarterectomy outcomes in patients with chronic kidney disease in the United States.

Objectives Chronic kidney disease (CKD) has been identified as a significant risk factor for poor post-surgical outcomes. This study was designed to provide a contemporary analysis of carotid endarterectomy (CEA) outcomes in patients with CKD, end-stage renal disease (ESRD), and normal renal function (NF). Methods The Nationwide Inpatient Sample data 2006-2012 was queried to select patients aging 40 years old and above who underwent CEA during two days after admission and had a diagnosis of ESRD on long-term hemodialysis, patients with non-dialysis-dependent CKD, or NF. Patients with acute renal failure were excluded. We subsequently compared procedure outcomes and hospital resource utilization in these patients. Results Totally 573,723 CEA procedures were estimated: 4801 (ESRD)' 32,988 (CKD)' and 535,934 (NF). Mean age was 71.0 years, 57.7% were males, and 73.7% were white. Overall hospital mortality was 0.20%: 0.69% (ESRD), 0.35% (CKD), and 0.19% (NF), p < 0.0005 between groups. The overall stroke rate was 1.6%: 1.8% (ESRD), 2.0% (CKD), and 1.6% (NF). Comparing NF to CKD there was a significant difference: p < 0.0001. For CKD patients, compared to NF patients, there was an increased risk in cardiac complications (odds ratio = 1.2; 95% CI 1.15-1.32), respiratory complications (odds ratio = 1.2; 95% CI 1.15-1.32), and stroke (odds ratio = 1.1; 95% CI 1.04-1.23). For ESRD patients compared to NF patients there was an increased risk in respiratory complications (odds ratio = 1.3; 95% CI 1.08-1.47) and sepsis (odds ratio = 4.4; 95% CI 3.23-5.94). Mean length of stay and cost were: 2.8 d and $13,903 (ESRD), 2.2 d and $12,057 (CKD), and 1.8 d and $10,130 (NF), all p < 0.0001. Conclusions Patients with ESRD undergoing CEA had an increased risk of respiratory and septic complications, but not a higher risk of stroke compared to patients with normal renal function. The greatest risks of postoperative stroke, respiratory, and cardiac complications were found in patients with CKD. A diagnosis of ESRD and CKD were both found to significantly increase hospital mortality, length of stay and cost. Where clinicians typically consider ESRD patients the highest risk for CEA, further consideration should be given to patients with CKD not yet on dialysis as they had the higher risk of cardiac complications and stroke compared to the others evaluated.

Predictors of poor outcome after carotid intervention.

BACKGROUND: A variety of patient factors are known to adversely impact outcomes after carotid endarterectomy (CEA) or carotid artery stenting (CAS). However, their specific impact on complications and mortality and how they differ between CEA and CAS is unknown. The purpose of this study is to identify patient and hospital factors that adversely impact outcomes. METHODS: Patients who underwent CEA or CAS between 1998 and 2012 (N = 1,756,445) were identified using the Agency for Healthcare Research and Quality National Inpatient Sample and State Ambulatory Services Databases. A multivariate analysis was completed to evaluate the impact of demographics, patient factors, type of symptoms (transient ischemic attack or cerebrovascular accident), volume of cases (3 per year vs 1-2 interventions), and interventions upon outcomes, perioperative complications (stroke, myocardial infarction, and bleeding), duration of stay, inpatient mortality, and cost. Significant factors were then used as part of a multivariate regression analysis to determine odds ratios. A subgroup analysis using propensity matching evaluating 1:1 risk-matched asymptomatic and symptomatic patients was completed. Patient cohorts were matched on the basis of Charlson scores. RESULTS: Over the study period a total of 1,583,614 asymptomatic CEA, 7317 asymptomatic CAS, 162,362 symptomatic CEA, and 3149 symptomatic CAS patients were included. Symptomatic disease portends a worse outlook after either CEA or CAS. Costs of the procedure increased with complications with stroke adding the most significant cost burden. For risk-matched asymptomatic and symptomatic patients, female gender (P < .001) and performing one or two cases per year (P < .05) were associated with higher cerebrovascular accident risk. In asymptomatic and symptomatic patients, predictors of myocardial infarction included congestive heart failure (P < .001) and peripheral artery disease (P < .05) and predictors of bleeding included peripheral artery disease (P < .05) and chronic obstructive pulmonary disease (P < .01) for symptomatic patients only. For both asymptomatic and symptomatic patients, predictors of mortality included female gender (P < .001) and performing one or two cases per year (P < .01). Female gender was one of the strongest overall predictors of adverse outcome after CAS (odds ratio, 21.39 for death; P < .001). Low volume (<3 cases per year per practitioner) is a predictor of adverse outcome after CAS only. CONCLUSIONS: Higher rates of postoperative stroke and inpatient mortality for women undergoing CAS is an unexpected finding, and may indicate that this population is vulnerable to complications after endovascular management. Low volume is a predictor of complications and subsequent mortality primarily for CAS. Patients who undergo CEA continue to have superior outcomes compared with matched cohorts who undergo CAS.

Clinical Relevance of Cardiac Troponin Assessment in Patients Undergoing Carotid Endarterectomy.

OBJECTIVE: Myocardial infarction (MI) is a frequent complication of carotid endarterectomy (CEA), yet most events are silent. Routine post-operative monitoring of cardiac troponin was implemented to facilitate timely recognition of MI and stratify high risk patients. The aim was to evaluate the incidence of troponin elevation after CEA and its association with adverse cardiovascular events. METHODS: This analysis included patients ≥60 years old who underwent CEA, whose troponin-I levels were routinely monitored post-operatively and were included in a cohort study that assessed clinical outcomes. A clinical troponin cutoff of 60 ng/L was used. The primary endpoint was the composite of MI, stroke, and cardiovascular death. Secondary endpoints were MI, stroke, coronary intervention, cardiovascular death, and all cause death. RESULTS: 225 consecutive patients were included in the analysis. Troponin elevation occurred in 34 patients (15%) and a post-operative MI was diagnosed in eight patients. After a median follow up of 1.8 years (IQR 1.0-2.6), the primary endpoint occurred in 29% of patients with troponin elevation versus 6.3% without (HR 5.6, 95% CI 2.4-13), MI in 24% versus 1.6% (HR 18.0, 95% CI 4.7-68), stroke in 5.9% versus 4.2% (HR 1.4, 95% CI 0.3-6.7), coronary intervention in 5.9% versus 2.6% (HR 2.7, 95% CI 0.5-14), cardiovascular death in 5.9% versus 0.5% (HR 11.8, 95% CI 1.1-131), and all cause death in 15% versus 5.8% (HR 3.0, 95% CI 1.0-8.7), respectively. Incidences of the primary endpoint and all cause mortality in patients with a post-operative MI versus "troponin only" were 25% versus 7.7% and 25% versus 12%, respectively. CONCLUSION: Troponin elevation after CEA occurred in 15% of patients. The incidence of adverse cardiovascular events was significantly higher in patients with troponin elevation, which was mainly attributable to silent non-ST segment elevation MIs that occurred in the early post-operative phase.

Medicare inpatient and 90-day postdischarge adverse outcomes in carotid artery surgery.

BACKGROUND: Longitudinal, risk-adjusted measurement of outcomes of carotid artery (CA) surgery is necessary for the evaluation of quality performance and for the assessment of strategies of quality improvement. METHODS: Patients from quality coding hospitals who underwent CA surgery and met procedural and diagnostic coding requirements in the Medicare Inpatient Limited Data Set from 2009 to 2011 were used to design logistic prediction models for the Adverse Outcomes (AOs) of inpatient deaths, 3-sigma prolonged length-of-stay outliers (prLOS) among live discharges, 90-day post-discharge deaths without readmission (PD-90), and 90-day post-discharge readmissions (ReAdm-90). RESULTS: A total of 653 quality coding hospitals had 54,183 CA surgery cases. There were 122 inpatient deaths (0.23%) and 3,337 (6.2%) prLOS. After discharge, there were 258 patients that were PD-90 and 9,804 patients (18.1 % of live discharges) were readmitted. Among all readmissions, 1,592 (13.3%) were judged to be totally unrelated to the index operation. A total of 495 patients died during readmission to the hospital. The rate of total adverse outcome was 22.6% with all ReAdm-90 cases counted. CONCLUSION: In CA surgery, more AOs occur in the 90 days after discharge than during the inpatient period of care. ReAdm-90 remains the major cause for AOs and represents the greatest opportunity for improvement in the care of CA surgery patients.

Preoperative frailty Risk Analysis Index to stratify patients undergoing carotid endarterectomy.

OBJECTIVE: Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains problematic. Preoperative variables correlate with increased morbidity and mortality, yet no easily implemented tool exists to stratify patients. We determined the relationship between our fully implemented frailty-based bedside Risk Analysis Index (RAI) and complications after CEA. METHODS: Patients undergoing CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2011 were included. Variables of frailty RAI were matched to preoperative NSQIP variables, and outcomes including stroke, mortality, myocardial infarction (MI), and length of stay were analyzed. We further analyzed patients who were symptomatic and asymptomatic before CEA. RESULTS: With use of the NSQIP database, 44,832 patients undergoing CEA were analyzed (17,696 [39.5%] symptomatic; 27,136 [60.5%] asymptomatic). Increasing frailty RAI score correlated with increasing stroke, death, and MI (P < .0001) as well as with length of stay. RAI demonstrated increasing risk of stroke and death on the basis of risk stratification (low risk [0-10], 2.1%; high risk [>10], 5.0%). Among patients undergoing CEA, 88% scored low (<10) on the RAI. In symptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 2.9%, whereas if the RAI score is 11 to 15, it is 5.0%; 16 to 20, 6.9%; and >21, 8.6%. In asymptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 1.6%, whereas if the RAI score is 11 to 15, it is 2.9%; 16 to 20, 5.2%; and >21, 6.2%. CONCLUSIONS: Frailty is a predictor of increased stroke, mortality, MI, and length of stay after CEA. An easily implemented RAI holds the potential to identify a limited subset of patients who are at higher risk for postoperative complications and may not benefit from CEA.

Practice patterns of carotid endarterectomy as performed by different surgical specialties at a single institution and the effect on perioperative stroke and cost of preoperative imaging.

BACKGROUND: Carotid endarterectomy (CEA) is currently performed by various surgical specialties with varying outcomes. This study analyzes different surgical practice patterns and their effect on perioperative stroke and cost. METHODS: This is a retrospective analysis of prospectively collected data of 1000 consecutive CEAs performed at our institution by three different specialties: general surgeons (GS), cardiothoracic surgeons (CTS), and vascular surgeons (VS). RESULTS: VS did 474 CEAs, CTS did 404, and GS did 122. VS tended to operate more often on symptomatic patients than CTS and GS: 40% vs 23% and 31%, respectively (P < .0001). Preoperative workups were significantly different between specialties: duplex ultrasound (DUS) only in 66%, 30%, and 18%; DUS and computed tomography angiography in 27%, 35%, and 29%; and DUS and magnetic resonance angiography in 6%, 35%, and 52% for VS, CTS, and GS, respectively (P < .001). The mean preoperative carotid stenosis was not significantly different between the specialties. The mean heparin dosage was 5168, 7522, and 5331 units (P = .0001) and protamine was used in 0.2%, 19%, and 8% (P < .0001) for VS, CTS, and GS, respectively. VS more often used postoperative drains; however, no association was found between heparin dosage, protamine, and drain use and postoperative bleeding. Patching was used in 99%, 93%, and 76% (P < .0001) for VS, CTS, and GS, respectively. Bovine pericardial patches were used more often by CTS and ACUSEAL (Gore-Tex; W. L. Gore and Associates, Flagstaff, Ariz) patches were used more often by GS (P < .0001). The perioperative stroke/death rates were 1.3% for VS and 3.1% for CTS and GS combined (P = .055); and were 0.7% for VS and 3% for CTS and GS combined for asymptomatic patients (P < .034). Perioperative stroke rates for patients who had preoperative DUS only were 0.9% vs 3.3% for patients who had extra imaging (computed tomography angiography/magnetic resonance angiography; P = .009); and were 0.9% vs 3% for asymptomatic patients (P = .05). When applying hospital billing charges for preoperative imaging workups (cost of DUS only vs DUS and other imaging), the VS practice pattern would have saved $1180 per CEA over CTS and GS practice patterns; a total savings of $1,180,000 in this series. CONCLUSIONS: CEA practice patterns differ between specialties. Although the cost was higher for non-VS practices, the perioperative stroke/death rate was somewhat higher. Therefore, educating physicians who perform CEAs on cost-saving measures may be appropriate.

National experience with extracranial carotid artery aneurysms: epidemiology, surgical treatment strategy, and treatment outcome.

OBJECTIVE: Extracranial carotid artery aneurysms (CAAs) are rare but confer risk of stroke, rupture, and local symptoms. Few cases have been reported, even from large centers, and therefore knowledge of the disease is limited. The purpose of this study was to review epidemiology, surgical treatment, and outcomes of CAAs in a nationwide setting using the Swedish National Registry for Vascular Surgery (Swedvasc). METHODS: Data on all surgical interventions for CAAs from January 1997 to December 2011 were retrieved from the Swedvasc registry. Additional clinical information was collected from hospital records. RESULTS: A total of 48 cases of CAAs were identified. The cause was atherosclerosis in 34 cases, infection in 2, and pseudoaneurysm in 12. The most common presentation was a pulsatile mass with or without local symptoms. Aneurysms isolated to the internal carotid artery predominated. Resection with end-to-end anastomosis was the most common technique used for treatment. Among true aneurysms, 24% had a known synchronous aneurysm elsewhere. Stroke-free survival (n = 48) was 90% after 30 days and 85% after 1 year. A total of 12.5% patients experienced permanent cranial nerve injury and 33% experienced any complication. CONCLUSIONS: CAAs are rare entities in vascular surgery. In terms of stroke-free survival, the Swedish national results approach reports from large volume centers. The relatively high risk for permanent cranial nerve injury advocates caution when performing surgery on CAAs.