P5977Predicting significant ventricular arrhythmias in STEMI patients: never-ending challenge, still more place for myocardial deformation imaging?

Abstract

Background Malignant ventricular arrhythmias in STEMI patients carry ominous prognosis including sudden cardiac death (SCD). According to the current guidelines only EF<35%, 40 days after STEMI, is indication for ICD implantation. Recently, index of myocardial dispersion (IMD) estimated by myocardial deformation imaging (speckle tracking echocardiography) was documented to provide better risk stratification. Aim To define whether quantification of myocardial mechanics early after pPCI using modern echocardiography offers information more to predict malignant arrhythmias during the first year after STEMI. Methods In the 226 consecutive STEMI patients (pts) 57.8±10.4yr, 71.7% males, in PREDICT-VT study (NCT03263949) treated with pPCI early echo (5±2 days) was done including conventional parameters and comprehensive speckle tracking LV deformation analysis with longitudinal (L), circumferential (C) strain (S;%) and strain rate (SR, 1/sec) and rotational LV mechanics. ROC analysis was performed to identify the best parameters to predict composite end-point defined as secondary VF, sustained/non-sustained VT and SCD, 48h after pPCI and during the first year of follow up. Results Twenty two patients (9.7%) reached the end-point. Classical parameters of LV systolic function, including LVEF, wall motion score index; global, systolic LS, CS and parameters of diastolic dysfunction were not significant predictors of the malignant arrhythmias. Early L SR, systolic C SR, IMD of global rotation and late rotation rate predicted the primary end-point (table). Parameter ROC area 95% CI p Cutt-off Sens Spec Longirudinal mechanics SR E (1/sec) 0.687 0.577–0.796 0.019 0.69 64 65 IMD S (ms) 0.752 0.666–0.838 0.002 66.1 71 72 Circumferencial mechanics SR S (1/sec) 0.732 0.613–0.852 0.002 −1.22 71 67 Rotational mechanics Global IMD (ms) 0.329 0.177–0.481 0.036 82.9 63 62 Late rotation rate IMD (ms) 0.318 0.196–0.442 0.026 41.1 65 64 Conclusion Myocardial deformation imaging offers deeper insight into complex mechanical abnormalities during LV contraction and relaxation in longitudinal, circumferential and rotational directions (impaired and asynchronous deformations) in STEMI patients and predicts serious arrhythmic events.