Dual pulsed-wave Doppler tracing of right ventricular inflow and outflow: single cardiac cycle right ventricular tei index and evaluation of right ventricular function.
OBJECTIVE
The reliability and usefulness of the right ventricular (RV) Tei index (RTX) remains controversial because it has not been possible to simultaneously measure RV inflow and outflow. However, dual pulsed-wave Doppler (DPD) enables flow velocities to be obtained at different sampling sites simultaneously. In this study we evaluated the feasibility and reliability of RTX values obtained by DPD (RTX(DPD)).


METHODS
Forty-one patients who underwent cardiac catheterization and echocardiography for RV volume or pressure overloading conditions were evaluated. Symptom-limited exercise treadmill testing with expired gas analysis was performed and maximal exercise capacity was measured.


RESULTS
RTX by conventional flow Doppler (RTX(CFD), 0.262±0.164) was similar to RTX(DPD) (0.253±0.117, p=NS), whereas RTX by tissue Doppler echocardiography (RTX(TDE), 0.447±0.125) was significantly larger than RTX(DPD) (p<0.001). Based on multiple regression analysis, maximal exercise capacity was independently related to RTX(DPD) (β=-0.60, p<0.001), mid-RV dimension (β=-0.26, p=0.012), left ventricular ejection fraction (β=0.22, p=0.023), and early diastolic tricuspid annular velocity (β=0.21, p=0.048).


CONCLUSIONS
It is feasible and reliable to evaluate RV function using RTX(DPD) values. However, to evaluate the clinical usefulness of RTX(DPD), additional studies are required with a large number of patients and long-term follow-up.
Choi
Jin-Oh
JO
Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Choi
Joon Hyouk
JH
Lee
Hyun Jong
HJ
Noh
Hye Jin
HJ
Huh
June
J
Kang
I Seok
IS
Lee
Heung Jae
HJ
Lee
Sang-Chol
SC
Kim
Duk Kyung
DK
Park
Seung Woo
SW