4.2 The anatomical differences between MPL and CPL
The distance from the posterior line to the anterior aspect of the
esophagus was mainly contributed by the myocardium of the LAPW, parietal
pericardium, and the fibrofatty
tissue.13 However, the
parietal pericardium was identified via histological examination,
whereas it was almost impossible to identify this parameter from the CT
images in the narrow space between LAPW and the esophagus. In the CT
image analyses, the myocardium and the fat pad were the main evaluating
factors for the distances. Previous studies indicated that the CPL
overlap with the LAPW might be responsible for the esophageal injury and
even the atrial-esophageal fistula
(AEF).8,
17 Moreover, the location of the AEF was
commonly related to the ablation lines of the left inferior PV-LA
junctions.17,
18 In our study, instead of CPL, we
employed MPL, defined by starting at the anterior-inferior part of left
PV, which was at a longer distance from the esophagus (Figure 1).
Therefore, the esophagus was separated from LAPW by the left inferior
PV, which protected it from ablation injury.