Functional assessment of the dynamic profile of tricuspid annular motion

Background: Maximal systolic tricuspid annulus (TA) descent by M-mode (MM) is a well described and accepted standard reference of right ventricular (RV) systolic function; however, the contribution of each individual TA contour during the cardiac cycle has not been well characterized. Therefore, the aim of this study was to define each peak and nadir component of the constantly moving annulus. Material and Methods: Standard echocardiographic data was collected from 35 patients over a wide range of both normal and abnormal RV systolic function. Time to onset and total duration of each recognizable component of the TA tissue Doppler imaging (TDI) signal was measured and correlated to each individual change in contour of the TA, obtained by MM, during the cardiac cycle. Results: In this heterogeneous patient population, careful measurement of each recognizable component of the TA TDI signal corresponded to conformational changes in the TA contour. Furthermore, these TA TDI intervals were imprinted into the TA MM tracing and precisely identified specific systolic as well as diastolic events, regardless of RV systolic function or pulmonary hypertension severity. Conclusions: Careful observation of the constant dynamic motion of the TA, aided by high temporal resolution MM, allows better understanding of each individual component of annular motion. It appears that each peak and nadir component not only is useful in characterizing RV systole and diastole, but also would be invaluable to assess the functional relationship that exists between the right atria and ventricle; particularly, when annular motion directly reflects the contribution of both cardiac chambers