True relationship between tricuspid annular motion and velocity displacement components: Potential role in assessing right ventricular decoupling

BACKGROUND: Although measures of longitudinal displacement of the tricuspid annulus measured by M-mode as tricuspid annular systolic plane excursion (TAPSE) and systolic velocity by tissue Doppler imaging (TA TDI s) are routinely used for assessment of right ventricular (RV) systolic function; these measures describe different phenomena and should not be used interchangeably. METHODS: Previously published data was used to determine the individual relationship between TAPSE and TA TDI s with increasing pulmonary artery systolic pressures (PASP). RESULTS: In this retrospective analysis, 488 patients were divided into 2 groups based on TAPSE (Group 1: <1.8 cm and Group 2: ≥1.8 cm). A robust correlation (R = .79) between TAPSE and TA TDI s noted for the entire population. However, a statistically lower correlation (R = .43) was seen between Group 1 and Group 2 (R = .65; p < .0047). With increasing pulmonary pressures, only PASP (p < .0001) and TA TDI s (p < .0001) discriminated between low and normal TAPSE/PASP values. Suggesting that a TA TDI s/PASP ratio would be most useful than TAPSE/PASP with a specificity of 80%. CONCLUSIONS: Significant differences exist between TAPSE and TA TDI s, particularly at low TAPSE values with increased PASP, were uncoupling occurs. Our data seems to suggest that TA TDI s/PASP would be most useful than TAPSE/PASP ratio. Future studies should address, if abnormalities in the material properties along the RV free wall account for these differences seen between TAPSE and TA TDI s.