Does an accelerated 3D LGE pulse sequence improve image quality and reduce imaging time compared to a reference sequence for detecting atrial scar and fibrosis in patients with atrial fibrillation?
An accelerated 3D LGE MRI sequence significantly reduced imaging time and improved image quality for detecting left atrial scar and fibrosis in patients with atrial fibrillation compared to a standard reference sequence.
Purpose To develop an accelerated three-dimensional (3D) late gadolinium enhancement (LGE) pulse sequence using balanced steady-state free precession readout with stack-of-stars k-space sampling and extra motion-state golden-angle radial sparse parallel (XD-GRASP) reconstruction and test the performance for detecting atrial scar and fibrosis in patients with atrial fibrillation (AF). Materials and Methods Twenty-five patients with AF (20 paroxysmal and five persistent; 65 years ± 7 standard deviation; 18 men) were imaged at 1.5 T using the proposed LGE sequence with 1.3 mm × 1.3 mm × 2-mm spatial resolution and predictable imaging time. The resulting images were compared with historic images of 25 patients with AF (18 paroxysmal and seven persistent; 67 years ± 10; 14 men) obtained using a reference 3D left atrial (LA) LGE sequence with 1.3 mm × 1.3 mm × 2.5-mm spatial resolution. Two readers visually graded the 3D LGE images (conspicuity, artifact, noise) on a five-point Likert scale (1 = worst, 3 = acceptable, 5 = best), in which the summed visual score (SVS) of 9 or greater was defined as clinically acceptable. Appropriate statistical analyses (Cohen κ coefficient, Mann-Whitney U test, t tests, and intraclass correlation) were performed, where a P value < .05 was considered significant. Results Mean imaging time was significantly shorter (P < .01) for the proposed pulse sequence (5.9 minutes ± 1.3) than for the reference pulse sequence (10.6 minutes ± 2). Median SVS was significantly higher (P < .01) for the proposed (SVS = 11) than reference (SVS = 9.5) 3D LA LGE images. Interrater reproducibility in visual scores was higher for the proposed (κ = 0.78–1) than reference 3D LA LGE (κ = 0.44–0.75). Intrareader repeatability in fibrosis quantification was higher for the reference cohort (intraclass correlation coefficient ICC = 0.94) than the prospective cohort (ICC = 0.79). Conclusion The proposed 3D LA LGE method produced clinically acceptable image quality with 1.5 mm × 1.5 mm × 2-mm nominal spatial resolution and 6-minute predictable imaging time for quantification of LA scar and fibrosis in patients with AF. Supplemental material is available for this article. Keywords: Adults, Cardiac, Left Atrium, MR-Imaging, Pulmonary Vein Isolation or Ablation (PVI), Technology Assessment © RSNA, 2020
Gunasekaran et al. (Thu,) studied this question.