Most patients experiencing 30-day postoperative stroke after carotid endarterectomy will initially experience disability

Cost-Effectiveness of Screening Asymptomatic Carotid Stenosis by Atherosclerotic Cardiovascular Risk

Importance

Extracranial internal carotid artery stenosis (50-99% arterial narrowing) is an important risk factor for ischemic stroke. Yet, the benefits and harms of targeted screening for asymptomatic carotid artery stenosis (ACAS) have not been assessed in population-based studies.

Objective

To estimate the cost-effectiveness of one-time, targeted ACAS screening stratified by atherosclerotic cardiovascular disease (ASCVD) risk using the American Heart Association's Pooled Cohort Equations.

Design Setting and Participants

We developed a lifetime microsimulation model of ACAS and stroke for a hypothetical cohort representative of US adults aged 50-80 years without stroke history. We used the Cardiovascular Health Study to estimate the probability and severity of ACAS based on individual characteristics (e.g., age, sex, smoking status, blood pressure, and cholesterol). Stroke risks were functions of these characteristics and ACAS severity. In the model, individuals testing positive for >70% stenosis with Duplex ultrasound and a confirmatory diagnostic test undergo revascularization, which may reduce the risk of stroke but also introduces complication risks. Diagnostic performance parameters, revascularization benefits and risks, utility weights, and costs were estimated from published sources. Cost-effectiveness was assessed from the health care sector perspective using a $100,000/quality-adjusted life year (QALY) threshold.

Main Outcomes and Measures

Estimated stroke events prevented, lifetime costs, QALYs, and incremental cost-effectiveness ratios (ICERs) associated with ACAS screening. Costs (2023 USD) and QALYs were discounted at 3% annually.

Results

We found that screening individuals with a 10-year ASCVD risk >30% was the most cost-effective strategy, with an ICER of $89,000/QALY. This strategy would make approximately 11.9% of the population eligible for screening, averting an estimated 24,084 strokes. Results were sensitive to variations in the efficacy and complication risk of revascularization. In probabilistic sensitivity analysis, screening those in lower ASCVD risk groups (0-20%) only had a 0.6% chance of being cost-effective.

Conclusion and Relevance

A one-time screening may only be cost-effective for adults at a relatively high ASCVD risk. Our findings provide a framework that can be adapted as future clinical trial data continue to improve our understanding of the role of revascularization and intensive medical therapy in contemporary stroke prevention secondary to carotid disease.

Perioperative stroke

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.

Risk factors for postoperative acute ischemic stroke in advanced-aged patients with previous stroke undergoing noncardiac surgery: a retrospective cohort study

BACKGROUND

The current study aimed to investigate the incidence and risk factors for postoperative acute ischemic stroke (PAIS) in advanced-aged patients (≥ 75 years) with previous ischemic stroke undergoing noncardiac surgery.

METHODS

In this single-center retrospective cohort study, all advanced-aged patients underwent noncardiac surgery from 1 January, 2019, to 30 April, 2022. Data were extracted from hospital electronic medical records. Multivariable logistic regression analysis was performed to determine predictors of PAIS. Multivariable linear or logistic regression analysis was performed to determine predictors of outcomes due to PAIS.

RESULTS

Twenty-four patients (6.0%) of the 400 patients developed PAIS. Carotid endarterectomy (CEA), length of surgery and preoperative Modified Rankin scale (mRS) ≥ 3 were significant predictors of PAIS. CEA was associated with increased risk of PAIS (OR 4.14; 95%CI, 1.43-11.99). Each additional minute in length of surgery had slightly increased the risk of PAIS (OR, 1.01; 95%CI, 1.00-1.01). Compared with reference (mRS < 3), mRS ≥ 3 increased odds of PAIS (OR, 4.09;95%CI, 1.12-14.93). Surgery type and length of surgery were found to be significant predictors of in-hospital expense (P < 0.001) and hospital stays (P < 0.05).

CONCLUSIONS

CEA, length of surgery and preoperative mRS ≥ 3 may increase the development of PAIS in advanced-aged patients (≥ 75 years) with previous stroke undergoing noncardiac surgery. PAIS increased in-hospital mortality and prolonged hospital stay.

Postoperative Disability and One-Year Outcomes for Patients Suffering a Stroke after Carotid Endarterectomy

OBJECTIVES

Although post-carotid endarterectomy (CEA) strokes are rare, they can be devastating. The degree of disability that patients develop after such events and its effects on long-term outcomes are unclear. Our goal was to assess the extent of postoperative disability in patients suffering strokes after CEA and evaluate its association with long-term outcomes.

METHODS

The Vascular Quality Initiative CEA registry (2016-2020) was queried for CEAs performed for asymptomatic or symptomatic indications in patients with preoperative modified Rankin Scale (mRS) scores of 0-1. The mRS grades stroke-related disability as 0 (none), 1 (not significant), 2-3 (moderate), 4-5 (severe), and 6 (dead). Patients suffering postoperative strokes with recorded mRS scores were included. Postoperative stroke-related disability based on mRS and its association with long-term outcomes were analyzed.

RESULTS

Among 149,285 patients undergoing CEA, there were 1,178 patients without preoperative disability who had postoperative strokes and reported mRS scores. Mean age was 71 ± 9.2 years and 59.6% of patients were male. Regarding ipsilateral cortical symptoms within six months preoperatively, 83.5% of patients were asymptomatic, 7.3% had transient ischemic attacks, and 9.2% had strokes. Postoperative stroke-related disability was classified as mRS 0 (11.6%), 1 (19.5%), 2-3 (29.4%), 4-5 (31.5%), and 6 (8%). One-year survival stratified by postoperative stroke-related disability was 91.4% for mRS 0, 95.6% for mRS 1, 92.1% for mRS 2-3, and 81.5% for mRS 4-5 (P<.001). Multivariable analysis demonstrated that while severe postoperative disability was associated with increased death at one year (HR 2.97, 95% CI 1.5-5.89, P=.002), moderate postoperative disability had no such association (HR .95, 95% CI .45-2, P=.88). One-year freedom from subsequent ipsilateral neurological events or death stratified by postoperative stroke-related disability was 87.8% for mRS 0, 93.3% for mRS 1, 88.5% for mRS 2-3, and 77.9% for mRS 4-5 (P<.001). Severe postoperative disability was independently associated with increased ipsilateral neurological events or death at one year (HR 2.34, 95% CI 1.25-4.38, P=.01). However, moderate postoperative disability exhibited no such association (HR .92, 95% CI .46-1.82, P=.8).

CONCLUSIONS

The majority of patients without preoperative disability who suffered strokes after CEA developed significant disability. Severe stroke-related disability was associated with higher one-year mortality and subsequent neurological events. These data can improve informed consent for CEA and guide prognostication after postoperative strokes.

Does modified Rankin Score (mRS) matter? The impact of stroke severity on carotid artery endarterectomy (CEA) outcomes

AIMS

Carotid artery endarterectomy (CEA) is recommended to reduce stroke risk in patients following non-disabling ischaemic stroke (modified Rankin Score mRS<3). We reviewed CEA outcomes in patients after more devastating strokes (mRS≥3).

METHODS

An observational cohort study was performed, and data was collected from 1013 CEA cases over fifteen years. Patient demographics, co-morbidities and post-operative outcomes were compared between preoperative mRS<3 (Group one) and mRS≥3 (Group two). Statistical significance was determined by p<0.05.

RESULTS

Ninety-one (9%) patients were mRS ≥ 3. There was no significant difference between age, gender, and operated side. Group two had significantly higher rates of diabetes and frailty. There was no significant difference in anaesthetic type. Group two spent longer in High Dependency. Return to theatre and post-operative complications were similar. Incidence of perioperative stroke, mortality and readmission rates were not significant at 30 days post-operation between the two groups.

CONCLUSION

Patients with a higher mRS have more pre-operative co-morbidities but short-term perioperative complication rate is not significantly different. Patient selection should be undertaken with care.

Unplanned Shunting Is Associated with Higher Stroke Risk after Eversion Carotid Endarterectomy

BACKGROUND

Shunting during eversion carotid endarterectomy (eCEA) may be technically challenging. Whether shunting practice patterns modify perioperative stroke risk after eCEA is unclear. We aimed to compare eCEA outcomes based on shunting practice.

METHODS

The Vascular Quality Initiative (2011-2019) was queried for eCEAs performed for symptomatic and asymptomatic carotid stenosis. Univariable and multivariable analyses compared outcomes based on whether shunting was routine practice, preoperatively-indicated, intraoperatively-indicated, or not performed.

RESULTS

There were 13,207 eCEAs identified. Average age was 71.4 years and 59.4% of patients were male sex. Ipsilateral carotid stenosis was >80% in 45.6% and there was severe contralateral carotid stenosis in 8.6%. Early ipsilateral symptoms within 14 days of eCEA were transient ischemic attack in 5.6% and stroke in 7%. The majority of cases were performed under general anesthesia (82.7%). Electroencephalogram monitoring and stump pressures were utilized in 30.9% and 14.7%, respectively. Shunting was routine (25.4%), preoperatively-indicated (1.9%), intraoperatively-indicated (4.7%), or not implemented (68%). Preoperatively-indicated shunting was more often performed in patients with early symptomatic carotid stenosis or severe contralateral carotid stenosis. After routine shunting, preoperatively-indicated shunting, intraoperatively-indicated shunting, and no shunting, median operative duration was 110, 101, 112, and 97 min, respectively (P < 0.001), and ipsilateral perioperative stroke prevalence was 0.6%, 1.2%, 1.9%, and 0.7%, respectively (P = 0.004). On multivariable analysis, longer operative time was associated with routine shunting (MR 1.17, 95% CI 1.15-1.19, P < 0.001), preoperatively-indicated shunting (MR 1.09, 95% CI 1.04-1.15, P < 0.001), and intraoperatively-indicated shunting (MR 1.12, 95% CI 1.09-1.16, P < 0.001) compared with no shunting. Compared with no shunting, routine shunting (OR 0.91, 95% CI 0.54-1.54, P = 0.74) and preoperatively-indicated shunting (OR 1.53, 95% CI 0.47-4.99, P = 0.48) were not associated with stroke; however, intraoperatively-indicated shunting was associated with increased stroke (OR 2.74, 95% CI 1.41-5.3, P = 0.003). Shunting type was not associated with perioperative mortality.

CONCLUSIONS

Intraoperatively-indicated shunting during eCEA was associated with longest operative duration and increased perioperative stroke risk. Surgeon familiarity with shunting and planning to shunt in advance may permit more expeditious shunting and prevent stroke.

Selective Nonoperative and Delayed Management of Severe Asymptomatic Carotid Artery Stenosis

OBJECTIVES

Although intervention is generally the standard of care for severe (80-99%) asymptomatic carotid stenosis, conservative management may be appropriate for a subset of patients. Our goal was to assess reasons for and outcomes of nonoperative/delayed operative management of asymptomatic severe carotid stenosis.

METHODS

Institutional vascular laboratory data from 2010 to 2018 was queried for all patients who underwent a carotid duplex ultrasonography. Patients with severe asymptomatic carotid stenosis (80-99%) were included. Such stenosis was defined by an end diastolic velocity >140 cm/sec on duplex ultrasound in patients without transient ischemic attacks (TIA)/strokes ≤6 months prior to imaging. Nonoperative/delayed operative management was defined as not undergone carotid endarterectomy (CEA) or carotid artery stent (CAS) ≤6 months after imaging. Reasons for nonoperative management or delayed intervention as well as subsequent TIA/stroke and survival were determined. Kaplan-Meier analysis was performed to evaluate survival.

RESULTS

Among 211 patients with severe carotid stenosis, 35 (16.6%) were managed nonoperatively or with delayed operation. Mean age in this subset was 72.6 ± 11.4 years and the majority were female (57.1%), had a smoking history (74.3%), and were on statins (91.4%) at the time of index duplex ultrasound. Reasons for no/delayed intervention were classified as severe medical comorbidities (37.1%), advanced age (17.1%), no referral for intervention (14.3%), patient refusal (14.3%), other severe concomitant cerebrovascular disease (11.4%), and active/advanced cancer (5.7%). Over a median follow-up of 35.2 months, no patients experienced TIAs/strokes attributable to carotid stenosis. One patient had a multifocal bilateral stroke after a cardiac arrest and prolonged resuscitation. A subset of patients underwent delayed CEA (8.6%) or CAS (2.9%). Four-year survival after initial imaging was 79%.

CONCLUSIONS

Reasons for nonoperative and delayed operative management in our cohort of asymptomatic carotid stenosis were commonly due to comorbidities and advanced age. However, a subset of patients was never referred to vascular surgeons/interventionalists. Adverse neurologic events due to carotid stenosis were not observed during follow-up and patients had relatively high long-term survival.

Hospital-Level Medicaid Prevalence Is Associated with Increased Length of Stay after Asymptomatic Carotid Endarterectomy and Stenting Despite no Increase in Major Complications

BACKGROUND

Length of stay (LOS) after carotid endarterectomy (CEA) and carotid artery stenting (CAS) for asymptomatic disease is used as a quality measure and affects hospital operating margins. Patient-level Medicaid status has traditionally been associated with longer hospital LOS. Our goal was to assess the association between hospital-level Medicaid prevalence and postoperative LOS after CEA and CAS.

METHODS

The National Inpatient Sample was queried from 2006-2014 for CEA and CAS performed for asymptomatic carotid stenosis. Overall hospital-level Medicaid prevalence was divided into quartiles. The quartiles were further categorized into low Medicaid prevalence (LM) (lowest quartile), medium Medicaid prevalence (MM) (second and third quartiles), and high Medicaid prevalence (HM) (fourth quartile) cohorts. The primary outcome evaluated was postoperative LOS >1 day. The secondary outcomes included perioperative/in-hospital complications and mortality.

RESULTS

There were 984,283 patients with asymptomatic carotid stenosis who underwent CEA (88%) or CAS (12%). Mean postoperative LOS after CEA at hospitals with LM, MM, and HM prevalence was 1.4 ± 1.5, 2.1 ± 2.5, and 2.2 ± 2.8 days (P = 0.0001), respectively, and after CAS were 1.7 ± 2.6, 1.8 ± 2.1, and 2 ± 2.6 days (P < 0.0001), respectively. After CEA, relative to LM prevalence, MM (OR 1.62, 95% CI 1.17-2.24) and HM (OR 1.66, 95% CI 1.2-2.28) prevalence were associated with a higher likelihood of LOS > 1 day (P = 0.009). After CAS, relative to LM prevalence, HM prevalence was associated with a higher likelihood of LOS >1 day (OR 1.42, 95% CI 1.06-1.91) (P = 0.003). After CEA, neurologic (0.8% vs. 0.9% vs. 0.9%, P = 0.83) and cardiac complications (0.9% vs. 1.2% vs. 1.2%, P = 0.24) were similar among hospitals with LM, MM, and HM prevalence, respectively. After CAS, the prevalence of neurological (1.1% vs. 1% vs. 1.2%, P = 0.42) and cardiac complications (2% vs. 1.3% vs. 1.5%, P = 0.46) were also similar. After both CEA and CAS, mortality was similar among Medicaid prevalence cohorts.

CONCLUSIONS

Higher hospital-level Medicaid prevalence was associated with longer LOS after CEA and CAS for asymptomatic carotid stenosis. Value-based payment models should adjust for hospital-level Medicaid prevalence to appropriately reimburse providers and hospital with higher Medicaid prevalence as well as investigate care pathways and systems improvement to help reduce LOS.

Natural History of Non-operative Management in Asymptomatic Patients with 70%-80% Internal Carotid Artery Stenosis by Duplex Criteria

OBJECTIVE

Treatment of asymptomatic internal carotid artery (ICA) stenosis, particularly for moderate to severe (70%-80%) disease, is controversial. The goal was to assess the clinical course of patients with moderate to severe carotid stenosis.

METHODS

A single institution retrospective analysis of patients with asymptomatic ICA stenosis identified on duplex ultrasound as moderate to severe (70%-80%) from 2003 to 2018 were analysed. Duplex criteria for 70%-80% stenosis was a systolic velocity of ≥325 cm/s or an ICA:common carotid artery ratio of ≥4, and an end diastolic velocity of <140 cm/s. Asymptomatic status was defined as no stroke/transient ischaemic attack (TIA) within six months of index duplex. Primary outcomes were progression of stenosis to >80%, ipsilateral stroke/TIA without documented progression, and death.

RESULTS

In total, 206 carotid arteries were identified in 182 patients meeting the inclusion criteria. Mean patient age was 71.5 years, 57.7% were male, and 67% were white. There were 19 stenoses removed from analysis except for survival analysis as they initially underwent carotid endarterectomy or carotid artery stent based on surgeon/patient preference. Documented progression occurred in 24.1% of stenoses. There were 5.3% of stenoses associated with an ipsilateral stroke/TIA without documented progression, which occurred at a mean of 26.4 months. Kaplan-Meier analysis demonstrated a 60.3% five year freedom from stenosis progression, 92.5% five year freedom from stroke/TIA without documented progression, and 83.7% five year survival. Risk factors associated with stroke/TIA without documented progression at five years were atrial fibrillation (hazard ratio [HR] 14.87, 95% confidence interval [CI] 2.72-81.16; p = .002) and clopidogrel use at index duplex (HR 6.19, 95% CI 1.33-28.83; p = .020). Risk factors associated with death at five years were end stage renal disease (HR 9.67, 95% CI 2.05-45.6; p = .004), atrial fibrillation (HR 7.55, 95% CI 2.48-23; p < .001), prior head/neck radiation (HR 6.37, 95% CI 1.39-29.31; p = .017), non-obese patients (HR 5.49, 95% CI 1.52-20; p = .009), and non-aspirin use at index duplex (HR 3.05, 95% CI 1.12-8.33; p = .030).

CONCLUSION

Patients with asymptomatic moderate to severe carotid stenosis had a low rate of stroke/TIA without documented progression. However, there was a high rate of stenosis progression reinforcing the need to follow these patients closely.

Shunt intention during carotid endarterectomy in the early symptomatic period and perioperative stroke risk

OBJECTIVE

Whether recent stroke mandates planned shunting during carotid endarterectomy (CEA) is controversial. Our goal was to determine associations of various shunting practices with postoperative outcomes of CEAs performed after acute stroke.

METHODS

The Vascular Quality Initiative database (2010-2018) was queried for CEAs performed within 14 days of an ipsilateral stroke. Surgeons who prospectively planned to shunt either shunted routinely per their usual practice or shunted selectively for preoperative indications. Surgeons who prospectively planned not to shunt either shunted selectively for intraoperative indications or did not shunt. Univariable and multivariable analyses compared shunting approaches.

RESULTS

There were 5683 CEAs performed after acute ipsilateral stroke. Surgeons planned to shunt in 56.1% of cases. Patients whose surgeons planned to shunt vs planned not to shunt were more likely to have severe contralateral stenosis (8.8% vs 6.9%; P = .008), to receive general anesthesia (97.5% vs 89.1%; P < .001), and to undergo conventional CEA (94% vs 81.8%; P < .001). Unadjusted outcomes were similar between the cohorts for operative duration (124.3 ± 48.1 minutes vs 123.6 ± 47 minutes; P = .572) and 30-day stroke (3.4% vs 3%; P = .457), myocardial infarction (1.1% vs 0.8%; P = .16), and mortality (1.6% vs 1.3%; P = .28). On multivariable analysis, planning to shunt vs planning not to shunt was associated with similar risk of 30-day stroke (odds ratio [OR], 1.17; 95% confidence interval [CI], 0.82-1.67; P = .402). On subgroup analysis, in 38.4% patients, no shunt was placed, whereas the remainder received routine shunts (44.4%), preoperatively indicated shunts (11.6%), and intraoperatively indicated shunts (5.5%). Compared with no shunting, shunting by surgeons who routinely shunt was associated with a similar stroke risk (OR, 1.39; 95% CI, 0.91-2.13; P = .129), but shunting by surgeons who selectively shunt on the basis of preoperative indications (OR, 2.11; 95% CI, 1.22-3.63; P = .007) or intraoperative indications (OR, 3.34; 95% CI, 1.86-6.01; P < .001) was associated with increased stroke risk. Prior coronary revascularization independently predicted increased intraoperatively indicated shunting (OR, 1.37; 95% CI, 1.05-1.8; P = .022).

CONCLUSIONS

In CEAs performed after acute ipsilateral stroke, there is no difference in postoperative stroke risk when surgeons prospectively plan to shunt or not to shunt. Shunting is often not necessary; however, when shunting is performed, routine shunters achieve better outcomes.