P1435 The impact of intermediate wall shear strain on changes of plaque morphology in CAD: A systematic review and meta-analysis

Background and Aim The experimental studies found that high wall shear strain (WSS) resulted in the development of more vulnerable plaque compared to low WSS. The aim of this meta-analysis is to assess the role of intermediate WSS on atherosclerotic plaque. Methods We systematically searched PubMed-Medline, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry from 1989 to May 2019 in order to select clinical trials and observational studies, which assessed the relationship between WSS measured by intravascular ultrasound (IVUS) and plaque morphology in CAD. Results A total of 32,083 segments were recruited in 7 studies with mean follow up 8.4 months. The pooled analysis showed that baseline low WSS is associated with similar plaque morphology to that with intermediate WSS: lumen area WMD 0.96 [-0.12 to 2.04, p = 0.08], plaque area WMD -0.43 [-0.09 to 0.13, p = 0.13], necrotic core area WMD -0.18 [-0.45 to 0.08, p = 0.18], dense calcium score WMD -0.12 [-0.26 to 0.02, p = 0.09] as well as fibrous WMD -0.35 [-0.89 to 0.19, p = 0.21] and fibro-fatty area WMD -0.05 [-0.12 to 0.02, p = 0.12]. At follow-up, the only difference found was an increase of fibrous WMD 0.08 [0.01 to 0.16, p = 0.04] and fibro-fatty area, WMD 0.07 [0.01 to 0.12, p = 0.02] in low WSS compared intermediate WSS. Conclusions Intermediate WSS group is associated with plaque features changes similar to those occurring with low WSS. This finding emphasis the role of IVUS in outcome of atherosclerotic plaque in CAD.