Three dimensional (3D) Ultrasound imaging provides the most accurate measurement of the volume of the heart’s left ventricle. We have developed methods for acquiring and quantitatively analyzing 3D echocardiograms to measure the size, shape, adjunction not only of the left ventricle but also the mitral apparatus and other structures in the mitral apparatus. Threse methods provide a powerful tool to investigate structure-function relationships, evaluute surgical procedures, and assess Patient prognosis.