Contralateral Occlusion and Concomitant Procedures Drive Risk of Non-ipsilateral Stroke After Carotid Endarterectomy

Editor's Choice - Safety of Shunting Strategies During Carotid Endarterectomy: A Vascular Quality Initiative Data Analysis

OBJECTIVE

This study aimed to evaluate in hospital outcomes after carotid endarterectomy (CEA) according to shunt usage, particularly in patients with contralateral carotid occlusion (CCO) or recent stroke. Data from CEAs registered in the Vascular Quality Initiative database between 2012 and 2020 were analysed, excluding surgeons with < 10 CEAs registered in the database, concomitant procedures, re-interventions, and incomplete data.

METHODS

Based on their rate of shunt use, participating surgeons were divided in three groups: non-shunters (< 5%), selective shunters (5 - 95%), and routine shunters (> 95%). Primary outcomes of in hospital stroke, death, and stroke and death rate (SDR) were analysed in symptomatic and asymptomatic patients.

RESULTS

A total of 113 202 patients met the study criteria, of whom 31 147 were symptomatic and 82 055 were asymptomatic. Of the 1 645 surgeons included, 12.1% were non-shunters, 63.6% were selective shunters, and 24.3% were routine shunters, with 10 557, 71 160, and 31 579 procedures in each group, respectively. In the univariable analysis, in hospital stroke (2.0% vs. 1.9% vs. 1.6%; p = .17), death (0.5% vs. 0.4% vs. 0.4%; p = .71), and SDR (2.2% vs. 2.1% vs. 1.8%; p = .23) were not statistically significantly different among the three groups in the symptomatic cohort. The asymptomatic cohort also did not show a statistically significant difference for in hospital stroke (0.9% vs. 1.0% vs. 0.9%; p = .55), death (0.2% vs. 0.2% vs. 0.2%; p = .64), and SDR (1.0% vs. 1.1% vs. 1.0%; p = .43). The multivariable model did not show a statistically significant difference for the primary outcomes between the three shunting cohorts. On subgroup analysis, the SDRs were not statistically significantly different for patients with CCO (3.3% vs. 2.5% vs. 2.4%; p = .64) and those presenting with a recent stroke (2.9% vs. 3.4% vs. 3.1%; p = .60).

CONCLUSION

No statistically significant differences were found between three shunting strategies for in hospital SDR, including in patients with CCO or recent stroke.

Carotid Endarterectomy With Simultaneous Proximal Common Carotid Endovascular Intervention is Beneficial for Symptomatic Stenosis and Likely Confers No Advantage for Asymptomatic Lesions

INTRODUCTION

Carotid bifurcation stenosis may co-exist simultaneously with more proximal common carotid artery (CCA) atherosclerotic plaquing, primarily at the vessel origin in the aortic arch. This scenario is relatively infrequent and its' management does not have quality randomized data to support medical vs surgical treatment. It is logical to treat any high grade common carotid lesions proximal to a carotid bifurcation endarterectomy (CEA) site both to prevent perioperative emboli or thrombosis as well as future embolization. Prior long-term investigations of the combined treatment paradigm have been low volume analysis. Further, prior studies focus on perioperative outcomes with respect to stroke prevention. The only prior VQI study investigating mid-term outcomes following simultaneous CEA with proximal CCA endovascular therapy provided data on less than 10 patients beyond 1.5 years. The long-term follow-up (LFTU) component initiative within VQI has been emphasized in recent years, now allowing for much more robust LTFU analysis.

METHODS

Four cohorts were created for perioperative outcome analysis and Kaplan Meier freedom from event analysis: CEA in isolation for asymptomatic disease; CEA in isolation for symptomatic patients; CEA with proximal CCA endovascular intervention for asymptomatic; and, CEA with proximal CCA intervention for symptomatic patients. Binary logistic multivariable regression was performed for perioperative neurological event and 90-day mortality risk determination and Cox multivariable regression analysis was performed for long term freedom from cumulative ischemic neurological event and long-term mortality analysis. Symptomatology and type of surgery (CEA with or without CCA intervention) were individual variables in the multivariable analysis. Neurological ischemic event in this study encompassed transient ischemic attack (TIA) and stroke combined.

RESULTS

We noted a statistically significant (P < .001) escalation in rates of perioperative neurological event, myocardial infarction (MI), carotid re-exploration, 90 day mortality and combined neurological event and 90 day mortality moving from: A) asymptomatic CEA in isolation to B) symptomatic CEA in isolation to C) asymptomatic CEA combined with proximal CCA intervention to D) symptomatic CEA in combination with proximal CCA intervention. The positivity rate for the combined outcome of perioperative ischemic neurological event and 90 day mortality was 2.2% amongst asymptomatic CEA in isolation, 4.1% amongst symptomatic CEA in isolation, 4.4% amongst asymptomatic CEA in combination with proximal CCA intervention; and 8.8% in patients with symptomatic lesions undergoing combined CEA with proximal CCA intervention. On multivariable analysis patients undergoing CEA with proximal CCA endovascular intervention experienced greater risk for perioperative neurological ischemic event (aOR 2.03, 1.43-2.90, P < .001), combined perioperative neurological ischemic event and 90 day mortality (aOR 2.13, 1.62-2.80, P < .001), long term mortality (HR 1.62, 1.12-2.29, P < .001), and cumulative neurological ischemic event in long term follow up (HR 1.62, 1.12-2.29, P = .007). Amongst 4395 cumulative ischemic neurological events in all study patients, 34% were TIA.

CONCLUSIONS

Carotid bifurcation endarterectomy in combination with proximal endovascular common carotid artery intervention caries an over two fold higher perioperative risk of neurologic ischemic event and 90 day mortality relative to CEA in isolation for asymptomatic and symptomatic cohorts respectively. After surgery, freedom from cerebral ischemia and mortality for patients undergoing dual intervention is closely aligned with patients undergoing CEA in isolation. Despite high adverse perioperative event rates for the combined CEA and CCA treatment, there is likely long term stroke reduction and mortality benefit to this approach in symptomatic patients based on the event free rates seen herein after initial hospital discharge. The benefit of treating asymptomatic tandem ICA and CCA lesions remains vague but the 4.4% perioperative neurologic event and death rate suggests that these patients would be better managed with medical therapy.

Carotid Artery Stenting for Patients With Carotid Stenosis and Contralateral Carotid Artery Occlusion: A 12-Year Experience

BACKGROUND

Carotid artery stenting (CAS) has emerged as a potential alternative for treating patients with extracranial cerebrovascular diseases. Contralateral carotid artery occlusion (CCO) occurs in approximately 2.3% to 25% of patients with carotid artery stenosis. However, the association of a CCO with long-term outcomes after CAS remains unclear. Here, we aimed to evaluate the perioperative and long-term recovery and safety of patients with CCO after receiving CAS.

METHODS

We retrospectively collected the data of patients with CCO treated with CAS between 2010 and 2021. The primary end point was a nonfatal major stroke. The secondary end points included cerebral hemorrhage, nonfatal myocardial infarction, restenosis, acute renal insufficiency, stent-related complications, and death. Long-term outcomes were analyzed by Kaplan-Meier survival analysis using the following variables: symptomatic carotid stenosis, age, stent type, collateral flow status, and postdilation.

RESULTS

Seventy one consecutive patients with CCO who underwent CAS were included in the study. Of these, 61 patients (86%) were followed up for 9-134 months, with an average of 63.3 ± 30.4 months. In the perioperative period, 2 patients (2.8%) experienced stroke and 1 patient (1.4%) died due to cerebral hemorrhage combined with cerebral hernia. During follow-up, 2 patients (3.3%) developed stroke at 4 and 6 months each after CAS and 6 patients (9.8%) died (2 patients died due to myocardial infarction and 4 patients died due to either severe liver failure, car accident, cervical fracture, or unknown cause). Kaplan-Meier survival analysis showed that symptomatic carotid stenosis, age, stent type, and postdilation were not associated with long-term stroke (P＜0.05). The inadequate collateral flow group showed a higher stroke rate than the control group (P = 0.009).

CONCLUSIONS

CAS is a safe and effective therapy for patients with CCO. Inadequate collateral flow is associated with a higher long-term rate of stroke. Our findings revealed that symptomatic carotid stenosis, age, stent type, and postdilation had no significant effect on outcome events after CAS.

External Validation of Risk Prediction Models to Improve Selection of Patients for Carotid Endarterectomy

BACKGROUND AND PURPOSE

The net benefit of carotid endarterectomy (CEA) is determined partly by the risk of procedural stroke or death. Current guidelines recommend CEA if 30-day risks are <6% for symptomatic stenosis and <3% for asymptomatic stenosis. We aimed to identify prediction models for procedural stroke or death after CEA and to externally validate these models in a large registry of patients from the United States.

METHODS

We conducted a systematic search in MEDLINE and EMBASE for prediction models of procedural outcomes after CEA. We validated these models with data from patients who underwent CEA in the American College of Surgeons National Surgical Quality Improvement Program (2011-2017). We assessed discrimination using C statistics and calibration graphically. We determined the number of patients with predicted risks that exceeded recommended thresholds of procedural risks to perform CEA.

RESULTS

After screening 788 reports, 15 studies describing 17 prediction models were included. Nine were developed in populations including both asymptomatic and symptomatic patients, 2 in symptomatic and 5 in asymptomatic populations. In the external validation cohort of 26 293 patients who underwent CEA, 702 (2.7%) developed a stroke or died within 30-days. C statistics varied between 0.52 and 0.64 using all patients, between 0.51 and 0.59 using symptomatic patients, and between 0.49 to 0.58 using asymptomatic patients. The Ontario Carotid Endarterectomy Registry model that included symptomatic status, diabetes, heart failure, and contralateral occlusion as predictors, had C statistic of 0.64 and the best concordance between predicted and observed risks. This model identified 4.5% of symptomatic and 2.1% of asymptomatic patients with procedural risks that exceeded recommended thresholds.

CONCLUSIONS

Of the 17 externally validated prediction models, the Ontario Carotid Endarterectomy Registry risk model had most reliable predictions of procedural stroke or death after CEA and can inform patients about procedural hazards and help focus CEA toward patients who would benefit most from it.