Fig. 1

Schematic illustration of the marker array of the tricuspid valve complex (a): ten spherical markers were sewn to the tricuspid annulus (dark grey circles, #1–10), one marker was sewn to the anterior leaflet (light grey circle, #11), nine markers were sewn to the epicardial surface of the right ventricle (black circles, on a basal, equatorial and apical level) and three markers were implanted into the interventricular septum (open circles). To gain insight into regional tricuspid annular excursion, the distances between the left ventricular apex marker and all ten tricuspid annular markers were calculated and plotted throughout the cardiac cycle (b). Tricuspid annular and right ventricular septal-lateral/TA-SL and RV-SL, respectively) motion was quantified by calculating the distance between the respective marker pairs (blue TA-SL, red RV-SL). Posterior leaflet motion was determined as changes of the angle α11 (formed by a line through the tricuspid annulus and a line though the tricuspid annulus and posterior leaflet marker (green, c). Regional RV contraction was quantified by calculating the triangular areas formed by the respective marker triplets derived from the markers on the RV epicardial surface (d, triangles 1–7). APCOM, SPCOM and SACOM = anterior–posterior, septal–posterior and septal–anterior commissure, respectively, ANT, POS, and SEP anterior, posterior and septal tricuspid leaflet, PA pulmonary artery, LV left ventricle