Clinical Outcome of Patients Developing Transient Ischemic Attacks Following Carotid Endarterectomy

Abstract

Little is known about the clinical outcome of patients who develop ipsilateral transient ischemic attacks (TIAs) or amaurosis fugax (AF) following carotid endarterectomy (CEA). This review was undertaken to define the natural history of this group of patients and to formulate a rational approach for the evaluation and treatment of their symptoms. From April 1976 to December 1996, 1,121 CEAs were performed at the authors' institution. They reviewed the short- and long-term outcomes of 33 patients (34 CEAs) who developed ipsilateral AF or TIAs as their initial postoperative neurologic event following surgery. Mean follow-up after CEA was 77.0 ± 57.4 months (range 3-220 months), and 49.9 ±52.2 months after occurrence of the initial episode of TIA or AF. Eleven patients suffered from an early initial ipsilateral TIA or AF within 30 days of CEA, and 23 patients developed late initial ipsilateral TIA or AF during later follow-up. Five secondary neurologic events (15%) occurred after initial ipsilateral TIA or AF. Two patients suffered ipsilateral strokes (one fatal and one nonfatal), one patient developed a recurrent ipsilateral TIA, another a contralateral stroke, and a fifth patient suffered nonhemispheric symptoms following postoperative ipsilateral AF or TIAs. Following the occurrence of initial ipsilateral TIA or AF, 1-, 2-, and 3-year ipsilateral stroke-free rates were 96%, 96%, and 89%, respectively. Recurrent carotid stenosis (>50% diameter reduction) as determined by color flow duplex scanning was present in 10 of 34 (29%) arteries at the time of the initial ipsilateral TIA or AF but correlated poorly with the development of secondary neurologic symptoms. Secondary CEA was performed on six arteries, two for ulcerated carotid lesions < 50%, two for recurrent lesions with 50-79%, and two for recurrent lesions with 80-99% stenosis. All six patients remained free of symptoms following their secondary operation. These results suggest that the majority of patients who suffer initial ipsilateral TIAs or AF following CEA enjoy a favorable neurologic prognosis, are not associated with recurrent carotid stenosis, and enjoy a natural history similar to patients who develop TIA or AF with normal or minimal to mild internal carotid artery disease. The authors conclude that most patients with postoperative AF or TIA can be managed safely with medical therapy and routine clinical follow-up and that few require surgical treatment.