Incidence and predictors of atrial fibrillation following transcatheter closure of interatrial septal communications using contemporary devices.

Background: Transcatheter closure of interatrial septal communications (IASC) is being increasingly performed, while less is known about predictors and incidence of new onset atrial fibrillation (AF) after device closure. Hitherto, most studies have only analyzed some parameters potentially influencing the occurrence of AF, variously omitting others and thus limiting interpretation of results.

Methods: Descriptive, single author, observational study with 68 consecutive patients [aged 53.6 +/- 15.1 years; 32 females (47%)] undergoing IASC closure, being followed up for 16.8 (+/-9.9; 6-42) months. Two patients with AF previous to device implantation had been excluded. Parameters analyzed included age and gender as well as presence of coronary artery disease, hypertension, atrial size, body mass index, device size, and presence of residual shunt. Device size was normalized to maximal disk diameter as declared by the manufacturer.

Results: The incidence of new onset AF was 10.3% in the first 6 months after IASC closure. The only two predictors linked to AF were device size (P = 0.002) and, although not reaching significance level, right atrial dilatation (P = 0.08).

Conclusion: Occluder size was the only significant predictor of post-procedural AF, especially after PFO closure. Although there may be constraints (defect size, presence of an atrial septal aneurysm) that may dictate implantation of a larger device, it is reasonable to implant them "as large as necessary, as small as possible". The influence of atrial dimensions on post-procedural onset of AF must be further investigated.