ORIGINAL ARTICLE Ventricular Function Three-Dimensional Myocardial Strains at End-Systole and During Diastole in the Left Ventricle of Normal Humans

This paper presents the three-dimensional strains in the normal human left ventricle (LV) at end-systole and during diastole. Magnetic resonance tissue tagging was used to measure strain in the left-ventricular heart wall in 10 healthy volunteers aged between 28 and 61 years. The three-dimensional motion was calculated from the displacement of marker points in short- and long-axis cine images, with a time resolution of 30 msec. Homogeneous strain analysis of small tetrahedrons was used to calculate deformation in 18 regions of the LV over a time span of 300 msec starting at end systole. End-systolic radial strain was largest near the heart base, and circumferential and longitudinal strains were largest near the apex. During diastole, the circumferential–longitudinal shear strain (associated with LV torsion) was found to recover earlier than the axial strains. Assessment of three-dimensional diastolic strain is possible with MR tagging. Comparison of patient strain against normal strain may permit early detection of regional diastolic dysfunction