Mobile thrombus developing in a stent at a left ICA stenotic lesion demonstrated by carotid color flow ultrasonography after implantation with a second stent to treat left vertebral stenosis: case report

Abstract

A 60-year-old Japanese man who had undergone stent treatment for stenosis of the left carotid artery received another stent 5 months later to treat a stenotic region of the left vertebral arterial origin. Color flow ultrasonography of the carotid artery before the second stenting procedure revealed good blood flow without any defects in the previous stent. However, the day after implantation of the vertebral arterial stent, carotid color flow ultrasonography identified a new low-echoic mobile structure at the left carotid stent. This structure was diagnosed as thrombus after showing a marked decrease in size after starting anticoagulant therapy. We speculate that the coagulation system, promoted by stent implantation at the vertebral arterial origin, contributed to thrombus formation in the stent at the left carotid artery. Carotid color flow ultrasonography was helpful for detecting low-echoic mobile thrombus in a carotid stent in the present case, and may prove useful for similar future cases.