Accurate and robust systolic myocardial T1 mapping using saturation recovery with individualized delay time: comparison with diastolic T1 mapping

T 1 mapping data are generally acquired in patients’ diastolic phase, wherein their myocardium is the thinnest in the cardiac cycle. However, the analysis of the thin myocardium may cause errors in image registrations and settings related to the region of interest. In this study, we validated systolic T 1 mapping using the saturation recovery with individualized delay time (SR-IDT) method and compared it with conventional diastolic T 1 mapping. Both diastolic and systolic T 1 mappings were performed in the mid-ventricular plane in 10 healthy volunteers (35 ± 9 years, 9 males) and 29 consecutive patients with cardiac diseases (68 ± 14 years, 19 males). Comparison of the myocardial T 1 value at diastole and systole was performed with both the Pearson correlation coefficient ( r ) and the Bland–Altman analysis. Additionally, the systolic myocardial T 1 value was compared between the volunteers and patients by using Tukey’s test. Pearson correlation analysis demonstrated a strong positive correlation between diastolic and systolic T 1 values ( r = 0.88, P