Study limitations
Firstly, although the relatively small number of subjects might
underpower the statistical analysis, in this per-segments analysis, 768
regions were considered, which in turn could improve statistical
confidence. Secondly, Imp-min and late recurrence had an associative
tendency, although not significant in the segments other than SAE, which
might be derived from a small number of subjects for statistics.
Thirdly, acute PVRs were distributed heterogeneously; therefore, it was
preferable to assess each segment to clarify the regional difference in
the characteristics of acute PVRs, which requires more number of
subjects for evaluation. Lastly, if the impedance-guided HPSD procedure
is warranted for clinical practice, its safety aspects, especially
regarding esophageal injury, should be assessed as they have not been
sufficiently evaluated to date.