3D echocardiographic analysis of segmental left ventricular volume change. A and B. A represents data from a healthy subject and B represents data from AL subject. Top panel shows 16 segments analyzed (excludes apex) with solid cast representing endsystolic volume and surrounding grid cast representing beginning systole (or end-diastole) volume. The bottom panel shows the regional volume expressed in proportion to end-diastolic volume with time during the cardiac cycle. In these 2 examples, the dispersion of timing of endsystole is narrower in A compared to B.