Self-expanding stent for recanalization of acute embolic or dissecting intracranial artery occlusion

Abstract

Background and purpose: Stent placement may be an effective and last resort method for recanalization of recalcitrant intracranial artery occlusion. The purpose of this study was to evaluate the safety and efficacy of a self-expanding stent for the recanalization of acute embolic or dissecting intracranial artery occlusion.

Materials and methods: Nine patients (mean age, 66 years; NIHSS score, 10-23) with acute embolic (n = 8) or dissecting occlusion (n = 1) of the intracranial arteries (ICA terminus in 5, MCA in 3, and BA in 1) were treated with a recapturable self-expanding stent. The safety and efficacy of the stent for recanalization were evaluated retrospectively.

Results: The emboli were entrapped against the vessel wall by the stent, resulting in immediate recanalization (TIMI 2) in all embolic occlusions. The dissecting occlusion was recanalized completely (TIMI 3). Adjunctive thrombolytics (n = 8, urokinase, 100,000-300,000 U) and/or GP IIb/IIIa antagonist (n = 7, tirofiban, 0.5-1 mg) were administered intra-arterially, and the degree of recanalization further improved in 4 embolic occlusions (TIMI 3). Acute in-stent thrombosis occurred in 2 patients, who received only urokinase without GP IIb/IIIa antagonist. Both of the reoccluded arteries were reopened, by stent recapture in 1 and by intra-arterial administration of GP IIb/IIIa antagonist in the other. Recapture was attempted in 7 cases, of which there were 3 successful outcomes. There was 1 asymptomatic hemorrhagic conversion at the infarction site. The mean improvement of the NIHSS score between baseline and discharge was 12.3 (range, 3-22).

Conclusions: Preliminary results of this study suggest that a self-expanding stent may be safe and efficient for recanalization of acute embolic or dissecting intracranial artery occlusion.

Fig 1.

Case 1. A 44-year-old woman who presented with acute stroke and an NIHSS score of 22. A, Left internal carotid angiogram in the lateral projection shows acute cutoff just above the takeoff of the posterior communicating artery. B, Partial deployment of the Enterprise stent. Note the distal markers of the stent (white arrow) and the distal marker of the Prowler Select Plus microcatheter (black arrow). C, Three-hour delay angiogram in the lateral projection after the intra-arterial administration of urokinase (100,000 U), and tirofiban (0.5 mg), reveals a TIMI 3 recanalization. Note a notch (arrow) in the stent corresponding to the portion in which thrombus is entrapped between the stent and the arterial wall. D, Follow-up angiogram 1 week after thrombolysis reveals the full expansion of the previously noted notch in the stent and normal flow from the ICA to the MCA and ACA.

Fig 2.

Case 6. A 74-year-old woman presenting with a stuporous mental state. A, Right vertebral artery angiogram reveals embolic occlusion of the BA terminus. B, Immediately after the partial deployment of an Enterprise stent, a TIMI 2 recanalization is achieved. Note the distal markers of the partially deployed stent (arrow). C, On an angiogram 10 minutes after the adjunctive intra-arterial administration of urokinase (100,000 U), in-stent reocclusion occurs. D, Although thrombus removal is attempted by the recapture of the stent, persistent reocclusion is noted. E, TIMI 2 recanalization (arrow) immediately after the second partial deployment of the stent. F, Intra-arterial administration of the GP IIb/IIIa antagonist (tirofiban, 1 mg) improves the recanalization state, and the stent is retrieved (not shown). The final angiogram after recapture of the stent shows complete recanalization from the BA to the right PCA, but the occlusion of the left PCA still remains. G, Follow-up MR angiogram reveals complete recanalization from the BA to the bilateral PCAs.