Diagnostic performance of right heart chambers strain parameters
We sought to evaluate the diagnosis performance of RV-FWS and RA-GS to predict categories of pulmonary hypertension severity. Receiver operating characteristic curve (ROC) analysis curves were generated and area under the curve (AUC) derived for RV and RA strain and compared with the Fraction of Shortening, TAPSE, TEI, which are commonly used echocardiographic parameters to evaluate right heart ventricle functionality. Furthermore, we sought to identify the optimal cut-off value of the strain parameters using the ”Youden method” from the R package ”Optimal cut points ” and evaluate the diagnostic test capacity, AUC, sensitivity, specificity, positive and negative predictive values (VPP, VPN, respectively) to predict pulmonary hypertension categories (14). Finally, we performed logistic regression models to assess the likelihood to have each pulmonary hypertension categories with their respective identified cut-off value. The goodness of fit of the logistic regression model was assessed using the Hosmer & Lemeshow test. All statistical analyses were performed using the R software (version 3.5.1) (15). A p -value <0.05 was considered as our statistically significant threshold.