Upper left: A typical color-Doppler velocity profile obtained by positioning the sample volume in the septum base. S1 = isovolumic contraction velocity in the first positive peak, PSV = peak systolic velocity. IVCT and IVRT respectively are isovolumic contraction and relaxation times, E'and A'are respectively early and late diastolic velocities. The velocity profile is accompanied by an ECG signal. Upper right. A systolic displacement image, obtained by integration of the respective velocity profile during systole that provides amplitude of total displacement (usually ≥ 12 mm in healthy individuals). Lower panel. Strain rate imaging in which the white arrow indicates peak systolic strain rate obtained by spatial differential of velocities at two points divided by the distance between them. In our laboratory the insonation distance of approximately 15 mm provides a favorable signal-to-noise ratio .