Stroke with covert brain infarction indicates high vascular risk

Chronic covert brain infarction (CBI) was present in more than one-third of patients with a first-ever acute ischaemic stroke in a single-centre cohort study. These patients represent a subgroup with a high vascular risk.

Of patients with a first-ever acute ischaemic stroke, 1 in 3 has an additional chronic CBI on acute imaging. Dr Thomas Meinel (Bern University Hospital, Switzerland) and his group set out to assess the frequency, imaging phenotypes, and distribution of CBI in patients with a first-ever clinically evident acute ischaemic stroke; determine the vascular risk factor profile according to CBI phenotypes; and disentangle the association of CBI and undifferentiated white matter hyperintensities (WMH) [1]. They assessed 1,546 consecutive patients with first-ever acute ischaemic stroke with MRI on admission between 2015 and 2017.

A total of 950 CBI lesions were found in 574 of 1,546 patients (37%). The most frequent CBI locations were cerebellar (31%), subcortical supratentorial (31%), and cortical (24%). CBI phenotypes included cavitary lesions (49%), combined grey and white matter lesions (30%), grey matter lesions (13%), and large subcortical infarcts (7%). Vascular risk profile and WMH severity (19% in absence of WMH, 63% in severe WMH; P<0.001) were associated with CBI. NIH Stroke Scale scores on admission were higher in patients with an embolic CBI phenotype (median NIHSS 5; P=0.025).

Dr Meinel concluded that additional CBI indicates an elevated vascular risk, as several vascular risk factors and WMH severity are associated with CBI. Different phenotypes of CBI were associated with differing risk factor profiles, potentially pointing towards discriminative ischaemic stroke aetiologies. For example, a consistent association was observed between cortical CBI and atrial fibrillation (adjusted OR 2.03). At least 25% of CBIs found in this stroke population were not part of the small vessel disease spectrum. “Although not incorporated in current guidelines for acute stroke management, chronic CBI is associated with certain stroke subtypes and might be used to develop individualised diagnostic work-up and therapeutic approaches for patients with a first-ever acute stroke,” Dr Meinel elaborated.

In a separate talk on CBI and precision medicine [2], Dr Meinel gave the following take-home messages:

• CBI is the most frequent incidental finding on brain MRI, present in 30% of 70-year-old patients. This percentage is higher in cardiovascular risk populations.
• Look for CBI and then act upon them: as a neuro-radiologist, describe them according to the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE), but also when they are not part of the small vessel disease spectrum; ask the patient if it was truly covert and if full workup was done; were there covert deficits, such as visual field defects; assess and treat modifiable cardiovascular risk factors; assess depression, cognition, and mobility.
• CBI can be used as a prognostic tool in, for example, atrial fibrillation.
• Incident CBI offers the opportunity to reduce cardiovascular morbidity and mortality.

1. Vynckier J, et al. Phenotypes of chronic covert brain infarction in first-ever ischemic stroke patients – a cohort study. OPR-128, EAN 2021 Virtual Congress, 19–22 June.
2. Meinel T. Covert brain infarction: Towards precision medicine in research, diagnosis, and therapy for a silent pandemic. SYMP11-1, EAN 2021 Virtual Congress, 19–22 June.

 

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Posted on 18 August 202122 February 2024