Diagnostic accuracy of global myocardial deformation indexes in coronary artery disease: a velocity vector imaging study

The aim of our study was to assess the diagnostic accuracy of a global longitudinal strain and strain rate (GLS, GLSR) and mean radial strain and strain rate (MRS, MRSR) of the left ventricle to predict multivessel disease. In 113 patients, who underwent coronary angiography, left ventricular deformation was analysed by speckle-tracking based velocity vector imaging. In three standard apical views strain and strain rate curves were generated corresponding with two opposite basal, mid, and apical segments. The negative peaks of systolic strain and strain rate from 18 curves were averaged as GLS and GLSR. Similarly, in short axis view 6 negative systolic peaks were averaged and considered as MRS and MRSR. Four subgroups were defined: (1) without significant coronary stenosis, 0-vessel disease (0VD), (2) single-vessel disease (1VD), (3) double-vessel disease (2VD), and (4) triple-vessel disease (3VD). In comparison with patients without significant coronary artery disease, all deformation indexes were significantly decreased in patients with 3VD. The left ventricular ejection fraction (LVEF) and wall motion score index (WMSI) showed lower significance level as deformation parameters. MRSR was the strongest predictor of multivessel disease. Receiver-operating characteristic curves (ROC) showed that MRSR had the highest diagnostic accuracy. Comparing ROC areas, MRSR had significantly higher diagnostic accuracy than LVEF and WMSI. The results of our study show that global deformation indexes have a good diagnostic accuracy in differentiating multivessel disease. MRSR tended to be better in identification of 3VD than traditional indexes of global and regional left ventricular function.