INTRODUCTION
Accurate and reproducible measurements of cardiac chambers are a vital component of diagnosis, prognostication, medical management, and surgical referral in congenital as well as acquired heart diseases in children1, 2,3,4,5. Three-dimensional volumetric echocardiography (3DE) is an emerging alternative to two-dimensional echocardiography (2DE) which makes fewer geometric assumptions regarding chamber shapes and may provide benefits in accuracy and reproducibility compared to 2DE6,7,8.
It is therefore important to establish that commercially available algorithms for 3D measurement of cardiac chambers produce comparable results. Both TomTec 4D LV-Analysis software and Philips QLAB LV 3D underestimate LV volumes compared to MRI and have relatively wide inter-vendor limits of agreement in neonates and infants9. Although left atrial (LA) 3DE volumetric analysis packages exist, most studies have used LV packages6,7.
Knowledge-based reconstruction (KBR) is an alternative volumetric methodology whereby 2DE images tracked in 3D space via a magnetic localizer are reconstructed into a 3D dataset from which volumes can be measured, thus overcoming the temporal and spatial resolution issues of 3DE. Ventripoint Medical Systems (VMS+ 3.0, (Ventripoint Diagnostics Ltd., Toronto ON), utilizes a piecewise smooth subdivision surface algorithm and an MRI-derived catalogue of heart datasets to reconstruct a unique cardiac chamber rendering for each patient. VMS software includes specific algorithms for all four cardiac chambers and has been previously validated for right and left ventricular volume measurements10,11,12. 3DE data and 3D MRI datasets can also be imported into VMS3.0 for analysis, however no validation of the resultant chamber volumes has been made against other 3DE analysis software.
This study aimed to compare 3DE dataset derived LA and LV volumetric measurement using VMS3.0 and TomTec 4D LV-analysis software. We hypothesized that VMS would offer an alternative volumetric measurement technique for cardiac chambers using a semi-automated software algorithm with results comparable to TomTec.