Clinical significance of ST-segment depression during atrial fibrillation rhythm for subsequent heart failure events.

Aims: The clinical significance of ST-segment depression during atrial fibrillation (AF) rhythm has not been fully evaluated. The aim of the present study was to explore the association of ST-segment depression during AF rhythm with subsequent heart failure (HF) events.

Methods and results: The study enrolled 2718 AF patients whose baseline electrocardiography (ECG) was available from a Japanese community-based prospective survey. We assessed the association of ST-segment depression in baseline ECG during AF rhythm with clinical outcomes. The primary ednpoint was a composite HF endpoint: cardiac death or hospitalization due to HF. The prevalence of ST-segment depression was 25.4% (upsloping 6.6%, horizontal 18.8%, downsloping 10.1%). Patients with ST-segment depression were older and had more comorbidities than those without. During the median follow-up of 6.0 years, the incidence rate of the composite HF endpoint was significantly higher in patients with ST-segment depression than those without (5.3% vs. 3.6% per patient-year, log-rank P < 0.01). The higher risk was present in horizontal or downsloping ST-segment depression, but not in upsloping one. By multivariable analysis, ST-segment depression was an independent predictor for the composite HF endpoint (hazard ratio 1.23, 95% confidence interval 1.03-1.49, P = 0.03). In addition, ST-segment depression at anterior leads, unlike inferior or lateral leads, was not associated with higher risk for the composite HF endpoint.

Conclusion: ST-segment depression during AF rhythm was associated with subsequent HF risk; however, the association was affected by type and distribution of ST-segment depression.