Abstract
Objective:
Current guidelines state that the acceptable 30-day post-operative stroke/death rate after carotid endarterectomy (CEA) is <3% for asymptomatic patients and <6% for symptomatic patients. The Centers for Medicare and Medicaid Services (CMS) has identified certain high-risk characteristics used to define patients at highest risk for CEA for whom carotid artery stenting would be reimbursed. We evaluated the impact of CMS physiologic and anatomic high-risk criteria on major adverse event rates following CEA in asymptomatic and symptomatic patients.
Methods:
We retrospectively reviewed all patients undergoing CEA from 2011–2017 in the ACS-NSQIP vascular targeted database. Patients with high-risk anatomic or physiologic characteristics were identified by a predefined variable and were compared to normal risk patients. The primary outcome was 30-day stroke/death, stratified by symptom status.
Results:
We identified 25,788 patients undergoing CEA, of which 60% were treated for asymptomatic carotid disease. Among all patients, high-risk physiology or anatomy was associated with higher rates of 30-day stroke/death compared to normal risk patients (physiology: 4.6 vs 2.3%, P < .001; anatomy: 3.6 vs 2.3%, P < .001). Patients who met criteria for high-risk physiology or anatomy also had higher rates of cardiac events (physiology: 3.1 vs 1.6%, P < .001; anatomy: 2.3 vs 1.6%, P < .01), but only patients with high risk anatomy had higher rates of cranial nerve injury (physiology: 2.4 vs 2.5%, P = .81; anatomy: 4.3 vs 2.5%, P < .001). Asymptomatic patients with high-risk physiology or anatomy had higher rates of 30-day stroke/death, especially in the physiologic high-risk group (physiology: 4.7 vs 1.5%, P <.001; anatomy: 2.6 vs 1.5%, P < .01), compared to normal risk patients. However, among symptomatic patients, differences in stroke/death were only seen with high-risk anatomic and not high risk-physiologic patients (physiology: 4.6 vs 3.4%, P = .12; anatomy: 4.8 vs 3.4%, P = .01).
Conclusions:
As currently selected, contemporary real-world outcomes following CEA in asymptomatic carotid disease patients meeting high-risk physiologic criteria show an unacceptably high 30-day stroke/death rate, well above the 3% threshold. These results suggest the need for better patient selection and preoperative optimization prior to elective CEA.
Table of Contents Summary
This ACS-NSQIP study of 25,788 patients validates the CMS high-risk criteria and reveals that the current perioperative 30-day stroke/death rate after carotid endarterectomy in high physiologic risk patients with asymptomatic carotid stenosis is 4.7%, well above the acceptable rate of less than 3%. Better patient selection for carotid revascularization may help reduce this high incidence of stroke/death in this population.
INTRODUTION
Carotid endarterectomy (CEA) is the gold standard revascularization option for carotid artery disease. Several factors have been used to help guide treatment of carotid stenosis, including symptom status, degree of stenosis, perioperative risk of stroke/death, life expectancy, physiologic risk factors including cardiovascular comorbidities, and anatomic risk factors such as contralateral carotid occlusion and prior neck irradiation. The most recent Society for Vascular Surgery (SVS) guideline for management of carotid disease recommends CEA as first-line intervention for asymptomatic patients with >60% stenosis when perioperative risk of stroke/death is ≤3% and the patient’s life expectancy is 3–5 years.1 For symptomatic patients with >50% stenosis, CEA is recommended over carotid artery stenting (CAS) specifically in patients who are over 70 years old and in patients without anatomic or physiologic risk factors. With lesser degree of evidence, the guideline recommends CAS over CEA in symptomatic patients with >50% stenosis who meet specific high-risk anatomic and physiologic characteristics.
The Centers for Medicaid and Medicare Services (CMS) has also provided a set of high-risk medical and anatomic criteria, used to identify patients at highest risk for CEA for whom carotid artery stenting would be reimbursed.2 Based on these CMS definitions, patients are classified as “high risk” for CEA if they have comorbidities such as CHF class III/IV, left ventricular ejection fraction <30%, unstable angina, a contralateral carotid occlusion, a recent MI, prior CEA with recurrent stenosis, or prior neck radiation.
However, several studies have questioned the role of transfemoral carotid stenting in high-risk patients given consistent findings of higher perioperative stroke/death rates in this high-risk population compared to CEA.3,4 If future evidence continues to show that transfemoral carotid stenting is not a viable option, it will be important to understand the current rate of major adverse events following CEA in these high-risk patients. In this retrospective study of prospectively collected data in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP), our objectives were to (1) validate the CMS physiologic and anatomic high-risk criteria against a large national cohort of patients undergoing CEA and (2) compare outcomes for high anatomic and high physiologic risk versus normal risk patients presenting with and without neurological symptoms. This study presents a unique opportunity to shed further light on the circumstances for which CEA will be more effective and associated with better outcomes.
METHODS
Dataset
We identified all patients undergoing CEA in the ACS-NSQIP Vascular Surgery targeted module from 2011–2017. The ACS-NSQIP is a multi-institutional collaboration that uses trained clinical reviewers to collect preoperative, intraoperative, and 30-day outcome data on a sample of eligible procedures at participating hospitals. To ensure comprehensive data collection, trained clinical reviewers utilize a combination of electronic chart review and rigorous 30-day follow-up with phone calls to patients if necessary. Additional information on the NSQIP is available at https://www.facs.org/quality-programs/acs-nsqip.
Patients and Cohorts
We identified 26,293 patients in the vascular surgery targeted NSQIP module undergoing CEA. Vascular surgeons performed 93.5% of all CEA procedures during the study period. Patients with no documentation of open carotid surgical procedure (n=31, 0.1%) were excluded from analysis. Because we analyzed patients undergoing carotid revascularization based on presenting symptom status, patients with no documentation of preoperative symptom status were also excluded from analysis (n=474, 1.8%). The CEA module provides a binary variable for patients meeting any high-risk physiologic or high-risk anatomic factor based on the CMS high-risk guidelines. However, there are no details available for which specific physiologic or anatomic risk factors each patient met. We compared normal risk patients (no high-risk anatomic or physiologic criteria) with high anatomic risk and high physiologic risk patients.
A list of all variable definitions captured by the NSQIP can be found at https://www.facs.org/quality-programs/acs-nsqip. Preoperative symptom status included prior ipsilateral stroke, amaurosis fugax, and hemispheric transient ischemic attack (TIA). Severe obesity was defined as body mass index > 40 kg/m2. Congestive heart failure (CHF) included a new diagnosis in the past 30 days or an exacerbation prior to carotid revascularization. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to calculate glomerular filtration rate and chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (GFR) of less than 60 mL/min/1.73m2.5 The NSQIP captures outcomes within 30 days of the index operation. The primary outcome measured was stroke/death. Other major individual adverse events assessed include stroke, death, cardiac events, and cranial nerve injuries. Cardiac events were defined as myocardial infarction or arrhythmias.
Statistical Analysis
Continuous variables were presented as mean ± standard deviation, or as median and interquartile range (IQR) based on the distribution normality. Categorial variables were presented as counts and percentages. Univariate differences between cohorts were assessed using χ2 and Fisher’s exact tests for categorical variables and Student’s t-tests or rank-sum tests for continuous variables where appropriate. NSQIP does not capture hospital or surgeon identifiers, so multi-level models are not possible. All tests were two-sided and P < .05 was considered statistically significant. Multivariable analysis was not performed given the study design comparing patients with baseline comorbid differences. Stata/SE 15.1 (StataCorp, College Station, TX) was used for all analyses. Permission to use NSQIP data, without the need for informed consent due to the retrospective, de-identified nature of data, was obtained from the Institutional Review Board at Beth Israel Deaconess Medical Center.
RESULTS
Patient Characteristics
A total of 25,788 patients underwent CEA between 2011 and 2017, of which 14,756 (60%) were treated for asymptomatic disease. Of patients with documented high-risk assessment, 1,278 (5.0%) met high physiologic risk criteria and 2,823 (11%) met high anatomic risk criteria. Over the study period, the proportion of high physiologic risk patients treated with endarterectomy in the NSQIP has remained relatively stable, whereas the proportion of high anatomic risk patients has decreased from 13% in 2011 to 9.7% in 2017 (Figure 1). Baseline demographics and characteristics are shown in Table I. Compared to normal risk patients, patients meeting high physiologic risk criteria were older (73 vs 71 years, p < .001) and were more likely to have hypertension (88 vs 83%, p<.001), chronic obstructive pulmonary disease (17 vs 9.4%, P < .001), CHF (17 vs 0.6%, P < .001), diabetes (38 vs 31%, p < .001), CKD (48 vs 34%, P < .001) and be dialysis dependent (3.6 vs 1.0%, p < .001). However, high physiologic risk patients were less likely to be female (36 vs 39%, P = .04) and white (89 vs 93%, P < .001).
Figure 1.
Proportion of High-risk Physiologic and Anatomic Patients in the ACS-NSQIP Treated with Carotid Endarterectomy
Table I.
Baseline Characteristics of Patients Undergoing Carotid Endarterectomy with High-risk Physiology and Anatomy
| Normal Risk | High Risk Physiology | High Risk Anatomy | ||||
|---|---|---|---|---|---|---|
| N = 21,615 (%) |
N = 1,278 (%) |
N = 2,823 (%) |
||||
| Age, years, mean±SD | 71±9.2 | Ref | 73±10 | <.001 | 71±9.2 | <.01 |
| Female | 39 | Ref | 36 | .04 | 35 | <.001 |
| White | 93 | Ref | 89 | <.001 | 91 | <.001 |
| Symptomatic | 42 | Ref | 51 | <.001 | 46 | <.001 |
| Stroke | 19 | Ref | 22 | <.01 | 23 | <.001 |
| TIA | 23 | Ref | 29 | <.001 | 23 | .62 |
| Hypertension | 83 | Ref | 88 | <.001 | 84 | .18 |
| COPD | 9.4 | Ref | 17 | <.001 | 12 | <.001 |
| CHF | 0.6 | Ref | 17 | <.001 | 2.4 | <.001 |
| Smoker | 26 | Ref | 25 | .30 | 32 | <.001 |
| Diabetes | 31 | Ref | 38 | <.001 | 29 | .16 |
| BMI, kg/m2, mean±SD | 29±5.7 | Ref | 29±6.0 | .51 | 29±5.6 | .17 |
| CKD, GFR<60 | 34 | Ref | 48 | <.001 | 35 | .26 |
| Dialysis dependence | 1.0 | Ref | 3.6 | <.001 | 1.4 | .03 |
| Aspirin | 89 | Ref | 90 | .54 | 91 | .01 |
| Statin | 81 | Ref | 84 | .03 | 85 | <.001 |
| Beta-blocker | 53 | Ref | 76 | <.001 | 59 | <.001 |
BMI, body mass index; CHF, congestive heart failure; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; SD, standard deviation; TIA, transient ischemic attack; value are % unless otherwise indicated.
Patients with high anatomic risk also had significantly more baseline co-morbidities compared to normal risk patients, including COPD (12 vs 9.4%, P < .001), CHF (2.4 vs 0.6%, P < .001), and dialysis dependence (1.4 vs 1.0, P = .03). High anatomic risk patients were more likely to be smokers (32 vs 26%, p < .001), but less likely to be female (35 vs 39%, P < .001) and white (91 vs 93%, P < .001). Compared to normal risk patients, both high physiologic risk and anatomic risk patients were more likely to be on statins (physiologic: 84 vs 81%, P = .03; anatomic 85 vs 81%, P < .001) and beta-blockers (physiologic: 76 vs 53%, P < .001; anatomic: 59 vs 53%, P < .001), but only high anatomic risk patients were more likely medically optimized with aspirin (91 vs 89%, p = .01).
High Risk Outcomes
Patients meeting high risk physiologic criteria had double the rate of stroke/death following CEA compared to normal risk patients (4.6 vs 2.3%, P < .001) (Table II). Both individual stroke (3.0 vs 1.9%, P < .01) and death rates (1.9 vs 0.6%, P < .001) were significantly higher. Additionally, perioperative cardiac events occurred nearly twice as often in high physiologic risk patients (3.1 vs 1.6%, P < .001). Patients with high risk anatomy also had significantly higher rates of major adverse events compared to normal risk patients, including perioperative stroke/death (3.6 vs 2.3%, P < .001), as well as for individual stroke (3.0 vs 1.9%, P < .001) and death (1.0 vs 0.6%, P < .01) (Table III). High anatomic risk patients had more cardiac events (2.3 vs 1.6%, P < .01) and higher rates of cranial nerve injury (4.3 vs 2.5%, P < .001) compared to normal risk patients.
Table II.
Major Adverse Events for Patients with and without High Risk Physiology
| Normal Risk n = 21,615 (%) |
High-Risk Physiology n = 1,278 (%) |
P-Value | |
|---|---|---|---|
| Stroke/Death | 2.3 | 4.6 | <.001 |
| Stroke | 1.9 | 3.0 | <.01 |
| Death | 0.6 | 1.9 | <.001 |
| Cardiac event | 1.6 | 3.1 | <.001 |
| Cranial nerve injury | 2.5 | 2.4 | .81 |
Table III.
Major Adverse Events for Patients with and without High Risk Anatomy
| Normal Risk n = 20,279 (%) |
High-Risk Anatomy n = 2,443 (%) |
P-Value | |
|---|---|---|---|
| Stroke/Death | 2.3 | 3.6 | <.001 |
| Stroke | 1.9 | 3.0 | <.001 |
| Death | 0.6 | 1.0 | <.01 |
| Cardiac event | 1.6 | 2.3 | <.01 |
| Cranial nerve injury | 2.5 | 4.3 | <.001 |
Asymptomatic Carotid Stenosis
Asymptomatic patients with high physiologic or anatomic risk had significantly higher rates of stroke/death compared to normal risk patients (physiologic: 4.7 vs 1.5%, P < .001; anatomic: 2.6 vs. 1.5%, P < .01) (Table IV). Patients in the asymptomatic group with either high physiologic or high anatomic risk also had higher individual stroke rates (physiologic: 2.6 vs 1.1%, P < .01; anatomic: 2.1 vs 1.1%, P < .01), while those with high physiologic risk had a nearly 6-fold increase in individual death rates (2.3 vs 0.4%, P < .001). Cardiac events occurred more often in high physiologic risk (3.7 vs 1.6%, P < .001) and high anatomic risk (2.3 vs 1.6%, P = .03) asymptomatic patients than in normal risk asymptomatic patients, and cranial nerve injuries were more frequent in high anatomic risk patients alone (4.4 vs 2.4%, P < .001).
Table IV.
Major Adverse Events for Asymptomatic Patients with and without High Risk Criteria
| Normal Risk n = 12,524 (%) |
P-Value | High-risk Physiology n = 621 (%) |
P-Value | High-risk Anatomy n = 1,524 (%) |
P-Value | |
|---|---|---|---|---|---|---|
| Stroke/Death | 1.5 | Ref | 4.7 | <.001 | 2.6 | <.01 |
| Stroke | 1.1 | Ref | 2.6 | <.01 | 2.1 | <.01 |
| Death | 0.4 | Ref | 2.3 | <.001 | 0.7 | .20 |
| Cardiac event | 1.6 | Ref | 3.7 | <.001 | 2.3 | .03 |
| Cranial nerve injury | 2.4 | Ref | 1.9 | .43 | 4.4 | <.001 |
Symptomatic Carotid Stenosis
Symptomatic patients with high anatomic risk had a higher rate of stroke/death compared to normal risk patients (4.8 vs 3.4%, P = .01) and a statistical trend towards higher rates of stroke alone (4.0 vs 3.0%, P = .06) (Table V). The individual death rate was higher in symptomatic patients with either high physiologic risk (1.5 vs 0.8%, P = .048) or high anatomic risk (1.5 vs 0.8%, P = .02). While cardiac events were more common among high physiologic and anatomic risk symptomatic patients (physiology: 2.6 vs 1.6%, P = .048; anatomic: 2.4 vs 1.6%, P = .03), cranial nerve injury was more common only among high anatomic risk symptomatic patients (4.2 vs 2.5%, P < .001). Compared to symptomatic patients, high physiologic risk patients undergoing CEA for asymptomatic disease had higher rates of death (2.3 vs 1.5%, P = .34) and cardiac events (3.7 vs 2.6%, P = .25), however these differences were not statistically significant.
Table V.
Major Adverse Events for Symptomatic Patients with and without High Risk Criteria
| Normal Risk n = 9,091 (%) |
P-Value | High-risk Physiology n = 657 (%) |
P-Value | High-risk Anatomy n = 1,299 (%) |
P-Value | |
|---|---|---|---|---|---|---|
| Stroke/Death | 3.4 | Ref | 4.6 | .12 | 4.8 | .01 |
| Stroke | 3.0 | Ref | 3.4 | .63 | 4.0 | .06 |
| Death | 0.8 | Ref | 1.5 | .048 | 1.5 | .02 |
| Cardiac event | 1.6 | Ref | 2.6 | .048 | 2.4 | .03 |
| Cranial nerve injury | 2.5 | Ref | 2.7 | .70 | 4.2 | <.001 |
DISCUSSION
Patients with high anatomic and physiologic risk have higher rates of major adverse events compared to patients with normal risk following CEA. As currently selected by NSQIP providers, asymptomatic patients with high physiologic risk have an unacceptably high incidence of perioperative stroke/death, well above the recommended guidelines of less than 3% for asymptomatic patients. Although limited by small sample sizes, we also found that asymptomatic high physiologic risk patients undergoing CEA have numerically higher rates of death and cardiac events compared their symptomatic counterparts, but these differences were not statistically different. These findings suggest that improvement is needed in the contemporary management of high-risk patients with carotid disease, including patient selection for CEA treatment.
A study using the SVS Vascular Registry raised similar concerns regarding treatment of carotid disease in this high-risk patient population. Patients undergoing CEA with either CMS high physiologic or anatomic risk were found to have a significantly higher incidence of 30-day major adverse events compared to normal risk patients for treatment of both asymptomatic and symptomatic disease, with stroke/death rates of 6.4% in symptomatic patients and 3.7% in asymptomatic patients.6 This study, instead of looking at an aggregate of high physiologic and anatomic risk patients, we evaluated the high-risk cohorts separately and found that CEA treatment in either cohort is individually associated with higher rates of stroke/death compared to normal risk patients. Therefore, with data from two separate national databases containing real-world outcomes following CEA, patients meeting CMS high risk criteria clearly have worse outcomes compared to normal risk patients. Furthermore, in this study, differences in stroke/death were primarily driven by outcome differences in asymptomatic patients rather than in symptomatic patients, and the outlier in stroke/death above the 3% threshold for treatment in asymptomatic patients exists only for high-risk physiologic patients and not in high-risk anatomic patients.
Other avenues of carotid management should likely be pursued in the asymptomatic high-risk physiologic patient population. Transfemoral CAS was initially introduced as a more minimally invasive option for carotid revascularization, in which some studies found decreased rates of perioperative myocardial infarction; however, multiple randomized trials have shown significantly increased risk of stroke/death following CAS compared to CEA.7,8 Furthermore, CMS high-risk patients undergoing CAS have also been found to have significantly higher risks of 30-day and 2-year stroke compared to patients undergoing CEA in the SVS Vascular Quality Initiative (VQI) carotid stenting database.4 Therefore, real word outcomes following CAS have all failed to give reasonable equipoise for transfemoral CAS to be a viable treatment alternative to CEA in both normal and high-risk patients.
Transcarotid artery revascularization (TCAR) has been recently introduced as a novel approach for carotid stenting and may prove to be an option for carotid stenting in high-risk patients. Initial data from the SVS VQI TCAR Surveillance Project, which is an ongoing collaborative effort between the SVS, Food and Drug Administration, and CMS to evaluate the outcomes after TCAR in centers participating in the VQI, found TCAR to be equivalent to CEA and safer than transfemoral CAS, with half the odds of in-hospital adverse neurological events.9,10 Although the majority of patients currently treated with TCAR have high medical and or anatomic risk, the specific outcomes following TCAR treatment in high-risk patient populations is currently unknown and warrants further study.
Medical management for asymptomatic carotid stenosis has also been the subject of ongoing interest. Several randomized control trials from the 1980s to the early 2000s suggested that for patients with greater than 50%−60% stenosis, CEA was associated with lower rates of ipsilateral neurologic events, stroke/death, and long-term stroke (5-year) compared to the best medical therapy available at the time.11,12 Together, these trials contributed evidence supporting the current SVS guidelines: optimal medical therapy for patients with <60% stenosis and CEA for patients with >60% stenosis, risk of perioperative stroke or death less than 3%, and at least 3 year life expectancy. However, with recent advances in medical therapy, including the emergence of statins and antiplatelet therapies, ongoing trials such as CREST-2 are currently reexamining outcomes for asymptomatic normal-risk patients with >70% stenosis receiving intensive medical therapy alone versus CEA or CAS with intensive medical therapy.13,14 Although results from CREST-2 will be important in determining the role of medical management in asymptomatic non-high-risk patients, these benefits may not be applicable to high-risk patients. Medical management may prove to be a better management option for asymptomatic high-risk patients, however the natural history of stroke or death in these patients is currently unknown.
The selection criteria used for patients undergoing elective asymptomatic carotid revascularization are also important. Using our own institutional data of 830 patients treated with CEA from 2005–2010, we found no significant differences in perioperative stroke/death for asymptomatic patients with high-physiologic risk compared to normal risk patients (1.9 vs 1.4%, P = .71).15 Our institutional perioperative stroke/death rate of 1.9% in high physiologic risk patients is significantly lower than the perioperative stroke/death rates found in the NSQIP of 4.8%, which we attribute to better patient selection and diligent preoperative clearance in these high physiologic risk patients. A clinical risk score, such as one developed specifically for asymptomatic CEA patients to predict risk of complications and stroke/death should be employed to identify high-risk patients who would most benefit from CEA and help inform patients about the risks from revascularization.16
In this study, we found that over 50% of all carotid revascularization procedures in the United States are performed for asymptomatic carotid disease. However, the treatment paradigm for carotid disease varies worldwide. For example, in the Netherlands, treatment of asymptomatic carotid disease only comprises 2.8% of all carotid interventions.17 This reflects differences in practice patterns and patient selection. Whereas octogenarians, a high risk patient cohort, constitute 16.8% of all asymptomatic patients undergoing CEA in the U.S., octogenarians constitute 0%, 2%, 6.4%, and 7.4% of all asymptomatic patients treated in Finland, Sweden, Hungary and Norway, respectively.18 This global variation in patient selection and the current high rate of stroke/death following CEA in asymptomatic high-risk patients in the United States underscores the need to improve our current patient selection criteria and emphasizes the importance of identifying asymptomatic patients with specific high-risk characteristics who would most benefit from CEA.19,20
Our results must be interpreted within the context of the study design. There was no randomization in patient selection or treatment option given the retrospective nature of this study. The NSQIP does not include anatomical details and certain co-morbid conditions such as prior coronary artery disease, which may account for the higher rates of cardiac events for treatment of high anatomic risk patients. Intraoperative technical details used for the treatment of high-risk anatomic lesions, such as the use of shunts in patients with contralateral carotid occlusion, are not available in the NSQIP and therefore cannot be incorporated into this analysis. Furthermore, NSQIP does not collect out of hospital post-operation data beyond 30 days, rendering it impossible to evaluate differences in longer-term outcomes in this study. Regardless, our work opens up a number of exciting areas for future study. Although not fully available in our dataset, we encourage further investigation into the specific factors comprising the high risk physiologic and anatomic criteria that contribute the most to the high risk of stroke/death in asymptomatic patients.
Conclusion
High physiologic risk patients undergoing CEA for asymptomatic carotid disease have an unacceptably high incidence of stroke/death. Post-operative adverse events must be considered in the decision-making for carotid revascularization in these high-risk asymptomatic patients. A more thorough cardiac evaluation should be performed in the pre-operative process to help reduce the high incidence of MI in asymptomatic patients and future studies evaluating individual risk factors and their impact on natural history, perioperative event rates, and life expectancy will help guide treatment recommendations for this high-risk population.
ARTICLE HIGHLIGHTS.
Type of research:
National multi-center retrospective cohort study.
Key Finding:
Using data from the ACS-NSQIP vascular-targeted database of 25,788 patients undergoing carotid endarterectomy, patients with high physiologic risk or high anatomic risk have higher rates of 30-day major adverse events compared to normal risk patients. Asymptomatic carotid stenosis patients with high physiologic risk undergoing carotid endarterectomy have an unacceptably high post-operative 30-day stroke/death rate of 4.7%.
Take Home Message:
Better selection of asymptomatic high-risk patients undergoing carotid endarterectomy may help reduce the high incidence of 30-day stroke/death in this patient population.
Acknowledgments
VR is supported by the Harvard-Longwood Short-Term Research Training in Vascular Surgery NIH T35 Grant 5T35HL110843 (Program Director: Frank W. LoGerfo)
PL is supported by the Harvard-Longwood Research Training in Vascular Surgery NIH T32 Grant 2T32HL007734 (Program Director: Frank W. LoGerfo)
Footnotes
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References
- 1.Ricotta JJ, Aburahma A, Ascher E, Eskandari M, Faries P, Lal BK, et al. Updated Society for Vascular Surgery guidelines for management of extracranial carotid disease: executive summary. J Vasc Surg 2011. September;54(3):832–6. [DOI] [PubMed] [Google Scholar]
- 2.Medicare National Coverage Determinations Manual Chapter 1, Part 1 (Sections 10–80.12) Coverage Determinations Transmittals for Chapter 1, Part 1 [Internet] [cited 2019 Feb 6]. Available from: https://www.cms.gov/Regulations-and-Guidance/Guidance/Manuals/Downloads/ncd103c1_Part1.pdf
- 3.Giles KA, Hamdan AD, Pomposelli FB, Wyers MC, Schermerhorn ML. Stroke and death after carotid endarterectomy and carotid artery stenting with and without high risk criteria. J Vasc Surg 2010. December;52(6):1497–504. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Hicks CW, Nejim B, Locham S, Aridi HD, Schermerhorn ML, Malas MB. Association between Medicare high-risk criteria and outcomes after carotid revascularization procedures. J Vasc Surg 2018. June;67(6):1752–1761.e2. [DOI] [PubMed] [Google Scholar]
- 5.Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF, Feldman HI, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med 2009. May 5;150(9):604–12. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Schermerhorn ML, Fokkema M, Goodney P, Dillavou ED, Jim J, Kenwood CT, et al. The impact of Centers for Medicare and Medicaid Services high-risk criteria on outcome after carotid endarterectomy and carotid artery stenting in the SVS Vascular Registry. J Vasc Surg 2013. May;57(5):1318–24. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Moresoli P, Habib B, Reynier P, Secrest MH, Eisenberg MJ, Filion KB. Carotid Stenting Versus Endarterectomy for Asymptomatic Carotid Artery Stenosis: A Systematic Review and Meta-Analysis. Stroke 2017. August;48(8):2150–7. [DOI] [PubMed] [Google Scholar]
- 8.Brott TG, Hobson RW, Howard G, Roubin GS, Clark WM, Brooks W, et al. Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis. N Engl J Med 2010. July 1;363(1):11–23. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Malas MB, Dakour-Aridi H, Wang GJ, Kashyap VS, Motaganahalli RL, Eldrup-Jorgensen J, et al. Transcarotid artery revascularization versus transfemoral carotid artery stenting in the Society for Vascular Surgery Vascular Quality Initiative. J Vasc Surg 2019. January;69(1):92–103.e2. [DOI] [PubMed] [Google Scholar]
- 10.Schermerhorn ML, Liang P, Dakour-Aridi H, Kashyap VS, Wang GJ, Nolan BW, et al. In-Hospital Outcomes of TransCarotid Artery Revascularization and Carotid Endarterectomy in the Society of Vascular Sugery Vascular Quality Initiative. J Vasc Surg (In Press). [DOI] [PMC free article] [PubMed]
- 11.Hobson RW, Weiss DG, Fields WS, Goldstone J, Moore WS, Towne JB, et al. Efficacy of carotid endarterectomy for asymptomatic carotid stenosis. The Veterans Affairs Cooperative Study Group. N Engl J Med 1993. January 28;328(4):221–7. [DOI] [PubMed] [Google Scholar]
- 12.Halliday A, Mansfield A, Marro J, Peto C, Peto R, Potter J, et al. Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial. Lancet 2004. May 8;363(9420):1491–502. [DOI] [PubMed] [Google Scholar]
- 13.Moore WS. Issues to Be Addressed and Hopefully Resolved in the Carotid Revascularization Endarterectomy Versus Stenting Trial 2. Paraskevas KI, Mikhailidis DP, Veith FJ, editors. Angiology 2016. May 11;67(5):408–10. [DOI] [PubMed] [Google Scholar]
- 14.Howard VJ, Meschia JF, Lal BK, Turan TN, Roubin GS, Brown RD, et al. Carotid revascularization and medical management for asymptomatic carotid stenosis: Protocol of the CREST-2 clinical trials. Int J Stroke 2017. October 2;12(7):770–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Yoshida S, Bensley RP, Glaser JD, Nabzdyk CS, Hamdan AD, Wyers MC, et al. The current national criteria for carotid artery stenting overestimate its efficacy in patients who are symptomatic and at high risk. J Vasc Surg 2013. July;58(1):120–7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Calvillo-King L, Xuan L, Zhang S, Tuhrim S, Halm EA. Predicting risk of perioperative death and stroke after carotid endarterectomy in asymptomatic patients: derivation and validation of a clinical risk score. Stroke 2010. December;41(12):2786–94. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Pothof AB, van Koeverden ID, Pasterkamp G, Schermerhorn ML, de Borst GJ. Overtreatment or Undertreatment of Carotid Disease: A Transatlantic Comparison of Carotid Endarterectomy Patient Cohorts. Circ Cardiovasc Qual Outcomes 2018. April;11(4):e004607. [DOI] [PubMed] [Google Scholar]
- 18.Venermo M, Wang G, Sedrakyan A, Mao J, Eldrup N, DeMartino R, et al. Carotid Stenosis Treatment: Variation in International Practice Patterns. Eur J Vasc Endovasc Surg 2017. April;53(4):511–9. [DOI] [PubMed] [Google Scholar]
- 19.Nejim B, Obeid T, Arhuidese I, Hicks C, Wang S, Canner J, et al. Predictors of perioperative outcomes after carotid revascularization. J Surg Res 2016. August;204(2):267–73. [DOI] [PubMed] [Google Scholar]
- 20.Wu TY, Akopian G, Katz SG. Patients at elevated risk of major adverse events following endarterectomy for asymptomatic carotid stenosis. Am J Surg 2015. June;209(6):1069–73. [DOI] [PubMed] [Google Scholar]