Cardiac phase-resolved late gadolinium enhancement imaging

Abstract

Late gadolinium enhancement (LGE) with cardiac magnetic resonance (CMR) imaging is the clinical reference for assessment of myocardial scar and focal fibrosis. However, current LGE techniques are confined to imaging of a single cardiac phase, which hampers assessment of scar motility and does not allow cross-comparison between multiple phases. In this work, we investigate a three step approach to obtain cardiac phase-resolved LGE images: (1) Acquisition of cardiac phase-resolved imaging data with varying T1 weighting. (2) Generation of semi-quantitative T1* maps for each cardiac phase. (3) Synthetization of LGE contrast to obtain functional LGE images. The proposed method is evaluated in phantom imaging, six healthy subjects at 3T and 20 patients at 1.5T. Phantom imaging at 3T demonstrates consistent contrast throughout the cardiac cycle with a coefficient of variation of 2.55 ± 0.42%. In-vivo results show reliable LGE contrast with thorough suppression of the myocardial tissue is healthy subjects. The contrast between blood and myocardium showed moderate variation throughout the cardiac cycle in healthy subjects (coefficient of variation 18.2 ± 3.51%). Images were acquired at 40–60 ms and 80 ms temporal resolution, at 3T and 1.5, respectively. Functional LGE images acquired in patients with myocardial scar visualized scar tissue throughout the cardiac cycle, albeit at noticeably lower imaging resolution and noise resilience than the reference technique. The proposed technique bears the promise of integrating the advantages of phase-resolved CMR with LGE imaging, but further improvements in the acquisition quality are warranted for clinical use.

Free-running cardiac magnetic resonance fingerprinting: Joint T1/T2 map and Cine imaging

“…In this study free-running cardiac MRF was performed without contrast injection. Post contrast injection applications could potentially offer shorter acquisition times due to shorter relaxation times, additional extra cellular volume (ECV) information and synthetic late gadolinium enhanced contrasts [47,48] different cardiac phases could be obtained. Such an acquisition providing tissue characterisation and function with whole heart coverage could greatly simplify the workflow of CMR exams [44] by providing comprehensive assessment of cardiac health in one acquisition potentially acquired twice (pre and post contrast).…”

Motion-compensated T1 mapping in cardiovascular magnetic resonance imaging: a technical review

“…The last RR interval where the signal has mostly recovered was used to determine displacement fields between cardiac phases, which were propagated to other RR intervals and high-resolution averaged acquisitions to generate a cine series at every TI and for the map. Recently, Weingärtner et al proposed a method to generate cardiac-resolved LGE imaging that made use of multiple images at each cardiac phase to generate auxiliary cardiac-resolved maps and images ( 56 ). These images were used to create synthetic LGE images at each cardiac phase to jointly visualize cardiac function and cardiac fibrosis.…”

Free‐running 3D whole‐heart T1 and T2 mapping and cine MRI using low‐rank reconstruction with non‐rigid cardiac motion correction

“…Additionally, while the results are pre-contrast, the framework also has the potential to be applied post-contrast and used in the generation of synthetic LGE images. [56][57][58] A limitation of the proposed framework is the current long computational time. Using 30% of the acquired data, the LRI+HD-PROST reconstruction at all 16 cardiac phases took ∼8 h, with an additional ∼2 h required for the LRMC+HD-PROST reconstruction of each cardiac phase.…”