Neurofilament Light Chain and Risk of Stroke in Patients With Atrial Fibrillation.

BACKGROUND: Biomarkers reflecting brain injury are not routinely used in risk assessment of stroke in atrial fibrillation (AF). Neurofilament light chain (NFL) is a novel biomarker released into blood after cerebral insults. We investigated the association between plasma concentrations of NFL, other biomarkers, and risk of stroke and death in patients with AF not receiving oral anticoagulation. METHODS: For this observational study, baseline plasma samples were available from 3077 patients with AF randomized to aspirin in ACTIVE A (Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events; 2003 to 2008) and AVERROES (Apixaban Versus Acetylsalicylic Acid [ASA] to Prevent Stroke in Atrial Fibrillation Patients Who Have Failed or Are Unsuitable for Vitamin K Antagonist Treatment; 2007 to 2009). Median follow-up was 1.5 years. NFL was analyzed with a Single Molecule Array (Simoa). Associations with outcomes (total stroke or systemic embolism, ischemic stroke, cardiovascular death, and all-cause death) were explored with Cox regression models. RESULTS: In the combined cohort, the median NFL level was 16.9 ng/L (interquartile range, 11.1-26.5 ng/L), the median age was 71 years, 58% were men, and 13% had a history of previous stroke. NFL was associated with older age, higher creatinine, lower body mass index, previous stroke, female sex, and diabetes but not cardiac rhythm. Higher NFL was associated with a higher risk of stroke or systemic embolism (n=206) independently of clinical characteristics (hazard ratio, 1.27 [95% CI, 1.10-1.46] per doubling of NFL) and other biomarkers (hazard ratio, 1.18 [95% CI, 1.01-1.37]) and including in patients without previous stroke (hazard ratio, 1.23 [95% CI, 1.02-1.48]). NFL was also independently associated with cardiovascular (n=219) and all-cause (n=311) death. The C index for stroke using only NFL was 0.642, on par with the currently used clinical risk scores. Addition of information on NFL improved discrimination in a model also including clinical information, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and high-sensitivity cardiac troponin T, yielding a C index of 0.727. CONCLUSIONS: NFL reflects overt and covert episodes of cerebral ischemia and improves risk assessment of stroke and death in patients with AF without oral anticoagulation, including in patients without previous stroke. The combination of NFL with information on age, history of stroke, and other biomarkers should be explored as a future avenue for stroke risk assessments in patients with AF.

Randomized Invitation to Systematic NT-proBNP and ECG Screening in 75-Year Olds to Detect Atrial Fibrillation -STROKESTOP II.

Background: Guidelines have suggested screening for atrial fibrillation to enable early treatment and avoid downstream negative clinical events. We aimed to determine if atrial fibrillation screening potentially enhanced by NT-proBNP would reduce stroke or systemic embolism incidence as compared to in a control group and to determine if it was safe for those with low NT-proBNP concentrations to forfeit prolonged screening. Methods: In this randomized controlled trial all 75/76-year-old individuals in Stockholm Region, Sweden were randomized 1:1 to be invited to screening or serve as a control group. NT-proBNP concentration were measured and a single-lead-ECG registered only once if NT-proBNP<125ng/L, whereas if NT-proBNP≥125 ng/L participants underwent prolonged screening, recording single-lead ECGs four times daily for two weeks. If atrial fibrillation was detected, treatment was initiated. Baseline and outcome data were collected from Swedish National Registries. Results: In total 28,712 individuals were randomized, after exclusion of death and emigration 13,905 remained in the intervention group, 13,884 in the control group. Participation rate in the intervention group was 49.2% (6,843/13,905). Participants in the high NT-proBNP group (NT-proBNP≥125 ng/L) without prior atrial fibrillation constituted 60% of the total and underwent prolonged screening. New AF was detected in 2.4% (165/6,843) in the intervention group. There was no difference in AF prevalence or oral anticoagulant treatment between the intervention and the control group after five years follow-up. After a median of 5.1 years (IQR 5.0-5.8) there was no difference in the primary outcome of stroke or systemic embolism between the intervention group and the control group, HR: 0.96 (95% CI 0.86-1.06). The low NT-proBNP-group had significantly fewer strokes or systemic emboli than the control group, HR: 0.59 (95% CI 0.46-0.74), p<0.001. In the high NT-proBNP group the risk of stroke or systemic embolism was higher compared to the low NT-proBNP group, HR: 1.57 (95% CI 1.22-2.02), p=0.001. Conclusions: In this population-based screening trial for atrial fibrillation using NT-proBNP for screening enhancement, there was no difference in risk of stroke or systemic embolism for the intervention group compared to controls. Participation was moderate. The use of NT-proBNP for screening enhancement was safe in identifying low-risk participants. Clinical Trial Registration: www.clinicaltrials.gov; NCT02743416.

Direct Oral Anticoagulants Versus Warfarin Across the Spectrum of Kidney Function: Patient-Level Network Meta-Analyses From COMBINE AF.

BACKGROUND: There is uncertainty surrounding the use of direct oral anticoagulants (DOACs) in patients with kidney dysfunction. METHODS: Using the COMBINE AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation) database (data from RE-LY [Randomized Evaluation of Long-term Anticoagulation Therapy], ROCKET AF [Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation], ARISTOTLE [Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation], and ENGAGE AF-TIMI 48 [Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48]), we performed an individual patient-level network meta-analysis to evaluate the safety and efficacy of DOACs versus warfarin across continuous creatinine clearance (CrCl). A multivariable Cox model including treatment-by-CrCl interaction with random effects was fitted to estimate hazard ratios for paired treatment strategies (standard-dose DOAC, lower-dose DOAC, and warfarin). Outcomes included stroke and systemic embolism (S/SE), major bleeding, intracranial hemorrhage (ICH), and death. RESULTS: Among 71 683 patients (mean age, 70.6±9.4 years; 37.3% female; median follow-up, 23.1 months), the mean CrCl was 75.5±30.5 mL/min. The incidence of S/SE, major bleeding, ICH, and death increased significantly with worsening kidney function. Across continuous CrCl values down to 25 mL/min, the hazard of major bleeding did not change for patients randomized to standard-dose DOACs compared with those randomized to warfarin (Pinteraction=0.61). Compared with warfarin, standard-dose DOAC use resulted in a significantly lower hazard of ICH at CrCl values <122 mL/min, with a trend for increased safety with DOAC as CrCl decreased (6.2% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.08). Compared with warfarin, standard-dose DOAC use resulted in a significantly lower hazard of S/SE with CrCl <87 mL/min, with a significant treatment-by-CrCl effect (4.8% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.01). The hazard of death was significantly lower with standard-dose DOACs for patients with CrCl <77 mL/min, with a trend toward increasing benefit with lower CrCl (2.1% decrease in hazard ratio per 10-mL/min decrease in CrCl; Pinteraction=0.08). Use of lower-dose rather than standard-dose DOACs was not associated with a significant difference in incident bleeding or ICH in patients with reduced kidney function but was associated with a higher incidence4 of death and S/SE. CONCLUSIONS: Standard-dose DOACs are safer and more effective than warfarin down to a CrCl of at least 25 mL/min. Lower-dose DOACs do not significantly lower the incidence of bleeding or ICH compared with standard-dose DOACs but are associated with a higher incidence of S/SE and death. These findings support the use of standard-dose DOACs over warfarin in patients with kidney dysfunction.

Longer and better lives for patients with atrial fibrillation: the 9th AFNET/EHRA consensus conference.

AIMS: Recent trial data demonstrate beneficial effects of active rhythm management in patients with atrial fibrillation (AF) and support the concept that a low arrhythmia burden is associated with a low risk of AF-related complications. The aim of this document is to summarize the key outcomes of the 9th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). METHODS AND RESULTS: Eighty-three international experts met in Münster for 2 days in September 2023. Key findings are as follows: (i) Active rhythm management should be part of the default initial treatment for all suitable patients with AF. (ii) Patients with device-detected AF have a low burden of AF and a low risk of stroke. Anticoagulation prevents some strokes and also increases major but non-lethal bleeding. (iii) More research is needed to improve stroke risk prediction in patients with AF, especially in those with a low AF burden. Biomolecules, genetics, and imaging can support this. (iv) The presence of AF should trigger systematic workup and comprehensive treatment of concomitant cardiovascular conditions. (v) Machine learning algorithms have been used to improve detection or likely development of AF. Cooperation between clinicians and data scientists is needed to leverage the potential of data science applications for patients with AF. CONCLUSIONS: Patients with AF and a low arrhythmia burden have a lower risk of stroke and other cardiovascular events than those with a high arrhythmia burden. Combining active rhythm control, anticoagulation, rate control, and therapy of concomitant cardiovascular conditions can improve the lives of patients with AF.

Bone morphogenetic protein 10: a novel risk marker of ischaemic stroke in patients with atrial fibrillation.

AIMS: Biomarkers specifically related to atrial tissue may increase the understanding of the pathophysiology of atrial fibrillation (AF) and further improve risk prediction in this setting. Bone morphogenetic protein 10 (BMP10) is a protein expressed in the atrial myocardium. We evaluated the association between BMP10 and the risk of ischaemic stroke and other cardiovascular events in large cohorts of patients with AF, treated with and without oral anticoagulation (OAC). METHODS AND RESULTS: BMP10 was measured in plasma samples collected at randomisation in patients with AF without OAC in the ACTIVE A and AVERROES trials (n = 2974), and with OAC in the ARISTOTLE trial (n = 13 079). BMP10 was analysed with a prototype Elecsys immunoassay. Associations with outcomes were evaluated by Cox-regression models adjusted for clinical characteristics, kidney function, and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Median concentrations of BMP10 were 2.47 and 2.44 ng/mL, in the non-OAC and OAC cohort, respectively. Increasing BMP10 was associated with lower body mass index, older age, female sex, kidney dysfunction, and AF rhythm. BMP10 was consistently associated with ischaemic stroke. In the non-OAC cohort, BMP10 increased the concordance index of the multivariable model from 0.713 to 0.733 (P = 0.004) and in the OAC cohort from 0.673 to 0.694 (P < 0.001). Additionally, BMP10 maintained a significant prognostic value after additionally adjusting for NT-proBNP. BMP10 was not independently associated with bleeding or with death. CONCLUSION: The novel atrial biomarker BMP10 was independently associated with ischaemic stroke in patients with AF irrespective of OAC treatment. BMP10 seems to be more specifically related to the risk of ischaemic stroke in AF. ONE-SENTENCE SUMMARY: In this study, BMP10 may be a novel specific biomarker of ischaemic stroke in patients with atrial fibrillation, irrespective of oral anticoagulation.

Outcomes of patients with atrial fibrillation and ischemic stroke while on oral anticoagulation.

AIMS: The prognosis of patients with atrial fibrillation (AF) and ischemic stroke while taking oral anticoagulation is poorly understood. This study aimed to characterize the outcomes of patients following a stroke event while on oral anticoagulation. METHODS AND RESULTS: Individual participant data from five pivotal randomized trials of antithrombotic therapy in AF were used to assess the outcomes of patients with a post-randomization ischemic stroke while on study medication (warfarin, standard-, or lower-dose direct oral anticoagulant regimen) during trial follow-up. The primary outcome was recurrent ischemic stroke after the first post-randomization ischemic stroke. The primary analysis included 1163 patients with a first post-randomization ischemic stroke while on study medication (median age 73 years, 39.3% female, 35.4% history of stroke before trial enrollment). During a median continued follow-up of 337 days, 74 patients had a recurrent ischemic stroke [cumulative incidence at 1 year: 7.0%, 95% confidence interval (CI) 5.2%-8.7%]. The cumulative incidence of mortality at 3 months after stroke was 12.4% (95% CI 10.5%-14.4%). Consistent results for the incidence of recurrent ischemic stroke at 1 year were obtained in an analysis accounting for the competing risk of death (6.2%, 95% CI 4.8%-7.9%) and in a landmark analysis excluding the first 2 weeks after the index stroke and only including patients without permanent study drug discontinuation since then (6.8%, 95% CI 4.6%-8.9%). CONCLUSION: Patients with AF and ischemic stroke while on oral anticoagulation are at increased risk of recurrent ischemic stroke and death. These patients currently have an unmet medical need.

Early Versus Delayed Non-Vitamin K Antagonist Oral Anticoagulant Therapy After Acute Ischemic Stroke in Atrial Fibrillation (TIMING): A Registry-Based Randomized Controlled Noninferiority Study.

BACKGROUND: There are no evidence-based recommendations on the optimal time point to initiate non-vitamin K antagonist oral anticoagulants (NOACs) after acute ischemic stroke in patients with atrial fibrillation. We aimed to investigate the efficacy and safety of early versus delayed initiation of NOAC in these patients. METHODS: TIMING (Timing of Oral Anticoagulant Therapy in Acute Ischemic Stroke With Atrial Fibrillation) was a registry-based, randomized, noninferiority, open-label, blinded end-point study at 34 stroke units using the Swedish Stroke Register for enrollment and follow-up. Within 72 hours from stroke onset, patients were randomized to early (≤4 days) or delayed (5-10 days) NOAC initiation, with choice of NOAC at the investigators' discretion. The primary outcome was the composite of recurrent ischemic stroke, symptomatic intracerebral hemorrhage, or all-cause mortality at 90 days. The prespecified noninferiority margin was 3%. Secondary outcomes included the individual components of the primary outcome. RESULTS: Between April 2, 2017, and December 30, 2020, 888 patients were randomized to either early (n=450) or delayed (n=438) initiation of NOAC. No patient was lost to 90-day follow-up. Mean age was 78.3 years (SD, 9.9 years); 46.2% were women; 49.1% had previously known atrial fibrillation; and 17.5% prior stroke. The primary outcome occurred in 31 patients (6.89%) assigned to early initiation and in 38 patients (8.68%) assigned to delayed NOAC initiation (absolute risk difference, -1.79% [95% CI, -5.31% to 1.74%]; Pnoninferiority=0.004). Ischemic stroke rates were 3.11% and 4.57% (risk difference, -1.46% [95% CI, -3.98% to 1.07%]) and all-cause mortality rates were 4.67% and 5.71% (risk difference, -1.04% [95% CI, -3.96% to 1.88%]) in the early and delayed groups, respectively. No patient in either group experienced symptomatic intracerebral hemorrhage. CONCLUSIONS: Early initiation was noninferior to delayed start of NOAC after acute ischemic stroke in patients with atrial fibrillation. Numerically lower rates of ischemic stroke and death and the absence of symptomatic intracerebral hemorrhages implied that the early start of NOAC was safe and should be considered for acute secondary stroke prevention in patients eligible for NOAC treatment. REGISTRATION: URL: http://www. CLINICALTRIALS: gov; Unique identifier: NCT02961348.

Direct Oral Anticoagulants Versus Warfarin in Patients With Atrial Fibrillation: Patient-Level Network Meta-Analyses of Randomized Clinical Trials With Interaction Testing by Age and Sex.

BACKGROUND: Direct oral anticoagulants (DOACs) are preferred over warfarin for stroke prevention in atrial fibrillation. Meta-analyses using individual patient data offer substantial advantages over study-level data. METHODS: We used individual patient data from the COMBINE AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation) database, which includes all patients randomized in the 4 pivotal trials of DOACs versus warfarin in atrial fibrillation (RE-LY [Randomized Evaluation of Long-Term Anticoagulation Therapy], ROCKET AF [Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation], ARISTOTLE [Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation], and ENGAGE AF-TIMI 48 [Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48]), to perform network meta-analyses using a stratified Cox model with random effects comparing standard-dose DOAC, lower-dose DOAC, and warfarin. Hazard ratios (HRs [95% CIs]) were calculated for efficacy and safety outcomes. Covariate-by-treatment interaction was estimated for categorical covariates and for age as a continuous covariate, stratified by sex. RESULTS: A total of 71 683 patients were included (29 362 on standard-dose DOAC, 13 049 on lower-dose DOAC, and 29 272 on warfarin). Compared with warfarin, standard-dose DOACs were associated with a significantly lower hazard of stroke or systemic embolism (883/29 312 [3.01%] versus 1080/29 229 [3.69%]; HR, 0.81 [95% CI, 0.74-0.89]), death (2276/29 312 [7.76%] versus 2460/29 229 [8.42%]; HR, 0.92 [95% CI, 0.87-0.97]), and intracranial bleeding (184/29 270 [0.63%] versus 409/29 187 [1.40%]; HR, 0.45 [95% CI, 0.37-0.56]), but no statistically different hazard of major bleeding (1479/29 270 [5.05%] versus 1733/29 187 [5.94%]; HR, 0.86 [95% CI, 0.74-1.01]), whereas lower-dose DOACs were associated with no statistically different hazard of stroke or systemic embolism (531/13 049 [3.96%] versus 1080/29 229 [3.69%]; HR, 1.06 [95% CI, 0.95-1.19]) but a lower hazard of intracranial bleeding (55/12 985 [0.42%] versus 409/29 187 [1.40%]; HR, 0.28 [95% CI, 0.21-0.37]), death (1082/13 049 [8.29%] versus 2460/29 229 [8.42%]; HR, 0.90 [95% CI, 0.83-0.97]), and major bleeding (564/12 985 [4.34%] versus 1733/29 187 [5.94%]; HR, 0.63 [95% CI, 0.45-0.88]). Treatment effects for standard- and lower-dose DOACs versus warfarin were consistent across age and sex for stroke or systemic embolism and death, whereas standard-dose DOACs were favored in patients with no history of vitamin K antagonist use (P=0.01) and lower creatinine clearance (P=0.09). For major bleeding, standard-dose DOACs were favored in patients with lower body weight (P=0.02). In the continuous covariate analysis, younger patients derived greater benefits from standard-dose (interaction P=0.02) and lower-dose DOACs (interaction P=0.01) versus warfarin. CONCLUSIONS: Compared with warfarin, DOACs have more favorable efficacy and safety profiles among patients with atrial fibrillation.

Individual net clinical outcome with oral anticoagulation in atrial fibrillation using the ABC-AF risk scores.

BACKGROUND: Decisions on stroke prevention strategies in patients with atrial fibrillation (AF) depend on the perceived risks of stroke and bleeding with different antithrombotic treatment strategies. The study objectives were to evaluate net clinical outcome with oral anticoagulation (OAC) for the individual patient with AF and to identify clinically relevant thresholds for OAC treatment. METHODS: Patients with AF receiving OAC treatment in the randomized ARISTOTLE and RE-LY trials, with available biomarkers for calculation of ABC-AF scores at baseline, were included (n = 23,121). Observed 1-year risk on OAC was compared with predicted 1-year risk if the same patients would not have received OAC using the ABC-AF scores calibrated for aspirin. Net clinical outcome was defined as the sum of stroke and major bleeding risks. RESULTS: The ratio between the 1-year incidence of major bleeding and stroke/systemic embolism events ranged from 1.4 to 10.6 according to different ABC-AF risk profiles. Net clinical outcome analyses showed that in patients with an ABC-AF-stroke risk >1% per year on OAC (>3% without OAC), treatment with OAC consistently provides larger net clinical benefit than no-OAC treatment. In patients with an ABC-AF-stroke risk <1.0% per year on OAC (<3% without OAC) an individualized balancing of risks regarding OAC or no-OAC treatment is needed. CONCLUSIONS: In patients with AF, the ABC-AF risk scores allow an individual and continuous estimate of the balance between benefits and risks with OAC treatment. This precision medicine tool therefore seems useful as decision support and visualizes the net clinical benefit or harm with OAC treatment (http://www.abc-score.com/abcaf/). CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00412984 (ARISTOTLE) and NCT00262600 (RE-LY).

Heart rate and death and hospitalization for heart failure in patients with persistent or permanent atrial fibrillation: Insights from the ARISTOTLE trial.

Rate control is fundamental in the treatment of patients with atrial fibrillation (AF). The independent association of heart rate with outcomes and range of heart rate associated with best outcomes remains uncertain. We assessed the relationship between heart rate and clinical outcomes in patients with persistent or permanent AF enrolled in the randomized, double-blind ARISTOTLE trial. In patients with persistent or permanent AF, a faster heart rate is associated with a modest, but statistically significant increase in death and heart failure hospitalizations. TRIAL REGISTRATION: ClinicalTrials.gov (NCT00412984).

Plasma angiopoietin-2 and its association with heart failure in patients with atrial fibrillation.

AIMS: Several biomarkers are associated with clinical outcomes in patients with atrial fibrillation (AF), but a causal relationship has not been established. This study aimed to evaluate angiopoietin-2, a novel candidate biomarker of endothelial inflammation and vascular remodelling, in patients with AF. METHODS AND RESULTS: Angiopoietin-2 was measured in plasma obtained from patients with AF treated with aspirin monotherapy (exploration cohort, n = 2987) or with oral anticoagulation (validation cohort, n = 13 079). Regression models were built to assess the associations between angiopoietin-2, clinical characteristics, and outcomes. In both cohorts, plasma angiopoietin-2 was independently associated with AF on the baseline electrocardiogram and persistent/permanent AF, age, history of heart failure, female sex, tobacco use/smoking, body mass index, renal dysfunction, diabetes, and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Angiopoietin-2 was independently associated with subsequent hospitalization for heart failure after adjusting for age, creatinine, and clinical characteristics in the exploration cohort [c-index 0.79, 95% confidence interval (CI) 0.75-0.82; third vs. first quartile, hazard ratio (HR) 1.74, 95% CI 1.26-2.41] and in the validation cohort (c-index 0.76, 95% CI 0.74-0.78; HR 1.58, 95% CI 1.37-1.82). In both cohorts, the association persisted when also adjusting for NT-proBNP (P ≤ 0.001). In full multivariable models also adjusted for NT-proBNP, angiopoietin-2 did not show statistically significant associations with ischaemic stroke, cardiovascular and all-cause death, or major bleeding that were consistent across the two cohorts. CONCLUSIONS: In patients with AF, plasma levels of angiopoietin-2 were independently associated with subsequent hospitalization for heart failure and provided incremental prognostic value to clinical risk factors and NT-proBNP.

Biomarker-Based Risk Prediction With the ABC-AF Scores in Patients With Atrial Fibrillation Not Receiving Oral Anticoagulation.

BACKGROUND: The novel ABC (Age, Biomarkers, Clinical History) scores outperform traditional risk scores for stroke, major bleeding, and death in patients with atrial fibrillation (AF) receiving oral anticoagulation. To refine their utility, the ABC-AF scores needed to be validated in patients not receiving oral anticoagulation. METHODS: We measured plasma levels of the ABC biomarkers (N-terminal pro-B-type natriuretic peptide, cardiac troponin-T, and growth-differentiation factor 15) to apply the previously developed ABC-AF scores in patients with AF receiving aspirin (n=3195) or aspirin and clopidogrel (n=1110) in 2 large clinical trials. Calibration was assessed by comparing estimated with observed 1-year risks. Cox regression models were used for recalibration. Discrimination was evaluated separately for the aspirin-only and the overall cohort (n=4305). RESULTS: The ABC-AF-stroke score yielded a c-index of 0.70 (95% CI, 0.67-0.73) in both cohorts. The ABC-AF-bleeding score had a c-index of 0.76 (95% CI, 0.71-0.81) in the aspirin-only cohort and 0.73 (95% CI, 0.69-0.77) overall. Both scores were superior to risk scores recommended by current guidelines. The ABC-AF-death score yielded a c-index of 0.78 (95% CI, 0.76-0.80) overall. Calibrated in patients receiving oral anticoagulation, the ABC-AF-stroke score underestimated and the ABC-AF-bleeding score overestimated the risk of events in both cohorts. These scores were recalibrated for prediction of absolute event rates in the absence of oral anticoagulation. CONCLUSIONS: The biomarker-based ABC-AF scores showed better discrimination than traditional risk scores and were recalibrated for precise risk estimation in patients not receiving oral anticoagulation. They can now provide improved decision support on treatment of an individual patient with AF.

Apixaban or Vitamin K Antagonists and Aspirin or Placebo According to Kidney Function in Patients With Atrial Fibrillation After Acute Coronary Syndrome or Percutaneous Coronary Intervention: Insights From the AUGUSTUS Trial.

BACKGROUND: In the AUGUSTUS trial (An Open-Label, 2×2 Factorial, Randomized Controlled, Clinical Trial to Evaluate the Safety of Apixaban Versus Vitamin K Antagonist and Aspirin Versus Aspirin Placebo in Patients With Atrial Fibrillation and Acute Coronary Syndrome or Percutaneous Coronary Intervention), apixaban resulted in less bleeding and fewer hospitalizations than vitamin K antagonists, and aspirin caused more bleeding than placebo in patients with atrial fibrillation and acute coronary syndrome or percutaneous coronary intervention treated with a P2Y12 inhibitor. We evaluated the risk-benefit balance of antithrombotic therapy according to kidney function. METHODS: In 4456 patients, the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula was used to calculate baseline estimated glomerular filtration rate (eGFR). The effect of apixaban versus vitamin K antagonists and aspirin versus placebo was assessed across kidney function categories by using Cox models. The primary outcome was International Society on Thrombosis and Haemostasis major or clinically relevant nonmajor bleeding. Secondary outcomes included death or hospitalization and ischemic events (death, stroke, myocardial infarction, stent thrombosis [definite or probable], or urgent revascularization). Creatinine clearance <30 mL/min was an exclusion criterion in the AUGUSTUS trial. RESULTS: Overall, 30%, 52%, and 19% had an eGFR of >80, >50 to 80, and 30 to 50 mL·min-1·1.73 m-2, respectively. At the 6-month follow-up, a total of 543 primary outcomes of bleeding, 1125 death or hospitalizations, and 282 ischemic events occurred. Compared with vitamin K antagonists, patients assigned apixaban had lower rates for all 3 outcomes across most eGFR categories without significant interaction. The absolute risk reduction with apixaban was most pronounced in those with an eGFR of 30 to 50 mL·min-1·1.73 m-2 for bleeding events with rates of 13.1% versus 21.3% (hazard ratio, 0.59; 95% CI, 0.41-0.84). Patients assigned aspirin had a higher risk of bleeding in all eGFR categories with an even greater increase among those with eGFR >80 mL·min-1·1.73 m-2: 16.6% versus 5.6% (hazard ratio, 3.22; 95% CI, 2.19-4.74; P for interaction=0.007). The risk of death or hospitalization and ischemic events were comparable to aspirin and placebo across eGFR categories with hazard ratios ranging from 0.97 (95% CI, 0.76-1.23) to 1.28 (95% CI, 1.02-1.59) and from 0.75 (95% CI, 0.48-1.17) to 1.34 (95% CI, 0.81-2.22), respectively. CONCLUSIONS: The safety and efficacy of apixaban was consistent irrespective of kidney function, compared with warfarin, and in accordance with the overall trial results. The risk of bleeding with aspirin was consistently higher across all kidney function categories. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02415400.

Antithrombotic Therapy after Acute Coronary Syndrome or PCI in Atrial Fibrillation.

BACKGROUND: Appropriate antithrombotic regimens for patients with atrial fibrillation who have an acute coronary syndrome or have undergone percutaneous coronary intervention (PCI) are unclear. METHODS: In an international trial with a two-by-two factorial design, we randomly assigned patients with atrial fibrillation who had an acute coronary syndrome or had undergone PCI and were planning to take a P2Y12 inhibitor to receive apixaban or a vitamin K antagonist and to receive aspirin or matching placebo for 6 months. The primary outcome was major or clinically relevant nonmajor bleeding. Secondary outcomes included death or hospitalization and a composite of ischemic events. RESULTS: Enrollment included 4614 patients from 33 countries. There were no significant interactions between the two randomization factors on the primary or secondary outcomes. Major or clinically relevant nonmajor bleeding was noted in 10.5% of the patients receiving apixaban, as compared with 14.7% of those receiving a vitamin K antagonist (hazard ratio, 0.69; 95% confidence interval [CI], 0.58 to 0.81; P<0.001 for both noninferiority and superiority), and in 16.1% of the patients receiving aspirin, as compared with 9.0% of those receiving placebo (hazard ratio, 1.89; 95% CI, 1.59 to 2.24; P<0.001). Patients in the apixaban group had a lower incidence of death or hospitalization than those in the vitamin K antagonist group (23.5% vs. 27.4%; hazard ratio, 0.83; 95% CI, 0.74 to 0.93; P = 0.002) and a similar incidence of ischemic events. Patients in the aspirin group had an incidence of death or hospitalization and of ischemic events that was similar to that in the placebo group. CONCLUSIONS: In patients with atrial fibrillation and a recent acute coronary syndrome or PCI treated with a P2Y12 inhibitor, an antithrombotic regimen that included apixaban, without aspirin, resulted in less bleeding and fewer hospitalizations without significant differences in the incidence of ischemic events than regimens that included a vitamin K antagonist, aspirin, or both. (Funded by Bristol-Myers Squibb and Pfizer; AUGUSTUS ClinicalTrials.gov number, NCT02415400.).

Biomarkers and heart failure events in patients with atrial fibrillation in the ARISTOTLE trial evaluated by a multi-state model.

BACKGROUND: Atrial fibrillation (AF) and heart failure (HF) often coexist. We investigated the prognostic impact of biomarkers on the development of HF and death in patients with AF and different left ventricular systolic function considering the influence of competing events. METHODS: The study included 11,818 patients with AF from the ARISTOTLE trial who at entry had information on history of HF, an estimate of left ventricular function and plasma samples for determination of biomarkers representing cardiorenal dysfunction (NT-proBNP, troponin T, cystatin C) and inflammation (GDF-15, IL-6, CRP). Patients were categorized into: (I) HF with reduced ejection fraction (HFrEF, n = 2,048), (II) HF with preserved ejection fraction (HFpEF, n = 2,520), and (III) No HF (n = 7,250). Biomarker associations with HF hospitalization and death were analyzed using a multi-state model accounting also for repeated events. RESULTS: Baseline levels of NT-proBNP, troponin T, cystatin C, GDF-15, IL-6, and CRP were highest in HFrEF and lowest in No HF. During median 1.9 years follow-up, 546 patients were hospitalized at least once for HF and 819 died. Higher levels of all investigated biomarkers were associated with both outcomes (all P< .0001), with highest event rates in HFrEF and lowest in No HF. The associations remained after adjustments and were more pronounced for first than for recurrent events. CONCLUSIONS: In anticoagulated patients with AF, biomarkers indicating cardiorenal dysfunction and inflammation improve the identification of patients at risk of developing HF or worsening of already existing HF. These biomarkers might be useful for targeting novel HF therapies in patients with AF.

Apixaban Versus Warfarin in Patients With Atrial Fibrillation and Advanced Chronic Kidney Disease.

BACKGROUND: Compared with the general population, patients with advanced chronic kidney disease have a >10-fold higher burden of atrial fibrillation. Limited data are available guiding the use of nonvitamin K antagonist oral anticoagulants in this population. METHODS: We compared the safety of apixaban with warfarin in 269 patients with atrial fibrillation and advanced chronic kidney disease (defined as creatinine clearance [CrCl] 25 to 30 mL/min) enrolled in the ARISTOTLE trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation). Cox proportional models were used to estimate hazard ratios for major bleeding and major or clinically relevant nonmajor bleeding. We characterized the pharmacokinetic profile of apixaban by assessing differences in exposure using nonlinear mixed effects models. RESULTS: Among patients with CrCl 25 to 30 mL/min, apixaban caused less major bleeding (hazard ratio, 0.34 [95% CI, 0.14-0.80]) and major or clinically relevant nonmajor bleeding (hazard ratio, 0.35 [95% CI, 0.17-0.72]) compared with warfarin. Patients with CrCl 25 to 30 mL/min randomized to apixaban demonstrated a trend toward lower rates of major bleeding when compared with those with CrCl >30 mL/min (P interaction=0.08) and major or clinically relevant nonmajor bleeding (P interaction=0.05). Median daily steady-state areas under the curve for apixaban 5 mg twice daily were 5512 ng/(mL·h) and 3406 ng/(mL·h) for patients with CrCl 25 to 30 mL/min or >30 mL/min, respectively. For apixaban 2.5 mg twice daily, the median exposure was 2780 ng/(mL·h) for patients with CrCl 25 to 30 mL/min. The area under the curve values for patients with CrCl 25 to 30 mL/min fell within the ranges demonstrated for patients with CrCl >30 mL/min. CONCLUSIONS: Among patients with atrial fibrillation and CrCl 25 to 30 mL/min, apixaban caused less bleeding than warfarin, with even greater reductions in bleeding than in patients with CrCl >30 mL/min. We observed substantial overlap in the range of exposure to apixaban 5 mg twice daily for patients with or without advanced chronic kidney disease, supporting conventional dosing in patients with CrCl 25 to 30 mL/min. Randomized, controlled studies evaluating the safety and efficacy of apixaban are urgently needed in patients with advanced chronic kidney disease, including those receiving dialysis. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00412984.

Risk markers of incident atrial fibrillation in patients with coronary heart disease.

BACKGROUND: In patients with coronary heart disease (CHD), atrial fibrillation (AF) is associated with increased morbidity and mortality. We investigated the associations between clinical risk factors and biomarkers with incident AF in patients with CHD. METHODS AND RESULTS: Around 13,153 patients with optimally treated CHD included in the STabilization of Atherosclerotic plaque By Initiation of darapLadIb TherapY (STABILITY) trial with plasma samples obtained at randomization. Mean follow-up time was 3.5 years. The association between clinical risk factors and biomarkers with incident AF was estimated with Cox-regression models. Validation was performed in 1,894 patients with non-ST-elevation acute coronary syndrome included in the FRISC-II trial. The median (min-max) age was 64 years (range 26-92) and 2,514 (19.1%) were women. A total of 541 patients, annual incidence rate of 1.2%, developed AF during follow-up. In multivariable models, older age, higher levels of NT-proBNP, higher body mass index (BMI), male sex, geographic regions, low physical activity, and heart failure were independently associated with increased risk of incident AF with hazard ratios ranging from 1.04 to 1.79 (P ≤ .05). NT-proBNP improved the C-index from 0.70 to 0.71. In the validation cohort, age, BMI, and NT-proBNP were associated with increased risk of incident AF with similar hazard ratios. CONCLUSIONS: In patients with optimally treated CHD, the incidence of new AF was 1.2% per year. Age, NT-proBNP as a marker of impaired cardiac function, and BMI were the strongest factors, independently and consistently associated with incident AF. Male sex and low physical activity may also contribute to the risk of AF in patients with CHD.

Angiotensin-converting enzyme 2 (ACE2) levels in relation to risk factors for COVID-19 in two large cohorts of patients with atrial fibrillation.

AIMS: The global COVID-19 pandemic is caused by the SARS-CoV-2 virus entering human cells using angiotensin-converting enzyme 2 (ACE2) as a cell surface receptor. ACE2 is shed to the circulation, and a higher plasma level of soluble ACE2 (sACE2) might reflect a higher cellular expression of ACE2. The present study explored the associations between sACE2 and clinical factors, cardiovascular biomarkers, and genetic variability. METHODS AND RESULTS: Plasma and DNA samples were obtained from two international cohorts of elderly patients with atrial fibrillation (n = 3999 and n = 1088). The sACE2 protein level was measured by the Olink Proteomics® Multiplex CVD II96 × 96 panel. Levels of the biomarkers high-sensitive cardiac troponin T (hs-cTnT), N-terminal probrain natriuretic peptide (NT-proBNP), growth differentiation factor 15 (GDF-15), C-reactive protein, interleukin-6, D-dimer, and cystatin-C were determined by immunoassays. Genome-wide association studies were performed by Illumina chips. Higher levels of sACE2 were statistically significantly associated with male sex, cardiovascular disease, diabetes, and older age. The sACE2 level was most strongly associated with the levels of GDF-15, NT-proBNP, and hs-cTnT. When adjusting for these biomarkers, only male sex remained associated with sACE2. We found no statistically significant genetic regulation of the sACE2 level. CONCLUSIONS: Male sex and clinical or biomarker indicators of biological ageing, cardiovascular disease, and diabetes are associated with higher sACE2 levels. The levels of GDF-15 and NT-proBNP, which are associated both with the sACE2 level and a higher risk for mortality and cardiovascular disease, might contribute to better identification of risk for severe COVID-19 infection.

Cardiovascular outcomes, bleeding risk, and achieved blood pressure in patients on long-term anticoagulation with the thrombin antagonist dabigatran or warfarin: data from the RE-LY trial.

AIMS: A J-shaped association of cardiovascular events to achieved systolic (SBP) and diastolic (DBP) blood pressure was shown in high-risk patients. This association on oral anticoagulation is unknown. This analysis from RELY assessed the risks of death, stroke or systemic emboli, and bleeding according to mean achieved SBP and DBP in atrial fibrillation on oral anticoagulation. METHODS AND RESULTS: RE-LY patients were followed for 2 years and recruited between 22 December 2005 until 15 December 2007. 18.113 patients were randomized in 951 centres in 54 countries and 18,107 patients with complete blood pressure (BP) data were analysed with a median follow-up of 2.0 years and a complete follow-up in 99.9%. The association between achieved mean SBP and DBP on all-cause death, stroke and systemic embolic events (SSE), major, and any bleeding were explored. On treatment, SBP >140 mmHg and <120 mmHg was associated with all-cause death compared with SBP 120-130 mmHg (reference). For SSE, risk was unchanged at SBP <110 mmHg but increased at 140-160 mmHg (adjusted hazard ratio (HR) 1.81; 1.40-2.33) and SBP ≥160 mmHg (HR 3.35; 2.09-5.36). Major bleeding events were also increased at <110 mmHg and at 110 to <120 mmHg. Interestingly, there was no increased risk of major bleeding at SBP >130 mmHg. Similar patterns were observed for DBP with an increased risk at <70 mmHg (HR 1.55; 1.35-1.78) and >90 mmHg (HR 1.88; 1.43-2.46) for all-cause death compared to 70 to <80 mmHg (reference). Risk for any bleeding was increased at low DBP <70 mmHg (HR 1.46; 1.37-1.56) at DBP 80 to <90 mmHg (HR 1.13; 1.06-1.31) without increased risk at higher achieved DBP. Dabigatran 150 mg twice daily showed an advantage in all patients for all-cause death and SSE and there was an advantage for 110 mg dabigatran twice daily for major bleeding and any bleeding irrespective of SBP or DBP achieved. Similar results were obtained for baseline BP, time-updated BP, and BP as time-varying covariate. CONCLUSION: Low achieved SBP associates with increased risk of death, SSE, and bleeding in patients with atrial fibrillation on oral anticoagulation. Major bleeding events did not occur at higher BP. Low BP might identify high-risk patients not only for death but also for high bleeding risks. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov-Identifier: NCT00262600.

Efficacy and Safety of Apixaban Versus Warfarin in Patients With Atrial Fibrillation and Extremes in Body Weight.

BACKGROUND: Guidelines caution against the use of non-vitamin K antagonist oral anticoagulants in patients with extremely high (>120 kg) or low (≤60 kg) body weight because of a lack of data in these populations. METHODS: In a post hoc analysis of ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation; n=18 201), a randomized trial comparing apixaban with warfarin for the prevention of stroke in patients with atrial fibrillation, we estimated the randomized treatment effect (apixaban versus warfarin) stratified by body weight (≤60, >60-120, >120 kg) using a Cox regression model and tested the interaction between body weight and randomized treatment. The primary efficacy and safety outcomes were stroke or systemic embolism and major bleeding. RESULTS: Of the 18 139 patients with available weight and outcomes data, 1985 (10.9%) were in the low-weight group (≤60 kg), 15 172 (83.6%) were in the midrange weight group (>60-120 kg), and 982 (5.4%) were in the high-weight group (>120 kg). The treatment effect of apixaban versus warfarin for the efficacy outcomes of stroke/systemic embolism, all-cause death, or myocardial infarction was consistent across the weight spectrum (interaction P value>0.05). For major bleeding, apixaban had a better safety profile than warfarin in all weight categories and even showed a greater relative risk reduction in patients in the low (≤60 kg; HR, 0.55; 95% CI, 0.36-0.82) and midrange (>60-120 kg) weight groups (HR, 0.71; 95% CI, 0.61-0.83; interaction P value=0.016). CONCLUSIONS: Our findings provide evidence that apixaban is efficacious and safe across the spectrum of weight, including in low- (≤60 kg) and high-weight patients (>120 kg). The superiority on efficacy and safety outcomes of apixaban compared with warfarin persists across weight groups, with even greater reductions in major bleeding in patients with atrial fibrillation with low to normal weight as compared with high weight. The superiority of apixaban over warfarin in regard to efficacy and safety for stroke prevention seems to be similar in patients with atrial fibrillation across the spectrum of weight, including in low- and very high-weight patients. Thus, apixaban appears to be appropriate for patients with atrial fibrillation irrespective of body weight. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00412984.