Improving Outcomes in Patients With Carotid Stenosis

See related article, p 91.Knowing how to best prevent stroke in patients with carotid artery stenosis is of major public health importance because carotid stenosis is common in older people and causes ≈10% of all strokes.1 For decades it has been thought that patients with carotid plaques showing a predominance of echolucent tissue by ultrasound imaging have higher stroke risk and are more likely to benefit from carotid procedures.2 The accompanying meta-analysis by Gupta et al3 is important because it demonstrates that predominantly echolucent asymptomatic carotid plaques carry ≈2.5× the risk of ipsilateral stroke over the next 2 years or so compared with predominantly echogenic plaques. The meta-analysis also shows that predominantly echolucent plaques are common, making up 23% of stenosing or nonstenosing plaques and 31% of plaques causing ≥50% stenosis.Understanding the clinical significance of these novel results, particularly with respect to the potential value of carotid procedures, requires knowledge of absolute stroke risks. Patients with 50% to 99% asymptomatic carotid stenosis (ACS) have been the focus because carotid endarterectomy (CEA) was shown to provide a small, overall stroke prevention advantage in patients randomized 20 to 30 years ago to CEA and medical treatment (encouragement of healthy lifestyle habits and appropriate medication) versus medical treatment alone.4,5 However, the most recent quality measurements of the average annual rate of ipsilateral stroke in patients with 50% to 99% ACS given medical treatment alone approximate 0.5% to 1.0%.6 Using a 2.5× higher relative risk of ipsilateral stroke for predominantly echolucent plaques gives an expected average annual rate of ipsilateral stroke of ≈1.5% to 2.5%. This is too low to expect an overall stroke …