Three-Dimensional Reconstruction of the Functional Strain-Line Pattern in the Left Ventricle From 3-Dimensional Echocardiography

Abstract

Advances in 3-dimensional (3D) echocardiography offer a rapid, effective imaging technique with adequate temporal and spatial resolution for left ventricular motion assessment. 3D multidirectional tracking of the endocardial left ventricular layer has shown that the functional pattern of directional strain arrangement during cardiac contraction closely relates with the structural architecture of the myocardial helical muscle fiber orientation.1 In a similar manner, we carried out segmentation tracking of the endocardial-epicardial layers in 10 healthy young athletes (nonprofessional athletes, enrolled at the Sport Medicine Center of the University of Florence, Italy, training 2–3 days a week for 2 hours daily; all exhibiting an excellent echographic window) to evaluate the 3D strain pattern over the whole myocardium thickness and to compare with the hypothesized underlying fiber architecture. An echocardiographic 3D full-volume image of the left ventricular was recorded by a Philips IE33 machine (frame rate, 15–30 Hz). Imaging data were processed by 3D feature tracking (4DLVA 3.0; TomTec Gmbh, Unterschleissheim, Germany), and the endocardial and epicardial tracked surfaces were exported for the following principal strain analysis.1 Principal strain analysis allows to define the direction along which the main contractile strain (S1) develops, accompanied by a secondary strain (S2) that is typically of much …