Patterns and implications of artery remodeling based on high-resolution vessel wall imaging in symptomatic severe basilar artery stenosis

Abstract

Background: Knowledge regarding the influence of arterial remodeling patterns on plaque characteristics and postoperative outcomes in patients with severe basilar artery (BA) stenosis after endovascular treatment is lacking. The purpose of this study was to investigate plaque characteristics, remodeling patterns, and perioperative outcomes in patients with severe BA stenosis.

Methods: A prospective cohort study was conducted on symptomatic patients with severe BA stenosis who underwent high-resolution MRI before endovascular treatment. The remodeling index, plaque burden, and area of stenosis were evaluated for each plaque. Based on the remodeling index calculated by high-resolution MRI, remodeling patterns were classified as negative remodeling (NR) or non-negative remodeling (non-NR). Baseline demographics, plaque features, and treatment characteristics were compared between the NR and non-NR groups. Correlations between the remodeling index, plaque burden, and stenosis severity were also examined.

Results: In total, 140 eligible patients were included and analyzed, including 91 non-NR cases and 49 NR cases. A strong correlation existed between the remodeling index and plaque burden (r=0.973, P<0.001), and a marginal correlation was observed between the remodeling index and degree of stenosis by area (r=-0.261, P=0.0019). There was no significant difference between the two groups in terms of perioperative complications related to ischemic events and new ischemic cerebral lesions (NICLs).

Conclusions: Under the current submaximal angioplasty and/or stenting treatment paradigms, remodeling patterns may not influence the outcome of ischemic events and NICLs. However, the remodeling index is strongly associated with plaque burden, which may provide insight for the evaluation of severe BA stenosis. Further research is warranted.

Keywords: Basilar stenosis; atherosclerosis; magnetic resonance imaging; stroke; vascular remodeling.

Figure 1

The schematic of plaque remodeling and plaque distribution. (A) Arterial remodeling patterns include negative remodeling (NR), intermediate remodeling (IR), and positive remodeling (PR) at the site of maximal luminal narrowing (MLN) compared with the reference site. (B) The anatomy of the basilar artery shows the segmentation referred to as the superior cerebellar artery and anterior inferior cerebellar artery. A junctional lesion was considered when the lesion crossed the anterior inferior cerebellar artery.

Figure 2

The graphs in the upper row show the relationships between the remodeling index, plaque burden, and area of the degree of stenosis. (A) The remodeling index was strongly associated with plaque burden, fitting an inverse equation between them (r=0.973, P<0.001). (B) The remodeling index was marginally associated with the area of the degree of stenosis (r=−0.261, P=0.0019). (C) The area of the degree of stenosis was not related to plaque burden (r=0.068, P=0.520). The images in the lower row demonstrate basilar artery remodeling patterns based on high-resolution magnetic resonance. Vessel area (VA) and lumen area (LA) at the site of maximal luminal narrowing (MLN) and reference (REF) site were manually traced for measuring. (D) An adult patient showed negative remodeling with a plaque burden of −41.9% and remodeling index of 0.50. (E) An adult patient showed intermediate remodeling with a plaque burden of 24.7% and remodeling index of 0.96. (F) An adult patient showed positive remodeling with a plaque burden of 32.5% and remodeling index of 1.10.