"Stump" on internal carotid artery--a source for further cerebral embolic ischemia.

A series of 9 patients have experienced hemisphere and retinal ischemia at an interval after occlusion of appropriate internal carotid arteries. All had radiological evidence of a persisting proximal stump to the occluded artery and, in most, pathological evidence of thrombotic material attached to atheromatous lesions within the stump. Thromboembolism from the stump via the anastomotic supply through ipsilateral common and external carotid arteries is thought to be responsible for the ischemic events to the brain or retina despite absence of flow through the internal carotid artery. Seven of the 9 were treated by surgical excision or obliteration of the stump and, when indicated, common and external carotid endarterectomy. Turbulence in the stump contributed to progressive atherosclerotic changes and probably aggravated thrombogenesis in this location with subsequent embolization into the anastomotic arteries.