Abstract 1967: Evaluation of Right Ventricular Function by Tricuspid Annular Plane Systolic Excursion in Tetralogy of Fallot
BACKGROUND: The accuracy of right ventricular ejection fraction (RVEF) estimation by tricuspid annular plane systolic excursion (TAPSE) by two-dimensional (2-D) echo has been repeatedly validated, but not by magnetic resonance imaging (MRI) nor in patients with congenital heart disease.
OBJECTIVE: We tested the accuracy of TAPSE in predicting RVEF in surgically repaired tetralogy of Fallot (TOF) patients from MRI.
METHODS: TAPSE was measured from systolic displacement of the RV-freewall/tricuspid annular plane junction in the apical 4-chamber view in 7 normal subjects and 14 TOF patients. The RV was reconstructed in 3-D from manually traced borders on MR images to compute true EF. Because we previously observed discrepancy between TAPSE and RVEF in the presence of regional dysfunction, we also analyzed RV wall motion in terms of regional stroke volume at 20 short axis slices from apex to tricuspid annulus.
RESULTS: RVEF was 52 ±3 in normal subjects and 41±9 in TOF (p<0.01). TAPSE correlated weakly (r=0.58, p<0.02) with RVEF (Figure 1⇓). TOF patients exhibited increased contribution to global stroke volume from apical portions of the RV and decreased contribution from the base compared to normal (p<0.05 at 13 of 20 slices, Figure 2⇓). TAPSE by MRI agreed with TAPSE by 2-D echo in 3 patients imaged by both modalities (mean difference −1±1, p=0.371).
CONCLUSION: TAPSE is not a reliable measure of RVEF in TOF. TAPSE may be of limited use in conditions that exhibit abnormal regional contraction.