Abstract 15641: Quantification of Left Ventricular Shape Differentiates Pediatric Pulmonary Hypertension Patients From Matched Controls

Abstract

Background: Changes in left ventricular (LV) shape are observed in patients with pulmonary hypertension (PH). Quantification of shape changes could serve as an additional tool to non-invasively monitor pediatric patients with PH. Decomposing the shape of a ventricle into a series of components and magnitudes will facilitate differentiation of healthy and PH subjects. Methods: Parasternal short axis echo images acquired from 42 pediatric subjects with PH as well as 42 age and sex matched normal control subjects underwent speckle tracking using Velocity Vector Imaging (Siemens) to produce series of x,y coordinates tracing the LV endocardium in each frame. A Fourier transform was then used to derive shape components and magnitudes from LV shape in each frame. Magnitudes from the first 11 components were normalized to heart size (magnitude/LV length as measured on apical view) and analyzed across a single cardiac cycle. Results: Fourier decomposition produced a series of shape components from short axis echo views of the LV (Figure 1). All 11 components analyzed were significantly different between groups (Figure 2). Conclusion: Quantification of LV shape can differentiate normal pediatric subjects from those with PH. Shape analysis is a promising new method to precisely describe shape changes observed in PH. Differences between groups speak to intra ventricular coupling that occurs in right ventricular overload and may describe phenomena such as mechanical hinge points at the septal-wall interface, myocardial discontinuities or deformations from reflected pressure waves. Further analysis surrounding timing and correlation to clinical parameters is underway.