Atrial fibrillation is a marker of increased mortality risk in nonischemic heart failure-Results from the DANISH trial

Nocturnal Cardiac Arrhythmias in Heart Failure With Obstructive and Central Sleep Apnea

BACKGROUND

Both obstructive and central sleep apnea (CSA) may contribute to nocturnal cardiac arrhythmias (NCAs). Data are scarce regarding the prevalence of clinically important nocturnal atrial and ventricular arrythmias in patients with heart failure with reduced ejection fraction (HFrEF) and OSA or CSA.

RESEARCH QUESTION

In a cohort of patients with HFrEF, how does the prevalence of NCA compare among those with OSA, CSA, and those with no to mild sleep apnea? Is the severity of OSA or CSA associated with atrial and ventricular NCAs?

STUDY DESIGN AND METHODS

This cross-sectional analysis is an ancillary study of the Effect of Adaptive Servo Ventilation on Survival and Hospital Admissions in Heart Failure (ADVENT-HF) trial. We compared the prevalence of NCAs (excessive supraventricular ectopic activity [ESVEA], defined as premature atrial complexes ≥ 30/h or supraventricular tachycardia ≥ 20 beats); atrial fibrillation/flutter [AF]; and > 10 premature ventricular complexes [PVCs/h]) on ECGs from polysomnograms of patients with HFrEF between those with OSA (apnea-hypopnea index [AHI ≥ 15 events/h]), those with CSA (AHI ≥ 15 events/h), and those with no to mild sleep apnea (AHI < 15 events/h [control]).

RESULTS

The prevalence of ESVEA was higher in patients with OSA (n = 430) and CSA (n = 150) compared with control participants (n = 76): 0%, 9%, and 12%, respectively. The prevalence of AF in the control, OSA, and CSA groups was 9%, 17%, and 27%; the prevalence of > 10 PVCs/h was 45%, 59%, and 63%. In multivariable regression analyses, premature atrial complexes/h was associated with OSA severity (obstructive AHI: 22.4% increase per 10 events/h [95% CI, 5.2-42.3; P = .009), although neither obstructive nor central AHI was associated with AF or > 10 PVC/h.

INTERPRETATION

In patients with HFrEF, the prevalences of nocturnal ESVEA, AF, and PVC > 10/h were higher in those with OSA or CSA than in those without OSA or CSA, and OSA severity was related to the burden of nocturnal atrial ectopy. Severity of OSA or CSA was not significantly related to AF or > 10 PVC/h.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT01128816; URL: www.

CLINICALTRIALS

gov.

Atrial fibrillation onset before heart failure or vice versa: what is worst? A nationwide register study

AIMS

Atrial fibrillation (AF) and heart failure (HF) often coexist. However, whether AF onset before HF or vice versa is associated with the worst outcome remains unclear. A consensus of large studies can guide future research and preventive strategies to better target high-risk patients.

METHODS AND RESULTS

We included all Danish cases with the coexistence of AF and HF (2005-17) using nationwide registries. Patients were divided into three separate groups (i) AF before HF, (ii) HF before AF, or (iii) AF and HF diagnosed concurrently (±30 days). Adjusting landmark Cox analyses (index date was the time of the latter diagnosis of AF or HF) were used for evaluating the association of the three groups with a composite outcome of ischaemic stroke or death. Among a total of 49 042 patients included, 40% had AF before HF, 27% had HF before AF, and 33% had AF and HF diagnosed concurrently. The composite endpoint accrued more often in patients with HF before AF compared to the two other groups (<0.001), and this remained significant in the adjusted analyses with hazard ratios (95% confidence intervals) of 1.26 (1.22-1.30) compared to AF before HF. Finally, antihypertensive treatment, oral anticoagulants, amiodarone, statins, and AF ablation were associated with a lower hazard ratio of the composite endpoint (all < 0.001).

CONCLUSIONS

In this large Danish national cohort, diagnosis of HF before AF was associated with an increased absolute risk of death compared to AF before HF and AF and HF diagnosed concurrently. Antihypertensive treatment, oral anticoagulants, amiodarone, statins, and AF ablation may improve prognosis.

Incidence and Determinants of Spontaneous Cardioversion of Early Onset Symptomatic Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent chronic arrhythmia worldwide, and it is associated with significant morbidity and mortality, making it a considerable burden both to patients and the healthcare system. Nowadays, an early attempt to restore sinus rhythm in acute symptomatic AF through electrical or pharmacological cardioversion is the most common approach in the Emergency Department (ED). However, considering the high percentage of spontaneous cardioversion of paroxysmal AF reported by many studies, this approach may not be the ideal choice for all patients. In this manuscript we performed a review of the most relevant studies found in literature with the aim of identifying the main determinants of spontaneous cardioversion, focusing on those easy to detect in the ED. We have found that the most relevant predictors of spontaneous cardioversion are the absence of Heart Failure (HF), a small atrial size, recent-onset AF, rapid Atrial Fibrillatory Rate and the relationship between a previous AF episode and Heart Rate/Blood Pressure. A number of those are utilized, along with other easily determined parameters, in the recently developed "ReSinus" score which predicts the likelihood of AF spontaneous cardioversion. Such identification may help the physician decide whether immediate cardioversion is necessary, or whether to adopt a "watch-and-wait" strategy in the presence of spontaneous cardioversion determinants.