Late Thromboembolic Events after Treatment of Intracranial Aneurysms with Guglielmi Detachable Coils
Purpose: Thrombo-embolic complications associated with the endovascular treatment of intracranial aneurysms with Guglielmi Detachable Coils (GDC) generally occur at the time of the procedure or soon after. The purpose of this report is to determine the frequency of late thrombo-embolic events after GDC. Methods: The records of 189 patients who underwent GDC repair of one or more intracranial aneurysms at our institution were reviewed. The occurence of an ischemic event referrable to a coiled aneurysm was determined by clinical, angiographic, and imaging data. Events occuring within 2 days of the endovascular procedure were considered peri-procedural. Kaplan-Meier analysis of ischemic events over time was performed. Results: Two patients suffered documented thrombo-embolic events. One patient presented 5 weeks after coiling with a transient ischemic attack. Angiography demonstrated thrombus on the surface of the coils at the neck of a large ophthalmic artery aneurysm. The second patient presented with a posterior circulation stroke 4 weeks after coiling of a large superior cerebellar artery aneurysm. Angiography showed no significant proximal disease, with thrombus beginning at the neck of the treated aneurysm and extending out both P1 segments. No intra-procedural problems during the initial coiling had occured with either patient. There was no evidence for protrusion of coils into the parent artery in either patient. Both patients had been receiving daily aspirin (325 mg). One additional patient reporting symptoms suggesting possible ischemics event was evaluated and diagnosed as having atypical migraines. The frequency of a clinical thromboembolic event during the first year after coiling (excluding procedural complications) was 1.1%. Conclusions: Thrombo-embolic events may occur as late as 5 weeks after endovascular treatment of aneurysms with GDC.