Influence of left atrial size on the outcome of pulmonary vein isolation in patients with atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the most frequent sustained supraventricular tachyarrhythmia. Radiofrequency (RF) ablation is one of the options used to prevent the recurrence of AF. Despite thorough studies, the relation between left atrial (LA) size and the results of RF ablation remains controversial. AIM: To estimate the relation between LA size assessed by echocardiography and the AF recurrence rate after pulmonary vein isolation (PVI).
METHODS: Our analysis comprised 175 AF patients subjected to PVI between June 2011 and March 2012. Inclusion criteria comprised: symptomatic AF with no reversible cause, and age < 70, LA < 5.5 cm (anteroposterior). PVI was performed with a 4-mm non-irrigated catheter or irrigated catheter and circular mapping catheter (electroanatomic mapping with LocaLisa or CARTO systems). Recurrence was defined as any atrial tachyarrhythmia episode that lasted more than 30 s after three months of blanking period. Standard echocardiographic post-ablation anteroposterior LA measurements were performed with additional parameters such as systolic and diastolic LA area and volume (on sinus rhythm).
RESULTS: The analysis included 198 procedures performed in 175 patients. Median follow-up time was 17 months. Median age was 56 years. After the first procedure, AF recurred in 88 (52.4%) patients. Efficacy after the last procedure was 55.2% (43.5% for persistent AF and 59.7% for paroxysmal AF). No significant relation between any of the LA parameters and the recurrence rate was found. Cox univariate and multivariate analysis revealed only very early AF recurrence as a prognostic factor for AF recurrence in the long term.
CONCLUSIONS: In patients with AF, no relation could be observed between the recurrence rate after PVI and the echocardiographic LA measurement parameters.