A Quarter of Patients With Implantable Electronic Devices Have Subclinical AF

A study was conducted to determine the epidemiology of subclinical atrial fibrillation in patients with cardiac implantable electronic devices.

According to results of a systematic review and meta-analysis published in the European Journal of Internal Medicine, subclinical atrial fibrillation (AF) is common among patients with cardiac implantable electronic devices (CIEDs).

Publication databases were searched through August 2021 for studies of subclinical AF in patients with CIEDs. The prevalence of subclinical AF and potential risk factors were evaluated using data from 54 publications and 72,784 patients.

The trials were of observational retrospective (n=30), observational prospective (n=16), and randomized controlled trial (n=8) designs.

The overall prevalence of subclinical AF was 28.1% (95% CI, 24.3%-32.1%; I2, 98.3%).

In the subgroup analyses, the pooled prevalence of subclinical AF was 31.0% for Asia, 30.2% for North America, 24.4% for Europe, and 28.0% for other regions.

Stratified by type of CIEDs, the rate was highest for pacemakers (32.2%), followed by cardiac resynchronization therapy (28.8%), mixed (25.5%), and implantable cardiac devices (18.7%).

The rate of subclinical AF was higher in studies which used a device-based definition (29.0%) compared with manual confirmation (27.1%). The rate was highest in studies using an atrial rate cutoff of less than 180 beats per minute (bpm; 30.7%) and lowest for a cutoff of over 200 bpm (25.0%). It was also highest for a cutoff duration of less than 5 minutes (34.3%) and lowest for a cutoff duration of 5 to 6 minutes (25.7%).

Subclinical AF was associated with history of atrial fibrillation (odds ratio [OR], 4.39; 95% CI, 2.73-7.07; I2, 85%), congestive heart failure (OR, 1.39; 95% CI, 1.06-1.83; I2, 62%), stroke or transient ischemic attack (OR, 1.17; 95% CI, 1.03-1.33; I2, 0%), and hypertension (OR, 1.14; 95% CI, 1.04-1.25; I2, 23%), as well as older age (OR, 1.36; 95% CI, 0.40-2.32; I2, 85%) and higher CHA2DS2-VASc score (OR, 0.23; 95% CI, 0.14-0.32; I2, 39%).

This analysis is limited by the high amount of heterogeneity observed among the studies.

“In this systematic review and meta-regression analysis, [subclinical] AF increased with age and decreased over longer follow-up times, both being independently associated with its prevalence,” the study authors wrote. “The presence of [subclinical] AF is associated with higher age, more prevalent comorbidities, and higher thromboembolic risk.”

Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.


Proietti M, Romiti GF, Vitolo M, et al. Epidemiology of subclinical atrial fibrillation in patients with cardiac implantable electronic devices: a systematic review and meta-regression. Eur J Intern Med. Published online July 8, 2022. doi:10.1016/j.ejim.2022.06.023