Study limitations:
An important limitation of our study is its single-center design and
relatively small study group. In addition, this is not a prospective
clinical study indicating the relationship between ECG parameter and
long term prognosis. As our measurement method using the
electrophysiological recording system is extremely precise we are aware,
that our results could not be comparable directly to the results of
other authors. We’ve already mentioned, the duration of persistent form
of the arrhythmia could not be exactly estimated. Because our hypothesis
is the prolongation of the duration of the P wave is mainly related to
atrial fibrillation itself, it should be assumed as the main limitation
of our study, even if the literature data contradict the correlation
between the arrhythmia duration and P wave prolongation [16].