MRI Study of Strain Feature of Left Ventricular Long-axis Myocardium in Normal Young Adults / 中国医学影像学杂志

ABSTRACT

Purpose To measure the longitudinal and transverse strain and displacement parameters of each segment of long axis myocardium on cardiac MRI film images of normal young volunteers using feature tracking technique (FT), and to analyze the regularity of left ventricular long axis strain and establish peak and time to peak (TTP) reference range concerning the longitudinal and transverse strain and displacement. Materials and Methods Cardiac film images of 29 healthy volunteers aged 24 to 34 were collected using Philips Multiva 1.5T MRI scanner, including three typical long axis planes of the left ventricular long axis, left ventricular outflow tract, and four-chamber view. The MRI film images were analyzed drawing on myocardial feature tracking software TOMTEC, and the peak value and TTP of longitudinal and transverse strain and displacement of the 16 AHA segments excluding apex cordis were obtained thereby. The regularity of each parameter concerning the plane, layer, and segment was summarized and analyzed. Results The TTP of longitudinal strain, longitudinal displacement and transverse strain were consistent among each myocardial segment, which was a constant indicator in (41.24±12.51) ％ RR interphase. The peak value of longitudinal displacement was represented by apex cordis (2.56±0.89) mm < middle (6.09±2.03) mm < cardiac base (8.07±2.05) mm, and the peak value of transverse displacement was manifested as apex cordis (4.57±1.18) mm < middle (5.65±0.84) mm < cardiac base (8.48 ±1.18) mm, which was consistent with cardiac geometric deformation visually observed. The longitudinal strain showed consistency on 2CH-3CH-4CH plane, whose peak reference value was (-22.46±13.19)％; while the peak value of transverse strain displayed no consistency on different planes. Conclusion The longitudinal strain of the left ventricular on different planes has consistent peak value and TTP, suggesting good reference value.