COMMON CAROTID-ARTERY OCCLUSION WITH PATENT INTERNAL AND EXTERNAL CAROTID ARTERIES - DIAGNOSIS AND SURGICAL-MANAGEMENT

Purpose: Occlusion of the common carotid artery (CCA) is generally associated with occlusion of the ipsilateral internal carotid artery (ICA) and external carotid artery (ECA). Occasionally, however, collateral circulation to the ECA may preserve patency of the ICA via retrograde perfusion through the bulb. These patients may suffer ongoing transient ischemic attacks and risk for stroke. Recognition of this pathologic variant may allow for effective surgical intervention. Methods: We have performed seven operations in six patients with occluded CCAs and patent ECA and ICAs. The occluded CCA was on the left side in each case (p < 0.01). Six of the operations were performed for ischemic symptoms, including amaurosis fugax in five patients, hemispheric TIA in one patient, and profound global ischemia in two patients who had concomitant occlusions of other extracranial vessels. In the five most recent cases the patent ECA and ICA above the occluded CCA were recognized by preoperative duplex scanning, which prompted cerebral angiography. A variety of reconstructive procedures were used, depending on the pathologic anatomy. These procedures included subclavian or axillary artery to carotid artery bypass with carotid endarterectomy (five), carotid endarterectomy with thrombectomy of the proximal CCA (one), and ascending aorta to carotid artery bypass (one). Results: There were no strokes associated with the surgery, although one patient had transient neurologic symptoms and a seizure associated with documented reperfusion edema. Three of the patients had preoperative and postoperative transcranial Doppler studies that documented significant improvement in intracranial hemodynamics. Five of the patients have had continuously patent grafts with relief of symptoms for an average of 40 months (range 3 to 155 months). The remaining patient had graft occlusion after 72 months and underwent repeat operation for amaurosis fugax and global ischemia. His second graft remains patent, and he is symptom free 21 months later. Conclusions: Recognition of patent distal vessels above a CCA occlusion depends on a high index of suspicion, careful investigation of the carotid bulb with duplex scanning, and delayed arteriographic views of the bulb allowing for late collateral vessel filling. The favorable results in this small series of patients supports an aggressive surgical approach when patients with symptoms are encountered with patent distal vessels above an occluded CCA.