An Effective 3-Dimensional Regional Myocardial Strain Computation Method with Displacement ENcoding with Stimulated Echoes (DENSE) in Dilated Cardiomyopathy Patients and Healthy Subjects

Fast Cine Displacement ENcoding with Stimulated Echoes (DENSE) is a magnetic resonance imaging (MRI) technique attributed with higher spatial resolution and rapid post-processing. Our primary goal was three-dimensional (3D) regional strains quantification using DENSE images in healthy subjects and non-ischemic, non-valvular dilated cardiomyopathy (DCM) patients, followed by validation with comparison to a standard established sequence. Cine DENSE data were acquired using an echo planar imaging (EPI) sequence. A meshfree multiquadrics radial point interpolation method (RPIM) was used for computing Lagrange strains in sixteen left ventricular segments. Validation of 3D regional strains computed with DENSE was conducted in reference to standard tagged MRI via Bland-Altman analyses. Additionally, repeatability studies in DENSE were conducted with healthy subjects and Bland-Altman analysis between repeated measures conducted to increase confidence in DENSE. Welch-Satterthwaite t-tests were used to estimate differences in DENSE generated regional strains between DCM and healthy subjects. Computed regional circumferential strain differences were 0.01 ± 0.03 (95% limits of agreement) from the DENSE-tagged MRI comparison in healthy subjects, 0.01 ± 0.05 from the DENSE-tagged MRI comparison in DCM patients, 0.0 ± 0.02 from repeatability studies and similar agreements were found in longitudinal and radial strains. Good regional strain agreements between modalities and in repeatability studies validated high resolution DENSE as a reliable modality for estimating 3D strains in cardiovascular biomechanics.