Staged Endovascular Treatment for Symptomatic Occlusion Originating From the Intracranial Vertebral Arteries in the Early Non-acute Stage

Abstract

Background: The ideal treatment for patients who survive from acute vertebrobasilar artery occlusion but develop aggressive ischemic events despite maximal medical therapy in the early non-acute stage is unknown. This paper reports the technical feasibility and outcome of staged endovascular treatment in a series of such patients with symptomatic intracranial vertebral artery occlusion. Methods: Ten consecutive patients who presented with aggressive ischemic events in the early non-acute stage of intracranial vertebral artery occlusion from Jan 2015 to Nov 2020 were retrospectively reviewed. Among them, eight male and two female patients with a mean age of 66.7 years developed aggressive ischemic events, and the NIHSS score was elevated by a median of 7 points despite medical therapy. All patients received staged endovascular treatment 4-21 days from onset, at an average of 11 days. The strategy of staged treatment was as follows: first, a microwire was passed through the portion of the occlusion, which was then dilated with balloon inflation to maintain the perfusion above TICI grade 2b. Then, with the use of antiplatelet drugs, the residual intravascular thrombus was gradually eliminated by the continuous perfusion and an activated fibrinolytic system, leaving the residual stenosis. A second stage of angioplasty with stent implantation was subsequently performed if residual stenosis was ≥50%. The NIHSS scores and mRS scores were compared between pre- and post-endovascular treatment groups and in the follow-up period. Results: Technical success was achieved in 9 patients who received staged endovascular treatment (perforation occurred in one patient during the first stage). The NIHSS scores were significantly improved, with a median score 7 points lower on discharge compared with the scores for the most severe status. Favorable outcomes with mRS score ≤ 2 were achieved in 7 and 9 patients at the 3-month follow-up and the latest follow-up, respectively, which was better than the preoperative status. Conclusion: Staged endovascular treatment might be a safe, efficient, and viable option in carefully selected patients with symptomatic intracranial vertebral artery occlusion in the early non-acute stage. However, this needs to be confirmed by further investigation, preferably in a large, controlled setting.

Keywords: endovascular treatment; occlusion; recanalization; staged; vertebral artery.

Figure 1

Imaging studies of case 1. Axial FLAIR MRI sequences showed ischemic infarctions in the pons (A) and bilateral cerebellum (not shown here). The right vertebral artery was hypoplastic (B), and the left vertebral artery was occluded from the V3 segment onward (C). The right PCOM supplied the PCA with retrograde flow to the top of the BA (D). In the first stage of endovascular treatment, the left intracranial vertebral artery was recanalized by passing a microwire through and dilating a balloon in the stenotic region; some thrombus material remained on the vessel wall (white arrow) (E). In the second stage of endovascular treatment, vertebral angiography showed that the thrombus had disappeared, leaving only the primary stenosis (F), which was fully resolved by angioplasty with stenting (G). Follow-up MRA performed 6 months later showed that the perfusion of the left intracranial vertebral artery and BA was unobstructed (H). MRI, magnetic resonance imaging; FLAIR, fluid-attenuated inversion recovery; PCOM, posterior communicating artery; PCA, posterior cerebral artery; BA, basilar artery; MRA, magnetic resonance angiography.

Figure 2

Imaging studies of case 3. CTA in a local hospital showed severe stenosis of the right intracranial vertebral artery 6 months before admission (A). Axial T2-weighted MRI showed ischemic infarction in the right cerebellum (B). The left intracranial vertebral artery was occluded, and the BA was supplied by the anastomotic branches and leptomeningeal collaterals (C). The right intracranial vertebral artery was occluded from the V3 segment onward (D). In the first stage of endovascular treatment, the right intracranial vertebral artery was recanalized by balloon inflation (E), and stable perfusion was achieved after sufficient dilation with 3 balloons; however, some thrombus remained on the vessel wall (F). CTA performed 1 week later showed intraluminal thrombus and a dissection in the right intracranial vertebral artery (G). Two weeks later, CTA showed that the thrombus had decreased significantly, leaving a dissection and residual stenosis (H). Angiography performed in the second stage confirmed that the thrombus had disappeared and that there was a dissection (white arrow) and residual stenosis in the V4 segment of the intracranial vertebral artery (I); the dissection and stenosis were resolved by a Winspan stent (J). Follow-up angiography performed 12 months later showed moderate stenosis in the proximal part of the stent (K). CTA, computed tomography angiography; MRI, magnetic resonance imaging; BA, basilar artery.