Atrial fibrillation burden >6 minutes on a simulated 14-day ECG monitor was associated with a higher rate of stroke or systemic embolism than <6 minutes (adjusted HR 3.02; 95% CI 1.39-6.56).
Cohort (n=2,470)
Does an atrial fibrillation burden >6 minutes detected by a 14-day ECG monitor increase the risk of ischaemic stroke or systemic embolism in patients >65 years old with hypertension and a pacemaker?
In older patients with hypertension and a pacemaker, detecting >6 minutes of atrial fibrillation on a simulated 14-day ECG monitor is associated with a 3-fold increased risk of stroke or systemic embolism.
Effect estimate: adjusted HR 3.02 (95% CI 1.39-6.56)
Absolute Event Rate: 2.18% vs 0.7%
AIMS: There is uncertainty about whether and how to perform screening for atrial fibrillation (AF). To estimate the incidence of previously undetected AF that would be captured using a continuous 14-day ECG monitor and the associated risk of stroke. METHODS AND RESULTS: We analysed data from a cohort of patients >65 years old with hypertension and a pacemaker, but without known AF. For each participant, we simulated 1000 ECG monitors by randomly selecting 14-day windows in the 6 months following enrolment and calculated the average AF burden (total time in AF). We used Cox proportional hazards models adjusted for CHA2DS2-VASc score to estimate the risk of subsequent ischaemic stroke or systemic embolism (SSE) associated with burdens of AF > and 6 min was 3.10% (95% CI 2.53-3.72). This was consistent across strata of age and CHA2DS2-VASc scores. Over a mean follow-up of 2.4 years, the rate of SSE among patients with 6 min of AF. CONCLUSIONS: Approximately 3% of individuals aged >65 years with hypertension may have more than 6 min of AF detected by a 14-day ECG monitor. This is associated with a stroke risk of over 2% per year. Whether oral anticoagulation will reduce stroke in these patients is unknown.
McIntyre et al. (Tue,) conducted a cohort in hypertension and a pacemaker, but without known AF (n=2,470). AF burden >6 min vs. AF burden <6 min was evaluated on subsequent ischaemic stroke or systemic embolism (SSE) (adjusted HR 3.02, 95% CI 1.39-6.56). Atrial fibrillation burden >6 minutes on a simulated 14-day ECG monitor was associated with a higher rate of stroke or systemic embolism than <6 minutes (adjusted HR 3.02; 95% CI 1.39-6.56).