Atrial fibrillation after ischemic stroke detected by chest strap-style 7-day holter monitoring and the risk predictors: Educateesus

Aim: This study aimed to investigate the diagnostic yield of 7-day Holter monitoring for detecting covert atrial fibrillation (AF) in patients with recent embolic stroke of undetermined source (ESUS) and to identify the preentry screening biomarkers that had significant associations with later detection of AF (clinicaltrials.gov. NCT02801708). Methods: A total of 206 patients who have recent ESUS without previously documented AF underwent Holter electrocardiography using a chest strap-style monitor. External validation of biomarkers predictive of AF was performed using 83 patients with ESUS who were implanted with insertable cardiac monitors. Results: The 7-day Holter monitoring started at a median of 13 days after the onset of stroke. AF was detected in 14 patients, and three of these showed a single AF episode lasting <2 min. The median time delay to the first documented AF was 50 h. Each of serum brain natriuretic peptide > 66.0 pg/mL (adjusted odds ratio 5.23), atrial premature contractions (APCs) = 345 beats (3.80), and APC short runs = 13 (5.74) on 24-h Holter prior to the 7-day Holter showed a significant association with detection of AE independent of age and physiological findings in this derivation cohort, and all of these showed a significant association in the validation cohort (adjusted odds ratio 6.59, 7.87, and 6.16, respectively). Conclusions: In recent ESUS patients, the detection rate of AF using the 7-day Holter monitoring was 6.8% (95% CI 4.1%-11.1%). Brain natriuretic peptide, APC count, and APC short runs in the standard clinical workup seemed to be predictors of covert AE.