The Natural History of Multifocal Atrial Rhythms in Elderly Outpatients: Insights from the "Ikaria Study"

Background Multifocal atrial tachycardias confer an adverse prognosis in hospitalized patients. We assessed the prognostic impact of multifocal atrial rhythms (MARs—either chaotic atrial rhythm or multifocal atrial tachycardia/bradycardia) in very elderly outpatients. Methods One hundred ten subjects aged 60–74 years, 112 aged 75–89 years, and 61 over 90 years old, were enrolled and prospectively evaluated. Several demographic and clinical characteristic were recorded in all individuals. Results A high prevalence of MARs was detected in the study population (namely, 6%), which in subjects >90 years was even higher (15%). Individuals with MARs were older, more often female and less active. In multivariate analysis, independent predictors of MARs were age (OR = 1.07, 95% CI: 1.02–1.13, P = 0.01) and female sex (OR = 4.77, 95% CI: 1.23–18.48, P = 0.02). The mortality rate during the follow‐up period was 8.4% without differences between age groups (P = 0.209). In particular, mortality rate was 6% in individuals with MARs and 9% in those without (P = 0.72). Mortality was associated with age (OR 1.07, 95% CI: 1.02–1.12, P = 0.005) and history of cardiovascular disease at baseline (OR 4.57, 95% CI: 1.87–11.2 P = 0.001). Conclusions Contrary to hospitalized individuals with multifocal atrial tachycardias, MARs were not associated with increased mortality in elderly outpatients in this study.