Standardizing plaque impact on overall coronary hemodynamics using a binomial equation based on the equivalent energy loss.

Abstract

This study proposes a novel method for evaluating the risk of adverse events (AE) in patients with coronary stenosis based on the morphology and hemodynamics along a whole coronary artery. Twenty-eight specific coronary artery tree models with different stenotic degrees are established from the CCTA images and divided into AE group and Non-AE group. Pressures are obtained by computational fluid dynamics method. The left anterior descending branches are divided equidistantly along the centerline. The characteristic diameters of each segment are measured and normalized to standard the patient-specific coronary arteries as characteristic straight pipes with variable cross-sections. Based on the energy loss theory, the normalized characteristic diameters ( [Formula: see text] ) and pressure drops (Δp_i) of each segment are fitted to a binomial equation. The differences of binomial coefficients between the two groups are compared. The results show that: [Formula: see text] changes suddenly in the lesions part and Δp_i fluctuates in the posterior half of lesions part and its upstream and downstream. There is a significant difference in the ratio of two binomial equation coefficients, which represents the combination of local resistance coefficient, length, flow rate and maximum characteristic diameter of the standard pipe (0.93 ± 0.16 vs. 1.42 ± 0.58, p = 0.0003). This method emphasizes the influences of stenosis on the whole coronary artery, and reflects the cardiac function requirements of the stenotic coronary artery from the patient itself. The ratio of two binomial equation coefficients can supplement the information obtained by existing detection methods and may help evaluate the risk of AEs.