In-vivo mechanical characterization ofcoronary atherosclerotic plaques in livingswine using Intravascular Laser SpeckleImaging

The ability to evaluate the viscoelastic properties of coronary arteries is crucial for identifying mechanically unstable atherosclerotic plaques. Here, we demonstrate for the first time in living swine, the capability of intravascular laser speckle imaging (ILSI) to measure an index of coronary plaque viscoelasticity, τ, using a human coronary to swine xenograft model. Cardiac motion effects are evaluated by comparing the EKG-non-gated τ¯NG, and EKG-gated τ¯G among different plaque types. Results show that both τ¯NG and τ¯G are significantly lower in necrotic-core plaques compared with stable lesions. Discrete-point pullback measurements demonstrate the capability of ILSI for rapid mechanical characterization of coronary segments under physiological conditions, in-vivo.