Artifacts at Cardiac MRI: Imaging Appearances and Solutions.

Cardiac MRI (CMR) is an important imaging modality in the evaluation of cardiovascular diseases. CMR image acquisition is technically challenging, which in some circumstances is associated with artifacts, both general as well as sequence specific. Recognizing imaging artifacts, understanding their causes, and applying effective approaches for artifact mitigation are critical for successful CMR. Balanced steady-state free precession (bSSFP), the most common CMR sequence, is associated with band and flow artifacts, which are amplified at 3-T imaging. This can be mitigated by targeted shimming, by short repetition time, or by using a frequency-scout sequence. In patients with cardiac arrhythmias or poor breath hold, the quality of cine imaging can be improved with a non-electrocardiographically gated free-breathing real-time sequence. Motion artifacts on late gadolinium enhancement (LGE) images can be mitigated by using single-shot technique with motion compensation and signal averaging. LGE images are also prone to partial-volume averaging and incomplete myocardial nulling. In phase-contrast imaging, aliasing artifact is seen when the velocity of blood is higher than the encoded velocity. Aliasing can be mitigated by increasing the encoded velocity or using postprocessing software. In first-pass perfusion imaging, a dark rim artifact due to Gibbs ringing can be distinguished from a true perfusion defect based on earlier appearance and fading after a few cardiac cycles. With implanted cardiac devices, artifactual high signal intensity mimicking scar is seen on LGE images, which can be mitigated using a wide-band sequence. With devices and metallic artifacts, traditional gradient-recalled echo sequence has fewer artifacts than bSSFP. CMR at 3 T requires adaptation of sequences to minimize artifacts. RSNA, 2025