Right ventricular ejection fraction measurements using two-dimensional transthoracic echocardiography by applying an ellipsoid model

Abstract

BackgroundThere is today no established approach to estimate right ventricular ejection fraction (RVEF) using 2D transthoracic echocardiography (TTE). The aim of this study was to evaluate a new method for RVEF calculations using 2D TTE and compare the results with cardiac magnetic resonance (CMR) imaging and tricuspid annular plane systolic excursion (TAPSE).MethodsA total of 37 subjects, 25 retrospectively included patients and twelve healthy volunteers, were included to give a wide range of RVEF. The right ventricle (RV) was modeled as a part of an ellipsoid enabling calculation of the RV volume by combining three distance measurements. RVEF calculated according to the model, RVEFTTE, were compared with reference CMR-derived RVEF, RVEFCMR. Further, TAPSE was measured in the TTE images and the correlations were calculated between RVEFTTE, TAPSE and RVEFCMR.ResultsThe mean values were RVEFCMR = 43 ± 12% (range 20–66%) and RVEFTTE = 50 ± 9% (range 34–65%). There was a high correlation (r = 0.80, p < 0.001) between RVEFTTE and RVEFCMR. Bland-Altman analysis showed a mean difference between RVEFCMR and RVEFTTE of 6 percentage points (ppt) with limits of agreement from −11 to 23 ppt. The mean value for TAPSE was 19 ± 5 mm and the correlation between TAPSE and RVEFCMR was moderate (r = 0.54, p < 0.001). The correlation between RVEFTTE and RVEFCMR was significantly higher (p < 0.05) than the correlation between TAPSE and RVEFCMR.ConclusionsThe ellipsoid model shows promise for RVEF calculations using 2D TTE for a wide range of RVEF, providing RVEF estimates that were significantly better correlated to RVEF obtained from CMR compared to TAPSE.Electronic supplementary materialThe online version of this article (doi:10.1186/s12947-017-0096-5) contains supplementary material, which is available to authorized users.

Mathematical modeling of cardiac function to evaluate clinical cases in adults and children

“…Accuracy of the right ventricular volume estimation from 2D echocardiography requires assumptions on the geometry of right ventricle [45]. Trimmed ellipsoidal geometries similar to the presented right ventricular model in this study to estimate right ventricular volume have already been used in 2D echocardiography [46,47]. Empirical coefficients expressing the irregularities in right ventricular shape are also used in 2D echocardiographic area-length methods estimating right ventricular volume [45].…”

Right ventricular ejection fraction as predictor of outcome in acute heart failure using RV ellipsoid model: A retrospective analysis of a prospective cross-sectional study

“…This model underestimates RV volumes when compared with MRI however this is generally the tendency with echocardiography. 17 , 23 , 27 Despite this RVEF from both modalities are comparable. 21 …”

“…7 An advantage of this method is that it does not require full visualization of the entire lateral aspect of the RV free wall in apical 4 chamber view which is relevant for dataset acquisition time in acutely unwell patients. 17 To our knowledge, this is the only study validating the clinical application of this model in the HF patient group. The stringent inclusion/exclusion criteria for this study and small number lost for full two-year follow-up provided us with a robust cohort of patients presenting with acute HF to validate both standard and new TTE parameters of RV function.…”

“…The RV ellipsoid model 16 has been validated against MRI in healthy individuals. 17 In short, the RV volume is calculated by assuming both left and right ventricles are parts of two ellipsoids with 3 common radii which can easily be measured on standard 2D TTE. Given that cardiac remodeling affects both ventricles in other conditions including valvular HF 18 , 19 we have assumed that such model is valid for patients with acute HF.…”

Three-dimensional echocardiography in the assessment of ventricular function in children: pros, cons, and hopes

“…It cannot be embraced or adequately represented by single-plane imaging; it also escapes simplifications offered by geometrical algorithms, especially in the case of deformation or enlargement of the chamber cavity. Because the assessment of RV volume and function is critical in the course of many cardio-pulmonary diseases, the search for the perfect imaging modality for that purpose might be compared to the "quest for the Holy Grail" [24][25][26][27].…”