Residual Stroke Risk in Atrial Fibrillation

Residual risk of thromboembolic events despite anticoagulation in Middle Eastern patients with atrial fibrillation. The JoFib study

OBJECTIVES

To investigate residual risk of thromboembolic events despite anticoagulation in patients with atrial fibrillation form the Middle East.

MATERIALS AND METHODS

Using data from the JoFib registry, we described the characteristics of patients treated with anticoagulants (n = 1654) and calculated the incidence rate for thromboembolic events. We constructed multivariable Cox proportional hazard models and calculated the population-attributable fraction to determine clinical factors predictive of residual thromboembolic events.

RESULTS

During the one-year follow-up, 57 thromboembolic events occurred (incidence rate 4.1 per 100 person-years). In multivariable time-to-event analysis, prior thromboembolic events (aHR 3.8, 95 %CI 2.2-6.4, p < 0.001) and diabetes (aHR 2.3, 95 %CI 1.3-4.1, p = 0.004) were independently predictive of residual thromboembolism. Percentage of thromboembolic risk attributable to prior thromboembolic events was 30.9 % (95 %CI 13.9-44.6, p = 0.001) and was 37.1 % (95 %CI 8.8-56.6, p = 0.015) for diabetes. Furthermore, the effect of diabetes on thromboembolic events depends on the type of anticoagulant, with diabetes being significantly predictive of thromboembolic events in patients anticoagulated with warfarin (aHR 4.11, 95 %CI 1.81-9.37, p = 0.001), but not non-vitamin K antagonist oral anticoagulants (aHR 1.23, 95 %CI 0.51-2.97, p = 0.643) with a p = 0.045 for interaction. Prior thromboembolism was independently predictive of thromboembolic events in both anticoagulants (aHR 2.67, 95 %CI 1.28-5.58, p = 0.009; aHR 7.33, 95 %CI 3.05-17.65, p < 0.001; respectively; p = 0.084 for interaction).

CONCLUSIONS

Middle Eastern patients with atrial fibrillation remain at significant risk of thromboembolism and its recurrence despite anticoagulation, and especially in diabetic patients. Therefore, management should focus on controlling diabetes as well as other modifiable risk factors in addition to antithrombotic therapy.

Predicting multifaceted risks using machine learning in atrial fibrillation: insights from GLORIA-AF study

Aims

Patients with atrial fibrillation (AF) have a higher risk of ischaemic stroke and death. While anticoagulants are effective at reducing these risks, they increase the risk of bleeding. Current clinical risk scores only perform modestly in predicting adverse outcomes, especially for the outcome of death. We aimed to test the multi-label gradient boosting decision tree (ML-GBDT) model in predicting risks for adverse outcomes in a prospective global AF registry.

Methods and results

We studied patients from phase II/III of the Global Registry on Long-Term Oral Anti-Thrombotic Treatment in Patients with Atrial Fibrillation registry between 2011 and 2020. The outcomes were all-cause death, ischaemic stroke, and major bleeding within 1 year following the AF. We trained the ML-GBDT model and compared its discrimination with the clinical scores in predicting patient outcomes. A total of 25 656 patients were included [mean age 70.3 years (SD 10.3); 44.8% female]. Within 1 year after AF, ischaemic stroke occurred in 215 (0.8%), major bleeding in 405 (1.6%), and death in 897 (3.5%) patients. Our model achieved an optimized area under the curve in predicting death (0.785, 95% CI: 0.757-0.813) compared with the Charlson Comorbidity Index (0.747, P = 0.007), ischaemic stroke (0.691, 0.626-0.756) compared with CHA2DS2-VASc (0.613, P = 0.028), and major bleeding (0.698, 0.651-0.745) as opposed to HAS-BLED (0.607, P = 0.002), with improvement in net reclassification index (10.0, 12.5, and 23.6%, respectively).

Conclusion

The ML-GBDT model outperformed clinical risk scores in predicting the risks in patients with AF. This approach could be used as a single multifaceted holistic tool to optimize patient risk assessment and mitigate adverse outcomes when managing AF.

Clinical phenotype classification to predict risk and optimize the management of patients with atrial fibrillation using the Atrial Fibrillation Better Care (ABC) pathway: a report from the COOL-AF registry

BACKGROUND

Phenotypic classification is a method of grouping patients with similar phenotypes.

AIM

We aimed to use phenotype classification based on a clustering process for risk stratification of patients with non-valvular atrial fibrillation (AF) and second, to assess the benefit of the Atrial Fibrillation Better Care (ABC) pathway.

METHODS

Patients with AF were prospectively enrolled from 27 hospitals in Thailand from 2014 to 2017, and followed up every 6 months for 3 years. Cluster analysis was performed from 46 variables using the hierarchical clustering using the Ward minimum variance method. Outcomes were a composite of all-cause death, ischemic stroke/systemic embolism, acute myocardial infarction and heart failure.

RESULTS

A total of 3405 patients were enrolled (mean age 67.8 ± 11.3 years, 58.2% male). During the mean follow-up of 31.8 ± 8.7 months. Three clusters were identified: Cluster 1 had the highest risk followed by Cluster 3 and Cluster 2 with a hazard ratio (HR) and 95% confidence interval (CI) of composite outcomes of 2.78 (2.25, 3.43), P < 0.001 for Cluster 1 and 1.99 (1.63, 2.42), P < 0.001 for Cluster 3 compared with Cluster 2. Management according to the ABC pathway was associated with reductions in adverse clinical outcomes especially those who belonged to Clusters 1 and 3 with HR and 95%CI of the composite outcome of 0.54 (0.40, 073), P < 0.001 for Cluster 1 and 0.49 (0.38, 0.63), P < 0.001 for Cluster 3.

CONCLUSION

Phenotypic classification helps in risk stratification and prognostication. Compliance with the ABC pathway was associated with improved clinical outcomes.

The relationship between right atrial wall inflammation and poor prognosis of atrial fibrillation based on 18F-FDG positron emission tomography/computed tomography

Background

Atrial fibrillation (AF) has been identified to increase stroke risk, even after oral anticoagulants (OACs), and the recurrence rate is high after radiofrequency catheter ablation (RFCA). Inflammation is an essential factor in the occurrence and persistence of AF. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is an established molecular imaging modality to detect local inflammation. We aimed to investigate the relationship between atrial inflammatory activity and poor prognosis of AF based on 18F-FDG PET/CT.

Methods

A total of 204 AF patients including 75 with paroxysmal AF (ParAF) and 129 with persistent AF (PerAF) who underwent PET/CT before treatment were enrolled in this prospective cohort study. Clinical data, electrocardiograph (ECG), echocardiography, and cardiac 18F-FDG uptake were collected. Follow-up information was obtained from patient clinical case notes or telephone reviews, with the starting point being the time of PET/CT scan. The follow-up deadline was either the date of AF recurrence after RFCA, new-onset stroke, or May 2023. Cox proportional hazards regression models were used to identify predictors of poor prognosis and hazard ratios (HRs) with 95% confidence intervals (CIs) was calculated.

Results

Median follow-up time was 29 months [interquartile range (IQR), 22-36 months]. Poor prognosis occurred in 52 patients (25.5%), including 34 new-onset stroke patients and 18 recrudescence after RFCA. The poor prognosis group had higher congestive heart failure, hypertension, age ≥75 years (doubled), diabetes mellitus, prior stroke or transient ischemic attack (TIA) or thromboembolism (doubled), vascular disease, age 65-74 years, sex category (female) (CHA2DS2-VASc) score [3.0 (IQR, 1.0-3.75) vs. 2.0 (IQR, 1.0-3.0), P=0.01], right atrial (RA) wall maximum standardized uptake value (SUVmax) (4.13±1.82 vs. 3.74±1.58, P=0.04), higher percentage of PerAF [39 (75.0%) vs. 90 (59.2%), P=0.04], left atrial (LA) enlargement [45 (86.5%) vs. 104 (68.4%), P=0.01], and RA wall positive FDG uptake [40 (76.9%) vs. 79 (52.0%), P=0.002] compared with the non-poor prognosis group. Univariate and multivariate Cox proportional hazard regression analysis concluded that only CHA2DS2-VASc score (HR, 1.29; 95% CI: 1.06-1.57; P=0.01) and RA wall positive FDG uptake (HR, 2.68; 95% CI: 1.10-6.50; P=0.03) were significantly associated with poor prognosis.

Conclusions

RA wall FDG positive uptake based on PET/CT is tightly related to AF recurrence after RFCA or new-onset stroke after antiarrhythmic and anticoagulation treatment.

Validating the predictive ability of the 2MACE score for major adverse cardiovascular events in patients with atrial fibrillation: results from phase II/III of the GLORIA-AF registry

The 2MACE score was specifically developed as a risk-stratification tool in atrial fibrillation (AF) to predict cardiovascular outcomes. We evaluated the predictive ability of the 2MACE score in the GLORIA-AF registry. All eligible patients from phase II/III of the prospective global GLORIA-AF registry were included. Major adverse cardiac events (MACEs) were defined as the composite outcome of stroke, myocardial infarction and cardiovascular death. Cox proportional hazards were used to examine the relationship between the 2MACE score and study outcomes. Predictive capability of the 2MACE score was investigated using receiver-operating characteristic curves. A total of 25,696 patients were included (mean age 71 years, female 44.9%). Over 3 years, 1583 MACEs were recorded. Patients who had MACE were older, with more cardiovascular risk factors and were less likely to be managed using a rhythm-control strategy. The median 2MACE score in the MACE and non-MACE groups were 2 (IQR 1-3) and 1 (IQR 0-2), respectively (p < 0.001). The 2MACE score was positively associated with an increase in the risk of MACE, with a score of ≥ 2 providing the best combination of sensitivity (69.6%) and specificity (51.6%), HR 2.47 (95% CI, 2.21-2.77). The 2MACE score had modest predictive performance for MACE in patients with AF (AUC 0.655 (95% CI, 0.641-0.669)). Our analysis in this prospective global registry demonstrates that the 2MACE score can adequately predict the risk of MACE (defined as myocardial infarction, CV death and stroke) in patients with AF. Clinical trial registration: http://www.clinicaltrials.gov . Unique identifiers: NCT01468701, NCT01671007 and NCT01937377.

Very-high-power Short-duration Ablation versus Conventional Ablation for Pulmonary Vein Isolation in Atrial Fibrillation: Systematic Review and Meta-analysis

The aim of this study was to compare the effectiveness and safety of very-high-power short-duration (VHPSD) ablation (70-90 W/4-7 s) with conventional ablation (30-40 W/>20 s, 50 W/7-11 s) for pulmonary vein isolation (PVI) in patients with AF. A total of 13 studies were included in this analysis (1,527 patients). AF recurrence occurred in 14% (95% CI [11-18%]) of the VHPSD group. VHPSD was associated with lower AF recurrence (OR 0.65; 95% CI [0.48-0.89]; p=0.006) compared with the conventional ablation group. Subgroup analysis showed that additional ablation beyond PVI had a similar rate of AF recurrence (16% versus 10%) compared with PVI alone. Procedure and ablation durations were significantly shorter in the VHPSD group with a mean differences of -14.4 minutes (p=0.017) and -14.1 minutes (p<0.001), respectively. Complications occurred in 6% (95% CI [3-9%]) of the VHPSD group, and the rate was similar between the two groups (OR 1.03; 95% CI [0.60-1.80]; p=0.498). VHPSD ablation resulted in less AF recurrence and a shorter procedure time. Additional ablation beyond PVI alone in VHPSD may not provide additional benefits.

Network Meta-Analysis of Initial Antithrombotic Regimens After Left Atrial Appendage Occlusion

BACKGROUND

The optimal antithrombotic therapy following left atrial appendage occlusion (LAAO) in patients with nonvalvular atrial fibrillation (AF) remains uncertain.

OBJECTIVES

In this study, the authors sought to compare the efficacy and safety of various antithrombotic strategies after LAAO.

METHODS

We searched the Medline, Cochrane, EMBASE, LILACS, and ClinicalTrials.gov databases for studies reporting outcomes after LAAO, stratified by antithrombotic therapy prescribed at postprocedural discharge. Direct oral anticoagulants (DOACs), vitamin K antagonists (VKAs), single antiplatelet therapy (SAPT), dual antiplatelet therapy (DAPT), DOAC plus SAPT, VKA plus SAPT, and no antithrombotic therapy were analyzed. We performed a frequentist random effects model network meta-analysis to estimate the OR and 95% CI for each comparison. P-scores provided a ranking of treatments.

RESULTS

Forty-one studies comprising 12,451 patients with nonvalvular AF were included. DAPT, DOAC, DOAC plus SAPT, and VKA were significantly superior to no therapy to prevent device-related thrombosis. DOAC was associated with lower all-cause mortality than VKA (OR: 0.39; 95% CI: 0.17-0.89; P = 0.03). Compared with SAPT, DAPT was associated with fewer thromboembolic events (OR: 0.50; 95% CI: 0.29-0.88; P = 0.02), without a difference in major bleeding. In the analysis of P-scores, DOAC monotherapy was the strategy most likely to have lower thromboembolic events and major bleeding.

CONCLUSIONS

In this network meta-analysis comparing initial antithrombotic therapies after LAAO, monotherapy with DOAC had the highest likelihood of lower thromboembolic events and major bleeding. DAPT was associated with a lower incidence of thromboembolic events compared with SAPT and may be a preferred option in patients unable to tolerate anticoagulation.

Clinical outcomes of oral anticoagulant discontinuation in atrial fibrillation: a systematic review and meta-analysis

INTRODUCTION

Oral anticoagulants (OACs) should generally be continued lifelong in patients with atrial fibrillation (AF) to ensure optimal benefits, unless contraindications arise. However, discontinuation of OACs might occur for various reasons, potentially affecting clinical outcomes. In this review, we synthesized evidence on the clinical outcomes following OAC discontinuation in patients with AF.

METHODS

We conducted a systematic review and meta-analysis using PubMed, Embase and Scopus. Cohort or case-control studies were included if data were available on clinical outcomes of OAC discontinuation, compared with continuation, in patients with AF. A random-effect meta-analyses were conducted for key outcomes of stroke, mortality, and major bleeding.

RESULTS

Eighteen observational studies having a total of 283,418 patients were included. Discontinuation significantly increased the risk of stroke (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.58-2.23), all-cause (HR 1.90; 95% CI 1.40-2.59) and cardiovascular (HR 1.83; 95% CI 1.06-3.18) mortality. The risk of major bleeding was not significantly different between the discontinued and continued groups (HR 1.04; 95% CI 0.72-1.52).

CONCLUSIONS

Discontinuation of OAC therapy was associated with an increased risk of stroke and mortality, with no difference in the risk of major bleeding. Acknowledging heterogeneity among the studies, the findings underline the need to ensure continuity of OAC therapy in patients with AF to prevent thrombotic complications and associated mortality.

PROSPERO REGISTRATION NUMBER

CRD42020186116.

Contemporary management of atrial fibrillation and the predicted vs. absolute risk of ischaemic stroke despite treatment: a report from ESC-EHRA EORP-AF Long-Term General Registry

BACKGROUND

Risk stratification in patients with atrial fibrillation (AF) is important to facilitate guideline-directed therapies. The Calculator of Absolute Stroke Risk (CARS) scheme enables an individualized estimation of 1-year absolute risk of stroke in AF. We aimed to investigate the predicted and absolute risks of ischaemic stroke, and evaluate whether CARS (and CHA2DS2-VASc score) may be useful for identifying high risk patients with AF despite contemporary treatment.

METHODS

We utilized the EORP-AF General Long-Term Registry which prospectively enrolled patients with AF from 250 centres across 27 participating European countries. Patients with sufficient data to determine CARS and CHA2DS2-VASc score, and reported outcomes of ischaemic stroke were included in this analysis. The primary outcome of ischaemic stroke was recorded over a 2-year follow-up period.

RESULTS

A total of 9444 patients were included (mean age 69.1 [±11.4] years; 3776 [40.0%] females). There was a high uptake (87.9%) of anticoagulation therapy, predominantly with vitamin K antagonist (50.0%). Over a mean follow-up period of 24 months, there were a total of 101 (1.1%) ischaemic stroke events. In the entire cohort, the median CARS and absolute annual risks of ischaemic stroke were 2.60 (IQR 1.60-4.00) and 0.53% (95%CI 0.43-0.64%), respectively. There was no statistical difference between the predictive performance of CARS and CHA2DS2-VASc score (0.621 [95%CI 0.563-0.678] vs. 0.626 [95%CI 0.573-0.680], P = 0.725).

CONCLUSION

Contemporary management of AF was associated with a low risk of ischaemic stroke. CARS and CHA2DS2-VASc score may be useful to identify high risk patients despite treatment who may benefit from more aggressive treatment and follow-up.

Incidence and Risk Factors for Residual Adverse Events Despite Anticoagulation in Atrial Fibrillation: Results From Phase II/III of the GLORIA-AF Registry

Background Residual risk of ischemic stroke despite anticoagulation in patients with atrial fibrillation (AF) represents a significant clinical issue that remains unaddressed. We aimed to evaluate the incidence and risk factors for residual adverse events in AF. Methods and Results Using data from phase II/III of the prospective GLORIA-AF (Global Registry on Long-Term Oral Anti-thrombotic Treatment in Patients With Atrial Fibrillation) registry, we studied anticoagulated patients with newly diagnosed AF and an increased risk of stroke (CHA2DS2-VASc ≥1). The primary outcome of interest was ischemic stroke. Secondary outcomes were all-cause death, cardiovascular death and myocardial infarction. A total of 22 410 patients were included; median age 65 (interquartile range 71-78) and 10 044 (44.8%) were female. During a median follow-up period of 3.0 (interquartile range 2.2-3.1) years, the incidence of ischemic stroke was 0.60 (95% CI, 0.54-0.67) per 100-PYs, all-cause death 3.22 (95% CI, 3.08-3.37) per 100-PYs, cardiovascular death 1.08 (95% CI, 1.00-1.16) per 100-PYs and myocardial infarction 0.59 (95% CI, 0.53-0.66) per 100-PYs. Using multivariable Cox proportional hazards analysis, independent predictors of residual ischemic stroke were age (HR 1.05 [95% CI, 1.03-1.07]), diabetes (HR 1.42 [95% CI, 1.08-1.87]), prior thromboembolism (HR 2.27 [95% CI, 1.73-2.98]) and use of antiarrhythmic drugs (HR 0.66 [95% CI, 0.47-0.92]). The incidence of ischemic stroke was comparable among patients treated with nonvitamin K antagonist oral anticoagulants versus vitamin K antagonist; however, there were differences in the independent predictors between both groups. Conclusions Patients with AF remain at significant residual risk of developing complications including ischemic stroke despite anticoagulation therapy. Further efforts among these patients should be directed at the management of modifiable risk factors that contribute to this risk. Registration URL: http://www.clinicaltrials.gov; Unique identifiers: NCT01468701, NCT01671007 and NCT01937377.

Association Between Inappropriately Dosed Anticoagulation Therapy With Stroke Severity and Outcomes in Patients With Atrial Fibrillation

Background

Oral anticoagulation (OAC) is effective for stroke prevention in patients with atrial fibrillation. However, some patients experience stroke despite OAC therapy, and knowledge about the impact of prior treatment quality is lacking.

Methods and Results

Patients with atrial fibrillation on OAC therapy who had a first‐time ischemic stroke were identified in the Danish Stroke Registry (2005–2018). Patients treated with vitamin K antagonist (VKA) therapy were compared according to the international normalized ratio just before stroke (international normalized ratio <2 [subtherapeutic], international normalized ratio 2–3 [therapeutic], international normalized ratio >3 [supratherapeutic]), and patients on underdosed, appropriately dosed, and overdosed direct OAC (DOAC) therapy were compared. Stroke severity was determined using the Scandinavia Stroke Scale (0–58 points), and the risk of very severe stroke (0–14 points) was analyzed by multivariable logistic regression. One‐year mortality was determined using multivariable Cox regression. A total of 2319 patients with atrial fibrillation and stroke were included; 1196 were taking a VKA (subtherapeutic [46%], therapeutic [43%], supratherapeutic [11%]), and 1123 were taking DOAC (underdosed [23%], appropriately dosed [60%], and overdosed [17%]). Subtherapeutic and supratherapeutic VKA therapy (compared with therapeutic) and underdosed DOAC therapy (compared with appropriate and underdosed DOAC) patients were older, more often women, and more comorbid. Subtherapeutic VKA therapy was associated with very severe stroke (odds ratio [OR], 2.06 [95% CI, 1.28–3.31]), whereas supratherapeutic VKA therapy was not (OR, 1.24 [95% CI, 0.60–2.57]) compared with therapeutic VKA therapy. Patients on subtherapeutic and supratherapeutic VKA therapy had a higher 1‐year mortality (hazard ratio [HR], 1.66 [95% CI, 1.29–2.13]); HR, 1.55 [95% CI, 1.08–2.22], respectively) than those on therapeutic VKA therapy. Treatment with underdosed or overdosed DOAC therapy was not associated with very severe stroke (OR, 1.27 [95% CI, 0.76–2.15]; OR, 0.73 [95% CI, 0.37–1.43], respectively) and was not associated with 1‐year mortality (HR, 1.09 [95% CI, 0.83–1.44]; HR, 0.82 [95% CI, 0.57–1.18], respectively) than appropriate DOAC.

Conclusions

Half of the patients with atrial fibrillation with stroke were on inappropriate OAC therapy. Subtherapeutic VKA was associated with worse stroke severity and higher mortality rate than therapeutic VKA therapy. Neither underdosed nor overdosed DOAC was associated with worse outcomes in adjusted models compared with appropriately dosed DOAC. This study supports DOAC as a first‐line therapy over VKA.