Abstract 10837: Left Ventricular Dyssynchrony Estimated by 3D Speckle Tracking Echocardiography Acutely Onset after ST-Elevation Myocardial Infarction Predicts Final Infarct Size and Remodeling

Abstract

<Backgrounds> LV dyssynchrony, estimated by strain immediately after AMI, was reported as a predictor of LV remodeling.

<Methods> The study included 80 consecutive patients (65men, 65years, maxCPK = 3123 ± 3977IU/l) presenting with a first ST-elevation AMI (STEMI) who underwent primary PCI within 12 hours of onset. Within 24 h of PCI, 2D and 3D speckle tracking echocardiography were performed by E33 and Q-lab ver 8.1 (CMQ, Philips). 3D speckle tracking was analyzed by 4D LV-Analysis (TOM-TEC, Germany). The standard deviation (SD) of time to regional peak 3D speckle area strain (3Darea-SD), 3D circumferential strain (3DCirc-SD) and 3D longitudinal strain (3Dlong-SD) for all 16 segments were assessed. The absolute differences in time-to peak circumferential (Tm-circ), and longitudinal (Tm-long) strains were assessed in 2D speckle tracking analysis. Final infarct size was defined using Tc99m-sestamibi as the total area of <50%uptake area at 2 weeks. Echocardiography was repeated 12 months later and LV remodeling was defined as an absolute increase in LVEDV more than 20%. Patients with LBBB/RBBB were excluded.

<Results> Each 3D dyssynchronous indexes had better correlation with infarct size (3Darea-SD,3Dcirc-SD,3Dlong SD;r=0.53,0.55,0.48,respectively,p<0.0001) compared with 2D dyssynchronous indexes(Tm-circ,Tm-long;r=0.32,0.35,p=0.01). Table shows univariate and multivariate analysis for the prediction of LV remodeling. Twenty-one patients had LV remodeling at the 12-month. Table shows the logistic regression analysis. Univariate analysis demonstrated that each 3D dyssynchronous indexes were the significant predictors. Stepwise multivariate analysis showed that 3DCirc-SD was stronger than 2DTm-Circ.

<Conclusions> In patients with a first STEMI, LV dyssynchrony assessed by 3D speckle tracking echocardiography immediately after PCI can predict final infarct size and predict LV remodeling despite having narrow QRS.