A fast navigator-gated 3D sequence for delayed enhancement MRI of the myocardium: comparison with breathhold 2D imaging.

PURPOSE: To develop a rapid navigator-gated three-dimensional (3DNAV) delayed-enhancement MRI (DE-MRI) sequence for myocardial viability assessment, and to evaluate its performance with breathhold two-dimensional (2DBH) DE-MRI sequence as the reference standard.
MATERIALS AND METHODS: 2DBH DE-MRI was initiated 10 minutes after contrast administration and followed by 3DNAV DE-MRI in 23 patients at 1.5 T. Comparison was performed using three qualitative criteria (image quality score, diagnostic outcome, relative diagnostic confidence score) in all patients, and three quantitative criteria (infarct volume, infarct signal-to-noise ratio [SNR(inf)], and infarct-viable myocardium contrast-to-noise ratio [CNR(inf-myo)]) in patients with hyperenhanced myocardium.
RESULTS: Compared to 2DBH DE-MRI, 3DNAV DE-MRI provided slightly better image quality, the same final diagnostic outcomes, and better relative diagnostic confidence score with 79% SNR(inf) improvement (P = 0.002) and 90% CNR(inf-myo) improvement (P = 0.004) in 39% less scan time (414 +/- 118 seconds for 2DBH and 251 +/- 93 seconds for 3DNAV). The measured infarct volumes demonstrated excellent correlation (18.9 +/- 19.0 mL for 2DBH DE-MRI vs. 17.6 +/- 19.0 mL for 3DNAV DE-MRI, r(2) = 0.998, P < 0.001, N = 7) and narrow limits of agreement (-1.3 +/- 1.8 mL).
CONCLUSION: 3DNAV DE-MRI provides improved image quality and similar infarct detection in less scan time compared to the standard 2DBH DE-MRI. (c) 2008 Wiley-Liss, Inc.