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Updated: May 19, 2026
Evaluation of Blood-Brain Barrier Breakdown in a Mouse Model of Mild Traumatic Brain Injury
Published on: October 18, 2024
Blood-brain barrier disruption after cardiac surgery
J G Merino1, L L Latour, A Tso
1Section on Stroke Diagnostics and Therapeutics, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA. merinoj@ninds.nih.gov
Background And Purpose:
CNS complications are often seen after heart surgery, and postsurgical disruption of the BBB may play an etiologic role. The objective of this study was to determine the prevalence of MR imaging-detected BBB disruption (HARM) and DWI lesions after cardiac surgery.
Materials And Methods:
All patients had an MRI after cardiac surgery. For half the patients (group 1), we administered gadolinium 24 hours after surgery and obtained high-resolution DWI and FLAIR images 24-48 hours later. We administered gadolinium to the other half (group 2) at the time of the postoperative scan, 2-4 days after surgery. Two stroke neurologists evaluated the images.
Results:
Of the 19 patients we studied, none had clinical evidence of a stroke or delirium at the time of the gadolinium administration or the scan, but 9 patients (47%) had HARM (67% in group 1; 30% in group 2; P = .18) and 14 patients (74%) had DWI lesions (70% in group 1; 78% in group 2; P = 1.0). Not all patients with DWI lesions had HARM, and not all patients with HARM had DWI lesions (P = .56).
Conclusions:
Almost half the patients undergoing cardiac surgery have evidence of HARM, and three-quarters have acute lesions on DWI after surgery. BBB disruption is more prevalent in the first 24 hours after surgery. These findings suggest that MR imaging can be used as an imaging biomarker to assess therapies that may protect the BBB in patients undergoing heart surgery.
Insights
Nearly half of cardiac surgery patients show blood-brain barrier disruption (HARM) and most have diffusion-weighted imaging (DWI) lesions, indicating potential brain injury after surgery.
Area of Science:
- Neurology
- Cardiovascular Surgery
- Radiology
Background:
- Central nervous system (CNS) complications are common after cardiac surgery.
- Disruption of the blood-brain barrier (BBB) is a potential cause of these postsurgical CNS issues.
Purpose of the Study:
- To determine the prevalence of BBB disruption (HARM) and diffusion-weighted imaging (DWI) lesions detected by MRI after cardiac surgery.
Main Methods:
- MRI scans were performed on patients post-cardiac surgery.
- Gadolinium contrast was administered either 24 hours or 2-4 days after surgery.
- High-resolution DWI and FLAIR images were obtained and evaluated by stroke neurologists.
Main Results:
- 47% of patients exhibited HARM, with higher prevalence when gadolinium was given earlier (67% vs 30%).
- 74% of patients showed acute DWI lesions.
- HARM and DWI lesions were not always concurrent, suggesting distinct pathophysiological processes.
Conclusions:
- Nearly half of patients undergoing cardiac surgery demonstrate BBB disruption (HARM).
- Three-quarters of patients have acute DWI lesions post-surgery.
- BBB disruption is more frequent within 24 hours after surgery, suggesting early intervention potential.
