The role of echocardiography for quantitative assessment of right ventricular size and function in adults with repaired tetralogy of Fallot

Background: Quantitative assessment of right ventricular (RV) systolic function by echocardiography is challenging in patients with congenital heart disease because of the complex geometry of the RV and the iatrogenic structural abnormalities resulting from prior cardiac surgeries. The purpose of this study was to determine the correlation between echocardiographic indices of RV systolic function and cardiac magnetic resonance imaging (CMRI) derived RV ejection fraction (RVEF) in adults with repaired tetralogy of Fallot (TOF). Methods: Quantitative assessment of RV function was performed with RV tissue Doppler systolic velocity (RV s'), tricuspid annular plane systolic excursion (TAPSE), and fractional area change (FAC). These echocardiographic indices were compared to RVEF from CMRI performed on the same day as echocardiogram. Results: Of 209 patients, the mean RV FAC was 39 ± 9%, TAPSE was 18 ± 4 mm, RV s' was 10 ± 2 cm/s, and RVEF was 40 ± 10%. There was a good correlation between TAPSE and RVEF (r = 0.79, P <.001), good correlation between RV s' and RVEF (r = 0.71, P <.001), and modest correlation between FAC and RVEF (r = 0.66, P <.001). TAPSE < 17 mm effectively discriminated between patients with RV systolic dysfunction defined as RVEF < 47% (sensitivity 81%, specificity 79%, area under the curve [AUC] 0.805). FAC < 40% was associated with RVEF < 47% (sensitivity 72%, specificity 63%, AUC 0.719). RV s' < 11 cm was associated with RVEF < 47% (sensitivity 83%, specificity 68%, AUC 0.798). Conclusion: Despite the structural and functional abnormalities of the RV in patients with repaired TOF, quantitative assessment of RV systolic function by echocardiography is feasible and had good correlation with CMRI-derived RVEF.