Prevention of Ischemic Stroke: Surgery

Abstract

The last 15 years have witnessed a resurgence of the role of surgical options for prevention of ischemic stroke. The landmark randomized trials including NASCET and ECST were published and explored the role of carotid endarterectomy in this regard. Patients with high grade stenosis of the internal carotid artery (> or = 70%) with prior TIA or minor non disabling stroke in the same territory were shown to have significant benefit of the procedure compared to best medical treatment. Benefit was comparatively less in patients with moderate grade stenosis of the ICA (50-69%). Surgical treatment of patients with <50% stenosis of the ICA resulted in worse outcomes compared to medical therapy and is consequently not recommended. These studies also standardized the method for measuring the degree of ICA stenosis. The ACAS and ACST studies attempted to resolve the rather vexing issue of surgical treatment of patients with asymptomatic ICA stenosis. The risk benefit ratio in asymptomatic patients is low and depends to a large extent on a low perioperative complication rate. Studies have also attempted to identify the best medical treatment in the perioperative period during CEA. Low dose aspirin has been shown to be beneficial, but the role of statins and betablockers is promising but yet uncertain. Ischemic stroke is a common complication after CABG. In this regard surgeons have differed in their approaches to performing CEA, some preferring to do it during the bypass surgery, while others prefer a two staged procedure. The surgical treatment of complete carotid occlusion by EC-IC bypass surgery has also enjoyed renewed interest and results of the COSS study are awaited keenly. The EC-IC bypass surgical procedure is also beneficial in moya-moya disease.