Traditional and innovative echocardiographic parameters for the analysis of right ventricular performance in comparison with cardiac magnetic resonance

Aims: Right ventricle fractional area change (RVFAC), tissue Doppler and M-mode measurements of tricuspid systolic motion [tricuspid Sm and tricuspid annular plane systolic excursion (TAPSE)], and 3D echocardiography are the current non-invasive methods for the quantification of RV systolic function; RV deformation analysis by speckle-tracking echocardiography (STE) has recently allowed the analysis of RV performance. Using cardiac magnetic resonance (CMR) as the reference standard, this study aimed at exploring the correlation between the traditional (fractional shortening, s'RV, TAPSE) and innovative (strain) echocardiographic parameters and RV ejection fraction (RVEF) measured by CMR.

Methods and results: CMR and transthoracic echo-Doppler were performed in 63 patients referred for clinical assessment. Twenty-one presented the suspicion of myocarditis, 8 presented idiopathic dilated cardiomyopathy, 10 hypertrophic cardiomyopathy, 10 arrhythmogenic right ventricular dysplasia (ARVD), 5 infiltrative cardiomyopathy, and 9 other reasons. RVEF was measured by magnetic resonance imaging (MRI). RVFAC, tricuspid S', and TAPSE were calculated in all patients. RV longitudinal strain (RVLS) by STE was assessed by averaging RV free-wall segments (free-wall RVLS) and by averaging all segments (global RVLS). The ROC analysis was applied for the assessment of diagnostic accuracy. Good correlations were found for TAPSE, tricuspid S', and global RVLS with RVEF (r = 0.45, r = 0.52, and r = -0.71, respectively; P = 0.01 for all). Close correlations between free-wall RVLS and RVFAC with RVEF were found (r = -0.86 and r = 0.77, respectively; P < 0.0001 for both). Furthermore, free-wall RVLS demonstrated the highest diagnostic accuracy [area under curve (AUC) 0.92] and good sensitivity and specificity of 96 and 93%, respectively, to predict reduced RVEF <45%, using a cut-off value of less than -17.0%.

Conclusion: In a heterogeneous group of patients referred to CMR evaluation, conventional (TAPSE, FAC, and tricuspid S') and novice (2D speckle-tracking-derived longitudinal strain) parameters of RV systolic function were compared and correlated with RVEF measured by MRI. All tested parameters were found to be independent predictors of reduced RVEF (<45%), but the strongest correlation was seen for the RV free-wall longitudinal strain.