Abstract 1775: 3-D Echocardiographic Assessment of Right Ventricular Volume and Function in Adult Patients With Congenital Heart Disease: Comparison With Magnetic Resonance Imaging
Background Literature addressing the feasibility of 3D ultrasound (US) in the assessment of the right ventricle (RV) in adults with complex congenital heart disease is sparse although important as it has implications in timing of surgery. We evaluated this modality in adult patients with complex RV geometry due to severe pulmonary regurgitation secondary to previous Tetralogy of Fallot repair.
Methods Twenty five patients referred for cardiac MRI RV assessment also underwent 3D US. The full volume 3D RV US data sets were analyzed with 4-dimensional analysis software (TomTec Imaging Systems, Munich, Germany) and data compared with that derived by cardiac MRI (standard method).
Results The RV ejection fraction was 42 ±8% with 3D US and 44 ±7% with MRI (r=0.89, p<0.0001). The end-diastolic volume (EDV) measurements were 249 ± 66 ml and 274 ± 82 ml, and endsystolic volume (ESV) measurements 147 ± 50 ml and 159 ± 60 ml by 3D US and MRI, respectively. Similarly, there was a strong correlation of both EDV and ESV measurements by 3D US and MRI (r=0.88, p<0.0001 and r=0.89, p<0.0001 respectively). 3D US underestimated both EDV and ESV by 9% compared to MRI. Correlation and agreement of EDV between 3D US and MRI improved in the subgroup of patients (n=10) with RV EDV < 250 ml; r=0.92, p=0.0001. 3D US underestimated EDV by 3% in this subgroup.
Conclusions In complex patients with Tetralogy of Fallot and severe pulmonary regurgitation, 3D US was feasible in quantifying RV size and function despite abnormal RV remodeling and severe enlargement that occurs in this population. As technology evolves to improve imaging of the larger pathologic RV, volume underestimation by 3D US will become less of an issue making it an important modality in complex congenital heart disease.