Comparison of 3D echocardiography-derived stroke volume ratio with VTI method: A correlation study

Introduction

Quantification of the pulmonary-to-systemic flow ratio (Qp:Qs) or stroke volume is important in assessing cardiac shunts or regurgitations. While the echocardiography velocity time integral (VTI) method is routinely used, 3D echocardiography offers another non-invasive alternative.

Objective

This study aims to correlate stroke volume ratios derived from 3D echocardiography with those obtained by conventional method.

Methods

We prospectively included patients with various cardiac conditions and without systemic valve stenosis or atrioventricular regurgitation who underwent conventional echocardiography with 3D acquisitions (4D auto RVQ and LVQ, GE Healthcare) for ratio assessment.

Results

Thirty-five patients with a mean age of 7.9 years old (range: 1.1–16.9) were included, 16 patients with shunt and 19 normal patients. The correlation coefficient between stroke volume ratios obtained by 3D echocardiography and VTI method was 0.876 (P < 0.001). The 3D Qp:Qs was closer to 1 in structurally normal hearts [0.99 ± 0.04] than with the VTI method [1.08 ± 0.23].

Conclusion

3D echocardiography demonstrates good correlation with VTI method in assessing stroke volume ratios, supporting its utility for evaluating cardiac shunts in situations where VTI calculation is not feasible or reliable (like shunts with pulmonary stenosis). Further studies are warranted to validate its use, particularly in comparison with Qp:Qs ratios derived from cardiac magnetic resonance imaging (MRI) and to explore its broader clinical applications.