Abbreviated Cardiovascular MRI for Enhanced Etiology Diagnosis in Acute Ischemic Stroke Patients
openNHLBI - National Heart Lung and Blood Institute
ABSTRACT
The overarching goal of this project is to develop an abbreviated cardiovascular magnetic resonance (aCMR)
imaging solution for time-efficient, cost-effective etiology diagnosis of acute ischemic stroke (AIS). Stroke is the
second leading cause of death and the third leading cause of disability worldwide. About 87% of all strokes are
ischemic. Causes of AIS include large artery atherosclerosis, small artery disease, cardioembolism, and some
unusual conditions (e.g., hypercoagulability and dissection). Rapidly and correctly identifying the cause of AIS is
crucial for treatment decisions to prevent stroke recurrence. However, the routine etiology workup for AIS
remains limited. First, standard evaluation, including history collection, physical examination, laboratory tests,
and step-wise imaging workup, fails to identify a definitive cause in 20-30% of ischemic strokes, leading to a
diagnosis of cryptogenic stroke. Second, etiology classification based on standard evaluation may be incorrect,
with reported misclassification rates ranging from 14% to 55%. Third, although advanced evaluation may be
pursued at specialized stroke centers when standard evaluation fails, the rate of cryptogenic strokes remains as
high as 10-15%, also underscoring the need for further technical innovation. Nevertheless, the overall multi-step,
multi-modality imaging paradigm in the current stroke etiology workup inevitably extends the diagnostic timeline,
delays the initiation of effective intervention, and imposes a substantial burden on both patients and the
healthcare system. MR has shown great potential for multi-station etiology evaluation, particularly within one
examination, which would substantially complement and expedite the current diagnostic workup. To address the
above unmet clinical needs, we will develop a 10-minute-long aCMR solution that can be seamlessly integrated
into the initial brain MR examination typically performed 24-48 hours after AIS admission. It features two-station
scanning (based on our novel joint head-neck vessel wall imaging technique and joint heart-aorta multi-
dimensional imaging technique), superb image contrast and time efficiency, and a light-weight blanket carotid-
chest coil design for easy patient setup, which will collectively contribute to invaluable multifaceted diagnostic
information with minimal interference with the current workflow. This project will deliver two optimized MR
techniques as the core of aCMR in Aim 1 followed by a clinical study to assess its impact on stroke etiology
diagnosis in Aim 2. Abbreviated MR protocols have gained popularity in other fields due to their cost-
effectiveness, yet no such protocol currently exists for stroke etiology evaluation. This project will fill this critical
gap by pioneering a streamlined, high-impact approach. If successfully validated, the aCMR-based imaging
paradigm is expected to significantly enhance AIS care by improving the accuracy and efficiency of etiology
diagnosis, reducing rates of cryptogenic stroke diagnosis, and effectively guiding treatment decisions for
secondary stroke prevention.
Up to $451K
health research