Asymptomatic endorectal coil migration following hemorrhoidal artery embolization: A case report

Hemorrhoidal artery embolization (HAE) is an increasingly utilized minimally invasive treatment for symptomatic internal hemorrhoids with a favorable safety profile. As adoption expands, rare delayed complications may emerge. We report a case of delayed asymptomatic endorectal coil migration identified 11 months following HAE. The procedure was performed via common femoral arterial access using selective microcatheterization of distal branches of the superior rectal artery. Embolization was achieved using 600-µm microspheres and multiple pushable microcoils deployed distally to the hemorrhoidal plexus. The patient experienced partial symptom recurrence requiring subsequent rubber band ligation (RBL). Surveillance colonoscopy later demonstrated partial extrusion of a metallic coil through the rectal mucosa without associated pain, bleeding, infection, or ischemia. The patient was managed conservatively with no intervention. Potential mechanisms for delayed coil migration include mucosal thinning following devascularization, chronic inflammatory remodeling, and mechanical factors related to subsequent anorectal interventions such as RBL; however, causality cannot be definitively established. This case highlights the importance of long-term follow-up and awareness of delayed device-related findings as HAE continues to evolve in clinical practice.