Measurement of left ventricular torsion by 2-dimensional speckle-tracking imaging in patients with chronic cor pulmonale

Objective To evaluate the sensitive indicator of left ventricular rotation/torsion assessed by two-dimensional speckle tracking imaging (STI) and Logistic regression analysis, and to investigate the clinical value of the sensitive indicator for assessment of left ventricular dysfunction in patients with chronic cor pulmonale (CCP). Methods 36 patients with CCP (CCP group) and 38 healthy controls (control group) were included in this study. Imaging in parasternal short-axis view (in basal and apical level) were selected. Parasternal short-axis views at mitral valve and apical levels were collected. Basal peak rotation, apical peak rotation, peak torsion, basal end-systolic rotation, apical end-systolic rotation and end-systolic torsion were measured with Echo PAC software. Relevant indicators of left ventricular rotation/torsion were selected by using logistic regression analysis and the regression equation was established. Optimal values of specific parameters (Peak torsion and end-systolic torsion) were calculated with receiver-operating characteristic (ROC) curve. Results Specific parameters of rotation/torsion were significantly reduced in patients with CCP as compared with controls (all P<0.01). Logistic regression analysis showed that end-systolic torsion and peak torsion were correlated with CCP (OR=0.473 and 0.706, P=0.007 and 0.011). Cut-off value of peak torsion for predicting left ventricular dysfunction was 12.070°, the area under the ROC curve (AUC) was 0.819 (95%CI: 0.683-0.956), the sensitivity was 84.6%, and the specificity was 73.9%. Cut-off value of end-systolic torsion for predicting left ventricular dysfunction was 10.680°, AUC was 0.875(95%CI: 0.744-1.000), the sensitivity was 84.6%, and the specificity was 91.3%. Conclusions Two-dimensional speckle tracking imaging can sensitively assess left ventricular torsion and evaluate the left ventricular dysfunction in patients with CCP. Key words: Pulmonary heart disease; Echocardiography; Ventricular function, left