Effect of the local hemodynamic environment on the de novo development and progression of eccentric coronary atherosclerosis in humans: insights from PREDICTION.

BACKGROUND: Eccentric distribution of atheroma has been associated with plaques likely to rupture and cause an acute coronary syndrome, but the factors responsible for the development of eccentricity remain unknown. Endothelial shear stress (ESS) drives plaque formation. We aimed to investigate the role of the local ESS characteristics in the de novo development and progressive worsening of plaque eccentricity in humans. METHODS: Vascular profiling (3-vessel 3D coronary reconstruction by angiography/intravascular ultrasound, and blood flow simulation for ESS computation) was performed in 374 patients at baseline & 6-10 months follow-up. At baseline, we identified (i) disease-free segments (n=2157), and (ii) diseased regions of luminal obstructions (n=408). RESULTS: In disease-free regions, baseline low ESS magnitude (p<0.001), marked ESS circumferential heterogeneity (p=0.001), and their interaction (p=0.026) were associated with an increased probability of de novo eccentric plaque formation at follow-up. In diseased regions, baseline low ESS (odds ratio [OR]: 2.33, p=0.003) and large plaque burden (OR: 2.46, p=0.002) were independent predictors of substantially increasing plaque eccentricity index with worsening lumen encroachment. This combined outcome was more frequent in obstructions with both features vs. all others (33 vs. 12%; p<0.001). The incidence of percutaneous coronary intervention in worsening obstructions with increasing plaque eccentricity was higher (13.3 vs. 4.3%, p=0.011). CONCLUSIONS: The local hemodynamic environment has a critical effect on the development of eccentric coronary plaques at both an early and advanced stage of atherosclerosis. Local ESS assessment could help in predicting sites prone to plaque disruption and acute coronary syndromes in humans.