A case of recurrent aneurysm resulting from dual antiplatelet plus anticoagulation after confirmed aneurysm closure following coil-assisted flow diversion

Abstract

Dual antiplatelet therapy (DAPT) is a management cornerstone for intracranial aneurysms treated with flow diversion. However, combined dual antiplatelet plus anticoagulation (triple therapy) can be indicated in some patients with important associated risks. Here we present the case of a 72-year-old woman with prior history of subarachnoid hemorrhage who was started on triple therapy (enoxaparin and DAPT) following successful flow diversion of an enlarging but unruptured left fetal posterior communicating artery aneurysm. Her post-procedural course was complicated by in-stent thrombosis in the setting of a missed ticagrelor dose and subsequent development of deep venous thrombosis and pulmonary embolism. An early follow-up angiogram confirmed occlusion of the aneurysm. However, after initiation of triple therapy, the aneurysm partially recanalized and her symptoms recurred. Subsequent discontinuation of enoxaparin lead to prompt aneurysm re-occlusion. To our knowledge, this is the first reported instance of confirmed intra-aneurysmal thrombolysis in a successfully treated aneurysm after triple therapy initiation.

Keywords: Aneurysm recurrence; Anticoagulation; Flow diversion; Triple therapy.

Fig. 1

(A) Digital subtraction angiography (DSA) demonstrating a lobulated left lobulated posterior communicating artery aneurysm (white arrow). (B) Subsequent coiling and placement of flow diversion stents with landing zones past the base of the aneurysm (black) arrows. Surgical clip from prior contralateral aneurysm clipping (white arrow). (C) Reduced opacification of the aneurysm dome immediately after flow diversion with adjunct coiling.

Fig. 2

(A) MR imaging after thrombectomy for in-stent occlusion demonstrating no opacification of the excluded left posterior communicating artery aneurysm (white arrow). (B) Interval MR imaging 4 months post treatment demonstrating interval partial re-opacification of the aneurysm while patient was on enoxaparin in addition to DAPT (white arrow). (C) DSA 6 months post treatment and 2 months after discontinuation of enoxaparin demonstrating interval re-thrombosis with continued opacification of the aneurysm base (white arrow).