Vulnerable coronary plaque identification: Murray's flow ratio and radial wall strain compared with IVUS-NIRS...

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Coronary vulnerable plaque (VP) identification is critical for preventing acute cardiovascular events.
• Intravascular ultrasound with near-infrared spectroscopy (IVUS-NIRS) is the reference standard for assessing plaque vulnerability using lipid core burden index (LCBI) and plaque burden (PB).
• Murray's flow ratio (μFR) and maximal radial wall strain (RWSmax) are novel angiography-derived parameters with potential for stratifying plaque risk.

Purpose of the Study:

• To evaluate the ability of μFR and RWSmax to identify VP as defined by IVUS-NIRS criteria.
• To compare the diagnostic performance of angiography-derived parameters against IVUS-NIRS in VP detection.

Main Methods:

• Retrospective analysis of 89 lesions from patients who underwent IVUS-NIRS.
• VP defined by IVUS-NIRS: maxLCBI4mm ≥325 and PB ≥70%.
• Offline calculation of μFR and RWSmax, followed by correlation analysis and receiver operating characteristic (ROC) curve evaluation for VP diagnostic performance. Multivariable analysis was performed to identify independent predictors.

Main Results:

• μFR showed an inverse correlation with maxLCBI4mm (r=-0.452) and PB (r=-0.276).
• RWSmax demonstrated a positive correlation with maxLCBI4mm (r=0.597) and PB (r=0.294).
• ROC analysis indicated good accuracy for VP identification by both μFR (AUC=0.71) and RWSmax (AUC=0.80). RWSmax remained an independent predictor in multivariable analysis, while μFR did not.

Conclusions:

• Both μFR and RWSmax correlate with key IVUS-NIRS parameters (PB and maxLCBI4mm).
• RWSmax exhibits independent predictive capability for identifying vulnerable coronary plaques (VP).
• Angiography-derived RWSmax shows promise as a non-invasive tool for VP risk stratification.