Different Impact of Resting Heart Rate on Adverse Events in Paroxysmal and Sustained Atrial Fibrillation - The Fushimi AF Registry

The impact of visit-to-visit heart rate variability on all-cause mortality in atrial fibrillation

OBJECTIVE

We aimed to investigate the association between visit-to-visit heart rate variability (VVHRV) and all-cause mortality in patients diagnosed with atrial fibrillation (AF). Previous studies have shown a positive correlation between VVHRV and several adverse outcomes. However, the relationship between VVHRV and the prognosis of AF remains uncertain.

METHODS

In our study, we aimed to examine the relationship between VVHRV and mortality rates among 3983 participants with AF, who were part of the AFFIRM study (Atrial Fibrillation Follow-Up Investigation of Rhythm Management). We used the standard deviation of heart rate (HRSD) to measure VVHRV and divided the patients into four groups based on quartiles of HRSD (1st, <5.69; 2nd, 5.69-8.00; 3rd, 8.01-11.01; and 4th, ≥11.02). Our primary endpoint was all-cause death, and we estimated the hazard ratios for mortality using the Cox proportional hazard regressions.

RESULTS

Our analysis included 3983 participants from the AFFIRM study and followed for an average of 3.5 years. During this period, 621 participants died from all causes. In multiple-adjustment models, we found that the lowest and highest quartiles of HRSD independently predicted an increased risk of all-cause mortality compared to the other two quartiles, presenting a U-shaped relationship (1st vs 2nd, hazard ratio = 2.28, 95% CI = 1.63-3.20, p < .01; 1st vs. 3rd, hazard ratio = 2.23, 95% CI = 1.60-3.11, p < .01; 4th vs. 2nd, hazard ratio = 1.82, 95% CI = 1.26-2.61, p < .01; and 4th vs. 3rd, hazard ratio = 1.78, 95% CI = 1.25-2.52, p < .01).

CONCLUSION

In patients with AF, we found that both lower VVHRV and higher VVHRV increased the risk of all-cause mortality, indicating a U-shaped curve relationship.

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.

Prognostic impact of heart rate during atrial fibrillation on clinical outcomes in elderly non-valvular atrial fibrillation patients: ANAFIE Registry sub-cohort study

BACKGROUND

Elderly patients with atrial fibrillation (AF) are at a higher risk for all-cause mortality and heart failure. Rate control is an essential component in AF management. This exploratory study assessed the relationship between resting heart rate during AF at baseline and clinical outcomes in Japanese elderly non-valvular AF (NVAF) patients, using the All Nippon AF In the Elderly Registry (ANAFIE) dataset.

METHODS

This sub-cohort included patients who agreed to participate and presented with AF at enrollment in the ANAFIE study. They were categorized into six groups according to the resting heart rate during AF. Outcomes included 2-year cumulative incidences of stroke/systemic embolic events (SEE), ischemic stroke, major bleeding, cardiovascular (CV) events, CV death, all-cause death, and net clinical outcome, a composite of stroke/SEE, major bleeding, and all-cause death.

RESULTS

Of the 8292 patients included in this sub-cohort (paroxysmal, 1496; non-paroxysmal, 6796), 90 % of patients were using anticoagulants. Higher heart rate was more frequently reported in women and in patients with paroxysmal AF and was associated with increased use of direct oral anticoagulants (DOACs) and antiarrhythmic drugs. Heart rate ≥110 beats per minute (bpm) was associated with a significantly higher incidence of cardiac events and numerically higher incidences of CV death and all-cause death compared with a heart rate of 60 to <80 bpm, all of which were driven by an increased risk in patients with non-paroxysmal AF. Hazard ratios by the type of anticoagulant for each clinical outcome were comparable across all heart rate categories, indicating no significant interactions.

CONCLUSIONS

Elderly Japanese patients with non-paroxysmal NVAF and a heart rate ≥110 bpm have an increased risk of cardiac events. There was no interaction between heart rate category and the relative risk of adverse clinical events in patients taking DOACs compared with those taking warfarin.

Association of inverted T wave during atrial fibrillation rhythm with subsequent cardiac events

OBJECTIVE

The clinical significance of ECG abnormalities during atrial fibrillation (AF) rhythm is poorly understood. The aim of the current study was to explore the impact of inverted T wave on cardiac prognosis in patients with AF.

METHODS

The current study enrolled 2709 patients with AF whose baseline ECG was available from a Japanese community-based prospective survey, the Fushimi AF Registry, and the impact of inverted T wave in baseline ECG at AF rhythm on the composite of cardiac death, myocardial infarction and hospitalisation due to heart failure was examined.

RESULTS

Intraventricular conduction delay, ST segment depression and inverted T wave were observed in 15.8%, 24.7% and 41.4% of baseline ECG with a mean heart rate of 94.7 beats per minute. The median follow-up duration was 5.0 years. The incidence rate of the composite cardiac endpoint was significantly higher in patients with inverted T wave than those without (5.8% vs 3.3% per patient-year, log-rank p<0.01). The higher risk associated with inverted T wave was consistent even for individual components of the composite cardiac endpoint. By multivariable analysis, inverted T wave was an independent predictor of the composite cardiac endpoint (HR 1.53, 95% CI 1.26 to 1.85, p<0.01). Inverted T wave was detected in 15.7% at anterior leads, 19.8% at inferior leads and 26.6% at lateral leads. The location of inverted T wave was not associated with risk of composite cardiac endpoint.

CONCLUSIONS

Inverted T wave was commonly observed in patients with AF and its presence during AF rhythm was associated with subsequent cardiac events.