Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery

Abstract

Purpose: The study aimed to investigate the safety, effect, and risk factors of endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery (SNOVA).

Materials and methods: Patients with SNOVA were retrospectively enrolled and treated with endovascular recanalization. The clinical data, endovascular treatment, peri-procedural complications, and follow-up outcomes were analyzed.

Results: A total of 88 patients were enrolled, with an interval to recanalization of 2-89 days (median 23) and an mRS of 2-5 (median 3 and IQR 1). Occlusion was in the intracranial vertebral artery in 68 (77.27%) patients and basilar artery in 20 (22.73%), with an occlusion length of 4.5-43.7 mm (mean 18.3 ± 8.8). Endovascular recanalization was successful in 81 (92.0%) patients. Post-dilatation was performed in 23 (28.4%) patients. After stenting, the residual stenosis was 10%-40% (mean 20.2% ± 7.6%). Peri-procedural complications occurred in 17 (19.3%) patients, with a mortality rate of 5.7%. In total, 79 (95.18%) patients underwent follow-up 5-29 (mean 16.9 ± 5.5) months later, with an mRS score of 0-6 (median 1 and IQR 1) at follow-up, being significantly (p < 0.0001) better than that at discharge. Stroke occurred in 9 patients (11.4%) in 1 year. In-stent restenosis occurred in 19 (25.33%) patients. Significant (p < 0.05) independent risk factors were blunt occlusion for successful recanalization, duration to recanalization and blunt occlusion for peri-procedural complications, and post-dilatation for both in-stent restenosis and 1-year stroke or death events.

Conclusion: Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery is feasible even for a long occlusion segment, with a high recanalization rate, a low complication rate, and a good prognosis. Blunt occlusion and duration from the onset to recanalization may affect successful recanalization and peri-procedural complications while post-dilatation may affect in-stent restenosis and prognosis.

Keywords: basilar artery; endovascular recanalization; intracranial vertebral artery; non-acute; symptomatic occlusion.

Figure 1

Flowchart of patient enrollment.

Figure 2

Occlusion angles and types of occlusion shape. (A) The arterial angle formed between the proximal and distal segments at the occlusion was measured. (B–D) Types of occlusion shape were defined, with the sharp occlusion in B1, B2 (arrow), blunt occlusion in C1, C2 (longer arrow), and flame-like occlusion in D1, D2 (arrow). The double arrows in C indicate the posterior inferior cerebellar artery. (B1, B2) The sharp occlusion shape in the major blood-supplying vertebral artery was shown in cerebral angiography in B1 and in the sketch in B2. (C1, C2) The blunt occlusion in the major blood-supplying vertebral artery was shown in cerebral angiography in C1 and in the sketch in C2. (D1, D2) The flame-like occlusion in the major blood-supplying vertebral artery was shown in cerebral angiography in D1 and in the sketch in D2.

Figure 3

Receiver operating characteristic (ROC) curve analysis of the duration from symptom onset to recanalization as a risk factor for peri-procedural complications.