Symposium on Cerebrovascular DiseasesEvaluation and Management of Asymptomatic Carotid Artery Stenosis
Section snippets
NATURAL HISTORY
Clearly, the baseline risk of stroke in patients with asymptomatic ICAS is one of the most important factors to consider when interpreting the relative reduction and absolute reduction in stroke risk for any intervention. It is especially important when helping patients decide whether to undergo CEA for asymptomatic ICAS. Most short-term (2-3 years) natural history studies of asymptomatic ICAS have reported an annual risk of unheralded ipsilateral stroke of approximately 1% to 3%, depending on
EVIDENCE FOR CEA FOR ASYMPTOMATIC ICAS
Carotid endarterectomy was evaluated in 6 prospective, randomized, controlled clinical trials.4, 5, 6, 7, 24, 27 One study involved 57 asymptomatic patients with cervical bruits and abnormal findings on ocular pneumoplethysmography, 29 of whom were randomized to aspirin or CEA.27 More unfavorable outcomes were noted in those patients who underwent CEA, and the investigators concluded that most asymptomatic patients with cervical bruits and abnormal findings on ocular pneumoplethysmography are
SCREENING AND MONITORING FOR ASYMPTOMATIC ICAS
Publication of the ACAS in 1995 was followed by a large increase in the number of CEAs performed in the United States.42 Since then, guidelines and position papers have recommended clinical implementation of this prophylactic surgery.14,43, 44, 45, 46 The patients discussed are, by definition, neurologically asymptomatic; therefore, patients can be identified only through some form of case-finding or screening strategy. When screening tests are applied to large unselected populations, the
EVALUATION OF ICAS
Digital subtraction angiography (DSA) was used to assess the degree of stenosis in the early endarterectomy trials and thus became the gold standard for selecting patients for CEA. In the most recent ACST, sonographic assessment was used. When compared with MRA and CTA, DSA has a comparatively small risk of morbidity: the risk of permanent neurologic deficit ranges from 0.7% to 1.2%.7, 65 Even patients with no apparent neurologic complications after DSA have developed minor asymptomatic
IMPLICATIONS FOR CLINICIANS
According to the evidence, CEA in asymptomatic patients with moderate to severe ICAS reduces the odds of stroke by about 30% over a 3-year period. However, although this relative risk reduction appears impressive, the absolute benefit is extremely small because the risk of stroke without surgery for asymptomatic stenosis is low. In addition, the clinician and patient must consider the fact that the risk of treatment (surgical stroke) is present for several weeks, whereas the benefit accrues
CONCLUSIONS
Internal carotid artery stenosis of greater than 50% is present in approximately 4% to 8% of the population aged 50 to 79 years. Natural history studies and clinical trials reveal a small increase in stroke risk in patients with increasing degrees of stenosis, especially in those with greater than 80% diameter reduction. Paradoxically, this correlation between stroke risk and degree of stenosis has not been demonstrated in the asymptomatic CEA trials. The evidence does not appear to support the
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Carotid, Vertebral, and Brachiocephalic Interventions
2020, Interventional Cardiology ClinicsCitation Excerpt :Most ischemic strokes in patients with asymptomatic carotid stenosis are preceded by TIAs.17–19 As a result, some experts recommend watchful waiting of patients with asymptomatic carotid stenosis until they experience a TIA.20,21 However, the risk of stroke without warning was about 1% to 2%, suggesting that watchful waiting may not be an optimal strategy and early intervention may be beneficial instead.22–24
Multidetector-Row Computed Tomography in Evaluation of Atherosclerotic Carotid Plaques Complicated with Intraplaque Hemorrhage
2009, Annals of Vascular SurgeryCitation Excerpt :Asymptomatic patients with carotid artery stenosis comprise 11-52% and 37-92% of all patients operated for carotid artery stenosis in Europe and the United States, respectively.30-43 Several authors have indicated that operative treatment of asymptomatic patients with carotid artery stenosis should be considered only for medically stable patients with ≥80% stenosis with life expectancy of at least 5 years and only if a <3% perioperative complication rate can be achieved.44,45 Asymptomatic patients with complicated plaque and <80% carotid artery stenosis, who would not be treated if the above-mentioned recommendations are applied, could benefit from a diagnostic method that is able to detect some features of carotid plaque associated with increased risk of a cerebrovascular event.
OCT in cardiovascular medicine
2006, Optical Coherence Tomography: Principles and ApplicationsCarotid artery stenosis An approach to its diagnosis and management
2021, Australian Journal of General PracticeShort term outcomes of endarterectomy to asymptomatic extracranial carotid artery disease
2020, Duzce Medical JournalState of the art
2019, Klinikarzt
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