New-Onset Atrial Fibrillation After TAVI Studied

January 10, 2012—In the Journal of the American College of Cardiology, Ignacio J. Amat-Santos, MD, et al published findings from a study that sought to evaluate the incidence, predictive factors, and prognostic value of new-onset atrial fibrillation (AF) after transcatheter aortic valve implantation (TAVI) (2012;59:178–188).

According to the investigators, very few data exist on the occurrence of new-onset AF after TAVI. In the study, a total of 138 consecutive patients with no history of AF underwent TAVI with a balloon-expandable valve. Patients were on continuous electrocardiography monitoring until hospital discharge, and new-onset AF was defined as any episode of AF lasting > 30 seconds. All clinical, echocardiographic, procedural, and follow-up data were prospectively collected.

The investigators reported that new-onset AF occurred in 44 patients (31.9%) at a median time of 48 hours (interquartile range, 0–72 h) after TAVI. The predictive factors of new-onset AF were left atrial (LA) size (odds ratio [OR], 1.21 for each increase in 1 mm/m²; 95% confidence interval [CI]: 1.09–1.34; P < .0001) and transapical approach (OR, 4.08; 95% CI: 1.35–12.31; P = .019). At 30-day follow-up, new-onset AF was associated with a higher rate of stroke/systemic embolism (13.6% vs 3.2%; P = .021; P = .047 after adjustment for baseline differences between groups), with no differences in mortality rate between groups (new-onset AF, 9.1%; no–new-onset AF, 6.4%; P = .57).

At a median follow-up of 12 months (interquartile range, 5–20 months), a total of 27 patients (19.6%) had died, with no differences between the new-onset AF (15.9%) and no–new-onset AF (21.3%) groups (P = .58). The cumulative rates of stroke and stroke/systemic embolism at follow-up were 13.6% and 15.9%, respectively, in the new-onset AF group versus 3.2% in the no–new-onset AF group (P = .039; adjusted P = .037 for stroke; P = .02; adjusted P = .023 for stroke/systemic embolism).

The data showed that new-onset AF occurred in approximately one-third of the patients with no previous AF undergoing TAVI, and its incidence was increased in patients with larger LA size and those undergoing transapical TAVI. New-onset AF was associated with a higher rate of stroke/systemic embolism but not higher mortality at 30 days and at 1-year follow-up, concluded the investigators.

In an editorial comment in the Journal of the American College of Cardiology, Bernard Iung, MD, Dominique Himbert, MD, and Alec Vahanian, MD, stated that the paper deserves attention because of its originality and its potential implications concerning postprocedural management of patients undergoing TAVI (2012;59:189–190). They commented, “The paper by Amat-Santos et al has the merit of drawing attention to the frequency and the potential impact of AF occurring after TAVI. The potential contribution of postprocedural AF to the occurrence of stroke after TAVI highlights the need to improve the identification of patients at risk, to test pharmacological approaches to reduce the incidence of AF, and to conduct randomized trials to refine antithrombotic therapy in this setting.”