Introduction:
Right Ventricular (RV) function has significant prognostic importance for a variety of heart diseases and their clinical outcomes. RV function assessment is frequently conducted for staging and prognostic purposes, especially in cardiac diseases with a right heart involvement. Of note, RV dysfunction can affect the left ventricular (LV) Forward stroke volume by restricting the preload of LV, as well as alter LV systolic and diastolic function secondary to the interaction with the interventricular septum and pericardium, and eventually lead to biventricular failure . This is ascribed to the physiological function of RV to maintain adequate pulmonary perfusion pressure and a low systemic venous pressure.
Current clinical management has largely relied on non-invasive modalities like echocardiography for RV function assessment. Conventionally, one-dimensional echocardiography parameters such as tricuspid annular peak systolic excursion (TAPSE), lateral tricuspid annular systolic velocity (S’) and two-dimensional (2D) parameters such as RV functional area change (FAC) are being used. However, these parameters are still subject to limitations due to the complex anatomical structure and geometric shape of RV. The RV rendering volume readings by echocardiography are susceptible to errors due to the distinctive cavity geometry of the RV as opposed to the ellipsoid shape of LV, and the change in longitudinal contraction pattern in diseased states.
Cardiac magnetic resonance imaging (CMR) is considered as the gold standard for RV function assessment. CMR provides accurate results in quantifying heart function and structure and has become widely used for different heart diseases. In RV assessment, RV volumes obtained by CMR indicate a strong correlation with clinical assessment, and there is an excellent accuracy and consistency of the volume measurements. Despite the high accuracy and reproducibility, CMR has its constraints including cost, availability, time-consuming, and skill-consuming as it requires drawing endocardial contour manually, and also requires defining the most basal short-axis slice and the endocardial border, which is complicated by thin free wall and extensive trabeculations .
With the recent advance of speckle-tracking echocardiography, direct measurement of myocardial deformation by strain becomes a great alternative tool for RV function assessment . RV strain has been reported as a technique with high accuracy and reproducibility and is closely correlated with prognosis. However, only limited studies have compared all these parameters with CMR. The purpose of this study is to evaluate the accuracy of echocardiographic parameters in assessing RV systolic function and specifically to compare standard echo parameters to RV strain imaging and MRI to identify the best echo parameter(s) to assess RV systolic function