Comparison of ECV measurements during equilibrium between IR- and SR-based Cardiac T1Mapping

Background Cardiac T1 and extracellular volume fraction (ECV), derived from preand post-contrast cardiac and blood T1 measurements, are emerging imaging biomarkers of diffuse cardiac fibrosis. The most frequently used cardiac T1 mapping pulse sequence is MOLLI [1]. However, MOLLI is known to be sensitive to rapid heart rate and irregular rhythm, because it is based on inversion-recovery (IR) of magnetization preparation. In response, we developed an arrhythmia-insensitive-rapid (AIR) cardiac T1 mapping pulse sequence based on B1insensitive saturation-recovery (SR) of magnetization preparation [2]. Our prior study [2] showed that AIR (scan time = 2-3 heart beats) is faster and yields more accurate cardiac T1 measurements than MOLLI (scan time = 17 heart beats). We sought to compare ECV measurements between SR-based AIR and IR-based MOLLI cardiac T1 mapping at 3T.