The carotid plaque imaging in acute stroke (CAPIAS) study: protocol and initial baseline data

Area of Science:

• Neurology
• Cardiovascular Medicine
• Radiology

Background:

• Up to 30% of ischemic stroke cases lack a clear cause (cryptogenic stroke).
• Non-stenosing atherosclerotic plaques or low-grade carotid stenosis may underlie some cryptogenic strokes.
• The CAPIAS study focuses on American Heart Association lesion type VI (AHA-LT VI) carotid plaques.

Purpose of the Study:

• To determine the frequency and characteristics of AHA-LT VI carotid plaques in cryptogenic stroke patients.
• To compare AHA-LT VI plaque prevalence ipsilateral to stroke versus contralateral and in patients with known stroke etiologies.
• To assess the long-term clinical and radiological consequences of these plaques.

Main Methods:

• Prospective, multicenter study (CAPIAS) enrolling 300 patients (>49 years) with cryptogenic stroke and non- to moderate (<70% NASCET) internal carotid artery stenosis.
• High-resolution black-blood carotid MRI at baseline and 12-month follow-up to assess plaque characteristics.
• Primary outcome: prevalence of ipsilateral AHA-LT VI plaques. Secondary outcomes: stroke recurrence, new MRI lesions, plaque feature influence on disease progression.

Main Results:

• Prevalence of complicated AHA-LT VI plaques in cryptogenic stroke patients compared to controls.
• Association of AHA-LT VI plaques with ischemic event recurrence up to 36 months.
• Rates of new ischemic lesions on cerebral MRI after 12 months.

Conclusions:

• The CAPIAS study will offer insights into the role of non-stenosing carotid plaques in cryptogenic stroke.
• Results may refine understanding of stroke mechanisms and diagnostic approaches.
• Findings could form the basis for targeted interventional studies in stroke prevention.