During endocardial catheter mapping, the trajectories traveled by the catheter tips are recorded for tracking the endocardial motion. The aim of this Phase I STTR application is to develop a valid four-dimensional parametric presentation of the regional left ventricular wall motion through time in cardiac cycles based on endocardial tracking. The second goal of the protocol is to apply this parametric wall motion representation to develop software modules for analyzing patterns of regional wall motions from three-dimensional reconstruction of the ventricle derived from echocardiogram or other catheter mapping data. In the Phase II of the project, the software module will be developed to apply the wall motion analysis method to contrast ventriculography, echocardiogram and magnetic resonance imaging. The proposed research will develop and validate one method and apply it to all imaging modalities.