Elena Zapata-Arriaza, MD
Basilar artery (BA) is more frequently associated to positive remodeling; however, the opposite may also occur. Negative remodeling due to intracranial atherosclerotic disease involves a narrowing in the vessel lumen and is related to higher stroke risk. However, the information about remodeling pattern and its influence in stroke risk after angioplasty and stenting is scarce.
To answer the question, the authors studied patients with symptomatic intracranial arterial stenosis who were assessed with high-resolution magnetic resonance imaging (HRMRI) from September 2014 to January 2017. Among them, patients with BA stenosis who underwent angioplasty and stenting were recruited. Arterial remodeling patterns were divided into negative or nonnegative (positive and intermediate remodeling) remodeling according to remodeling index. (Remodeling index ≥1.05 was defined as positive remodeling, 0.95 and 1.05 as intermediate remodeling, and ≤0.95 as negative remodeling.) Plaque features were investigated by HRMRI. Incidence of perforator strokes after intracranial stenting was collected. Plaque features and incidence of post stenting perforator stroke were compared between negative and nonnegative remodeling.
Among 298 patients enrolled, thirty patients fulfilled the inclusion criteria. There were 36.7% of patients with negative remodeling and 63.3% of patients with nonnegative remodeling. Twenty-six patients (86.7%) had diffuse distribution, 5 patients (16.7%) had intraplaque hemorrhage, 2 patients (6.7%) had calcification, and 17 patients (65.4%) had enhancement. Three patients (10%) had perforator stroke after stenting. Plaque features were similar between negative and nonnegative remodeling groups. Patients with negative remodeling were more likely to have perforator stroke after stenting comparing with patients with nonnegative remodeling (27.3% versus 0%, P=0.041).
As the results obtained in the present study suggest, perforator stroke after BA stenting is more likely to be associated with negative remodeling. Angioplasty and stenting in BA stenosis treatment is mostly based on angiography characteristics of lumen narrowing, rather than remodeling patterns.
Angioplasty device choice without taking into account the remodeling pattern involves an incomplete planning of the procedure. However, the angioplasty balloons perform dilation in a uniform manner and cannot prevent the displacement of atheromatous plaque towards the BA perforators ostium. The results of this study indicate a possible cause of stroke in BA perforators after stenting; however, we still lack the adequate devices to avoid it.