The Spatial Distribution of Late Gadolinium Enhancement of Left Atrial Magnetic Resonance Imaging in Patients With Atrial Fibrillation.

OBJECTIVES

The purpose of this study is to evaluate the spatial distribution of late gadolinium enhancement (LGE) of the left atrium (LA) by LGE-magnetic resonance imaging in an atrial fibrillation (AF) population.

BACKGROUND

LGE of the LA can be a surrogate of pre-existing structural remodeling of LA.

METHODS

LGE-magnetic resonance imaging scans were used for 160 patients with AF (mean age 66 ± 11 years) before AF ablation. To know the spatial distribution of LGE, the extent of LGE in 6 LA subregions was examined. Overall LGE distribution was also summarized as a spatial frequency histogram using an atlas of LA shape. These data were also compared between paroxysmal AF (87 patients) and persistent AF (73 patients).

RESULTS

LGE coverage (%) in each subregion was as follows: 41.8 ± 18.9% in the left pulmonary vein (PV) antrum, 27.1 ± 16.7% in the left lateral wall, 25.8 ± 15.3% in the posterior wall, 19.7 ± 15.3% in the anterior wall, 17.1 ± 15.0% in the right PV antrum, and 12.0 ± 13.2% in the septum wall. LGE was heterogeneously distributed in the LA and was found with the highest frequency in the posterior wall near the inferior left PV antrum by the LGE histogram. A comparison of paroxysmal AF with persistent AF suggests that LGE was more expected in persistent AF compared with paroxysmal AF, particularly with a spread on the posterior and the anterior wall.

CONCLUSIONS

LGE in the LA was heterogeneously distributed. LGE was highly distributed in the inferior left PV antrum near the posterior wall side, and spread on the posterior and anterior wall with AF progression.