4.3 Correlation between the AWT and fibrosis
A recent study showed that a thicker LA wall was associated with a
stronger atrial maintenance substrate in patients with LA enlargement
assessed by echocardiography.15 An enlarged LA and a
thickened LA wall might seem to be contradicted. A thickened LA wall may
implicate the stage of inflammation, edema. With the progression of AF
to end-stage disease, remodeling may advance to atrial fibrosis, leading
to a thinner AWT. Moreover, the observation of fractionated electrical
activity with a low voltage on the electroanatomic map may be predictive
of a high risk of AF initiation and persistence. The loss of an adaptive
atrial thickening may be the tipping point at which fibrosis and scar
become irreversible.16 In our study, the LA wall
thickness was negatively correlated with the LGE-volume ratio and the
correlation was significant at only the NPAs but not the PAs, which was
consistent with these previous results.