Atrial fibrillation linked to sudden cardiac deathBMJ 2012; 345 doi: http://dx.doi.org/10.1136/bmj.e8029 (Published 28 November 2012) Cite this as: BMJ 2012;345:e8029
Adults with atrial fibrillation were two to three times more likely to die suddenly of a presumed cardiac arrhythmia than similar adults without atrial fibrillation in an analysis of two large US cohorts. The association seemed independent of other risk factors for sudden cardiac death, including hypertension, diabetes, coronary heart disease, heart failure, and left ventricular hypertrophy. In the younger cohort (45-64 years at baseline), incidences of sudden cardiac death were 2.89 per 1000 person years for adults with atrial fibrillation and 1.30 per 1000 person years for adults without atrial fibrillation. Absolute risks were higher in the older cohort, all of whom were at least 65 years of age when recruited. The authors report a fully adjusted hazard ratio of 2.47 (95% CI 1.95 to 3.13) for both cohorts combined, during an average follow-up of 13 years. The link between atrial fibrillation and sudden cardiac death was similar in men and women.
Sudden cardiac death can be added to the list of serious outcomes already associated with atrial fibrillation, such as stroke, heart failure, and death from all causes, says a linked editorial (doi:10.1001/jamainternmed.2013.1774). But doctors can do little to reduce risk until we know whether atrial fibrillation is a predictor or a cause of lethal ventricular arrhythmias. Both options are still possible.
These authors were unable to capture asymptomatic atrial fibrillation or atrial fibrillation managed exclusively in outpatient or primary care clinics. Most cases of new atrial fibrillation in these cohorts were identified from hospital discharge records.
Cite this as: BMJ 2012;345:e8029