Obesity surgery and incidence of atrial fibrillation

Abstract

rillation. Data from clinical trials suggest that both rate and rhythm control are acceptable approaches with comparable rates of mortality in the short term, but it is unclear whether stroke rates differ between patients who filled prescriptions for rhythm or rate control therapy. A recent observational analysis has found lower rates of stroke with rhythm control. Methods: We examined the clinical course of 6,068 consecutive patients with AF with a diagnosis of atrial fibrillation seen in a cardiology department during the period 2000 to 2010 with the use of linked administrative data from hospital discharge and drug prescription. We compared rates of stroke or thromboembolic events (TE) among patients using rhythm (class Ia, Ic, and III antiarrhythmic agents), versus rate control (Beta-blockers, calcium channel blockers, and digoxin) treatment strategies (either current or new users). The cohort consisted of 2,374/6,068 patients who filled a prescription for rhythm control therapy (with or without rate control therapy, n=2182) and/or had AF radiofrequency ablation (n=260), and 3,694/6,068 patients who filled a prescription for rate control therapy. Results: In patients on rhythm control therapy, CHA2DS2VASc score was higher than on rate control therapy (3.2±1.8 versus 3.1±1.8, p=0.03) and treatment with any antithrombotic drug was more frequent (90% in rhythm control versus 78% in rate control group, p<0.0001). Mean follow-up was 2.5 years (maximum 10.0 years) and 477 stroke/TE were recorded. Crude stroke/TE incidence rate was similar in patients treated with rhythm control in comparison with rate control therapy (2.97 versus 3.53, per 100 person-years, p=0.12). This finding was not different in patients in the moderateand high-risk groups for stroke according to the CHA2DS2VASc risk score. In multivariable Cox regression analysis, rhythm control therapy was not associated with a significantly lower risk of stroke/TE after adjustment for age, CHA2DS2VASc and HAS BLED scores, use of cardiovascular medications and other confounders in comparison with rate control therapy (adjusted hazard ratio, 0.88; 95% confidence interval, 0.72-1.09). Conclusions: In comparison with rate control therapy, the use of rhythm control therapy was not associated with lower rates of stroke/TE among patients with atrial fibrillation. Antithrombotic strategy should not be influenced by rhythm strategy in atrial fibrillation.