Wideband arrhythmia‐Insensitive‐rapid (AIR) pulse sequence for cardiac T1 mapping without image artifacts induced by an implantable‐cardioverter‐defibrillator

PURPOSE: To develop and evaluate a wideband arrhythmia-insensitive-rapid (AIR) pulse sequence for cardiac T1 mapping without image artifacts induced by implantable-cardioverter-defibrillator (ICD). METHODS: We developed a wideband AIR pulse sequence by incorporating a saturation pulse with wide frequency bandwidth (8.9 kHz) to achieve uniform T1 weighting in the heart with ICD. We tested the performance of original and "wideband" AIR cardiac T1 mapping pulse sequences in phantom and human experiments at 1.5 Tesla. RESULTS: In five phantoms representing native myocardium and blood and postcontrast blood/tissue T1 values, compared with the control T1 values measured with an inversion-recovery pulse sequence without ICD, T1 values measured with original AIR with ICD were considerably lower (absolute percent error > 29%), whereas T1 values measured with wideband AIR with ICD were similar (absolute percent error < 5%). Similarly, in 11 human subjects, compared with the control T1 values measured with original AIR without ICD, T1 measured with original AIR with ICD was significantly lower (absolute percent error > 10.1%), whereas T1 measured with wideband AIR with ICD was similar (absolute percent error < 2.0%). CONCLUSION: This study demonstrates the feasibility of a wideband pulse sequence for cardiac T1 mapping without significant image artifacts induced by ICD.