Background The diameter of the left atrium (LA) is a major index
of prediction for LA fibrosis and ablation outcome in atrial
fibrillation (AF)However, an unenlarged LA may not be associated with
good results in some cases of AF ablation. Objective Exploring
the characteristics and ablation prognosis of the patients with fibrotic
but unenlarged LA Methods Patients with persistent fibrillation
who underwent catheter ablation in our center were analyzed in this
retrospective studyComprehensive low voltage mapped in LA is considered
a fibrotic LAThe patients with fibrotic but unenlarged LA, normal LA,
and fibrotic tissue with enlarged LA were included in Groups A, B, and
C, respectivelyWe compared clinical features, electrophysiological
findings, immediate ablation results, and follow-up outcomes in three
groups. Results We enrolled 9 patients in Group A, 38 in Group B, and 12
in Group CThere were greater proportions of women, low ventricular
rates, and high CHA2DS2-VASC scores in the patients with fibrotic LA
(Groups A and C)At the end of procedure, all of the patients saw
restored sinus rhythm, and the rate of sinus rhythm was lower in Groups
A and C than in Group BAtrial-ventricular block and very-early-stage
recurrence were more common in Group ASinus rhythm maintenance and LA
reversion were rarer in Group A than in Group B or C. Conclusions A
fibrotic but unenlarged LA was more likely to be seen in female with
high CHADS2VA2S scoreIt indicated a poor prognosis for AF ablation.