Assessment of regional and global right ventricular systolic function in children with repaired tetralogy of Fallot.

BACKGROUND

Echo assessment of right ventricular function is difficult due to its complex geometry and regional differences in wall motion. In patients with repaired tetralogy of Fallot, cardiac MRI is the gold standard for assessment of right ventricular function. There is scant data regarding the correlation of echo measures of right ventricular function with cardiac MRI right ventricular function in the paediatric population.

METHODS

Echocardiographic measures of regional and global right ventricular function were reviewed in 56 patients with repaired tetralogy of Fallot and 27 patients with structurally normal hearts. These measures were compared to global right ventricular ejection fraction by cardiac MRI.

RESULTS

Despite having the same right ventricular ejection fraction by cardiac MRI as normal controls, patients with repaired tetralogy of Fallot had significantly worse global and regional echocardiographic measures of right ventricular function. Right ventricular fractional area change and fractional shortening of the right ventricular outflow tract correlated best with global right ventricular function by MRI. Incorporation of these measures into a regression model allowed accurate prediction of global right ventricular function by cardiac MRI.

CONCLUSION

Children with repaired tetralogy of Fallot have abnormal regional and global right ventricular function compared to patients with normal hearts. Despite the presence of patch material, the right ventricular outflow tract significantly contributes to global right ventricular function by cardiac MRI. When incorporated into a model that includes regional and global echocardiographic measures of right ventricular function, right ventricular outflow tract fractional shortening helps predict global right ventricular function by MRI.