P1389 Less dependent to loading conditions, TAPSE and S peak systolic tricuspid velocity are the 2 most robust indices to investigate right ventricular systolic function

Abstract Background The daily challenge in pulmonary hypertension (PH) is to utilize a non-invasive echocardiographic parameter that is less load-dependent to follow-up right ventricular (RV) systolic function. VMAX, also called the maximum no-load contractile element velocity is known to be a strong load-independent contractility parameter, as good as the end-systolic pressure volume relationship that is simply obtained from pressure tracing. Purpose We aimed to investigate which among the 6 most common RV systolic function echocardiographic indices are less load-dependent by comparing them to VMAX. Population Sixteen patients scheduled for suspected or established PH had right-heart catheterization and ultrasound study the same day. Tricuspid annular plane systolic excursion (TAPSE), peak S tricuspid annulus velocity, both RV free wall and septal 2D strain, RV TEI index, tricuspid regurgitation - dP/dt and RV fractional area change were acquired from standardized echocardiographic protocol. The PressureWire Certus (Saint Jude Medical, Minnesota, USA) used to monitor invasive RV pressure is a 0.014" wire with high-fidelity sensor technology, operating with a frequency response of 0 to 25 Hz and exhibiting an accuracy of ± 1 mm Hg. A dedicated software was used to display simultaneously RV pressure and dP/dt and tracings where stored for offline analysis. VMAX was the y-axis intercept obtained by fitting a straight line through multiple points on the stress and pressure derivative curves by a least squares technique during isovolumic contraction. Results VMAX averaged 2.1 ± 0.9 length/s (range 0.80 to 4.43 length/s). The relationship is acceptable for the 2D strain (y = 0.08 x + 0.89, r = 0.53, p = 0.038) compared with VMAX, is improved between TAPSE and VMAX (y = 1.19x + 0.03, r = 0.76, p < 0.0001) but is best between peak S tricuspid annulus velocity and VMAX (y = 0.26 x – 0.60, r = 0.90, p < 0.0001). The TEI index, non-invasive dP/dt and right ventricular fractional area change did not correlate with VMAX. (FIG 1) Conclusion Both TAPSE and S peak systolic velocity are good markers of RV contractility with relatively load-independency in the setting of pulmonary hypertension. Abstract P1389 Figure.