Correlation Of Common Echocardiographic Variables With Regional Right Ventricular Strain

Background Speckle tracking strain (STs) imaging provides an angle independent global as well as regional assessment of the right ventricle (RV). Even though regional differences do exist with regards strain generation between the RV free wall (RVFw) and interventricular septum (IS), which of these STs measures correlates best with measures of RV and left ventricular function have not been previously assessed. Methods A retrospective analysis was conducted on 110 patients who had RV longitudinal STs acquired from all 3 RVFw and 3 IS regions using the General Electric automated functional imaging (AFI) tool. In addition, all these patients had RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), TA tissue Doppler imaging systolic velocity (TA TDI s’) and mitral annular (MA) TDI s’ values. Results Mean, standard deviation and range values for each value of the studied population (mean age 49 ± 16 years with 46 males) are shown in Table 1. Given the well-known differences between both mid wall RVFw and mid IS wall strain when analyzing the RV; we first performed a multivariate analysis using the basal RVFw strain, then the mid RVFw strain, and finally the mid IS wall strain. As expected, TAPSE correlated well with TA TDI s’ (R2=0.9866) (Figure 1). RV mid strain (R2=0.9236) and IS mid strain (R2=0.9268) correlated better with TAPSE as compared to the correlation between RV basal-apex (R2=0.0257) and IS basal-apex (R2=0.0119) and TAPSE (Figure 2). Conclusions The differences observed could be physiologically and anatomically explained based on our current understanding of RV muscle fiber arrangement and common attachment into the IS. Further research is now needed to better characterize how both RV and LV function in different clinical entities modify our interpretation of global and regional RV STs. Speckle tracking strain (STs) imaging provides an angle independent global as well as regional assessment of the right ventricle (RV). Even though regional differences do exist with regards strain generation between the RV free wall (RVFw) and interventricular septum (IS), which of these STs measures correlates best with measures of RV and left ventricular function have not been previously assessed. A retrospective analysis was conducted on 110 patients who had RV longitudinal STs acquired from all 3 RVFw and 3 IS regions using the General Electric automated functional imaging (AFI) tool. In addition, all these patients had RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), TA tissue Doppler imaging systolic velocity (TA TDI s’) and mitral annular (MA) TDI s’ values. Mean, standard deviation and range values for each value of the studied population (mean age 49 ± 16 years with 46 males) are shown in Table 1. Given the well-known differences between both mid wall RVFw and mid IS wall strain when analyzing the RV; we first performed a multivariate analysis using the basal RVFw strain, then the mid RVFw strain, and finally the mid IS wall strain. As expected, TAPSE correlated well with TA TDI s’ (R2=0.9866) (Figure 1). RV mid strain (R2=0.9236) and IS mid strain (R2=0.9268) correlated better with TAPSE as compared to the correlation between RV basal-apex (R2=0.0257) and IS basal-apex (R2=0.0119) and TAPSE (Figure 2). The differences observed could be physiologically and anatomically explained based on our current understanding of RV muscle fiber arrangement and common attachment into the IS. Further research is now needed to better characterize how both RV and LV function in different clinical entities modify our interpretation of global and regional RV STs.