Résumé : The authors report a case of infected false aneurysm that developed after carotid endarterectomy with vein patch angioplasty. This complication is extremely rare and occurs most commonly when a Dacron patch graft has been employed. Various clinical presentations are described and the etiology of infection is discussed. Surgical management consisted of the resection of the pseudoaneurysm and segmental replacement with vein. Parenteral antibiotic therapy was given for three weeks and topical irrigation with an antiseptic solution performed for two weeks.