The Dark Side of the Moon - Significant Disagreements between Two-Dimensional and Three-Dimensional Echocardiographic Parameters of the Right Ventricular Function in Patients with Acute Myocardial Infarction.

Objectives: The present study aims to assess correlations and agreements between parameters and classification of the right ventricular (RV) function obtained by 2D echocardiography (2DE) - tricuspid annular plane systolic excursion (TAPSE), RV systolic wave velocity (S'T), fractional area change (FAC) and RV ejection fraction (3D RVEF) obtained by advanced 3D echocardiography (3DE).

Materials and methods: Patients admitted with acute myocardial infarction (AMI) were enrolled in the study after emergency coronary angiography. Standard 2DE and 3DE acquisitions were carried out in the first 48 hours since admission and later analysed offline by an advanced echocardiographer with five years of training in 2DE and three years of training in 3DE. Correlations between continuous echocardiographic variables were assessed using the Pearson correlation test. Patients were classified as having normal RV function or dysfunction based on current practice guidelines cut-off values and association between 2DE and 3DE parameters was assessed using the Pearson Chi-square test. Further, agreement between these categories was analysed using Cohen's k test.

Results: Sixty-three patients (52 males, mean age 56.8 ± 10.3 years) enrolled between December 2019 and June 2022 were analysed. The correlation between 3D RVEF and TAPSE, S'T and FAC was no statistically significant (r = 0.217, p = 0.088), weak (r = 0.385, p 0.001) and modest (r = 0.482, p = 0.002), respectively. Classification of RV function by FAC was the only 2DE parameter that exhibited statistically significant agreement [(χ2 (1, n=63) = 7.725, p=0.005)] and association (k = 0.3345, CI [-0.0747,0.5943]) when compared with 3D RVEF based classification.

Conclusions: Our study shows that, in a population of patients with acute myocardial infarction, measurements of RV function obtained by standard 2DE have varying degrees of correlation with 3D RVEF, and the subsequent classification of RV function using current cut-off values for these parameters leads to the misclassification of a significant number of patients.