Interventional therapy has also advanced, particularly in terms of perioperative management and device design. Because the absolute reduction in stroke risk with CEA in patients with an asymptomatic stenosis is small, however, the benefit of revascularization may be reduced or eliminated with current medical therapy.541 The benefit of CEA for carotid stenosis in asymptomatic women remains controversial.545 Given the reported 30-day, 1-year, and 3-year results in the high-surgical-risk population, it remains uncertain whether this group of asymptomatic patients should have any revascu- larization procedure. More data are needed to compare long- term outcomes after CEA and CAS. Currently, the Centers for Medicare & Medicaid Services cover CAS for asymptomatic stenosis only in patients with >80% stenosis at high risk for CEA who are participating in postmarket approval studies. For patients with asymptomatic carotid stenosis who defer revascularization, periodic reassessment of degree of stenosis may be helpful in identifying patients at higher risk of stroke. A retrospective ultrasound-based study of the deferred surgery arm of the ACST trial found that patients who had carotid ste- nosis that worsened in 1 year by 1 stenosis category did not have an increased risk of ipsilateral ischemic events, with cat- Patients who had a progression of 2 categories in 1 year were at high risk of ipsilateral ischemic events relative to nonprogressors. The recommendations below reflect current best evidence. However, modern optimal medical therapy may obviate the need for carotid revascularization. The balance of risks and benefits of revascularization in the setting of modern optimal medical therapy is being assessed in ongoing multicenter clin- ical trials in the United States and elsewhere. Asymptomatic Carotid Stenosis: Recommendations 1. Patients with asymptomatic carotid stenosis should be prescribed daily aspirin and a statin. 