Atrial Fibrillation and the Risk of Sudden Cardiac Death The Atherosclerosis Risk in Communities Study and Cardiovascular Health Study AF and the Risk of Sudden Cardiac Death

Chen LY, Sotoodehnia N, Bůžková P, et al. — Mon, 14 Jan 2013 00:00:00 GMT

Background

It is unknown whether atrial fibrillation (AF) is associated with an increased risk of sudden cardiac death (SCD) in the general population. This association was examined in 2 population-based cohorts.

Methods

In the Atherosclerosis Risk in Communities (ARIC) Study, we analyzed data from 15 439 participants (baseline age, 45-64 years; 55.2% women; and 26.6% black) from baseline (1987-1989) through December 31, 2001. In the Cardiovascular Health Study (CHS), we analyzed data from 5479 participants (baseline age, ≥65 years; 58.2% women; and 15.4% black) from baseline (first cohort, 1989-1990; second cohort, 1992-1993) through December 31, 2006. The main outcome was physician-adjudicated SCD, defined as death from a sudden, pulseless condition presumed to be due to a ventricular tachyarrhythmia. The secondary outcome was non-SCD (NSCD), defined as coronary heart disease death not meeting SCD criteria. We used Cox proportional hazards models to assess the association between AF and SCD/NSCD, adjusting for baseline demographic and cardiovascular risk factors.

Results

In the ARIC Study, 894 AF, 269 SCD, and 233 NSCD events occurred during follow-up (median, 13.1 years). The crude incidence rates of SCD were 2.89 per 1000 person-years (with AF) and 1.30 per 1000 person-years (without AF). The multivariable hazard ratios (HRs) (95% CIs) of AF for SCD and NSCD were 3.26 (2.17-4.91) and 2.43 (1.60-3.71), respectively. In the CHS, 1458 AF, 292 SCD, and 581 NSCD events occurred during follow-up (median, 13.1 years). The crude incidence rates of SCD were 12.00 per 1000 person-years (with AF) and 3.82 per 1000 person-years (without AF). The multivariable HRs (95% CIs) of AF for SCD and NSCD were 2.14 (1.60-2.87) and 3.10 (2.58-3.72), respectively. The meta-analyzed HRs (95% CIs) of AF for SCD and NSCD were 2.47 (1.95-3.13) and 2.98 (2.52-3.53), respectively.

Conclusions

Incident AF is associated with an increased risk of SCD and NSCD in the general population. Additional research to identify predictors of SCD in patients with AF is warranted.

An Intersection of Atrial Fibrillation With Sudden Death Look Both Ways, and Proceed With Caution Comment on “Atrial Fibrillation and the Risk of Sudden Cardiac Death” Atrial Fibrillation With Sudden Death

Reinier K, Chugh SS. — Mon, 14 Jan 2013 00:00:00 GMT

Atrial fibrillation (AF) is the most common arrhythmia in the world, with established public health implications due to increased morbidity, hospitalization, and health care costs. Both incidence and prevalence appear to be on the rise, with an annual US incidence of 3.7 per 1000 person-years in 2000. Sudden cardiac death (SCD) is the most devastating manifestation of cardiac ventricular electrical arrhythmias; more than 95% of individuals will experience an SCD within 10 minutes of presenting with ventricular tachycardia, ventricular fibrillation, pulseless electrical activity, or asystole. Despite advances in prevention and management of sudden cardiac arrest, 300 000 to 350 000 US lives are lost annually due to SCD, constituting approximately 50% of overall mortality from cardiovascular disease. As a consequence, the potential intersection of these two important conditions has long been of interest to investigators in either field. While an independent relationship between AF and overall mortality has been reported, an independent association between AF and the subgroup of patients with SCD had not been demonstrated.

JAMA Internal Medicine: Cardiac Arrest/Resuscitation Topic Collection

Atrial Fibrillation and the Risk of Sudden Cardiac Death The Atherosclerosis Risk in Communities Study and Cardiovascular Health Study AF and the Risk of Sudden Cardiac Death

An Intersection of Atrial Fibrillation With Sudden Death Look Both Ways, and Proceed With Caution Comment on “Atrial Fibrillation and the Risk of Sudden Cardiac Death” Atrial Fibrillation With Sudden Death