Doppler tissue imaging evaluation of right ventricular function at rest and during dobutamine infusion in patients after repair of tetralogy of Fallot.

BACKGROUND

Reliable, non-invasive evaluation of right ventricular function, especially in congenital heart disease, is challenging.

OBJECTIVES

The aim of this study was to evaluate Doppler tissue imaging (DTI) parameters of lateral tricuspid annular motion, mean rate of pressure rise during RV contraction (mean dP/dt) and indexed right ventricular (RV) stroke volume (RVSVi) as RV function indices in repaired tetralogy of Fallot (TOF).

METHODS

DTI evaluation was performed in 25 repaired-TOF patients, aged 11+/-6, at rest and during dobutamine infusion and 20 controls at rest.

RESULTS

TOF patients had lower (P<0.05) peak systolic velocity (Sa) (11.4+/-4 vs. 13.7+/-3.1 cm/s), early diastolic velocity (Ea) (11+/-3.1 vs. 16.3+/-3.5 cm/s) and Sa/time from onset of QRS to Sa (Sa/Q-Sa) (68.8+/-26.4 vs. 92.3+/-29.4 cm/s2) versus controls. Dobutamine increased (P<0.01) Sa (11.4+/-2.8-17.7+/-4.7 cm/s), Ea (11+/-3.1-15.6+/-3.9 cm/s), late diastolic velocity (Aa) (8.4+/-2-14.8+/-5 cm/s), Sa/Q-Sa (68.8+/-26.4-17 6.8+/-84.5 cm/s2), mean dP/dt (180+/-74-537+/-37 2 mmHg/s), and RVSVi (7.8+/-3.9-11.9+/-5.6 L/min/m2). RVSVi increase correlated (P<0.01) with that in Sa (r=0.6), Ea (r=0.5), Sa/Q-Sa (r=0.71), and mean dP/dt (r=0.57) while mean dP/dt increase correlated strongly with Sa/Q-Sa increase (r=0.88).

CONCLUSION

DTI evaluation of tricuspid annular motion during dobutamine infusion in repaired TOF correlates with dP/dt and RV stroke volume and may help in assessing RV function and reserve.