Device-recognized atrial fibrillation (AFib) may be associated with a higher risk of all-cause mortality in patients with cardiac implantable electronic devices (CIEDs), according to a study published in Circulation.

Graham Peigh, MD, et al., used data collected in the Optum Clinformatics U.S. claims data on patients with CIEDs capable of continuous arrythmia detection implanted between October 2016 and September 2019 to assess the association between device-recognized AFib, compared with no AFib.

Results showed that of 21,391 patients (56.3% men, 72.9 years old), 36.5% had device-recognized AFib. Most had paroxysmal AFib (76.5%), and 14.7% had persistent AFib and 8.8% had permanent AFib. The most common comorbidities in the overall cohort were hypertension (86.4%), coronary artery disease (50.1%) and heart failure (44.4%).

During a mean follow-up of 22.4 months, the overall incidence of all-cause mortality was 13.5%. Patients with vs. those without AFib had higher adjusted all-cause mortality (hazard ratio [HR], 1.29; 95% CI, 1.20-1.39; p<0.001).

Looking at secondary outcomes, relative mortality was higher in those with nonparoxysmal AFib, either persistent (24.9%) or permanent (20.7%), compared with paroxysmal AFib (14.3%). The HR for persistent vs. paroxysmal AFib was 1.36 and for permanent vs. paroxysmal AFib was 1.23; p<0.001 for both.

After adjusting for cardiovascular comorbidities in the CHA₂DS₂-VASc score and demographic factors, presence of AFib, vs. no AFib, continued to be associated with higher all-cause mortality (HR, 1.38; p<0.001). Risk of death was higher in those with permanent AFib and lowest with paroxysmal AFib.

The authors note this is the first study to their knowledge that provides current data on the association between mortality and different types of AFib. They also point to the importance of rhythm control as a possible intervention. "Because previous studies have demonstrated a mortality benefit of rhythm control for [AFib] (thereby lowering [AFib] burden) in populations with heart failure, the results of the current study are hypothesis generating to suggest that rhythm control interventions to lower [AFib] burden may confer mortality benefits in allcomers with CIEDs."