National trends in utilization and postprocedure outcomes for carotid artery revascularization 2005 to 2007

Editor's Choice - Stroke and Death Following Carotid Endarterectomy or Carotid Artery Stenting: A Ten Year Nationwide Study in France

OBJECTIVE

This retrospective, nationwide cohort study aimed to compare peri-procedural stroke or death within 30 days of the procedure (PPSD30) in patients who underwent carotid endarterectomy (CEA) or carotid stenting (CAS).

METHODS

This retrospective cohort study used data from the French hospital database PMSI. All patients who underwent CEA or CAS between 2010 and 2019 in France were included. Information on individual patients and hospital characteristics was retrieved. A random effects logistic regression model compared the occurrence of PPSD30 after CEA or CAS. High surgical risk was accounted for by using propensity score matching and adjusted for patient and hospital characteristics. Analyses were also stratified to consider symptomatic and asymptomatic patients separately.

RESULTS

Between 2010 and 2019, 164 248 patients underwent a carotid artery procedure in France: 156 561 CEA and 7 687 CAS (including about 25% asymptomatic women and 40% high risk patients). The PPSD30 rate was 1.5% overall (n = 2 514 patients) (1.5% after CEA vs. 2.4% after CAS), 1.3% in asymptomatic patients (1.2% after CEA vs. 1.8% after CAS), and 3.3% in symptomatic patients (3.1% after CEA vs. 6.5% after CAS). After matching and adjustment, the risk of PPSD30 was statistically significantly greater in patients who underwent CAS than in patients who underwent CEA (adjusted OR [aOR] 1.4, 95% confidence interval [CI] 1.1 - 1.8 overall; aOR 1.4, 95% CI 1.1 - 1.8 in asymptomatic patients; and aOR 2.7, 95% CI 1.8 - 4.0 in symptomatic patients).

CONCLUSION

This nationwide real life study showed that CEA performed better than CAS, more markedly in symptomatic patients, but also in asymptomatic patients. Moreover, many patients received procedures that were more likely to be harmful than beneficial according to conclusions from past randomised trials (i.e., all asymptomatic women, all high surgical risk patients, and all who had undergone CAS).

Outcomes of redo vs primary carotid endarterectomy in the transcarotid artery revascularization era

OBJECTIVE

Outcomes following redo carotid endarterectomy (rCEA) have been shown to be worse than those after primary CEA (pCEA). Additional research has shown that outcomes are better with transcarotid artery revascularization (TCAR) for restenosis after CEA compared with rCEA and transfemoral carotid artery stenting; however, not all patients are eligible for TCAR or transfemoral carotid artery stenting. Given the increasing utilization of endovascular techniques, this study aims to evaluate changes in outcomes of rCEA vs pCEA before and after the approval of TCAR by the United States Food and Drug Administration in 2015.

METHODS

All patients between 2003 and 2023 who underwent CEA in the Vascular Quality Initiative were included and categorized as pCEA or rCEA. Cochrane-Armitage trend testing was used to examine trends in proportion of rCEA compared with pCEA, and the Mann-Kendall trend test was used for perioperative outcomes following rCEA overtime. Multivariable logistic regression was used to compare in-hospital stroke/death, stroke, death, and stroke/death/myocardial infarction following rCEA vs pCEA after stratifying patients into two cohorts: 2003 to 2015 and 2016 to 2023 (before and after introduction of TCAR). Analysis was also performed based on preoperative symptoms.

RESULTS

Of 198,150 patients undergoing CEA, 98.4% were pCEA and 1.6% were rCEA. During the study period, the proportion of rCEA in the Vascular Quality Initiative decreased from 2.3% to 1.0% as endovascular methods became more available (P < .001). Trend testing of individual outcomes showed an increase in the stroke/death rate following rCEA over time (P = .019) despite an improvement in the death rate (P = .009). From 2003 to 2015, patients undergoing rCEA had higher odds of stroke/death compared with pCEA (2.4% vs 1.2%; adjusted odds ratio [aOR], 1.81; 95% confidence interval [CI], 1.14-2.73; P = .007). Higher stroke/death rates after rCEA persisted only in asymptomatic patients (2.3% vs 1.1%; aOR, 2.03; 95% CI, 1.19-3.25; P = .006); however, there was no difference in symptomatic patients (3.0% vs 2.0%; aOR, 1.37; 95% CI, 0.51;3.01; P = .50). In the late period, rCEA had higher odds of stroke/death compared with pCEA (3.1% vs 1.3%; aOR, 2.45; 95% CI, 1.85-3.18; P < .001), and the association was seen in asymptomatic patients (1.9% vs 1.0%; aOR, 1.95; 95% CI, 1.29-2.82; P < .001) and symptomatic patients (6.3% vs 2.0%; aOR, 3.23; 95% CI, 2.17-4.64; P < .001).

CONCLUSIONS

The proportion of rCEAs done yearly in the United States has been decreasing as endovascular options became available. As the rate of rCEA has decreased, outcomes have been worsening, with an increasing stroke/death rate seen over time, driven primarily by worse outcomes in symptomatic patients. Stroke/death rates for asymptomatic patients fall within Society for Vascular Surgery guidelines, and so the choice between rCEA, CAS, or medical management should be made after shared decision-making between a patient and their surgeon. However, with an in-hospital stroke death rate of over 6% symptomatic patients should be selected very carefully, as some are less likely to benefit from rCEA.

An analysis of the recommendations of the 2022 Society for Vascular Surgery clinical practice guidelines for patients with asymptomatic carotid stenosis

OBJECTIVE

Patients with asymptomatic carotid artery stenosis currently account for the majority of carotid interventions performed in the United States; therefore, the following article will review the 2022 Society for Vascular Surgery (SVS) clinical practice guidelines perspective in treating patient with asymptomatic carotid stenosis.

METHODS

A systemic review and meta-analysis were conducted by the evidence practice center of the Mayo Clinic using a specified population, intervention, comparison, outcome (PICO) framework.

RESULTS

Based on published randomized trials and related supporting evidence, the following were noted: the SVS recommends that patients with asymptomatic ≥70% stenosis can be considered for carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), or transfemoral carotid artery stenting (TFCAS) for the reduction of long-term risk of stroke, provided the patient has a life expectancy of 3 to 5 years with risk of perioperative stroke and death not exceeding 3%. The type of carotid intervention should be based on the presence or absence of high-risk criteria for each specified intervention. Data from CREST, ACT, and the Vascular Quality Initiative suggest that certain properly selected asymptomatic patients can be treated with carotid stenting with equivalent outcome to CEA in the hands of experienced interventionalists. The institutions and operator performing carotid stenting must exhibit expertise sufficient to meet the established American Heart Association guidelines for treatment of patient with asymptomatic carotid stenosis (ie, combined stroke/death rate of less than 3%).

CONCLUSIONS

SVS recommends that low surgical risk patients with asymptomatic carotid stenosis of ≥70% to be treated with CEA with best medical therapy over medical therapy alone for the long-term prevention of stroke/death (GRADE 1B). Carotid intervention should also be based on the presence or absence of high-risk criteria for each specified intervention (ie, CEA, TCAR, and TFCAS).

Qualitative Analysis of Length of Stay and Readmission after Carotid Endarterectomy

BACKGROUND

Length of stay (LOS) and readmissions are common measures to evaluate quality of health care. The objective of this study was to evaluate factors related to hospital LOS and readmission within 90 days following carotid endarterectomy (CEA) in patients who have not had a stroke.

METHODS

Using a single institution database, patients who underwent CEA for carotid stenosis between 2014 and 2019 were identified. Asymptomatic carotid stenosis (no history of any stroke or transient ischemic attack (TIA) within 6 months prior to CEA), and patients who had a TIA without stroke were included. Demographic and perioperative factors were collected. Primary outcomes analyzed were increased LOS (>1 day) and readmission within 90 days after surgery.

RESULTS

There were 125 patients identified who underwent CEA for 133 carotid stenosis, and 8 patients had bilateral CEA; of which 36.8% were asymptomatic carotid stenosis with the remaining being operated on for TIA without any stroke. The mean age was 68 years old and 36.1% of cases were female. The median postoperative LOS was 2 days. Increased LOS occurred in 81 cases (60.9%). Increased LOS, compared to no increased LOS, occurred more often in patients with diabetes (48.1% vs. 30.8%, P = 0.047), in those with operations starting after 12:00 pm (45.7% vs. 21.2%, P = 0.004) and those with any minor complications such as neck swelling, neck pain, and urinary retention (30.9% vs. 15.4%, P = 0.044). Readmission within 90 days after CEA occurred in 24 (18%) of cases. Readmission within 90 days, compared to no readmission within 90 days, occurred more often in patients with a history of coronary artery disease (58.3% vs. 27.5%, P = 0.004), congestive heart failure (37.5% vs. 11%, P = 0.001), and atrial fibrillation (29.2% vs. 8.3%, P = 0.004).

CONCLUSIONS

More than half of patients undergoing CEA for carotid stenosis were discharged after postoperative day 1. Interventions on modifiable clinical risk factors, such as morning CEA scheduling and management of comorbidities, may decrease LOS and 90-day readmission rates.

Extra-Cranial Carotid Artery Stenosis: An Objective Analysis of the Available Evidence

Background and Purpose

Carotid stenosis is arterial disease narrowing of the origin of the internal carotid artery (main brain artery). Knowing how to best manage this is imperative because it is common in older people and an important cause of stroke. Inappropriately high expectations have grown regarding the value of carotid artery procedures, such as surgery (endarterectomy) and stenting, for lowering the stroke risk associated with carotid stenosis. Meanwhile, the improving and predominant value of medical intervention (lifestyle coaching and medication) continues to be underappreciated.

Methods and Results

This article aims to be an objective presentation and discussion of the scientific literature critical for decision making when the primary goal is to optimize patient outcome. This compilation follows from many years of author scrutiny to separate fact from fiction. Common sense conclusions are drawn from factual statements backed by original citations. Detailed research methodology is given in cited papers. This article has been written in plain language given the importance of the general public understanding this topic. Issues covered include key terminology and the economic impact of carotid stenosis. There is a summary of the evidence-base regarding the efficacy and safety of procedural and medical (non-invasive) interventions for both asymptomatic and symptomatic patients. Conclusions are drawn with respect to current best management and research priorities. Several "furphies" (misconceptions) are exposed that are commonly used to make carotid stenting and endarterectomy outcomes appear similar. Ongoing randomized trials are mentioned and why they are unlikely to identify a routine practice indication for carotid artery procedures. There is a discussion of relevant worldwide guidelines regarding carotid artery procedures, including how they should be improved. There is an outline of systematic changes that are resulting in better application of the evidence-base.

Conclusion

The cornerstone of stroke prevention is medical intervention given it is non-invasive and protects against all arterial disease complications in all at risk. The "big" question is, does a carotid artery procedure add patient benefit in the modern era and, if so, for whom?

Accurate classification of carotid endarterectomy indication using physician claims and hospital discharge data

BACKGROUND AND PURPOSE

Studies of carotid endarterectomy (CEA) require stratification by symptomatic vs asymptomatic status because of marked differences in benefits and harms. In administrative datasets, this classification has been done using hospital discharge diagnosis codes of uncertain accuracy. This study aims to develop and evaluate algorithms for classifying symptomatic status using hospital discharge and physician claims data.

METHODS

A single center's administrative database was used to assemble a retrospective cohort of participants with CEA. Symptomatic status was ascertained by chart review prior to linkage with physician claims and hospital discharge data. Accuracy of rule-based classification by discharge diagnosis codes was measured by sensitivity and specificity. Elastic net logistic regression and random forest models combining physician claims and discharge data were generated from the training set and assessed in a test set of final year participants. Models were compared to rule-based classification using sensitivity at fixed specificity.

RESULTS

We identified 971 participants undergoing CEA at the Vancouver General Hospital (Vancouver, Canada) between January 1, 2008 and December 31, 2016. Of these, 729 met inclusion/exclusion criteria (n = 615 training, n = 114 test). Classification of symptomatic status using hospital discharge diagnosis codes was 32.8% (95% CI 29-37%) sensitive and 98.6% specific (96-100%). At matched 98.6% specificity, models that incorporated physician claims data were significantly more sensitive: elastic net 69.4% (59-82%) and random forest 78.8% (69-88%).

CONCLUSION

Discharge diagnoses were specific but insensitive for the classification of CEA symptomatic status. Elastic net and random forest machine learning algorithms that included physician claims data were sensitive and specific, and are likely an improvement over current state of classification by discharge diagnosis alone.

Differentiation of symptomatic and asymptomatic carotid intraplaque hemorrhage using 3D high-resolution diffusion-weighted stack of stars imaging

Ischemic events related to carotid disease are far more strongly associated with plaque instability than stenosis. 3D high-resolution diffusion-weighted (DW) imaging can provide quantitative diffusion measurements on carotid atherosclerosis and may improve detection of vulnerable intraplaque hemorrhage (IPH). The 3D DW-stack of stars (SOS) sequence was implemented with 3D SOS acquisition combined with DW preparation. After simulation of signals created from 3D DW-SOS, phantom studies were performed. Three healthy subjects and 20 patients with carotid disease were recruited. Apparent diffusion coefficient (ADC) values were statistically analyzed on three subgroups by using a two-group comparison Wilcoxon-Mann-Whitney U test with p values less than 0.05: symptomatic versus asymptomatic; IPH-positive versus IPH-negative; and IPH-positive symptomatic versus asymptomatic plaques to determine the relationship with plaque vulnerability. ADC values calculated by 3D DW-SOS provided values similar to those calculated from other techniques. Mean ADC of symptomatic plaque was significantly lower than asymptomatic plaque (0.68 ± 0.18 vs. 0.98 ± 0.16 x 10-3  mm2 /s, p < 0.001). ADC was also significantly lower in IPH-positive versus IPH-negative plaque (0.68 ± 0.13 vs. 1.04 ± 0.11 x 10-3  mm2 /s, p < 0.001). Additionally, ADC was significantly lower in symptomatic versus asymptomatic IPH-positive plaque (0.57 ± 0.09 vs. 0.75 ± 0.11 x 10-3  mm2 /s, p < 0.001). Our results provide strong evidence that ADC measurements from 3D DW-SOS correlate with the symptomatic status of extracranial internal carotid artery plaque. Further, ADC improved discrimination of symptomatic plaque in IPH. These data suggest that diffusion characteristics may improve detection of destabilized plaque leading to elevated stroke risk.

SOCIETY FOR VASCULAR SURGERY CLINICAL PRACTICE GUIDELINES FOR MANAGEMENT OF EXTRACRANIAL CEREBROVASCULAR DISEASE

Management of carotid bifurcation stenosis in stroke prevention has been the subject of extensive investigations, including multiple randomized controlled trials. The proper treatment of patients with carotid bifurcation disease is of major interest to vascular surgeons and other vascular specialists. In 2011, the Society for Vascular Surgery published guidelines for treatment of carotid artery disease. At the time, several randomized trials, comparing carotid endarterectomy (CEA) and carotid artery stenting (CAS), were published. Since that publication, several studies and a few systematic reviews comparing CEA and CAS have been published, and the role of medical management has been re-emphasized. The current publication updates and expands the 2011 guidelines with specific emphasis on five areas: is carotid endarterectomy recommended over maximal medical therapy in low risk patients; is carotid endarterectomy recommended over trans-femoral carotid artery stenting in low surgical risk patients with symptomatic carotid artery stenosis of >50%; timing of carotid Intervention in patients presenting with acute stroke; screening for carotid artery stenosis in asymptomatic patients; and optimal sequence for intervention in patients with combined carotid and coronary artery disease. A separate implementation document will address other important clinical issues in extracranial cerebrovascular disease. Recommendations are made using the GRADE (Grades of Recommendation Assessment, Development and Evaluation) approach, as has been done with other Society for Vascular Surgery guidelines. The committee recommends CEA as the first-line treatment for symptomatic low risk surgical patients with stenosis of 50% to 99% and asymptomatic patients with stenosis of 70% to 99%. The perioperative risk of stroke and death in asymptomatic patients must be <3% to ensure benefit for the patient. In patients with recent stable stroke (modified Rankin 0-2), carotid revascularization is considered appropriate in symptomatic patients with greater than 50% stenosis and is recommended and performed as soon as the patient is neurologically stable after 48 hours but definitely before 14 days of onset of symptoms. In the general population, screening for clinically asymptomatic carotid artery stenosis in patients without cerebrovascular symptoms or significant risk factors for carotid artery disease is not recommended. In selected asymptomatic patients who are at increased risk for carotid stenosis, we suggest screening for clinically asymptomatic carotid artery stenosis as long as the patients would potentially be fit for and willing to consider carotid intervention if significant stenosis is discovered. In patients with symptomatic carotid stenosis 50-99%, who require both CEA and CABG, we suggest CEA before or concomitant with CABG to potentially reduce the risk of stroke and stroke/death. The sequencing of the intervention depends on clinical presentation and institutional experience.

Trends and outcomes in Australian carotid artery revascularization surgery: 2010-2017

BACKGROUND

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) reduce the risk of stroke in patients with severe carotid stenosis. The aim was to compare contemporary treatment trends and outcomes after CEA and CAS between states of Australia.

METHODS

A retrospective analysis was conducted on data from the Australasian Vascular Audit between 2010 and 2017. The primary endpoint was perioperative stroke or death (S/D). We also analysed stroke and death independently and revascularization rates per 100 000 population.

RESULTS

A total of 15 413 patients underwent carotid revascularization (CEA 14 070; CAS 1343). S/D rates were similar for CEA and CAS (1.9% versus 1.8%; P = 0.37; symptomatic 2.1% versus 2.3%; P = 0.12; asymptomatic 1.5% versus 1.1%; P = 0.67). Patients ≥80 years (2.7% versus 1.7%; P = 0.01), those who had shunts (2.2% versus 1.7%; P = 0.03) or surgery in teaching hospitals (2.6% versus 1.4%; P = 0.02) had higher rates of S/D after CEA. Patients whose proceduralist used a cerebral protection device had lower S/D rates after CAS for symptomatic disease (4.8% versus 2.2%; P = 0.03). There was a wide variation in practice between states, where CAS as a proportion of total carotid procedures ranged from 0% to 17%, and a wide variation in outcomes, with rates of S/D varying between 1.4-6.6% for CEA and 0-6.7% after CAS.

CONCLUSION

Outcomes after CAS are equivalent to CEA when performed by vascular surgeons, however significant variation exists for both choice of revascularization procedure and perioperative outcomes between states. Further investigation is needed to determine whether clinical care pathways should be revised to achieve consistency and quality of outcomes.

Risk factors associated with 30-day hospital readmission after carotid endarterectomy

OBJECTIVE

The current study evaluated all-cause 30-day readmissions after carotid endarterectomy.

METHODS

Patients undergoing carotid endarterectomy were selected from the Cerner Health Facts® database using ICD-9-CM procedure codes from their index admission. Readmission within 30 days of discharge was determined. Chi-square analysis determined characteristics of the index admission (demographics, diagnoses, postoperative medications, and laboratory results) associated with readmission. Multivariate logistic regression models were used to identify characteristics independently associated with readmission.

RESULTS

In total, 5257 patients undergoing elective carotid endarterectomy were identified. Readmission within 30 days was 3.1%. After multivariable adjustment, readmission was associated with end-stage renal disease (OR: 3.21, 95% CI: 1.01-10.2), hemorrhage or hematoma (OR: 2.34, 95% CI: 1.15-4.77), procedural complications (OR: 3.07, 95% CI: 1.24-7.57), use of bronchodilators (OR: 1.48, 95% CI: 1.03-2.11), increased Charlson index scores (OR: 1.22, 95% CI: 1.08-1.38), and electrolyte abnormalities (hyponatremia < 135 mEq/L (OR: 1.69, 95% CI: 1.07-2.67) and hypokalemia less than 3.7 mEq/L (OR: 2.26, 95% CI: 1.03-4.98)).

CONCLUSIONS

Factors associated with readmission following carotid endarterectomy included younger age, increased comorbidity burden, end-stage renal disease, electrolyte disorders, the use of bronchodilators, and complications including bleeding (hemorrhage or hematoma). Of note, in this real-world study, only 40% of the patients received protamine, despite evidence-based literature demonstrating the reduced risk of bleeding complications. As healthcare moves towards quality of care-driven reimbursement, physician modifiable targets such as protamine utilization to reduce bleeding are greatly needed to reduce readmission, and failure to reduce preventable physician-driven complications after carotid interventions may be associated with decreased reimbursement.

In-hospital outcomes alone underestimate rates of 30-day major adverse events after carotid artery stenting

OBJECTIVE

Outcome studies using databases collecting only hospital discharge data underestimate morbidity and mortality because of failure to capture postdischarge events. The proportion of postdischarge major adverse events is well characterized in patients undergoing carotid endarterectomy (CEA) but has yet to be characterized after carotid artery stenting (CAS).

METHODS

We retrospectively reviewed all patients undergoing CAS from 2011 to 2017 using the American College of Surgeons National Surgical Quality Improvement Program procedure targeted database to evaluate rates of 30-day major adverse events, stratified by in-hospital and postdischarge occurrences. The primary outcome was 30-day stroke/death. Multivariable analysis using purposeful selection was used to identify independent factors associated with in-hospital, postdischarge, and 30-day stroke/death events.

RESULTS

Of the 899 patients undergoing CAS, reporting of in-hospital outcomes alone would yield a stroke/death rate of 2.7%, substantially underestimating the 30-day stroke/death rate of 4.0%. In fact, 35% of stroke/deaths, 27% of strokes, 73% of deaths, 35% of cardiac events, and 35% of stroke/death/cardiac events occurred after discharge. More postdischarge stroke/death events occurred after treatment of symptomatic compared with asymptomatic patients (47% vs 27%; P < .001). During this same study period, the 30-day stroke/death rate after CEA was 2.6%, with similar proportions of postdischarge strokes (28% vs 27%; P = .51) compared with CAS but lower proportions of postdischarge deaths (55% vs 73%; P < .001). After CAS, patients experiencing postdischarge stroke/death events had a shorter postoperative length of stay compared with patients with in-hospital stroke/death (1 [1-2] vs 5 [3-10] days; P < .001). Chronic obstructive pulmonary disease was independently associated with postdischarge stroke/death (odds ratio [OR], 4.4; 95% confidence interval [CI], 1.2-16; P = .02) after CAS. Nonwhite ethnicity was independently associated with overall 30-day stroke/death (OR, 3.4; 95% CI, 1.4-7.9; P < .01), whereas statin use was associated with not having stroke/death within 30 days (OR, 0.5; 95% CI, 0.2-1.0; P = .049).

CONCLUSIONS

More than one-quarter of perioperative strokes occur following discharge after both CAS and CEA. A higher proportion of postdischarge deaths occur after CAS in symptomatic patients, which may reflect treatment of a population of higher risk patients. Further investigation is needed to elucidate the cause of postdischarge stroke to develop methods to reduce these complications.

Misconceptions regarding the adequacy of best medical intervention alone for asymptomatic carotid stenosis

BACKGROUND

Medical intervention (risk factor identification, lifestyle coaching, and medication) for stroke prevention has improved significantly. It is likely that no more than 5.5% of persons with advanced asymptomatic carotid stenosis (ACS) will now benefit from a carotid procedure during their lifetime. However, some question the adequacy of medical intervention alone for such persons and propose using markers of high stroke risk to intervene with carotid endarterectomy (CEA) and/or carotid angioplasty/stenting (CAS). Our aim was to examine the scientific validity and implications of this proposal.

METHODS

We reviewed the evidence for using medical intervention alone or with additional CEA or CAS in persons with ACS. We also reviewed the evidence regarding the validity of using commonly cited makers of high stroke risk to select such persons for CEA or CAS, including markers proposed by the European Society for Vascular Surgery in 2017.

RESULTS

Randomized trials of medical intervention alone versus additional CEA showed a definite statistically significant CEA stroke prevention benefit for ACS only for selected average surgical risk men aged less than 75 to 80 years with 60% or greater stenosis using the North American Symptomatic Carotid Endarterectomy Trial criteria. However, the most recent measurements of stroke rate with ACS using medical intervention alone are overall lower than for those who had CEA or CAS in randomized trials. Randomized trials of CEA versus CAS in persons with ACS were underpowered. However, the trend was for higher stroke and death rates with CAS. There are no randomized trial results related to comparing current optimal medical intervention with CEA or CAS. Commonly cited markers of high stroke risk in relation to ACS lack specificity, have not been assessed in conjunction with current optimal medical intervention, and have not been shown in randomized trials to identify those who benefit from a carotid procedure in addition to current optimal medical intervention.

CONCLUSIONS

Medical intervention has an established role in the current routine management of persons with ACS. Stroke risk stratification studies using current optimal medical intervention alone are the highest research priority for identifying persons likely to benefit from adding a carotid procedure.

External validation of the Vascular Study Group of New England carotid endarterectomy risk predictive model using an independent U.S. national surgical database

OBJECTIVE

Previously, we described a Vascular Study Group of New England (VSGNE) risk predictive model to predict composite adverse outcomes (postoperative death, stroke, myocardial infarction, or discharge to extended care facilities) after carotid endarterectomy (CEA). The goal of this study was to externally validate this model using an independent database.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) CEA-targeted database (2010-2014) was used to externally validate the risk predictor model of adverse outcomes after CEA previously created using the VSGNE carotid database. Emergent cases and those in which CEA was combined with another operation were excluded. Cases in which a discharge destination cannot be determined were also excluded. To assess the predictive power of our VSGNE prediction score within this sample, a receiver operating characteristic curve was constructed. Risk scores for each NSQIP patient were also computed using beta weights from the VSGNE CEA model. To further assess the construct validity of our VSGNE prediction score, the observed proportion of adverse outcomes was examined at each level of our prediction scale and within five roughly equally sized risk groups formed on the basis of our VSGNE prediction scores.

RESULTS

In this database, 10,889 cases met our inclusion criteria and were used in this analysis. The overall rate of adverse outcomes in this cohort was 8.5%. External validation of the VSGNE model on this sample showed moderately good predictive ability (area under the curve = 0.745). Patients in progressively higher risk groups, based on their VSGNE model scores, exhibited progressively higher rates of observed adverse outcomes, as predicted.

CONCLUSIONS

The VSGNE CEA risk predictive model was externally validated on an NSQIP CEA-targeted sample and showed a fairly accurate global predictive ability for adverse outcomes after CEA. Although this model has a good population concordance, the lack of cut point indicates that individual risk prediction requires more evaluation. Further studies should be geared toward identification of variables that make this risk predictive model more robust.

Sensitivity of Administrative Coding in Identifying Inpatient Acute Strokes Complicating Procedures or Other Diseases in UK Hospitals

Background

Administrative hospital diagnostic coding data are increasingly used in “big data” research and to assess complication rates after surgery or acute medical conditions. Acute stroke is a common complication of several procedures/conditions, such as carotid interventions, but data are lacking on the sensitivity of administrative coding in identifying acute stroke during inpatient stay.

Methods and Results

Using all acute strokes ascertained in a population‐based cohort (2002–2017) as the reference, we determined the sensitivity of hospital administrative diagnostic codes (International Classification of Diseases, Tenth Revision; ICD‐10) for identifying acute strokes that occurred during hospital admission for other reasons, stratified by coding strategies, study periods, and stroke severity (National Institutes of Health Stroke Score</≥5). Of 3011 acute strokes, 198 (6.6%) occurred during hospital admissions for procedures/other diseases, including 122 (61.6%) major strokes. Using stroke‐specific codes (ICD‐10=I60–I61 and I63–I64) in the primary diagnostic position, 66 of the 198 cases were correctly identified (sensitivity for any stroke, 33.3%; 95% CI, 27.1–40.2; minor stroke, 30.3%; 95% CI, 21.0–41.5; major stroke, 35.2%; 95% CI, 27.2–44.2), with no improvement of sensitivity over time (P_trend=0.54). Sensitivity was lower during admissions for surgery/procedures than for other acute medical admissions (n/% 17/23.3% versus 49/39.2%; P=0.02). Sensitivity improved to 60.6% (53.6–67.2) for all and 61.6% (50.0–72.1) for surgery/procedures if other diagnostic positions were used, and to 65.2% (58.2–71.5) and 68.5% (56.9–78.1) respectively if combined with use of all possible nonspecific stroke‐related codes (ie, adding ICD‐10=I62 and I65–I68).

Conclusions

Low sensitivity of administrative coding in identifying acute strokes that occurred during admission does not support its use alone for audit of complication rates of procedures or hospitalization for other reasons.

Anesthesia type determines risk of cerebral infarction after carotid endarterectomy

OBJECTIVE

Silent and symptomatic cerebral infarctions occur in up to 34% of patients after carotid endarterectomy (CEA). This prospective study compared the risk of new brain infarctions detected by magnetic resonance imaging (MRI) in patients with internal carotid artery stenosis undergoing CEA with local anesthesia (LA) vs general anesthesia (GA).

METHODS

Consecutive patients with internal carotid artery stenosis indicated for CEA were screened at two centers. Patients without contraindication to LA or GA were randomly allocated to the LA or GA group by ZIP code randomization. Brain MRI was performed before and 24 hours after CEA. Neurologic examination was performed before and 24 hours and 30 days after surgery. The occurrence of new infarctions on the control magnetic resonance images, stroke, transient ischemic attack, and other complications was statistically evaluated.

RESULTS

Of 210 randomized patients, 105 underwent CEA with LA (67 men; mean age, 68.3 ± 8.1 years) and 105 with GA (70 men; mean age, 63.4 ± 7.5 years). New infarctions were more frequently detected on control magnetic resonance images in patients after CEA under GA compared with LA (17.1% vs 6.7%; P = .031). Stroke or transient ischemic attack occurred within 30 days of CEA in three patients under GA and in two under LA (P = 1.000). There were no significant differences between the two types of anesthesia in terms of the occurrence of other complications (14.3% for GA and 21.0% for LA; P = .277).

CONCLUSIONS

The risk of silent brain infarction after CEA as detected by MRI is higher under GA than under LA.

Surgical and Endovascular Treatment of Extracranial Carotid Stenosis

BACKGROUND

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) can be used to prevent stroke due to arteriosclerotic lesions of the carotid artery. In Germany, legally mandated quality assurance (QA) enables the evaluation of outcome quality after CEA and CAS performed under routine conditions.

METHODS

We analyzed data on all elective CEA and CAS procedures performed over the periods 2009-2014 and 2012-2014, respectively. The endpoints of the study were the combined in-hospital stroke and death rate, stroke rate and mortality separately, local complications, and other complications. We analyzed the raw data with descriptive statistics and carried out a risk-adjusted analysis of the association of clinically unalterable variables with the risk of stroke and death. All analyses were performed separately for CEA and CAS.

RESULTS

Data were analyzed from 142 074 CEA procedures (67.8% of them in men) and 13 086 CAS procedures (69.7% in men). The median age was 72 years (CEA) and 71 years (CAS). The periprocedural rate of stroke and death after CEA was 1.4% for asymptomatic and 2.5% for symptomatic stenoses; the corresponding rates for CAS were 1.7% and 3.7%. Variables associated with increased risk included older age, higher ASA class (ASA = American Society of Anesthesiologists), symptomatic vs. asymptomatic stenosis, 50-69% stenosis, and contralateral carotid occlusion (for CEA only).

CONCLUSION

These data reveal a low periprocedural rate of stroke or death for both CEA and CAS. This study does however not permit any conclusions as to the superiority or inferiority of CEA and CAS.

De-adoption and exnovation in the use of carotid revascularization: retrospective cohort study

Objective To determine physician characteristics associated with exnovation (scaling back on use) and de-adoption (abandoning use) of carotid revascularization.Design Retrospective longitudinal cohort study.Setting Medicare claims linked to the Doximity database provider registry, 2006-13.Participants 9158 physicians who performed carotid revascularization on Medicare patients between 2006 and 2013.Main outcome measures The primary outcomes were the number of carotid revascularization procedures for each physician per year at the end of the sample period, and the percentage change in the volume of carotid revascularization procedures.Results At baseline (2006-07), 9158 physicians performed carotid revascularization. By 2012-13 the use of revascularization in this cohort had declined by 37.7%, with two thirds attributable to scaling back (exnovation) rather than dropping the procedure entirely (de-adoption). Compared with physicians with fewer than 12 years of experience, those with more than 25 years of experience decreased use by an additional 23.0% (95% confidence interval -36.7% to -9.2%). The lowest rates of decline occurred in physicians specializing in vascular or thoracic surgery, for whom the procedures accounted for a large share of revenue. Physicians with high proportions of patients aged more than 80 years or with asymptomatic carotid stenosis were less likely to reduce their use of carotid revascularization.Conclusion Surgeons with more experience and the lowest share in carotid revascularization practice reduced their use of the procedure the most. These practice factors should be considered in quality improvement efforts when the evidence base evolves away from a specific treatment.

Perioperative outcomes after reoperative carotid endarterectomy are worse than expected

OBJECTIVE

Reoperative carotid endarterectomy (CEA) can be technically challenging because of significant scarring as a consequence of the initial CEA procedure. There are limited data that describe outcomes after reoperative CEA, and as such, our goal was to determine the effect of reoperative CEA on perioperative outcomes.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was queried for patients undergoing index and reoperative CEA between 2005 and 2014. Multivariate analysis was performed to assess the effect of reoperative CEA on outcomes including stroke, major adverse cardiovascular event, and procedure time.

RESULTS

There were 75,943 index and 140 reoperative CEAs identified. No differences were found in baseline demographics or comorbidities except that the reoperative group had a higher incidence of patients with end-stage renal disease (3.6% vs 1.1%; P = .004). Prior stroke with deficit (20.8% vs 15.4%; P = .137) and without deficit (11.5% vs 9.1%; P = .43) were similar between reoperative and index CEA groups. Both the reoperative and index initial CEA cohorts had comparable rates of surgical site infection (0.7% vs 0.3%; P = .462), return to the operating room (3.6% vs 4%; P = .816), readmission with 30 days (2.1% vs 6.9%; P = .810), myocardial infarction (2.1% vs 0.9%; P = .125), and perioperative death (0.7% vs 0.9%; P = .853). The reoperative cohort had a significantly higher rate of perioperative stroke (5.0% vs 1.6%; P = .002) and a longer operative duration (137 ± 54 vs 116 ± 49 minutes; P < .001). Multivariate analysis revealed that reoperative CEA was an independent factor for postoperative stroke (odds ratio, 3.71; 95% confidence interval [CI], 1.61-8.57; P = .002), major adverse cardiovascular event (odds ratio, 2.76; 95% CI, 1.32-5.78; P = .007), and longer procedure time (means ratio, 1.21; 95% CI, 1.12-1.30; P < .001).

CONCLUSIONS

Reoperative carotid surgery is associated with a longer operative time and higher risk for perioperative stroke compared with index CEA. This information informs the risk-benefit analysis for reoperation.

Development and validation of a score to predict life expectancy after carotid endarterectomy in asymptomatic patients

OBJECTIVE

Recent improvement of best medical treatment for carotid stenosis has sparked a debate on the role of surgery-identification of patients who may benefit from carotid endarterectomy (CEA) is crucial to avoid overtreatment. An expected 5-year postoperative survival is one of the main selection criteria. The aim of this study was the development of a score for predicting survival of asymptomatic patients after CEA.

METHODS

Our score was derived from a retrospective analysis of 648 consecutive asymptomatic patients from a single hospital. External validation of the score was then performed on a second cohort of 334 asymptomatic patients from two different hospitals in the same area. Factors associated with reduced postoperative survival within the derivation cohort (DC) were identified and tested for statistical significance. Each selected factor was assigned a score proportional to its β coefficient: 1 point for chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, and lack of statin treatment; 4 points for age 70 to 79 years and creatinine concentration ≥1.5 mg/dL; 8 points for age ≥80 years and dialysis. The DC was divided into four groups based on individual scores: group 1, 0 to 3 points; group 2, 4 to 7 points; group 3, 8 to 11 points; and group 4, ≥12 points. Group-specific survival curves were calculated. The validation cohort (VC) was stratified according to the score. Survival of each of the four risk groups within the VC was compared with its analogue from the DC.

RESULTS

Median follow-up of the DC and VC was, respectively, 56 and 65 months. Intercohort comparison of 5-year survival was 84.7% ± 1.7% vs 85.2% ± 2% (P = .41). Group-specific 5-year survival within the DC was 97% ± 1.5% (group 1), 88.4% ± 2.2% (group 2), 69.6% ± 4.7% (group 3), and 48.1% ± 13.5% (group 4; P < .0001). Five-year survival within the VC was 95.5% ± 2% (group 1), 89.5% ± 2.7% (group 2), 65% ± 6.1% (group 3), and 44.8% ± 14.1% (group 4; P < .0001). Intercohort comparison of group-specific survival curves showed close similarity throughout the groups.

CONCLUSIONS

Our score is a simple clinical tool that allows a quick and reliable prediction of survival in asymptomatic patients who are candidates for CEA. This selective approach is crucial to avoid unnecessary surgery on patients who are less likely to survive long enough to experience the benefits of this preventive procedure.

Meta-analysis of the costs of carotid artery stenting and carotid endarterectomy

BACKGROUND

Carotid artery stenting (CAS) is currently associated with an increased risk of 30-day stroke compared with carotid endarterectomy (CEA), whereas both interventions seem equally durable beyond the periprocedural period. Although the clinical outcomes continue to be scrutinized, there are few data summarizing the costs of both techniques.

METHODS

A systematic search was conducted in MEDLINE, Embase and Cochrane databases in August 2016 identifying articles comparing the costs or cost-effectiveness of CAS and CEA in patients with carotid artery stenosis. Combined overall effect sizes were calculated using random-effects models. The in-hospital costs were specified to gain insight into the main heads of expenditure associated with both procedures.

RESULTS

The literature search identified 617 unique articles, of which five RCTs and 12 cohort studies were eligible for analysis. Costs of the index hospital admission were similar for CAS and CEA. Costs of the procedure itself were 51 per cent higher for CAS, mainly driven by the higher costs of devices and supplies, but were balanced by higher postprocedural costs of CEA. Long-term cost analysis revealed no difference in costs or quality of life after 1 year of follow-up.

CONCLUSION

Hospitalization and long-term costs of CAS and CEA appear similar. Economic considerations should not influence the choice of stenting or surgery in patients with carotid artery stenosis being considered for revascularization.

Evolution of Practices in Carotid Surgery: Observational Study in France from 2006 to 2015

BACKGROUND

The principal objective of this study is to determine the evolution of surgical management of stenosis of carotid bifurcation over a period of 10 years in France. The secondary objective is to ascertain the impact of recommendations and of the literature on the evolution of these practices.

METHODS

From the registry of the "Agence Technique de l'Information sur l'Hospitalisation" we collected all the data for carotid surgery procedures carried out in French healthcare establishments between 2006 and 2015. The search was conducted using the common classification of medical procedures for open surgery and endovascular treatment, and diagnosis-related groups corresponding to neurovascular disease. We conducted a descriptive analysis of data year-by-year and analyzed the number of procedures, the evolution of the type of surgery according to the type of establishment, and the mean duration of hospital stays.

RESULTS

During the study period, 165,276 classical procedures (95.8%) and 7319 endovascular procedures (4.2%) of carotid bifurcation were performed. The overall number of procedures was stable over time at a mean of approximately 17,000 procedures per year. Concerning conventional surgery, eversion endarterectomy became the main technique from 2008 onwards, superseding open endarterectomy with patch closure, whereas direct primary closure of the carotid bifurcation has been declining steadily ever since. The use of a shunt declined steadily from 16.3% in 2006 to 13.3% in 2015. Endovascular treatment progressed steadily during the study period from 455 procedures (2.7% of procedures) in 2006 to 943 procedures (5.7%) in 2015. The mean hospital length of stay for patients without associated severe comorbidity was constant for classical surgery (mean of 5.4 days).

CONCLUSION

This observational analysis showed stability in the number of carotid procedures performed during the period and a progressive modification of carotid surgery practices in France, in accordance with the recommendations of learned societies and major publications.

The association of Carotid Revascularization Endarterectomy versus Stent Trial (CREST) and Centers for Medicare and Medicaid Services Carotid Guideline Publication on utilization and outcomes of carotid stenting among "high-risk" patients

OBJECTIVE

Since the 2004 approval by the United States Food and Drug Administration of carotid artery stenting (CAS), there have been two seminal publications about CAS reimbursement (Centers for Medicare and Medicaid Services guidelines; 2008) and clinical outcomes (Carotid Revascularization Endarterectomy versus Stent Trial [CREST]; 2010). We explored the association between these publications and national trends in CAS use among high-risk symptomatic patients.

METHODS

The most recent congruent data sets of the Nationwide Inpatient Sample (NIS) were queried for patients undergoing carotid revascularization. The sample was limited to include only patients who were defined as "high-risk" if they had a Charlson Comorbidity Score of ≥3.0. Subgroup analyses were performed of high-risk patients with symptomatic carotid stenosis. Utilization proportions of CAS were calculated quarterly from 2005 to 2011 for NIS. Three time intervals related to Centers for Medicare and Medicaid Services guidelines and CREST publication were selected: 2005 to 2008, 2008 to 2010, and after 2010. Logistic regression with piecewise linear trend for time was used to estimate different trends in CAS use for the overall high-risk sample and for neurologically asymptomatic and symptomatic cases. Multivariate logistic regression was used to compare odds of postoperative mortality and stroke between these two procedures at different time intervals independent of confounding variables.

RESULTS

During the study period, 20,079 carotid endarterectomies (CEAs) and 3447 CAS procedures were performed in high-risk patients in the NIS database. CAS utilization constituted 20.5% of carotid revascularization procedures among high-risk symptomatic patients, with a significant increase from 18.6% to 24.4% during the study period (P < .001). There was an initial increase during 2005 to 2008 in the rate of CAS compared with CEA, CAS utilization significantly decreased during 2008 to 2010 by a 3.3% decline in the odds ratio (OR) of CAS per quarter (OR, 0.967; 95% confidence interval [CI], 0.943-0.993; P = .002), and after CREST (after 2010), CAS utilization continued to increase significantly from the prepublication to the postpublication time interval. The odds of in-hospital mortality (OR, 2.56; 95% CI, 1.17-5.62; P = .019) and postoperative in-hospital stroke (OR, 1.53; 95% CI, 1.09-3.68; P = .024) were independently and significantly higher for CAS patients in the overall sample.

CONCLUSIONS

The use of CAS for carotid revascularization in a high-risk cohort of patients has significantly increased from 2005 to 2011. Compared with CEA, CAS independently increased the odds of perioperative in-hospital stroke in all high-risk patients and of in-hospital mortality in symptomatic high-risk patients.

Impact of Clinical Trial Results on the Temporal Trends of Carotid Endarterectomy and Stenting From 2002 to 2014

Supplemental Digital Content is available in the text.

Background and Purpose—

Randomized trials provide conflicting data for the efficacy of carotid-artery stenting compared with endarterectomy. The purpose of this study was to examine the impact of conflicting clinical trial publications on the utilization rates of carotid revascularization procedures.

Methods—

We conducted a population-level time-series analysis of all individuals who underwent carotid endarterectomy and stenting in Ontario, Canada (2002–2014). The primary analysis examined temporal changes in the rates of carotid revascularization procedures after publications of major randomized trials. Secondary analyses examined changes in overall and age, sex, carotid-artery symptom, and operator specialty–specific procedure rates.

Results—

A total of 16 772 patients were studied (14 394 endarterectomy [86%]; 2378 stenting [14%]). The overall rate of carotid revascularization decreased from 6.0 procedures per 100 000 individuals ≥40 years old in April 2002 to 4.3 procedures in the first quarter of 2014 (29% decrease; P<0.001). The rate of endarterectomy decreased by 36% (P<0.001), whereas the rate of carotid-artery stenting increased by 72% (P=0.006). We observed a marked increase (P=0.01) in stenting after publication of the SAPPHIRE trial (Stenting and Angioplasty With Protection in Patients at High Risk for Endarterectomy) in 2004, whereas stenting remained relatively unchanged after subsequent randomized trials published in 2006 (P=0.11) and 2010 (P=0.34). In contrast, endarterectomy decreased after trials published in 2006 (P=0.04) and 2010 (P=0.005).

Conclusions—

Although the overall rates of carotid revascularization and endarterectomy have fallen since 2002, the rate of carotid-artery stenting has risen since the publication of stenting-favorable SAPPHIRE trial. Subsequent conflicting randomized trials were associated with a decreasing rate of carotid endarterectomy.

Primary Angioplasty Versus Stenting for Endovascular Management of Intracranial Atherosclerotic Disease Following Acute Ischemic Stroke

BACKGROUND

The future of neuroendovascular treatment for intracranial atherosclerotic disease (ICAD) has been debated since the results of SAMMPRIS reflected poor outcomes following endovascular therapy. There is currently a large spectrum of current management strategies. We compared historical outcomes of patients with ICAD and stroke that were treated with angioplasty-alone versus stent placement.

METHODS

We extracted a population from the Nationwide Inpatient Sample (NIS) (2005-2011) and the National Inpatient Sample (NIS) (2012) composed of patients with ICAD and infarction that were admitted nonelectively and received endovascular revascularization. Patients treated with thrombectomy or thrombolysis were excluded. Categorical variables were compared with Chi-squared tests. Binary logistic regression was performed to evaluate mortality while controlling for age, sex, severity, and comorbidities.

RESULTS

About 2059 admissions met our criteria. A majority were treated via stent placement (71%). Angioplasty-alone had significantly higher mortality (17.6% vs. 8.4%, P<0.001), but no difference in iatrogenic stroke rate (3.4% vs. 3.6%, P=0.826), compared to stent placement. The adjusted odds ratio of mortality for stented patients was 0.536 (95% CI: 0.381-0.753, P<0.001) in comparison to patients treated with angioplasty alone.

CONCLUSIONS

This study found the risk of mortality to be elevated following angioplasty alone in comparison to revascularization with stent placement, without a corresponding significant difference in iatrogenic stroke rate. This may represent selection bias due to patient characteristics not defined in the database, but it also may indicate that patients with ICAD and acute stroke have increased odds of stenosis that is refractory to angioplasty alone and have a high risk of mortality without revascularization.

Trends, Predictors, and Outcomes of Stroke After Surgical Aortic Valve Replacement in the United States

BACKGROUND

Postoperative stroke is a devastating complication after aortic valve replacement (AVR). Our objective was to use a large national database to identify the incidence of and risk factors for stroke after AVR, as well as to determine incremental mortality, resource use, and cost of stroke.

METHODS

We identified 360,437 patients who underwent isolated surgical AVR between 1998 and 2011 from the National Inpatient Sample (NIH) database. Mean age was 66 ± 32 years. Multivariable regression and propensity matching were used to identify risk factors and the effect of stroke on outcomes. Patients were stratified according to the Elixhauser comorbidity score (ECS) into low- (0-5), medium- (6-15), and high-risk (16+) categories.

RESULTS

Stroke after AVR occurred in 5,092 (1.45%) patients. The incidence of stroke declined from 1.69% in 1999 to 0.94% in 2011 (p < 0.001). Increasing age and higher comorbidities were the main predictors of stroke (each p < 0.001). The highest-volume centers (>200 AVRs/y) had the lowest rate of stroke (1.2%). After multivariable adjustment, high-volume centers had lower odds of stroke in medium-risk (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.37-0.94) and high-risk patients (OR, 0.39; 95% CI, 0.22-0.68) compared with the lowest-volume centers. For low-risk patients, volume was not associated with stroke. Patients who experienced stroke were hospitalized for 4 days longer, had an average of $10,496 higher costs, and had 2.74 (95% CI, 1.97-3.80) times higher odds of in-hospital mortality compared with those who did not experience stroke (all p < 0.001).

CONCLUSIONS

The incidence of stroke after AVR has decreased but remains a significant cause of morbidity in medium- and high-risk patients. Superior outcomes can be achieved in medium- to high-risk patients at high-volume centers.

Physician specialty and variation in carotid revascularization technique selected for Medicare patients

OBJECTIVE

Carotid artery stenting (CAS) has become an alternative to carotid endarterectomy (CEA) for select patients with carotid atherosclerosis. We hypothesized that the choice of CAS vs CEA varies as a function of treating physician specialty, which would result in regional variation in the relative use of these treatment types.

METHODS

We used Medicare claims (2002-2010) to calculate annual rates of CAS and CEA and examined changes by procedure type over time. To assess regional preferences surrounding CAS, we calculated the proportion of revascularizations by CAS, across hospital referral regions, defined according to the Dartmouth Atlas of Healthcare. We then examined relationships between patient factors, physician specialty, and regional use of CAS.

RESULTS

The annual number of all carotid revascularization procedures decreased by 30% from 2002 to 2010 (3.2 to 2.3 per 1000; P = .005). Whereas rates of CEA declined by 35% during these 8 years (3.0 to 1.9 per 1000; P < .001), CAS utilization increased by 5% during the same interval (0.30 to 0.32 per 1000; P = .014). Variation in utilization of carotid revascularization varied across the Unites States, with some regions performing as few as 0.7 carotid procedure per 1000 beneficiaries (Honolulu, Hawaii) and others performing nearly 8 times as many (5.3 per 1000 in Houma, La). Variation in procedure type (CEA vs CAS) was evident as well, as the proportion of carotid revascularization procedures that were constituted by CAS varied from 0% (Casper, Wyo, and Meridian, Miss) to 53% (Bend, Ore). The majority of CAS procedures were performed by cardiologists (49% of all CAS cases), who doubled their rates of CAS during the study period from 0.07 per 1000 in 2002 to 0.15 per 1000 in 2010.

CONCLUSIONS

Variation in rates of carotid revascularization exists. Whereas rates of carotid revascularization have declined by more than 30% in recent years, utilization of CAS has increased. The proportion of all carotid revascularization procedures performed as CAS varies markedly by geographic region, and regions with the highest proportion of cardiologists perform the most CAS procedures. Evidence-based guidelines for carotid revascularization will require a multidisciplinary approach to ensure uniform adoption across specialties that care for patients with carotid artery disease.

The Association of Publication of Center for Medicaid and Medicare Services Guidelines for Carotid Artery Angioplasty and Stenting (CAS) and CREST Results on the Utilization of CAS in Carotid Revascularization

BACKGROUND

Since the 2004 approval of carotid artery angioplasty and stenting (CAS), there have been 2 seminal publications about CAS reimbursement (Center for Medicaid and Medicare Several guidelines [CMSG]; 2008) and clinical outcomes (Carotid Revascularization Endarterectomy versus Stent Trial [CREST]; 2010). We explored trends in CAS utilization after these publications nationally.

METHODS

The most recent datasets of the nationwide inpatient sample (NIS) was queried for patients undergoing carotid revascularization. Utilization proportions of CAS were calculated quarterly from 2005 to 2011 for NIS. Three-time intervals related to CMSG and CREST publication were selected 2005-2008, 2008-2010, and after 2010. Logistic regression with piecewise linear trend for time was used to estimate different trends in CAS utilization for overall samples and for neurologically asymptomatic and symptomatic cases.

RESULTS

The majority (95%) of the carotid revascularizations were performed on asymptomatic patients. Overall, CAS utilization constituted 12.5% of carotid revascularization procedures with a significant period increase of CAS; from 9.4% to 14%; P < 0.001. There was a small but significant decrease in the rate of CAS utilization after CMSG were published corresponding to a 2% decline in the odds ratio (OR) of CAS per quarter (OR, 0.98; 95% confidence interval, 0.97-0.99; P = 0.001). After CREST, CAS utilization continued to increase in both NIS but the rate of increase did not change significantly from the prepublication to the postpublication time interval. The odds of in-hospital mortality and postoperative stroke were independently and significantly higher for CAS patients in both overall and within the symptomatic cohorts. In all 3 periods of the study, and compared to carotid endarterectomy, the odds of mortality and postoperative stroke were significantly higher among patients who underwent CAS.

CONCLUSIONS

Although overall utilization of CAS increased since 2005, it was not uniformly associated by the publication of CMSG or CREST. Despite increased utilization, the odds of adverse outcomes were independently higher among CAS patients.

Readmissions after carotid artery revascularization in the Medicare population

BACKGROUND

In appropriately selected patients with severe carotid stenosis, carotid revascularization reduces ischemic stroke. Prior clinical research has focused on the efficacy and safety of carotid revascularization, but few investigators have considered readmission as a clinically important outcome.

OBJECTIVES

The aims of this study were to examine frequency, timing, and diagnoses of 30-day readmission following carotid revascularization; to assess differences in 30-day readmission between patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS); to describe hospital variation in risk-standardized readmission rates (RSRR); and to examine whether hospital variation in the choice of procedure (CEA vs. CAS) is associated with differences in RSRRs.

METHODS

We used Medicare fee-for-service administrative claims data to identify acute care hospitalizations for CEA and CAS from 2009 to 2011. We calculated crude 30-day all-cause hospital readmissions following carotid revascularization. To assess differences in readmission after CAS compared with CEA, we used Kaplan-Meier survival curves and fitted mixed-effects logistic regression. We estimated hospital RSRRs using hierarchical generalized logistic regression. We stratified hospitals into 5 groups by their proportional CAS use and compared hospital group median RSRRs.

RESULTS

Of 180,059 revascularizations from 2,287 hospitals, CEA and CAS were performed in 81.5% and 18.5% of cases, respectively. The unadjusted 30-day readmission rate following carotid revascularization was 9.6%. Readmission risk after CAS was greater than that after CEA. There was modest hospital-level variation in 30-day RSRRs (median: 9.5%; range 7.5% to 12.5%). Variation in proportional use of CAS was not associated with differences in hospital RSRR (range of median RSRR across hospital groups 9.49% to 9.55%; p = 0.771).

CONCLUSIONS

Almost 10% of Medicare patients undergoing carotid revascularization were readmitted within 30 days of discharge. Compared with CEA, CAS was associated with a greater readmission risk. However, hospitals' RSRR did not differ by their proportional CAS use.

Increased resource use in lung transplant admissions in the lung allocation score era

RATIONALE

In 2005, the lung allocation score (LAS) was implemented to prioritize organ allocation to minimize waiting-list mortality and maximize 1-year survival. It resulted in transplantation of older and sicker patients without changing 1-year survival. Its effect on resource use is unknown.

OBJECTIVES

To determine changes in resource use over time in lung transplant admissions.

METHODS

Solid organ transplant recipients were identified within the Nationwide Inpatient Sample (NIS) data from 2000 to 2011. Joinpoint regression methodology was performed to identify a time point of change in mean total hospital charges among lung transplant and other solid-organ transplant recipients. Two temporal lung transplant recipient cohorts identified by joinpoint regression were compared for baseline characteristics and resource use, including total charges for index hospitalization, charges per day, length of stay, discharge disposition, tracheostomy, and need for extracorporeal membrane oxygenation.

MEASUREMENTS AND MAIN RESULTS

A significant point of increased total hospital charges occurred for lung transplant recipients in 2005, corresponding to LAS implementation, which was not seen in other solid-organ transplant recipients. Total transplant hospital charges increased by 40% in the post-LAS cohort ($569,942 [$53,229] vs. $407,489 [$28,360]) along with an increased median length of stay, daily charges, and discharge disposition other than to home. Post-LAS recipients also had higher post-transplant use of extracorporeal membrane oxygenation (odds ratio, 2.35; 95% confidence interval, 1.56-3.55) and higher incidence of tracheostomy (odds ratio, 1.52; 95% confidence interval, 1.22-1.89).

CONCLUSIONS

LAS implementation is associated with a significant increase in resource use during index hospitalization for lung transplant.

Comparison of outcomes and utilization of extracranial-intracranial bypass versus intracranial stenting for intracranial stenosis

Background:

Extracranial–intracranial (EC-IC) bypass and intracranial stenting (ICS) are both revascularization procedures that have emerged as treatment options for intracranial atherosclerotic disease (ICAD). This study describes and compares recent trends in utilization and outcomes of intracranial revascularization procedures in the United States using a population-based cohort. It also investigates the association of ICS and EC-IC bypass with periprocedural morbidity and mortality, unfavorable discharge status, length of stay (LOS), and total hospital charges.

Methods:

The National Inpatient Sample (NIS) was queried for patients with ICAD who underwent EC-IC bypass or ICS during the years 2004–2010. Patient characteristics, demographics, perioperative complications, outcomes, and discharge data were collected.

Results:

There were 627 patients who underwent ICS and 249 patients who underwent EC-IC bypass. Patients who underwent ICS were significantly older (P < 0.001) with more comorbidities (P = 0.027) than those who underwent EC-IC bypass. Patients who underwent EC-IC bypass experienced higher rates of postprocedure stroke (P = 0.014), but those who underwent ICS experienced higher rates of death (P = 0.006). Among asymptomatic patients, the rates of postprocedure stroke (P = 0.341) and death (P = 0.887) were similar between patients who underwent ICS and those who underwent EC-IC bypass. Among symptomatic patients, however, there was a higher rate of postprocedure stroke in patients who underwent EC-IC bypass (P < 0.001) and a higher rate of death among patients who underwent ICS (P = 0.015).

Conclusion:

The ideal management of patients with ICAD cannot yet be defined. Although much data from randomized and prospective trials on revascularization have been collected, many questions remain unanswered. There still remain cohorts of patients, specifically patients who have failed aggressive medical management, where not enough evidence is available to dictate decision-making. In order to further elucidate the safety and efficacy of these intracranial revascularization procedures, further clinical trials are needed.

Impact of symptoms, gender, co-morbidities, and operator volume on outcome of carotid artery stenting (from the Nationwide Inpatient Sample [2006 to 2010])

The increase in the number of carotid artery stenting (CAS) procedures over the last decade has necessitated critical appraisal of procedural outcomes and patterns of utilization including cost analysis. The main objectives of our study were to evaluate the postprocedural mortality and complications after CAS and the patterns of resource utilization in terms of length of stay (LOS) and cost of hospitalization. We queried the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample from 2006 to 2010 using the International Classification of Diseases, Ninth Revision, procedure code of 00.63 for CAS. Hierarchical mixed-effects models were generated to identify the independent multivariate predictors of in-hospital mortality, procedural complications, LOS, and cost of hospitalization. A total of 13,564 CAS procedures (weighted n = 67,344) were analyzed. The overall postprocedural mortality was low at 0.5%, whereas the complication rate was 8%, both of which remained relatively steady over the time frame of the study. Greater postoperative mortality and complications were noted in symptomatic patients, women, and those with greater burden of baseline co-morbidities. A greater operator volume was associated with a lower rate of postoperative mortality and complications, as well as shorter LOS and lesser hospitalization costs. In conclusion, the postprocedural mortality after CAS has remained low over the recent years. Operator volume is an important predictor of postprocedural outcomes and resource utilization.

The impact of patient age and comorbidities on the occurrence of "never events" in cerebrovascular surgery: an analysis of the Nationwide Inpatient Sample

OBJECT

As health care administrators focus on patient safety and cost-effectiveness, methodical assessment of quality outcome measures is critical. In 2008 the Centers for Medicare and Medicaid Services (CMS) published a series of "never events" that included 11 hospital-acquired conditions (HACs) for which related costs of treatment are not reimbursed. Cerebrovascular procedures (CVPs) are complex and are often performed in patients with significant medical comorbidities.

METHODS

This study examines the impact of patient age and medical comorbidities on the occurrence of CMS-defined HACs, as well as the effect of these factors on the length of stay (LOS) and hospitalization charges in patients undergoing common CVPs.

RESULTS

The HACs occurred at a frequency of 0.49% (1.33% in the intracranial procedures and 0.33% in the carotid procedures). Falls/trauma (n = 4610, 72.3% HACs, 357 HACs per 100,000 CVPs) and catheter-associated urinary tract infections (n = 714, 11.2% HACs, 55 HACs per 100,000 CVPs) were the most common events. Age and the presence of ≥ 2 comorbidities were strong independent predictors of HACs (p < 0.0001). The occurrence of HACs negatively impacts both LOS and hospital costs. Patients with at least 1 HAC were 10 times more likely to have prolonged LOS (≥ 90th percentile) (p < 0.0001), and 8 times more likely to have high inpatient costs (≥ 90th percentile) (p < 0.0001) when adjusting for patient and hospital factors.

CONCLUSIONS

Improved quality protocols focused on individual patient characteristics might help to decrease the frequency of HACs in this high-risk population. These data suggest that risk adjustment according to underlying patient factors may be warranted when considering reimbursement for costs related to HACs in the setting of CVPs.