Downward Migration of Carotid Stent on 8 Months Follow-Up Imaging: Possible Stent “Watermelon- Seeding” Effect

Abstract

One method used to treat atherosclerotic carotid disease is carotid artery stenting (CAS). A rarely encountered limitation of this technique is stent migration. Here, we present a rare case of carotid stent downward migration found on follow-up imaging 8 months post operation. A 70-year-old man presented with aphasia and right-sided weakness secondary to high-grade (99%) proximal left internal carotid artery (ICA) stenosis that was treated with CAS. Stent apposition distally was achieved as well as proximally at the carotid bulb without crossing the bifurcation and without going distally beyond the ICA angulation to avoid kinking. Eight months follow-up computerized axial angiogram showed downward migration of the stent into the common carotid with restenosis distal to the stent. A 6-8 × 40 mm stent was deployed and the stenosed area restented with good results to overlap with the older stent and landed distal to the ICA angulation. Interventionalists should be aware of the rare possibility of migrating downward "watermelon-seeding" of carotid stents. This report may generate the hypothesis that the stent watermelon-seeding effect may be related to proximal placement of a short stent below the ICA angulation and at the carotid bulb in severely stenotic lesion.