4.6 Limitations
In our study we found a significant proportion of patients with PMF
after conventional proof of complete block. However, we cannot ignore
the fact that there may be cases with pseudo-block without subsequent
PMF recurrence, as the re-induction challenge was performed only after
AT ablation and not systematically in the context of AF ablation.
Regarding patients who developed PMF after confirmation of MI block in
the same procedure, the recurrence of MI conduction in an “on-off”
manner probably cannot be excluded, although the pacing confirmation was
always performed very close to PMF occurrence. On the other hand,
patients who developed PMF in another procedure and were found from the
beginning to meet the pacing criteria for MI block should confidently be
considered to have MI pseudo-block.
Another limitation is that the CV measurement is governed by subjective
selection of the acquired points. By taking different points for this
measurement or even by shifting the timing of the isochronal scale it
can lead to significant differences in the CV value. However, all these
measurements were made in high-density activation maps, a fact that
mitigates the subjectivity in CV evaluation. In addition, the
significant difference found between PMFs with ΜΙ pseudo-block and usual
PMFs that occur after AF ablation probably circumvents the above
limitation.