Abstract 17129: Risk Stratification Using Myocardial Peak Longitudinal Strain on Speckle Tracking Transthoracic Echocardiogram to Predict Major Adverse Cardiac Events in Non Ishchemic Hypertrophic Cardiomyopathy Subjects Confirmed by 320 Slice CT

Abstract

Purpose: To predict occurrence of major adverse cardiac event (MACE) in non ischemic hypertrophic cardiomyopathy (HCM) subjects, we compared myocardial regional maximum (max PLS) and global peak longitudinal strain (GPLS) values in left ventricular myocardium (LVM) using two dimensional speckle tracking transthoracic echocardiography (TTE)

Methods: 44 consecutive symptomatic HCM subjects (28 males; mean age, 61.4 yrs) undergoing 320-slice CT (Aquilion one), in which no significant coronary arterial stenosis was observed, and TTE (iE-33) within 12 months were enrolled and followed for a median of 18 months. On TTE, regional PLS in each segment of LVM among 17 lesions by AHA were calculated and average of all regional PLS expressed as global PLS.

Results: In 44 HCM subjects, 93.0 % oflesions yielded good tracking on TTE. 13 subjects had MACE. Max and global PLS were significantly greater in HCM subjects with MACE than in those without MACE (-2.9±1.3 % and -3.3±1.9 % for max PLS and -8.2±2.0 % and -10.6±2.5 % for global PLS, respectively, both P<0.001). Receiver operating characteristic curves of max and global PLS on TTE revealed areas under curve (AUC) of 0.560 and 0.788, respectively and a best cutoff point of -4.43 % (sensitivity 100 %, specificity 35.5 %) and -9.85 % (sensitivity 92.3 %, specificity 71.0 %), respectively to distinguish subjects with and without MACE. By Kaplan Meier analysis, MACE was more frequent in HCM subjects with global PLS ≥-9.85 % than in those with global PLS <-9.85 % (P<0.01) and in HCM subjects with max PLS ≥-4.43 % than in those with max PLS <-4.43 % (P=0.04) during observation period, respectively. A Cox proportional hazard model revealed that global PLS ≥-9.85 % were greater predictors of MACE (Hazard ratio 18.7, 95 % confidence interval 2.06-169.9, P=0.046) than max PLS (P=NS).

Conclusions: Global PLS on speckle tracking TTE (-9.85 % in this study) provides useful information non invasively to accurately predict MACE in non ischemic HCM subjects.