Cost-effectiveness of transcarotid artery revascularization versus carotid endarterectomy.

OBJECTIVE: Recent studies have demonstrated that transcarotid artery revascularization (TCAR) has comparable outcomes to the surgical gold standard, carotid endarterectomy (CEA). However, few studies have analyzed the cost of TCAR, and no study has evaluated its cost-effectiveness. The purpose of this study is to conduct a cost-effectiveness analysis comparing TCAR with CEA for carotid artery stenosis. METHODS: We built a Markov microsimulation using transition probabilities and utilities from existing literature for symptomatic patients undergoing TCAR or CEA. Costs were derived from literature then converted to 2019 dollars. The model included six health states with monthly cycle lengths: surgery, death, alive after surgery, alive after myocardial infarction, alive after stroke, and alive after stroke and death. Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratio (ICER) were analyzed over a 5-year period. One-way sensitivity and probabilistic sensitivity analyses were conducted to study the impact of parameter variability on cost effectiveness. RESULTS: For symptomatic patients, CEA cost $7821 for 2.85 QALYs, whereas TCAR cost $19154 for 2.92 QALYs, leading to an ICER of $152,229 per QALY gained in the TCAR arm. Sensitivity analysis demonstrated that our model was most sensitive to probability of restenosis, costs of TCAR, and costs of CEA. Probabilistic sensitivity analysis demonstrated TCAR would be considered cost-effective in 49% of iterations. CONCLUSIONS: This study found that, although 5-year costs for TCAR were greater than CEA, TCAR afforded greater QALYs than CEA. TCAR became cost-effective at 6 years of follow-up.

Epidemiological Analysis of 37,424 Carotid Artery Stenosis Intervention Procedures During 11 Years in the Public Health System in Brazil: Stenting has Been More Common Than Endarterectomy.

BACKGROUND: Stroke is a leading cause of death worldwide, with carotid atherosclerosis accounting for 10-20% of cases. In Brazil, the Public Health System provides care for roughly two-thirds of the population. No studies, however, have analysed large-scale results of carotid bifurcation surgery in Brazil. METHODS: This study aimed to describe rates of carotid artery stenting (CAS) and carotid endarterectomy (CEA) performed between 2008 and 2019 in the country through web scraping of publicly available databases. RESULTS: Between 2008 and 2019, 37,424 carotid bifurcation revascularization procedures were performed, of which 22,578 were CAS (60.34%) and 14,846 (39.66%) were CEA. There were 620 in-hospital deaths (1.66%), 336 after CAS (1.48%) and 284 after CEA (1.92%) (P = 0.032). Governmental reimbursement was US$ 77,216,298.85 (79.31% of all reimbursement) for CAS procedures and US$ 20,143,009.63 (20.69%) for CEA procedures. The average cost per procedure for CAS (US$ 3,062.98) was higher than that for CEA (US$ 1,430.33) (P = 0.008). CONCLUSIONS: In Brazil, the frequency of CAS largely surpassed that of CEA. In-hospital mortality rates of CAS were significantly lower than those of CEA, although both had mortality rates within the acceptable rates as dictated by literature. The cost of CAS, however, was significantly higher. This is a pioneering analysis of carotid artery disease management in Brazil that provides, for the first time, preliminary insight into the fact that the low adoption of CEA in the country is in opposition to countries where utilization rates are higher for CEA than for CAS.

Cost-effectiveness of Carotid Surgery.

BACKGROUND: The purpose of this study is to determinate the cost-effectiveness of carotid endarterectomy (CEA) versus transfemoral stenting (TFS) and transcervical stenting (TCS) in a short- and long-term basis in symptomatic and asymptomatic patients. METHODS: From January 2003 to December 2014, patients from the vascular department, with symptomatic or asymptomatic carotid stenosis, who were clinically and anatomically suitable for TFS, TCS, or CEA, were included. Prospective cost data for each individual procedure and complication during follow-up were obtained from the diagnosis-related group. The quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios were estimated. Analysis of data was by treatment received. All statistical tests were two-sided. The significance level was 5%. RESULTS: A total of 349 patients were enrolled: 61 for CEA (17.5%), 159 for TFS (45.5%), and 129 for TCS (37%). A total of 220 (63%) patients were symptomatic and 129 (37%) were asymptomatic. The median procedural cost and overall cost were lower on CEA (5499€ and 5595€, respectively). However, QALYs, for symptomatic patients, were better on TCS (7.3), whereas for asymptomatic patients, QALYs were better on CEA (9.6). Cost-effectiveness for symptomatic patients was better with TCS (803€/QALY), and for asymptomatic patients, it was with CEA (654€/QALY). CONCLUSIONS: TFS and TCS were associated with clinical outcomes equivalent to CEA on both symptomatic and asymptomatic patients. Cost-effectiveness ratios for symptomatic patients were better on TCS, whereas the CEA showed the best results in asymptomatic patients.

Association between Medicare high-risk criteria and outcomes after carotid revascularization procedures.

BACKGROUND: The U.S. Centers for Medicare and Medicaid Services (CMS) has defined a set of high-risk criteria to help define patients who are appropriate for carotid artery stenting (CAS), but these criteria have never been validated. We aimed to validate the CMS high-risk criteria in a nationally representative cohort of patients undergoing CAS and carotid endarterectomy (CEA). METHODS: All patients undergoing CAS (with embolic protection) or CEA in the Vascular Quality Initiative (VQI) database (2013-2016) were included. Patients were stratified as being at normal risk (Nr) or high risk (Hr) for undergoing CEA on the basis of CMS criteria. Thirty-day and 2-year stroke outcomes were compared for CAS vs CEA in both the Nr and Hr groups using 1:1 coarsened exact matching and multivariable Cox proportional hazards modeling. RESULTS: A total of 51,942 patients (CAS, 7030; CEA, 44,912) underwent carotid revascularization during the study period. Thirty-day (Nr, 1.7% vs 1.0%; Hr, 2.5% vs 1.4%) and 2-year (Nr, 1.9% vs 1.0%; Hr, 2.4% vs 1.3%) stroke occurred more frequently after CAS vs CEA on crude analysis (P < .001). After matching 2920 pairs of patients on 18 preoperative variables, the risk of 30-day and 2-year stroke remained higher after CAS in the Hr group (30-day risk: hazard ratio [HR], 1.90; 95% confidence interval [CI], 1.26-2.85; 2-year risk: HR, 1.65; 95% CI, 1.05-2.60) but was similar for CAS vs CEA in the Nr group (30-day risk: HR, 0.97; 95% CI, 0.48-1.95; 2-year risk: HR, 1.49; 95% CI, 0.76-2.90). CONCLUSIONS: These data suggest that the utility of CAS in Nr patients may be underappreciated, whereas the potential benefit of CAS in Hr patients may be overestimated. Re-evaluation of the criteria for identifying patients at high risk for CEA and the national guidelines on the indications for CAS is strongly indicated.

Examining variation in Medicare payments and drivers of cost for carotid endarterectomy.

BACKGROUND: There is a growing interest in providing high quality and low-cost care to Americans. A pursuit exists to measure not only how well hospitals are performing but also at what cost. We examined the variation in costs associated with carotid endarterectomy (CEA), to determine which components contribute to the variation and what drives increased payments. MATERIALS AND METHODS: Patients undergoing CEA between 2009 and 2012 were identified in the Medicare provider and analysis review database. Hospital quintiles of cost were generated and variation examined. Multivariable logistic regression was performed to identify independent predictors of high-payment hospitals for both asymptomatic and symptomatic patients undergoing CEA. RESULTS: A total of 264,018 CEAs were performed between 2009 and 2012; 250,317 were performed in asymptomatic patients in 2302 hospitals and 13,701 in symptomatic patients in 1851 hospitals. Higher payment hospitals had a higher percentage of nonwhite patients and comorbidity burden. The largest contributors to variation in overall payments were diagnosis-related groups, postdischarge, and readmission payments. After accounting for clustering at the hospital level, independent predictors of high-payment hospitals for all patients were postoperative stroke, length of stay, and readmission ,whereas in the symptomatic group, additional drivers included yearly volume and serious complications. CONCLUSIONS: CEA Medicare payments vary nationwide with diagnosis-related group, readmission, and postdischarge payments being the largest contributors to overall payment variation. In addition, stroke, length of stay, and readmission were the only independent predictors of high payment for all patients undergoing CEA.

Clinical Effect and Cost-Effectiveness of Screening for Asymptomatic Carotid Stenosis: A Markov Model.

OBJECTIVE/BACKGROUND: The cost-effectiveness of screening depends on the cost of screening, prevalence of asymptomatic carotid artery stenosis (ACAS), and the potential effect of medical intervention in reducing the risk of stroke. The aim of the study was to determine the threshold values for these parameters in order for screening for ACAS to be cost-effective. METHODS: The clinical effect and cost-effectiveness of ultrasound screening for ACAS with subsequent initiation of preventive therapy versus not screening was assessed in a Markov model with a lifetime perspective. Key parameters, including stroke risk, all cause mortality, and costs, were based on contemporary published data, population statistics, and data from an ongoing screening program in Uppsala county (population 300,000), Sweden. Prevalence of ACAS (2%) and the rate of best medical treatment (BMT; 40%) were based on data from a male Swedish population recently screened for ACAS. The required stroke risk reduction from BMT, incremental cost-efficiency ratio (ICER), absolute risk reduction for stroke (ARR), and number needed to screen (NNS) were calculated. RESULTS: Screening was cost-effective at an ICER of €5744 per incremental quality adjusted life year (QALY) gained. ARR was 135 per 100,000 screened, NNS was 741, and QALYs gained were 6700 per 100,000 invited. At a willingness to pay (WTP) threshold of €50,000 per QALY the minimum required stroke risk reduction from BMT was 22%. The assumed degree of stroke risk reduction was the most important determinant of cost-efficiency. CONCLUSION: A moderate (22%) reduction in the risk of stroke was required for an ACAS screening strategy to be cost-effective at a WTP of €50,000/QALY. Targeting populations with a higher prevalence of ACAS could further improve cost-efficiency.

Carotid occlusion is associated with more frequent neurovascular events than moderately severe carotid stenosis.

OBJECTIVE: Asymptomatic internal carotid artery occlusion (CO) presents a clinical dilemma, and presently, the natural history, stroke risk, and optimal management remain ill defined. This study compared outcomes, including neurovascular events (NVEs) and health care costs, between patients with CO and patients with asymptomatic carotid artery stenosis (CS). METHODS: A prospectively maintained database was queried to identify patients with CO and CS with at least >50% carotid stenosis by duplex. We identified and reviewed 622 consecutive patients with asymptomatic carotid artery disease at one academic medical center between 2011 and 2013. Patients with CO (n = 97) were identified and propensity matched by age and gender in a 1:2 ratio with CS patients (n = 194) for further analyses. Univariate and multivariate models were used to analyze baseline characteristics, clinical variables, and 1-year follow-up data from the date of diagnosis. Multivariate analysis was performed by multiple linear regression modeling. Institutional Review Board approval was obtained. RESULTS: Follow-up data were available for 99% of matched patients. CO patients were younger (72 vs 75 years; P < .01) and more likely male (67% vs 53%; P = .01) compared with CS patients. After propensity matching, baseline characteristics were similar between groups, with a trend toward higher use of statin therapy among patients with CO. Antiplatelet therapy was used in 79% of patients with CS and in 74% of patients with CO (P = .45). The rate of NVE among CO patients was higher than among CS patients at 1 year of follow-up (14% vs 7%; P = .03). Among those with NVE, neither antiplatelet therapy (64% vs 77%; P = .49) nor statin therapy (86% vs 77%; P = .58) appeared to have a significant effect. Health care costs ($14,361 vs $12,142; P = .44) and hospital admission rate (63% vs 71%; P = .18) were similar between groups. Not surprisingly, the rate of vascular procedures was higher in the CS group (55% vs 27%; P = .04). CONCLUSIONS: Patients with asymptomatic CO experience more NVEs compared with similar patients with moderately severe CS. Further study of preventative strategies, including intensity of medical therapy, is warranted.

Fixed and variable cost of carotid endarterectomy and stenting in the United States: A comparative study.

OBJECTIVE: Despite multiple landmark clinical trials, little data exists on real-world cost of carotid artery stenting (CAS) and carotid endarterectomy (CEA) to the United States healthcare system. We aim to study differences in actual hospitalization cost between patients who underwent CAS vs CEA in a nationally representative database. METHODS: We studied hospital discharge and billing records of all patients, in the Premier Perspective Database, who underwent CEA or CAS between the third quarter of 2009 and the first quarter of 2015. Nearest-neighbor 1:1 propensity score matching was performed, to account for differences in patient and hospital characteristics as well as clinical comorbidities of patients who underwent both procedures, for both symptomatic and asymptomatic cohorts using 32 variables. Pearson χ2, Student t-test, and nonparametric K-sample equality-of-medians tests were used to analyze the data, as appropriate. The primary outcome was total in-hospital cost, including fixed (administrative, capital and utilities) and variable costs (labor and supply). Cost data were presented as medians, inflation-adjusted for 2015 U.S. dollar and rounded to the nearest dollar. RESULTS: A total of 115,548 procedures were identified. The mean age was 71 and 69 years; 58% and 57% were male patients; and 81% and 77% were white among asymptomatic and symptomatic patients, respectively. After propensity score matching, 25,812 asymptomatic (12,906 CEA and 12,906 CAS) and 3864 symptomatic (1932 CEA and 1932 CAS) patients were included. Total hospitalization cost per CAS was 40% ($11,814 vs $8378; P < .001) and 37% ($19,426 vs $14,190; P < .001) higher than CEA among asymptomatic and symptomatic patients, respectively. Patients who underwent CAS incurred significantly higher total hospitalization cost despite stratifying by type of cost (fixed and variable), U.S. census regions and symptomatic status. Moreover, asymptomatic patients who underwent CAS performed by any surgical specialty incurred an average of $2717 to $4918 higher total hospitalization cost compared with patients who underwent CEA (all P < 001). Among symptomatic patients, those who underwent CAS performed by vascular, cardiac, and neurologic surgeons, incurred $2108 ($16,114 vs $14,006; P = .006), $7055 ($17,351 vs $10,296; P = .023) and $6479 ($27,290 vs $20,811; P = .002) higher total hospitalization cost compared with patients who underwent CEA, respectively. CONCLUSIONS: The total hospitalization cost incurred by patients who underwent CAS was significantly higher than for those who underwent CEA, despite matching cohort based on patient and hospital characteristics, and stratifying by symptomatic status, type of cost, hospital region, and surgeon specialty. Our findings could provide additional important information giving the ongoing controversy regarding the appropriate indication for CAS.

Investigation into drivers of cost of stenting for carotid stenosis.

OBJECTIVE: We aimed to identify factors associated with cost of carotid artery stenting (CAS). METHODS: Patient and hospital characteristics affecting cost of admission for CAS were identified using the Vizient national database of hospital-reported outcomes. Patients who underwent CAS for either asymptomatic or symptomatic carotid stenosis were identified using surgical Medicare Severity-Diagnosis Related Groups and appropriate International Classification of Diseases, Ninth Revision and Tenth Revision codes. RESULTS: There were 166 hospitals that reported outcomes from 7369 inpatient admissions for CAS. Each institution reported a mean value for cost related to patient care per admission for CAS; the average cost across all reporting institutions was $12,834.14 (standard error of the mean [SEM], 492.88). Institutions in the lowest 25th percentile with respect to frequency of intensive care unit admission after CAS had lower cost of admission than institutions above the 75th percentile ($10,971.30 [SEM, 460.67] vs $14,992.90 [964.29]; P = .002), without any differences in incidence of stroke during admission (2.2% [SEM, 0.3] vs 2.0% [0.4]; P = .877) or 30-day readmission (1.9% [SEM, 0.4] vs 2.5 [0.6]; P = .329). Admissions for patients with symptomatic stenosis were more expensive than those with asymptomatic stenosis ($20,462.10 [SEM, 819.93] vs $11,285.20 [347.11]; P < .001). Obesity was also associated with greater costs of admission ($14,176.20 [SEM, 597.13] vs $12,287.10 [395.73]; P < .001). CONCLUSIONS: Admission to an intensive care unit, symptomatic stenosis, and obesity were associated with increased costs in patients undergoing CAS. These data may aid in identifying opportunities to improve the cost-effectiveness of this procedure.

Editor's Choice - Carotid Stenosis Treatment: Variation in International Practice Patterns.

OBJECTIVES: The aim was to determine current practice for the treatment of carotid stenosis among 12 countries participating in the International Consortium of Vascular Registries (ICVR). METHODS: Data from the United States Vascular Quality Initiative (VQI) and the Vascunet registry collaboration (including 10 registries in Europe and Australasia) were used. Variation in treatment modality of asymptomatic versus symptomatic patients was analysed between countries and among centres within each country. RESULTS: Among 58,607 procedures, octogenarians represented 18% of all patients, ranging from 8% (Hungary) to 22% (New Zealand and Australia). Women represented 36%, ranging from 29% (Switzerland) to 40% (USA). The proportion of carotid artery stenting (CAS) among asymptomatic patients ranged from 0% (Finland) to 26% (Sweden) and among symptomatic patients from 0% (Denmark) to 19% (USA). Variation among centres within countries for CAS was highest in the United States and Australia (from 0% to 80%). The overall proportion of asymptomatic patients was 48%, but varied from 0% (Denmark) to 73% (Italy). There was also substantial centre level variation within each country in the proportion of asymptomatic patients, most pronounced in Australia (0-72%), Hungary (5-55%), and the United States (0-100%). Countries with fee for service reimbursement had higher rates of treatment in asymptomatic patients than countries with population based reimbursement (OR 5.8, 95% CI 4.4-7.7). CONCLUSIONS: Despite evidence about treatment options for carotid artery disease, the proportion of asymptomatic patients, treatment modality, and the proportion of women and octogenarians vary considerably among and within countries. There was a significant association of treating more asymptomatic patients in countries with fee for service reimbursement. The findings reflect the inconsistency of the existing guidelines and a need for cooperation among guideline committees all over the world.

Modifiable Factors Leading to Increased Length of Stay after Carotid Endarterectomy.

BACKGROUND: Carotid endarterectomy (CEA) is a commonly performed vascular operation. Yet, postoperative length of stay (LOS) varies greatly even within institutions. In this study, the morbidity and mortality, as well as financial impact of increased LOS were reviewed to establish modifiable factors associated with prolonged hospital stay. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was used to identify all patients undergoing primary CEA at a single institution between June 1, 2011 and November 28, 2014. Preoperative patient characteristics, intraoperative details, postoperative factors, long-term outcomes, and cost data were reviewed using an Institutional Review Board-approved prospectively collected database. Multivariate analysis was used to determine statistical difference between patients with LOS ≤1 day and >1 day. RESULTS: Complete 30-day variable and cost data were available for 219 patients with an average follow-up of 12 months. Seventy-nine (36%) patients had an LOS > 1 day. Variables determined to be statistically significant predictors of prolonged LOS included preoperative creatinine (P = 0.02) and severe congestive heart failure (P = 0.05) with self-pay status (P = 0.02) and preoperative beta-blocker therapy (P = 0.04) being protective. Shunt placement (P = 0.04), arterial re-exploration, and postoperative cardiac (P = 0.001) or neurological (P = 0.03) complications also resulted in prolonged hospitalization. Specific modifiable risk factors that contributed to increased LOS included operative start time after noon (P = 0.04), drain placement (P = 0.05), prolonged operative time (101 vs. 125 min, P = 0.01), return to the operating room (P = 0.01), and postoperative hypertension (P = 0.02) or hypotension (P = 0.04). Of note, there was no difference in LOS associated with technique (conventional versus eversion), patch use (P = 0.49), protamine administration (P = 0.60), electroencephalogram monitoring (P = 0.45), measurement of stump pressure (P = 0.63), Doppler (P = 0.36), or duplex (P = 0.92). Both hospital charges (P = 0.0001) and costs (P = 0.0001) were found to be significantly higher in patients with prolonged LOS, with no difference in physician charges (P = 0.10). Increased LOS after CEA was associated with an increase in 12-month mortality (P = 0.05). CONCLUSIONS: Increased LOS was associated with increased hospital charges, costs, as well as significant morbidity and midterm mortality following CEA. Furthermore, this study highlights several modifiable risk factors leading to increased LOS. Identified factors associated with increase LOS can serve as targets for improving care in vascular surgery.

A Cost Analysis of Regional Versus General Anesthesia for Carotid Endarterectomy.

BACKGROUND: Medical care in the United States has evolved into a more cost-conscious value-based health care system that necessitates a comparison of costs when there are alternative interventions considered to be acceptable in the treatment of a disease. This study compares the cost differences between regional anesthesia (RA) and general anesthesia (GA) for carotid endarterectomy (CEA). METHODS: Data from 346 consecutive patients who underwent CEA between January 2012 and September 2014 were retrospectively reviewed for the type of anesthesia used, outcomes data, and cost variables. Overall hospital day costs were compared between RA and GA. Medians and interquartile ranges were compared using Wilcoxon-Mann-Whitney test. A P < 0.05 was considered statistically significant using 2-sided tests. RESULTS: Median overall costs for GA were significantly higher than median costs for RA (medians [with interquartile ranges], $10,140 [$7,158-$12,658] versus $7,122 [$5,072-$8,511], P < 0.001). Median total operative time for GA was significantly longer than median time for RA (168 [144-188] versus 134 [115-147] min, P < 0.001). Median in-hospital length of stay (LOS) for GA was significantly longer compared with RA (2.0 vs 1.2 days, P < 0.001). Patients who received GA were also more likely to be admitted to the intensive care unit. CONCLUSIONS: Decreased cost, operating room expenses, postoperative resources, and overall LOS were observed for individuals who underwent RA for CEA as compared with GA. In summary, RA is more cost-effective and should be the optimal choice when clinically appropriate.

Modified Eversion Carotid Endarterectomy (mECEA): Analysis of Clinical and Financial Outcomes.

BACKGROUND: Several carotid endarterectomy techniques have been described, including conventional carotid endarterectomy (CCEA) performed with patch repair and eversion carotid endarterectomy (ECEA) performed with transection of the internal carotid artery. We describe our simplified technique of modified eversion carotid endarterectomy (mECEA) with longitudinal arteriotomy limited to the carotid bulb, without transection of the internal carotid artery and present our analysis of its safety, efficacy, and cost effectiveness. METHODS: A retrospective review of all carotid endarterectomies performed by 3 vascular surgeons over a 3-year period was completed. About 197 mECEA were performed during the study period. Follow-up data were obtained on 77.7% of patients. A comparison was made with the contemporary literature with respect to outcomes for both CCEA and ECEA. RESULTS: Between January 2012 and December 2014, a total of 197 mECEA were performed. The perioperative stroke and death rates for those undergoing mECEA was 0.5% and 0.5%, respectively. Late stroke and death rates were 3.0% and 5.1%, respectively. Perioperative rate of myocardial infarction was 1.0%. Early restenosis rates of >70% occurred in 1.4%, whereas late restenosis of >70% occurred in 2.7%. Mean operating time for those undergoing mECEA was 57.9 min. Average costs savings for mECEA compared to CCEA were $5,835. CONCLUSIONS: This simplified technique has comparable outcomes to those described in the contemporary literature for both CCEA and ECEA with respect to postoperative neurologic events as well as restenosis rates. In our institution, the short mean operative times with mECEA has led to reduced resource utilization.

Reimbursement Policies for Carotid Duplex Ultrasound that are Based on International Classification of Diseases Codes May Discourage Testing in High-Yield Groups.

BACKGROUND: To curb increasing volumes of diagnostic imaging and costs, reimbursement for carotid duplex ultrasound (CDU) is dependent on "appropriate" indications as documented by International Classification of Diseases (ICD) codes entered by ordering physicians. Historically, asymptomatic indications for CDU yield lower rates of abnormal results than symptomatic indications, and consensus documents agree that most asymptomatic indications for CDU are inappropriate. In our vascular laboratory, we perceived an increased rate of incorrect or inappropriate ICD codes. We therefore sought to determine if ICD codes were useful in predicting the frequency of abnormal CDU. We hypothesized that asymptomatic or nonspecific ICD codes would yield a lower rate of abnormal CDU than symptomatic codes, validating efforts to limit reimbursement in asymptomatic, low-yield groups. MATERIAL AND METHODS: We reviewed all outpatient CDU done in 2011 at our institution. ICD codes were recorded, and each medical record was then reviewed by a vascular surgeon to determine if the assigned ICD code appropriately reflected the clinical scenario. CDU findings categorized as abnormal (>50% stenosis) or normal (<50% stenosis) were recorded. Each individual ICD code and group 1 (asymptomatic), group 2 (nonhemispheric symptoms), group 3 (hemispheric symptoms), group 4 (preoperative cardiovascular examination), and group 5 (nonspecific) ICD codes were analyzed for correlation with CDU results. RESULTS: Nine hundred ninety-four patients had 74 primary ICD codes listed as indications for CDU. Of assigned ICD codes, 17.4% were deemed inaccurate. Overall, 14.8% of CDU were abnormal. Of the 13 highest frequency ICD codes, only 433.10, an asymptomatic code, was associated with abnormal CDU. Four symptomatic codes were associated with normal CDU; none of the other high frequency codes were associated with CDU result. Patients in group 1 (asymptomatic) were significantly more likely to have an abnormal CDU compared to each of the other groups (P < 0.001, P < 0.001, P = 0.020, P = 0.002) and to all other groups combined (P < 0.001). CONCLUSIONS: Asymptomatic indications by ICD codes yielded higher rates of abnormal CDU than symptomatic indications. This finding is inconsistent with clinical experience and historical data, and we suggest that inaccurate coding may play a role. Limiting reimbursement for CDU in low-yield groups is reasonable. However, reimbursement policies based on ICD coding, for example, limiting payment for asymptomatic ICD codes, may impede use of CDU in high-yield patient groups.

Relationships between 2-Year Survival, Costs, and Outcomes following Carotid Endarterectomy in Asymptomatic Patients in the Vascular Quality Initiative.

BACKGROUND: Carotid endarterectomy (CEA) for asymptomatic patients with limited life expectancy may not be beneficial or cost-effective. The purpose of this study was to examine relationships among survival, outcomes, and costs within 2 years following CEA among asymptomatic patients. METHODS: Prospectively collected data from 3097 patients undergoing CEA for asymptomatic disease from Vascular Quality Initiative VQI registry were linked to Medicare. Models were used to identify predictors of 2-year mortality following CEA. Patients were classified as low, medium, or high risk of death based on this model. Next, we examined costs related to cerebrovascular care, occurrence of stroke, rehospitalization, and reintervention within 2 years following CEA across risk strata. RESULTS: Overall, 2-year mortality was 6.7%. Age, diabetes, smoking, congestive heart failure (CHF), chronic obstructive pulmonary disease, renal insufficiency, absence of statin use, and contralateral internal carotid artery (ICA) stenosis were independently associated with a higher risk of death following CEA. In-hospital costs averaged $7500 among patients defined as low risk for death, and exceeded $10,800 among high risk patients. Although long-term costs related to cerebrovascular disease were 2 times higher in patients deemed high risk for death compared with low risk patents ($17,800 vs. $8800, P = 0.001), high risk of death was not independently associated with a high probability of high cost. Predictors of high cost at 2 years were severe contralateral ICA stenosis, dialysis dependence, and American Society for Anesthesia Class 4. Both statin use and CHF were protective of high cost. CONCLUSIONS: Greater than 90% of patients undergoing CEA live long enough to realize the benefits of their procedure. Moreover, the long-term costs are supported by the effectiveness of this procedure at all levels of patient risk.

Carotid artery stenosis: cost-effectiveness of assessment of cerebrovascular reserve to guide treatment of asymptomatic patients.

PURPOSE: To project and compare the lifetime health benefits, health care costs, and incremental cost-effectiveness of a decision rule based on assessment of cerebrovascular reserve (CVR) compared with medical therapy and immediate revascularization in asymptomatic patients with carotid artery stenosis for prevention of stroke. MATERIALS AND METHODS: The three strategies compared included immediate revascularization (carotid endarterectomy) and ongoing medical therapy (with antiplatelet, statin, and antihypertensive agents plus lifestyle modification), medical therapy-based treatment with revascularization only for patients who progressed, and use of a CVR-based decision rule for treatment in which patients with CVR impairment undergo immediate revascularization and all others receive medical therapy. A decision analytic model was developed to project lifetime quality-adjusted life years (QALYs) and costs for asymptomatic patients with carotid stenosis with 70%-89% carotid luminal narrowing at presentation. Risks of clinical events, costs, and quality-of-life values were estimated on the basis of those in published sources. The analysis was conducted from a health care system perspective, with health and cost outcomes discounted at 3%. Results Total costs per person and lifetime QALYs were lowest for the medical therapy-based strategy ($14 597, 9.848 QALYs), followed by CVR testing ($16 583, 9.934 QALYs) and immediate revascularization ($20 950, 9.940 QALYs). The incremental cost-effectiveness ratio for the CVR-based strategy compared with the medical therapy-based strategy was $23 000 per QALY and for the immediate revascularization versus the CVR-based strategy was $760 000 per QALY. RESULTS: were sensitive to variations in model inputs for revascularization costs and complication risks and baseline stroke risk. CONCLUSION: CVR testing can be a cost-effective tool to identify asymptomatic patients with carotid stenosis who are most likely to benefit from revascularization.

The value and economic analysis of routine postoperative carotid duplex ultrasound surveillance after carotid endarterectomy.

BACKGROUND: Several studies have reported on the role of postoperative duplex ultrasound surveillance after carotid endarterectomy (CEA) with varying results. Most of these studies had a small sample size or did not analyze cost-effectiveness. METHODS: We analyzed 489 of 501 CEA patients with patch closure. All patients had immediate postoperative duplex ultrasound examination and were routinely followed up both clinically and with duplex ultrasound at regular intervals of 1 month, 6 months, 12 months, and every 12 months thereafter. A Kaplan-Meier analysis was used to estimate the rate of ≥50% and ≥80% post-CEA restenosis over time and the time frame of progression from normal to ≥50% or ≥80% restenosis. The cost of post-CEA duplex surveillance was also estimated. RESULTS: Overall, 489 patients with a mean age of 68.5 years were analyzed. Ten of these had residual postoperative ≥50% stenosis, and 37 did not undergo a second duplex ultrasound examination and therefore were not included in the final analysis. The mean follow-up was 20.4 months (range, 1-63 months), with a mean number of duplex ultrasound examinations of 3.6 (range, 1-7). Eleven of 397 patients (2.8%) with a normal finding on immediate postoperative duplex ultrasound vs 4 of 45 (8.9%) with mild stenosis on immediate postoperative duplex ultrasound progressed to ≥50% restenosis (P = .055). Overall, 15 patients (3.1%) had ≥50% restenosis, 9 with 50% to <80% and 4 with 80% to 99% (2 of these had carotid artery stenting reintervention), and 2 had late carotid occlusion. All of these were asymptomatic, except for one who had a transient ischemic attack. The mean time to ≥50% to <80% restenosis was 14.7 months vs 19.8 months for ≥80% restenosis after the CEA. Freedom from restenosis rates were 98%, 96%, 94%, 94%, and 94% for ≥50% restenosis and 99%, 98%, 97%, 97%, and 97% for ≥80% restenosis at 1 year, 2 years, 3 years, 4 years, and 5 years, respectively. Freedom from myocardial infarction, stroke, and deaths was not significantly different between patients with and without restenosis (100%, 93%, 83%, and 83% vs 94%, 91%, 86%, and 79% at 1 year, 2 years, 3 years, and 4 years, respectively; P = .951). The estimated charge of this surveillance was 3.6 × 489 (number of CEAs) × $800 (charge for carotid duplex ultrasound), which equals $1,408,320, to detect only four patients with ≥80% to 99% restenosis who may have been potential candidates for reintervention. CONCLUSIONS: This study shows that the value of routine postoperative duplex ultrasound surveillance after CEA with patch closure may be limited, particularly if the finding on immediate postoperative duplex ultrasound is normal or shows minimal disease.

Experience matters more than specialty for carotid stenting outcomes.

OBJECTIVE: The introduction of carotid stenting has led to a rapid rise in the number of vascular specialists performing this procedure. The Carotid Revascularization Endarterectomy vs Stenting Trial (CREST) has shown that carotid stenting can be performed with an equivalent major event rate compared with carotid endarterectomy. However, there is still controversy about the appropriate training and experience required to safely perform this procedure. This observational study examined the performance of carotid stenting with regard to specialty and case volume. METHODS: From 2004 to 2011, inpatients diagnosed with carotid stenosis who had a carotid stenting procedure were extracted from the Nationwide Inpatient Sample database. The cohort was separated on the basis of the provider performing the procedure (surgeon vs interventionalist), hospital location, and volume. Surgeons were defined as providers who also performed either a carotid endarterectomy or femoral-popliteal bypass during the same time interval. Primary end points analyzed included stroke, myocardial infarction, and 30-day mortality. Length of stay and hospital costs were also analyzed as secondary outcomes. RESULTS: A total of 20,663 cases of carotid stenting were found; 15,305 (74%) cases were identified to be performed by a "surgeon," whereas 5358 (26%) were done by an "interventionalist." The majority of cases were done at hospitals in urban locations (96.51%) and designated teaching institutions (61.47%). Unadjusted outcomes were similar between surgeons and interventionalists in terms of stroke (4.33% and 4.41%), myocardial infarction (2.10% and 2.13%), and mortality (0.84% and 1.03%) respectively. Qualitatively, volume per 10 cases was shown to decrease the risk of stroke. Adjusted multivariate analysis demonstrated no statistical significance between primary end point outcomes. However, length of stay (2.81 vs 3.08 days) and total charges ($48,087.61 and $51,718.77) were lower for procedures performed by surgeons. CONCLUSIONS: Surgeons are performing the majority of carotid stent procedures in the United States. The volume of cases performed by a provider, rather than the provider's specialty, appears to be a stronger predictor of adverse outcomes for carotid stenting. There were, however, significant cost differences between surgeons and interventionalists, which needs to be further evaluated at an institutional level.

Care of patients undergoing vascular surgery at safety net public hospitals is associated with higher cost but similar mortality to nonsafety net hospitals.

OBJECTIVE: This study compared in-hospital mortality and resource utilization among vascular surgical patients at safety net public hospitals (SNPHs) with those at nonsafety net public hospitals (nSNPHs). METHODS: The National Inpatient Sample (2003-2011) was queried to identify surgical patients with peripheral arterial disease (PAD), carotid stenosis, or nonruptured abdominal aorta aneurysm based on International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic and procedure codes. The cohort was then divided into SNPH and nSNPH groups according to the definition of SNPH used by the National Association of Public Hospitals. Clinical characteristics, length of stay, in-hospital mortality, and hospital charges were compared between groups. Advanced PAD was defined as that associated with rest pain or tissue loss. Statistical methods included bivariate χ(2) tests for categoric variables, t-tests for continuous variables, and multivariable linear and logistic regression to adjust for confounding variables (in-hospital mortality). RESULTS: We identified 306,438 patients operated on for PAD, carotid stenosis, and abdominal aortic aneurysm. Patients at SNPHs were younger, the percentage of female and minority patients was higher, and patients had a higher Elixhauser comorbidity index (P < .001). Nonelective admissions were more common among SNPH patients who presented with more advanced PAD (P > .05) and symptomatic carotid stenosis (P < .05). Patients at SNPHs had a significantly longer length of stay, higher hospital charges, and higher in-hospital mortality (P < .05 for all variables). Crude odds of mortality at SNPHs were 1.28 higher than at nSNPHs (95% confidence interval, 1.13-1.46; P < .001), but adjusted analyses revealed no statistically significant difference between the odds of in-hospital mortality at both hospital groups. CONCLUSIONS: Patients undergoing vascular surgery at SNPHs, despite being younger, had higher comorbidities, presented more urgently with more advanced disease, and incurred higher costs than the SNPH cohort despite similar adjusted odds of in-hospital mortality. Delayed presentation and higher comorbidities are most likely related to poor access to routine and preventive health care for the SNPH patients.

The impact of regulatory approval and Medicare coverage on outcomes of carotid stenting.

BACKGROUND: Carotid artery stenting (CAS) was introduced in the United States nearly a decade ago as a novel treatment of severe carotid stenosis. Voluminous and high-quality prospective data permit analysis of longitudinal trends in CAS outcomes. METHODS: Outcomes from all prospective trials with the Food and Drug Administration (FDA) oversight from 2000-2011 were reviewed, as were the subset of studies using a single CAS system. All studies shared common inclusion/exclusion criteria, endpoints, independent assessment/adjudication of neurological events, and were conducted in accordance with FDA regulations. Death and stroke (DS) rates from FDA-approved studies in high-surgical-risk patients were assessed. RESULTS: Between 2000 and 2011, two distinct periods with clustered and differentiated outcomes in CAS IDE trials were observed, separated by FDA approval and Centers for Medicare and Medicaid Services (CMS) coverage in 2004-2005. The mean 30-day DS rate in the first wave (2000-2004) of CAS trials was 5.3% (95% CI: 4.6-6.2%), and fell significantly to 2.6% (95% CI: 1.9-3.7%; P = 0.0001) in the second wave (2006-2011). This decline occurred during a simultaneous, independent 24-fold increase in monitored CAS activity. This decline in DS rates was observed in symptomatic and asymptomatic patients, alike independent of device tested. CONCLUSIONS: Declines in periprocedural DS rates in CAS appear linked to regulatory and coverage approvals leading to increased operator experience along with continued regulatory oversight, and provide insight into the introduction of other novel therapies.