Non-stenotic intracranial plaques which can be frequent in embolic strokes of unspecified sources

Non-stenotic intracranial plaques likely play an etiological role in embolic stroke of an undetermined source (ESUS), according to a retrospective study published in the Journal of the American College of Cardiology.

This study retrospectively enrolled patients (N = 403) with small vessel disease (SVD; n = 160) or ESUS (n = 243) treated at the Northern Theater Command General Hospital in China between 2015 and 2019 for clinical assessment plaque based on magnetic resonance imaging (MRI) data contained in patient records.

The ipsilateral and contralateral plaque characteristics did not differ significantly in patients with SVD. In patients with ESUS, the ipsilateral and contralateral plaques differed in terms of load (63.8% versus 60.4%; P = 0.002), remodeling index (1.166 versus 1.091; P <0.001), and discontinuity of the plaque surface (73.5% versus 59 , 6%); P = 0.018) or complicated plaque (76.8% versus 59.6%; P = 0.003).

25.9% of the patients with ESUS had only ipsilateral plaques, 4.9% only contralateral plaques and 37.9% bilateral plaques. Patients with ESUS had an increased risk of presenting with plaques (odds ratio) [OR]5.25; 95% CI, 2.83-9.73) and more non-stenotic intracranial plaques were observed in patients with ESUS (68.7%) compared to patients with SVD (40.0%; P <0.001).

In a multivariate regression analysis it was found that an increased remodeling index (per 0.1 increase) is the only significant predictor for ESUS (odds ratio) [OR]2,295; 95% CI, 1.661-3.172; P <0.001). A cutoff for the remodeling index of 1.162 corresponded to an exact ESUS prediction (area under the characteristic curve of the receiving operator) [AUC], 0.740) and was not significantly improved by the addition of other clinical variables.

This study was limited by a lack of histological validation data and a possible underestimation of the remodeling index due to the role of atherosclerosis.

The study’s authors concluded that their study “provides the first evidence of an etiological role of high-risk non-stenotic intracranial plaque in patients with ESUS”. However, they added, “The optimal prevention strategies in these patients remain unclear.”

reference

Tao L., Li XQ, Hou XW et al. Intracranial atherosclerotic plaque as possible cause of embolic stroke of undetermined source. J Am Coll Cardiol. 2021; 77 (6): 680- 691. doi: 10.1016 / j.jacc.2020.12.015