Relationship Between Endothelial Dysfunction and the Outcomes After Atrial Fibrillation Ablation

Background Endothelial dysfunction (ED) is associated with cardiovascular events in patients with atrial fibrillation (AF). However, the utility of ED as a prognostic marker after AF ablation supplementary to the CHA₂DS₂-VASc score is unclear. This study aimed to investigate the relationship between ED and 5-year cardiovascular events in patients undergoing AF ablation. Methods and Results We conducted a prospective cohort study of patients who underwent a first-time AF ablation and for whom the endothelial function was assessed by the peripheral vascular reactive hyperemia index (RHI) before ablation. We defined ED as an RHI of <2.1. Cardiovascular events included strokes, heart failure requiring hospitalization, arteriosclerotic disease requiring treatment, venous thromboses, and ventricular arrhythmias or sudden cardiac death. We compared the 5-year incidence of cardiovascular events after AF ablation between those with and without ED. Among the 1040 patients who were enrolled, 829 (79.7%) had ED, and the RHI value was found to be associated with the CHA₂DS₂-VASc score (P=0.004). The 5-year incidence of cardiovascular events was higher among patients with ED than those without ED (98 [11.8%] versus 13 [6.2%]; log-rank P=0.014). We found ED to be an independent predictor of cardiovascular events after AF ablation (hazard ratio [HR], 1.91 [95% CI, 1.04-3.50]; P=0.036) along with a CHA₂DS₂-VASc score of ≥2 (≥3 for women) (HR, 3.68 [95% CI, 1.89-7.15]; P<0.001). Conclusions The prevalence of ED among patients with AF was high. Assessing the endothelial function could enable the risk stratification of cardiovascular events after AF ablation.

Association of Atrial Fibrillation With Incidence of Extracranial Systemic Embolic Events: The ARIC Study

Background

Atrial fibrillation (AF) increases the risk of stroke and extracranial systemic embolic events (SEEs), but little is known about the magnitude of the association of AF with SEE.

Methods and Results

This analysis included 14 941 participants of the ARIC (Atherosclerosis Risk in Communities) study (mean age, 54.2±5.8, 55% women, 74% White) without AF at baseline (1987–1989) followed through 2017. AF was identified from study ECGs, hospital discharges, and death certificates, while SEEs were ascertained from hospital discharges. CHA₂DS₂‐VASc was calculated at the time of AF diagnosis. Cox regression was used to estimate associations of incident AF with SEE risk in the entire cohort, and between CHA₂DS₂‐VASc score and SEE risk in those with AF. Among eligible participants, 3114 participants developed AF and 270 had an SEE (59 events in AF). Incident AF was associated with increased risk of SEE (hazard ratio [HR], 3.58; 95% CI, 2.57–5.00), after adjusting for covariates. The association of incident AF with SEE was stronger in women (HR, 5.26; 95% CI, 3.28–8.44) than in men (HR, 2.68; 95% CI, 1.66–4.32). In those with AF, higher CHA₂DS₂‐VASc score was associated with increased SEE risk (HR per 1‐point increase, 1.24; 95% CI, 1.05–1.47).

Conclusions

AF is associated with more than a tripling of the risk of SEE, with a stronger association in women than in men. CHA₂DS₂‐VASc is associated with SEE risk in AF patients, highlighting the value of the score to predict adverse outcomes and guide treatment decisions in people with AF.

Atrial Cardiopathy in the Absence of Atrial Fibrillation Increases Risk of Ischemic Stroke, Incident Atrial Fibrillation, and Mortality and Improves Stroke Risk Prediction

Background Atrial fibrillation (AF) is a major, often undetected, cardiac cause of stroke. Markers of atrial cardiopathy, including left atrial enlargement (LAE) or excessive atrial ectopy (EAE) increase the risk of AF and have shown associations with stroke. We sought to determine whether these markers improve stroke risk prediction beyond traditional vascular risk factors (eg CHA₂DS₂-VASc score). Methods and Results Retrospective longitudinal cohort of 32 454 consecutive community-dwelling adults aged ≥65 years referred for outpatient echocardiogram or Holter in Ontario, Canada (2010-2017). Moderate-severe LAE was defined as men >47 mm and women >43 mm, and EAE was defined as >30 APBs per hour. Cause-specific competing risks Cox proportional hazards used to estimate risk of ischemic stroke (primary), incident AF, and death (secondary). C-statistics, incremental discrimination improvement and net reclassification were used to compare CHA₂DS₂-VASc with LAE and EAE to CHA₂DS₂-VASc alone. Each 10 mm increase in left atrial diameter increased 2- and 5-year adjusted cause-specific stroke hazard almost 2-fold (LAE: 2-year hazard ratio (HR), 1.72; P=0.007; 5-year HR, 1.87; P<0.0001), while EAE showed no significant associations with stroke (2-year HR, 1.00; P=0.99; 5-year HR, 1.08, P=0.70), adjusting for incident AF. Stroke risk estimation improved significantly at 2 (C-statistics=0.68-0.75, P=0.008) and 5 years (C-statistics=0.70-0.76, P=0.003) with LAE and EAE. Conclusions LAE was independently associated with an increased risk of ischemic stroke in the absence of AF and both LAE and EAE improved stroke risk prediction. These findings have implications for stroke risk stratification, AF screening, and stroke prevention before the onset of AF.

Risks of Bleeding and Stroke Based on CHA2DS2-VASc Scores in Japanese Patients With Atrial Fibrillation: A Large-Scale Observational Study Using Real-World Data

Background This large-scale observational study on negative events in a real-world setting investigated Japanese patients with atrial fibrillation who were not on anticoagulants. This study aims to evaluate the incidence of ischemic stroke and bleeding events (intracranial hemorrhage, gastrointestinal bleeding, others) based on CHA2DS2-VASc scores in Japanese patients with atrial fibrillation who were not anticoagulated. Methods and Results We used health checkups and insurance claim data from a Japanese insurance organization. Altogether, 9733 atrial fibrillation patients were not prescribed anticoagulation during their follow-up periods. Patients' risk levels were defined by their CHA2DS2-VASc scores (range 0-≥3): Men with scores of 0, 1, or ≥2 and women with scores of 1, 2, or ≥3 were considered at low, intermediate, or high risk, respectively. Cox proportional hazards model was used to assess the association between the CHA2DS2-VASc-determined risk and the incidence of ischemic stroke and intracranial, gastrointestinal, and other bleeding. The mean 2.5-year follow-up revealed 143 ischemic strokes and 332 bleeding events. Annual event rates were 0.58% for ischemic stroke and 1.17% for total bleeding events. Annual incidence of ischemic stroke increased with elevated predicted risks based on CHA2DS2-VASc scores: 0.18% for low-risk, 0.44% intermediate-risk, and 1.29% high-risk groups (P<0.001 for trend). Annual incidences of total bleeding also increased with elevated predicted risks: 0.51% for low-risk, 1.28% intermediate-risk, and 2.02% high-risk groups (P<0.001 for trend). Conclusions Risks of ischemic stroke and bleeding events were high, particularly among those with high CHA2DS2-VASc scores.

Risk Stratification Using the CHA2DS2-VASc Score in Takotsubo Syndrome: Data From the Takotsubo Italian Network

Background

The CHA₂DS₂‐VASc score predicts stroke in patients with atrial fibrillation and has been reported to have a prognostic role even in acute coronary syndrome patients. The Takotsubo syndrome is a condition that mimics acute coronary syndrome and may present several complications including stroke. We sought to assess the ability of CHA₂DS₂‐VASc score to predict adverse events in Takotsubo syndrome patients.

Methods and Results

Overall, 371 Takotsubo syndrome patients were enrolled in a prospective registry. Patients were divided into 3 groups according to the CHA₂DS₂‐VASc score: Group A (≤1), B (2–3), and C (≥4). The median CHA₂DS₂‐VASc score was 3 (interquartile range: 2–4). Overall, 9%, 42%, and 49% were included in Group A, B, and C, respectively. Follow‐up length was 26±20 months. The mortality rate was 6%, 7%, and 17% in Group A, B, and C, respectively (P=0.011). The stroke rate was 3% and not different among the 3 groups. Estimated major adverse cardiac and cerebrovascular events (the composite of death, myocardial infarction, and stroke) rates in the 3 groups were 6%, 9%, and 17% in Group A, B, and C, respectively (P=0.033). The CHA₂DS₂‐VASc score resulted as a predictor of major adverse cardiac and cerebrovascular events (odds ratio 2.1, 95% confidence interval, 1.2–3.6; P=0.01) and all‐cause mortality (odds ratio 1.5, 95% confidence interval, 1.2–1.9; P=0.001).

Conclusions

In Takotsubo syndrome, the CHA₂DS₂‐VASc score allows prediction of cardiovascular events and mortality at long‐term follow‐up.

Is an Oral Anticoagulant Necessary for Young Atrial Fibrillation Patients With a CHA2DS2-VASc Score of 1 (Men) or 2 (Women)?

Background

Recent studies demonstrated that oral anticoagulants (OACs) should be considered for patients with atrial fibrillation and 1 risk factor in addition to sex. Because age is an important determinant of ischemic stroke, the strategy for stroke prevention may be different for these patients in different age strata. The aim of this study was to investigate whether OACs should be considered for patients aged 20 to 49 years with atrial fibrillation and a CHA₂DS₂‐VASc score of 1 (men) or 2 (women).

Methods and Results

Using the Taiwan National Health Insurance Research Database, 7374 male patients with atrial fibrillation and a CHA₂DS₂‐VASc score of 1 and 4461 female patients with atrial fibrillation and a CHA₂DS₂‐VASc score of 2 and all without antithrombotic therapies were identified and stratified into 3 groups by age. The threshold for the initiation of OACs for stroke prevention was set at a stroke rate of 1.7% per year for warfarin and 0.9% per year for non–vitamin K antagonist OACs. Among male patients aged 20 to 49 years with a CHA₂DS₂‐VASc score of 1, the risk of ischemic stroke was 1.30% per year and ranged from 0.94% per year for those with hypertension to 1.71% for those with congestive heart failure. Among female patients aged 20 to 49 years with a CHA₂DS₂‐VASc score of 2, the risk of ischemic stroke was 1.40% per year and ranged from 1.11% per year for those with hypertension to 1.67% for those with congestive heart failure.

Conclusions

For atrial fibrillation patients aged 20 to 49 years with 1 risk factor in addition to sex, non–vitamin K antagonist OACs should be considered for stroke prevention to minimize the risk of a potentially fatal or disabling event.

The CHA2DS2-VASc score as a predictor of high mortality in hospitalized heart failure patients

Aims

Atrial fibrillation (AF) is common in patients with heart failure (HF). CHA₂DS₂‐VASc score was originally employed as a risk assessment tool for stroke in patients with AF; however, it has recently been used to predict not only stroke but also various cardiovascular diseases beyond the original AF field. We aimed to verify the CHA₂DS₂‐VASc score as a risk assessment tool to predict mortality in patients with HF.

Methods and Results

Consecutive 1011 patients admitted for treatment of HF were divided into three groups based on their CHA₂DS₂‐VASc scores: score 1–3 group (n = 317), score 4–6 group (n = 549) and score 7–9 group (n = 145). Of the 1011 HF patients, 387 (38.3%) had AF. We compared patient characteristics among the three groups and prospectively followed for all‐cause mortality. Although left ventricular ejection fraction was similar among all three groups, all‐cause mortality was higher in the score 4–6 group and score 7–9 group than in the score 1–3 group (37.9 and 29.3% vs. 15.1%, log‐rank P < 0.001). In the multivariable Cox proportional hazard analysis, the CHA₂DS₂‐VASc score 7–9 was an independent predictor of all‐cause mortality (all HF patients: hazard ratio (HR) 1.822, P = 0.011; HF patients with AF: HR 1.951, P = 0.031; HF patients without AF: HR 2.215, P = 0.033).

Conclusions

The CHA₂DS₂‐VASc score was an independent predictor of all‐cause mortality in HF patients with or without AF. This comprehensive risk assessment score may help identify HF patients who are at high risk for mortality in HF patient.