Comparison of mitral annular displacement and global longitudinal strain imaging for predicting significant coronary atherosclerotic disease in patients of chronic stable angina pectoris.

Myocardial strain by two-dimensional speckle-tracking echocardiography (2D-STE) is a validated clinical index of myocardial deformation, for predicting CAD in patients with chronic stable angina pectoris (CSAP) with preserved ejection fraction (EF). However, it is complex, imaging dependant with intra and intervendor variability. The mitral annulus displacement (MAD) has been correlated to left ventricular (LV) longitudinal deformation and may be interchanged with strain imaging. This cross-sectional study was conducted on patients with suspected CSAP (n = 146) and preserved LVEF without wall motion abnormalities. We excluded patients with prior heart disease, ACS, arrhythmia, heart failure or poor imaging. GLS, Average MAD and normalized MAD were calculated using 2D-STE by automated function imaging. CAG was gold standard. MAD had significantly lesser dropout due to suboptimal imaging. Receiver operating characteristic (ROC) analysis showed that GLS had significantly better area under curve (AUC) compared to Normalised MAD and Average MAD (P = 0.035) in predicting significant CAD in patients of CSAP. The optimal cut-off of GLS, normalized MAD and Average MAD were ≥  - 20.67% (sensitivity 94.2%, specificity 86.7%), ≤ 15.22% (sensitivity 90.7%, specificity 80%) and ≤ 11.18 mm (sensitivity 83.7%, specificity 71.1%) respectively. GLS showed strong correlation with Normalised MAD (R = 0.669, P < 0.001) and good correlation to Average MAD (R 0.572, P < 0.001). Absolute GLS and Normalised MAD showed significant inverse correlation to SYNTAX score. GLS is a more accurate measure for predicting presence and severity of CAD then MAD however latter is a reliable simpler, robust, and expeditious tool with lesser dropouts. It can be at least of complementary value to other imaging markers for myocardial function when LV curvatures are poorly visualized or in busy outdoors with time constraint.