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

Stroke risk management in carotid atherosclerotic disease: a clinical consensus statement of the ESC Council on Stroke and the ESC Working Group on Aorta and Peripheral Vascular Diseases

Carotid atherosclerotic disease continues to be an important cause of stroke, often disabling or fatal. Such strokes could be largely prevented through optimal medical therapy and carotid revascularization. Advancements in discovery research and imaging along with evidence from recent pharmacology and interventional clinical trials and registries and the progress in acute stroke management have markedly expanded the knowledge base for clinical decisions in carotid stenosis. Nevertheless, there is variability in carotid-related stroke prevention and management strategies across medical specialities. Optimal patient care can be achieved by (i) establishing a unified knowledge foundation and (ii) fostering multi-specialty collaborative guidelines. The emergent Neuro-Vascular Team concept, mirroring the multi-disciplinary Heart Team, embraces diverse specializations, tailors personalized, stratified medicine approaches to individual patient needs, and integrates innovative imaging and risk-assessment biomarkers. Proposed approach integrates collaboration of multiple specialists central to carotid artery stenosis management such as neurology, stroke medicine, cardiology, angiology, ophthalmology, vascular surgery, endovascular interventions, neuroradiology, and neurosurgery. Moreover, patient education regarding current treatment options, their risks and advantages, is pivotal, promoting patient's active role in clinical care decisions. This enables optimization of interventions ranging from lifestyle modification, carotid revascularization by stenting or endarterectomy, as well as pharmacological management including statins, novel lipid-lowering and antithrombotic strategies, and targeting inflammation and vascular dysfunction. This consensus document provides a harmonized multi-specialty approach to multi-morbidity prevention in carotid stenosis patients, based on comprehensive knowledge review, pinpointing research gaps in an evidence-based medicine approach. It aims to be a foundational tool for inter-disciplinary collaboration and prioritized patient-centric decision-making.

Best Medical Therapy for Asymptomatic Carotid Stenosis: Imminent or Ineffective?

Carotid artery disease accounts for approximately 20% of all ischemic strokes, a major cause of morbidity, and the fifth leading cause of death in the United States. Landmark trials in the 1990s, such as Asymptomatic Carotid Atherosclerosis Study and Asymptomatic Carotid Surgery Trial, establish carotid endarterectomy (CEA) plus best medical therapy (BMT) as the standard of care for patients with asymptomatic carotid stenosis over 60%. However, advances in medical therapy and the emergence of carotid artery stenting (CAS) have prompted a reevaluation of treatment efficacy. Recent studies have questioned the superiority of CEA over BMT alone in reducing stroke risk, suggesting no significant difference in outcomes with contemporary medical management. In addition, analysis from the U. S. Department of Veterans Affairs indicated minimal net benefit of CEA over BMT when accounting for all-cause mortality. Comparative studies have found no significant difference in long-term stroke-free survival between CEA and CAS. However, procedural risks vary, with higher myocardial infarction rates associated with CEA and higher stroke rates with CAS. Identifying high-risk plaques and patient-specific risk factors remains crucial. Meta-analyses have highlighted features such as neovascularization and lipid rich cores as predictors of stenosis progression and ischemic events. Ongoing research, particularly the CREST-2 trial, aims to provide clear guidance on the optimal treatment of asymptomatic carotid stenosis. This trial emphasizes stringent adherence to modern BMT protocols and includes comprehensive lifestyle modification programs. The evolving landscape of medical and surgical interventions necessitates continuous evaluation to optimize treatment strategies for asymptomatic carotid stenosis, which is the impetus for this review. Future findings from ongoing trials are expected to refine current guidelines and improve patient outcomes.

[Open surgical treatment for carotid stenoses]

BACKGROUND

Globally, stroke is considered the second most common cause of death. According to the German Federal Statistical Office, 33.6% of mortality was due to cardiovascular diseases, making them the most prevalent cause of death.

PROBLEM

Specifically, cerebral infarctions were recorded as the cause in over 16,000 cases. These figures underscore the significant role that cerebrovascular diseases play in Germany's mortality statistics. Notably, about 80% of strokes are ischemic. Moreover, one-fifth of all strokes result from extracranial carotid stenosis. The increase in stroke risk with advancing age, especially among men, is particularly striking. This trend highlights the growing importance of efficient stroke prevention and treatment in an aging society.

CONCLUSION

Open surgical therapy, as a crucial treatment method, is increasingly important, especially as an emergency intervention. Its role in modern medicine emphasizes the urgency of prioritizing this life-saving procedure in healthcare and making it widely available.

Natural history of internal carotid artery stenosis progression

OBJECTIVE

The aim of this study was to investigate the natural history of internal carotid artery (ICA) stenosis progression.

METHODS

This single-institution retrospective cohort study analyzed patients diagnosed with ICA stenosis of 50% or greater on duplex ultrasound from 2015 to 2022. Subjects were drawn from our institutional Intersocietal Accreditation Commission-accredited noninterventional vascular laboratory database. Primary outcomes were incidences of disease progression, and stroke or revascularization after index study. Progression was defined as an increase in stenosis classification category. Imaging, demographic, and clinical data was obtained from our institutional electronic medical record via a database mining query. Cases were analyzed at the patient and artery levels, with severity corresponding to the greatest degree of ICA stenosis on index and follow-up studies.

RESULTS

Of 577 arteries in 467 patients, mean cohort age was 73.5 ± 8.9 years at the time of the index study, and 45.0% (n = 210) were female. Patients were followed with duplex ultrasound for a mean of 42.2 ± 22.7 months. Of 577 arteries, 65.5% (n = 378) at the index imaging study had moderate (50%-69%) stenosis, 23.7% (n = 137) had severe (70%-99%) stenosis, and 10.7% (n = 62) were occluded. These three groups had significant differences in age, hypertension, hyperlipidemia prevalence, and proportion on best medical therapy. Of the 467-patient cohort, 56.5% (n = 264) were on best medical therapy, defined as smoking cessation, treatment with an antiplatelet agent, statin, and antihypertensive and glycemic agents as indicated. Mean time to progression for affected arteries was 28.0 ± 20.5 months. Of those arteries with nonocclusive disease at diagnosis, 21.3% (n = 123) progressed in their level of stenosis. Older age, diabetes, and a history of vasculitis were associated with stenosis progression, whereas antiplatelet agent use trended towards decreased progression rates. Of the 467 patients, 5.6% (n = 26) developed symptoms; of those, 38.5% (n = 10) had ischemic strokes, 26.9% (n = 7) had hemispheric transient ischemic attacks, 11.5% (n = 3) had amaurosis fugax, and 23.1% (n = 6) had other symptoms. A history of head and neck cancer was positively associated with symptom development. Of 577 affected arteries, 16.6% (n = 96) underwent intervention; 81% (n = 78) of interventions were for asymptomatic disease and 19% (n = 18) were for symptomatic disease. No patient-level factors were associated with risk of intervention.

CONCLUSIONS

A significant number of carotid stenosis patients experience progression of disease. Physicians should consider long-term surveillance on all patients with carotid disease, with increased attention paid to those with risk factors for progression, particularly those with diabetes and a history of vasculitis.

High Stroke Rate in Patients With Medically Managed Asymptomatic Carotid Stenosis at an Academic Center in the Southeastern United States

BACKGROUND

Although the publication of randomized clinical trials defining the benefit of carotid endarterectomy (CEA) for asymptomatic carotid stenosis, medical management of carotid stenosis has changed significantly. With antiplatelet agents and statins, some question whether these trials are still relevant, suggesting that asymptomatic patients with >70% internal carotid artery (ICA) stenosis may do better with medial management alone, lessening the need for CEA and carotid stenting. The Vascular Quality Initiative (VQI) registry has shown that there are wide practice variations regarding the degree of stenosis that prompts surgical intervention but there are few reports of outcomes in patients who do not undergo intervention. We sought to determine the clinical outcomes of the >70% carotid stenosis patients who are treated with medical management alone at our institution.

METHODS

We identified all patients with ICA stenosis >70% based on hemodynamic consensus criteria (peak systolic velocity >230 cm/s) in our peripheral vascular laboratory from January 2013 through December 2016. With a retrospective chart review, demographics, comorbid conditions, medications, radiographic studies, clinical follow-up, interventions, and outcomes at 2 years were included. Descriptive statistics were used to define these variables.

RESULTS

One hundred and seventy three patients were identified with medically managed asymptomatic >70% ICA stenosis based on hemodynamic criteria on duplex ultrasound. The mean age was 67.5 years, 49% were male, 64% were White, 14% were Black, 13% race was undisclosed, 89% were prescribed antiplatelet therapy, 85% were prescribed a statin, and 60% had hypertension controlled to <140/90. Twenty patients (11.5%) experienced a cerebrovascular event during the 2-year study period. There were eight patients with transient ischemic attack, 10 with ipsilateral strokes, and 2 with strokes in unrelated territories.

CONCLUSIONS

Despite good adherence to current recommendations for medical therapy, patients at our institution are developing symptomatic carotid disease at a rate similar to that reported in historical clinical trials. These data supports the concept that advances in medical management have not resulted in reduced stroke rates in asymptomatic patients with high-grade carotid stenosis at a large academic institution located in the southeastern United States. CEA and stenting provide a significant risk reduction and should be considered more often in this patient population.

Carotid atherosclerotic disease: A systematic review of pathogenesis and management

Carotid stenosis is an important contributor to ischemic stroke risk with resultant significant impact on neurological disability and death in adults and with worldwide implications. Management of carotid stenosis is impacted by whether there are associated symptoms along with the degree of stenosis. Understanding of the pathogenesis of carotid atherosclerosis or stenosis is important in management of carotid stenosis. Atherosclerotic plaque formation is a chronic insidious process with a number of potential contributors to the formation of such a plaque. The definition of atherosclerosis is not simply limited to abnormal deposition of lipid but also includes a chronic, complex, inflammatory process. Molecularly, in atherosclerosis, there is decreasing nitric oxide (NO) bioavailability, activity and/or expression of endothelial NO synthase, or increasing degradation of NO secondary to enhanced superoxide production. These above changes cause endothelial dysfunction leading to formation of foam cell followed by formation on lipid plaque. After lipid plaque formation, stable or unstable atherosclerotic plaque is formed depending on the calcium deposition over the lipid plaque. It continues to be clearly established that carotid intervention for symptomatic high-grade carotid stenosis is best managed with intervention either by carotid endarterectomy or carotid stenting. However, asymptomatic carotid stenosis is the subject of considerable controversy in terms of optimal management. This review of carotid atherosclerosis is an attempt to incorporate the information provided by more recent studies on pathogenesis and management which may help in the decision-making process for optimal management for protection against stroke.

Epidemiology of atherosclerotic carotid artery disease

Atherosclerotic carotid artery disease is a significant cause of stroke in the United States and globally. Its prevalence increases with age and it is more prevalent in men and White and Native-American populations. However, the outcomes related to carotid disease are worse in women and Black patients. Research suggests the disparities exist due to a multitude of factors, including disease pathophysiology, access to care, provider bias, and socioeconomic status. The prevalence of carotid stenosis in the general population is low (3%), and routine screening for carotid stenosis is not recommended in adults. Randomized clinical trials have shown benefits of stroke risk reduction with surgery (carotid endarterectomy or stenting) for symptomatic patients. Management is controversial in asymptomatic patients, as modern medical management has results equivalent to those of surgery and ongoing randomized clinical trials will address this important question. Carotid surgery is not appropriate in asymptomatic patients with limited life expectancy. Future work should explore comprehensive care models for care of patients with carotid disease and assessment of patient-reported outcomes to measure quality of care.