Analytic Statistics. The diagnostic validity parameters will be calculated with 95% confidence intervals, using logistic regression models. The positive and negative predictive values will be calculated and the sensitivity and specificity will be estimated; receiver-operator curves (ROC) will also be analysed, with the calculation of the area under the curve. Diagnostic models with more than one parameter will be tested, using multivariable analysis, logistic and linear regression. For the analysis of agreement between the parameters obtained by ICG and echocardiography, the Bland-Altman method will be used with STATA® and R-project® software.