Changes in left ventricular shape and morphology in the presence of heart failure: a four-dimensional quantitative and qualitative analysis.

Abstract

The presence and progression of heart failure (HF) are associated with cardiac remodelling, defined as cellular, molecular and interstitial changes which occur after injury and manifest as changes in left ventricular (LV) size, mass, geometry and function. This research study was designed to investigate the changes to LV morphology and shape which occur in the presence of heart failure using three-dimensional (3D) modelling and analysis of cardiac-gated CT scans from both healthy individuals and patients classified with HF. A number of quantitative and qualitative strategies were applied to cardiac CT scans of HF patients and healthy controls (n = 7) in order to analyse changes to LV size, shape and structure and to examine LV remodelling in the different classes of HF. Three-dimensional wireframe representations of endocardial and epicardial borders were created, three-dimensional computer stereolithography models of the inner LV cavity and myocardial wall segments were generated and three-dimensionally printed and a number of clinical LV dimension and shape indices were measured. All data were analysed using one-way ANOVA with post hoc Tukey method for multiple comparisons for significant variables. Results of most significance included abnormalities in LV mass and end-systolic dimensions and significantly increased septal wall thickness among mid-range ejection fraction cases. Also of importance were significant increases in both dimension-based and volumetric sphericity index measures in all HF cases. Three-dimensional printed models provided qualitative information as to changes in inner LV cavity and myocardial wall morphology across the cardiac cycle for healthy and HF cases and validated quantitative findings. Findings from this study can successfully be applied to motivate the research and development of new HF treatment strategies and devices as well as for the development of a realistic cardiac simulator system.