A review of the immediate and long-term results of prophylactic carotid endarterectomy for asymptomatic lesions of 78 carotid arteries in 72 patients between 1961 and 1976 is presented. 2. The inhospital operative mortality was zero. Two patients experienced postoperative transient neurologic deficit with complete recovery (2.6 per cent). There were no postoperative strokes. 3. Late follow-up data demonstrated that in only one patient did a stroke subsequently develop appropriate to the operative side, and it occurred 4 years after operation. Life table analysis for neurologic events carried out for up to 15 years indicated a 96 per cent stroke-free status of the surviving patients. 4. A 42 month survival rate of 83 per cent in patients treated by prophylactic carotid endarterectomy represented a statistically significant improvement over the 67 per cent survival of a comparable group of patients reported on in the literature. 5. Prophylactic carotid endarterectomy in the experience of vascular surgeons who can offer a low operative morbidity and mortality appears to be reasonable therapy in preventing stroke and prolonging survival until a randomized controlled study comparing surgery with the natural history of untreated patients shows evidence to the contrary.
