Prognostic Importance of Atrial Fibrillation Timing and Pattern in Adults With Congestive Heart Failure: A Systematic Review and Meta-Analysis

•Atrial fibrillation (AF) was associated with an increased risk of mortality.•The risk of mortality was greater in incident AF compared with prevalent AF.•The risk of mortality did not vary by the pattern of AF.•AF in congestive heart failure was associated with an increased risk of cardiovascular mortality and stroke.

BackgroundAtrial fibrillation (AF) is common among adults with congestive heart failure (CHF). We conducted a meta-analysis to summarize the risk of mortality and cardiovascular disease associated with AF in CHF and stratified our analyses by AF timing and pattern.MethodsWe searched MEDLINE and EMBASE for observational studies examining the association of AF with cardiovascular disease and death. Eligible studies had a minimum of 50 participants with AF and 50 participants without AF, and a median follow-up of 6 months.ResultsThirty-three studies involving 114,204 adults (43,549 with AF) were included in this meta-analysis. AF was associated with an increased risk of mortality and this risk varied between incident and prevalent AF (relative risk 2.21, 95% confidence interval 1.96-2.49 vs relative risk 1.19, 95% confidence interval 1.03-1.38, respectively; P < .001 for interaction). The risk of mortality associated with incident AF was consistent in adults with CHF with reduced and preserved ejection fraction. The relative risk of mortality did not vary between paroxysmal and chronic AF. Finally, AF was associated with an increased risk of cardiovascular mortality and stroke.LimitationUse of anticoagulation was infrequently reported in included studies.ConclusionsAF was associated with an increased risk of cardiovascular disease and death and, notably, the risk of mortality varied by AF timing.