Accuracy of guideline recommendations for two-dimensional quantification of the right ventricle by echocardiography.

BACKGROUND: The accuracy of the guidelines of the American Society of Echocardiography (ASE) for the two-dimensional (2D) quantitative assessment of right ventricular (RV) size and function has not been evaluated against MRI-derived RV volumes in patients with congenital heart disease and RV volume overload.
METHODS: Three groups of patients were studied: a normal RV group (Group I, n = 31), a repaired tetralogy of Fallot group (Group II, n = 33), and an unrepaired atrial septal defect and/or partially anomalous pulmonary venous connection group (Group III, n = 23). Recommended 2D linear and cross-sectional area measurements were made on clinical echocardiographic and MRI studies performed less than 6 months apart.
RESULTS: Most 2D RV parameters were smaller by echocardiography versus MRI. There was weak correlation between 2D RV measurements by echocardiography and MRI-derived RV volumes (Group I: r = 0.15-0.54, Group II: r = 0.33-0.61, Group III: r = 0.32-0.85), and only modest improvement when the same 2D measurements were performed by MRI (Group I: r = 0.37-0.61, Group II: r = 0.44-0.69, Group III: r = 0.28-0.74). The difference between 2D RV measurements by echocardiography and MRI-derived RV volumes was more pronounced in the RV volume overload groups.
CONCLUSIONS: The correlation between currently recommended 2D RV measurements by echocardiography and MRI-derived RV volumes was weak, and improved only modestly when MRI was used to make the same 2D measurements. Moreover, 2D echocardiographic assessment of the RV appears to be less accurate in patients with congenital heart disease and a dilated RV.