Takahama, Hiroko

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.

Background: Increased reflective wave from pulmonary artery (PA) causes mid-systolic deceleration (MSD) and notching in Doppler flow velocity envelope of RV ejection flow. Our aim is to test whether profile of MSD and notching provides insight into hemodynamics and patient outcomes in pulmonary artery hypertension (PAH), using quantitative measurements. We hypothesized that the deceleration time of the MSD slope (DTMSD), meaning the steepness of the slope, reflects interaction between RV ejection and reflective wave, and that peak velocity of post-notching flow (Vpost) reflects RV function. Methods: We reviewed RV ejection flow envelope recordings by pulsed wave Doppler for 157 consecutive patients with PAH between 1/2008 and 3/2013 (age 57 ± 14) with an estimated RV systolic pressure of 79 ± 23 mmHg. DTMSD was measured as the time between the first peak acceleration wave and MSD slope extrapolated to zero line. We also reviewed right heart catheterization performed within one month from echocardiography in 78 of the 157 patients. Results: We identified MSD and notching in 148 patients. On multivariate regression analyses, PA capacitance was the key determinant of DTMSD (beta = -0.49, p <0.0001). Vpost was determined by cardiac index (beta = -0.36, p = 0.0014). During a median follow-up period of 30 months, there were 47 deaths from all causes and 7 lung transplantations. On Cox hazard analyses, shorter DTMSD and smaller Vpost are significant predictors of higher mortality independently of each other (HR 0.92 / 10ms, p = 0.045 and HR 0.97, p = 0.028, respectively). Conclusion: Mid-systolic deceleration of RV ejection flow became steeper in the setting of lower PA compliance causing a greater reflectance wave. Reduced peak velocity of post-notching flow reflected impaired RV with reduced cardiac output. Quantitative assessment of profile of mid-systolic deceleration and notching in RV ejection flow envelope is useful in predicting hemodynamics and patient outcomes in PAH.