Markers for silent atrial fibrillation in esophageal long-term electrocardiography

- Esophageal long-term ECG (eECG) is an unusual method but provides excellent (left) atrial ECG signals and only minimal patient discomfort.
- During sinus rhythm, eECG identifies patients more likely to have paroxysmal atrial fibrillation.
- In particular partially A-V blocked atrial runs and atrial signal duration - revealed by eECG - are highly specific surrogate markers for paroxysmal atrial fibrillation.

PurposeParoxysmal atrial fibrillation (PAF) often remains undiagnosed. Long-term surface ECG is used for screening, but has limitations. Esophageal ECG (eECG) allows recording high quality atrial signals, which were used to identify markers for PAF.MethodsIn 50 patients (25 patients with PAF; 25 controls) an eECG and surface ECG was recorded simultaneously. Partially A-V blocked atrial runs (PBARs) were quantified, atrial signal duration in eECG was measured.ResultseECG revealed 1.8‰ of atrial premature beats in patients with known PAF to be PBARs with a median duration of 853 ms (interquartile range (IQR) 813-1836 ms) and a median atrial cycle length of 366 ms (IQR 282-432 ms). Even during a short recording duration of 2.1 h (IQR 1.2-17.2 h), PBARs occurred in 20% of PAF patients but not in controls (p = 0.05). Left atrial signal duration was predictive for PAF (72% sensitivity, 80% specificity).ConclusionseECG reveals partially blocked atrial runs and prolonged left atrial signal duration - two novel surrogate markers for PAF.