22. Comparison of conventional echocardiographic parameters of rv systolic function with cardiac magnetic resonance imaging

Abstract

Nowadays, cardiac magnetic resonance (CMR) imaging is considered the gold standard for quantification of RV size and function. Multiple 2D Echocardiography (echo) parameters are recommended for quantification of systolic RV function including Fractional Area Change (FAC%), tricuspid annular plane systolic excursion (TAPSE) and Tissue Doppler velocity (TDI) of tricuspid annulus. The aim of our study was to compare the conventional 2-D echocardiographic parameters of RV systolic function with CMR derived RVEF and stroke volume (SV). The echo and cardiac magnetic parameters to assess the right ventricular function are different. Consecutive patients referred to CMR for RV assessment from January 2011 to December 2014 were screened. 69 patients with CMR and adequate echo were selected. 20 subjects with normal CMR were enrolled as a control group. Quantitative 2-D echo measures were compared with CMR RVEF (%) and SV (ml). The comparison was made using linear correlation for the echo variables with CMR variables. The mean age of patients was 38.2 + 5.4 (51% females) were enrolled. 84.1% of patients had normal RVEF by CMR. In patients, FAC% but not TAPSE or annular TDI, correlated with CMR derived RVEF (R = 0.45, p = 0.0001) with fair agreement (kappa 0.43). However, FAC% did not correlate with CMR RV stroke volume. In contrast, in normal subjects, TAPSE had the best correlation with CMR derived RVEF (R = 0.67, p = 0.0001). In patients, CMR reclassified RV function assessed by FAC% in 11 (16%). 6 (8%) patients who had abnormal RV function by FAC% were reclassified as normal while 5 (7%) with normal RV function by FAC% were reclassified as abnormal. In normal subjects, however, only one with abnormal RV function by TAPSE was reclassified as normal by CMR. The current quantitative 2-D echo parameters of RV systolic function assessment correlate poorly with CMR measured RVEF and SV and behave differently in comparison with CMR in patients with normal and abnormal RV function. CMR should be utilized more often to measure RVEF and volumes to complement routine 2-D echocardiography measurements for comprehensive and accurate evaluation of RV systolic function.