Colocalization of Coronary Plaque with Wall Shear Stress in Myocardial Bridge Patients

Area of Science:

• Cardiovascular Medicine
• Biomedical Engineering
• Medical Imaging

Background:

• Patients with myocardial bridges (MBs) exhibit a higher incidence of atherosclerosis.
• Wall shear stress (WSS) is associated with coronary artery disease plaque, but its role in MB patients is understudied.
• Investigating WSS in MB patients is crucial for understanding plaque development.

Purpose of the Study:

• To employ a multi-scale computational fluid dynamics (CFD) framework to simulate hemodynamics in patients with myocardial bridges (MBs).
• To investigate the co-localization of wall shear stress (WSS) and atherosclerotic plaque within MB patients.
• To explore the potential of WSS as a non-invasive marker for plaque burden in MB patients.

Main Methods:

• Reconstructed 3D models from CCTA, IVUS, and catheter angiograms for 10 symptomatic MB patients with proximal plaque.
• Performed CFD simulations to compute WSS proximal to, within, and distal to the MB.
• Quantified plaque area from IVUS images and compared it with absolute and patient-normalized WSS.

Main Results:

• WSS was significantly lower in the proximal segment compared to the bridge segment (6.1 ± 2.9 vs. 16.0 ± 7.1 dynes/cm², p < 0.01).
• Plaque area and burden peaked 1-3 cm proximal to the MB entrance, near the first diagonal branch.
• Normalized WSS demonstrated a moderate, statistically significant correlation with plaque area (r = 0.41, p < 0.01).

Conclusions:

• WSS can be non-invasively measured in MB patients and serves as a surrogate marker for plaque area.
• CFD simulations may enable non-invasive assessment of plaque extent in MB patients.
• This approach can help identify patients requiring closer monitoring or specific medical management.