Correlation between Global Longitudinal Strain and Ischemic Burden from Myocardial Perfusion Imaging in Multivessel Coronary Artery Disease Patients

Abstract

Background: Global Longitudinal Strain (GLS) is a direct echocardiographic assessment of myocardial fiber deformation performed by speckle-tracking echocardiography that can better reflect ischemic and infarct areas and left ventricular function. Ischemic burden is a measurement of ischemic myocardium percentage and can be used to determine the management strategy of Multivessel Coronary Artery Disease (MVCAD). We aimed to investigate the value of GLS to predict the ischemic burden as detected by SPECT Myocardial Perfusion Imaging (MPI)
 Method: A cross-sectional study of patients with Multivessel Coronary Artery Disease who underwent Cardiac SPECT were included. GLS is assessed using the Automated Function Imaging (AFI) technique that is performed on the same day as the SPECT examination. Ischemic burden was measured by SPECT MPI using semi-quantitative scores on 17-segment assessment according to standard nomenclature and interpreted as small and moderate-large ischemic burden. 
 Result: Total of 52 patients (40 males, mean age 56 ± 6.5 years). There was negative correlation with good strength between GLS value and ischemic burden (r = -0.706, P < 0.001). Using ROC analysis, the optimal cut off value of GLS was < (-13%) that yielded the highest sensitivity and specificity to discriminate between small and moderate-large ischemic burden. Sensitivity, specificity, positive and negative predictive value of GLS ≤(-13%) to predict moderate-large ischemic burden as detected by SPECT analysis were 80%, 75%, 67%, and 86%, respectively.
 Conclusion: A GLS value is a reliable parameter with good diagnostic value to predict small ischemic burden (<10%) as detected by SPECT MPI. This parameter could also be applied to determine the management strategy of Multivessel Coronary Artery Disease (MVCAD) patients in daily practice.