Arrhythmias & electrophysiologyResearch article
Prognostic value of electrocardiogram (ECG)-derived f-wave indices from implantable loop recorder: Analysis from the LOOP study
- Analysis from the LOOP study
- Multivariate Cox regression
Authors' conclusion
In screening-detected AF, indices of a more organized fibrillatory process (low AFR/ExpDec) and advanced structural abnormalities (low FWA) were associated with increased mortality and heart failure events. F-wave analysis identifies high-risk patients in early AF, potentially enabling targeted interventions.
Study context
- Population
- LOOP study participants with implantable loop recorders (ILR) and no prior atrial fibrillation (AF)758 men, median age 73 years, AF episodes ≥60 minutes detected in 96 patients (6.8%)
- Participants
- 1,411 participants
- Comparison
- Low vs higher ILR ECG-derived f-wave indices
- Outcome
- All-cause mortality
Main finding
As reported in the abstract
Low atrial fibrillatory rate (AFR) (<317 fpm): HR [95% CI]
2.5 [1.3-4.8]
Low ExpDec (<1.25): HR [95% CI]
2.8 [1.4-5.5]
Low FWA (<97 μV): HR [95% CI]
2.7 [1.4-5.4]
Secondary outcomes
Composite of cardiovascular death (CVD) or heart failure hospitalization (secondary end point)
- Low AFR: HR [95% CI]
- 4.0 [1.6-9.9]
- Low ExpDec: HR [95% CI]
- 3.7 [1.4-10.1]
- Low FWA: HR [95% CI]
- 2.9 [0.97-8.6]
- larger uncertainty
Correlation of FWA with left atrial volume
- significant, yet modest, negative correlation
Original publication
Summarised from the published abstract; every number is checked against it