Abstract 12159: Impact of Varying Onset Timing of Diastolic Tricuspid Annular Movement and Tricuspid Inflow on Predictive Values of Doppler-derived Indices for Clinical Outcomes in Pulmonary Arterial Hypertension

Abstract

Background: In right heart failure, Doppler-derived indices such as RV performance index (RIMP) and tricuspid regurgitant duration (TRD) have been linked to clinical outcomes, but variably. We tested the hypothesis that this variability is based on varying timing and predictive value of the onset of diastolic phase, according to right atrial pressure (RAP) and to whether tissue or flow Doppler is used. Methods: We reviewed echocardiograms and catheter examinations for 151 consecutive patients with pulmonary arterial hypertension. Te’ and TE were defined as the time from QRS onset to the onset of early diastolic velocity on tissue Doppler imaging at the tricuspid valve annulus and to TRD terminal indicating the onset of tricuspid inflow. All measurements were corrected for heart rate. The patients were grouped into low (RAP < 10mmHg, n = 84) and high RAP groups (RAP ≧ 10mmHg, n = 67). Results: Over 3 years, there were 62 total deaths and 8 lung transplantations. In low RAP group, Te’ was prolonged in association with an increase in Tau (R = 0.51, p = 0.0001) and prolonged Te’ predicted higher mortality (HR = 1.20 / 10ms, p = 0.02). In high RAP group, Te’ was still prolonged as Tau increased (R = 0.43, p = 0.008) independently of RAP, while TE was reversely shortened as RAP rose (R = 0.41, p = 0.0006) and shortened TE predicted higher mortality (HR = 0.86 / 10ms, p = 0.008). An increase in RIMP using tissue Doppler only in low RAP group and shortened TRD only in high RAP group predicted higher mortality (HR = 2.09 / 0.1, p = 0.002 and HR = 0.89 / 10ms, p = 0.02, respectively), keeping in line with Te’ and TE, respectively. Conclusions: Both the onset of diastolic tricuspid annular movement and the onset of tricuspid inflow relate to relaxation disorder. As RAP elevates, only the tricuspid inflow onsets early. These observations should be considered when interpreting Doppler-derived indices: they predict clinical outcomes in a limited group of patients according to RAP and to whether tissue or flow is focused on.