The 3D ultrasound imagery becomesmore and more attractive for cardiac studies due to its simplicity, its improved reproducibility, and better precision, as compared to standard 2D echographic exams. However, automatic tools are needed to fully and efficiently analyze the large amounts of data obtained. In this paper, we present an automatic tool, aimed at the quantitative analysis of heart motion, based on the segmentation of the endo-cardium of the left ventricle. Using our method, quantitative measurements on volumes such as stroke and ejection-fraction (EF) are readily available (without needing any geometrical assumption), as well as regional wall motion parameters.