Imaging in atrial fibrillation: A way to assess atrial fibrosis and remodeling to assist decision-making

The 2020 ESC atrial fibrillation (AF) guidelines suggest the novel 4S-AF scheme for the characterization of AF. Imaging techniques could be helpful for this objective in everyday clinical practice, and information derived from these techniques reflects basic aspects of the pathophysiology of AF, which may facilitate treatment decision-making, and optimal management of AF patients. The aim of this review is to provide an overview of the mechanisms associated with atrial fibrosis and to describe imaging techniques that may help the management of AF patients in clinical practice. Transthoracic echocardiography is the most common procedure given its versatility, safety, and simplicity. Transesophageal echocardiography provides higher resolution exploration, and speckle tracking echocardiography can provide incremental functional and prognostic information over conventional echocardiographic parameters. In addition, LA deformation imaging, including LA strain and strain rate, are related to the extent of fibrosis. On the other hand, multidetector-row computed tomography and cardiac magnetic resonance provide higher resolution data and more accurate assessment of the dimensions, structure, and spatial relationships of the LA. Imaging is central when deciding on catheter ablation or cardioversion, and helps in selecting those patients who will really benefit from these procedures. Moreover, imaging enhances the understanding of the underlying mechanisms of atrial remodeling and might assists in refining the risk of stroke, which help to select the best medical therapies/interventions. In summary, evaluation of LA enlargement, LA remodeling and fibrosis with imaging techniques adds clinical and prognostic information and should be assessed as a part of routine comprehensive AF evaluation.

Intravenous Alteplase at 0.6 mg/kg for Unknown Onset Stroke with Prior Antithrombotic Medication: THAWS Randomized Clinical Trial

AIM

This study aimed to assess the potential effect of prior antithrombotic medication for thrombolysis in an unknown onset stroke.

METHODS

This was a predefined sub-analysis of the THAWS trial. Stroke patients with a time last known well ＞4.5 h who had a DWI-fluid-attenuated inversion recovery mismatch were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg (alteplase group) or standard medical treatment (control group). Patients were dichotomized by prior antithrombotic medication.

RESULTS

Of 126 patients (intention-to-treat population), 40 took antithrombotic medication (24 with antiplatelets alone, 13 with anticoagulants alone, and 3 with both), and the remaining 86 did not before stroke onset. Of these, 17 and 52 patients, respectively, received alteplase, and 23 and 34, respectively, had standard medical treatment. Antithrombotic therapy was initiated within 24 h after randomization less frequently in the alteplase group (12% vs. 86%, p＜0.01). Both any intracranial hemorrhage within 22-36 h (26% vs. 14%) and a modified Rankin Scale score of 0-1 at 90 days (good outcome) (47% vs. 48%) were comparable between the two groups. A good outcome was more common in the alteplase group than in the control group in patients with prior antithrombotic medication [relative risk (RR) 2.25, 95% confidence interval (CI) 1.02-4.99], but it tended to be less common in the alteplase group in those without (RR 0.69, 95% CI 0.46-1.03) (p＜0.01 for interaction). The frequency of any intracranial hemorrhage did not significantly differ between the two groups in any patients dichotomized by prior antithrombotic medication.

CONCLUSION

Alteplase appears more beneficial in patients with prior antithrombotic medication.

Prediction Model of New Onset Atrial Fibrillation in Patients with Acute Coronary Syndrome

OBJECTIVE

Atrial fibrillation (AF) is one of the most common complications of acute coronary syndrome (ACS) patients. Possible risk factors related to new-onset AF (NOAF) in ACS patients have been reported in some studies, and several prediction models have been established. However, the predictive power of these models was modest and lacked independent validation. The aim of this study is to define risk factors of NOAF in patients with ACS during hospitalization and to develop a prediction model and nomogram for individual risk prediction.

METHODS

Retrospective cohort studies were conducted. A total of 1535 eligible ACS patients from one hospital were recruited for model development. External validation was performed using an external cohort of 1635 ACS patients from another hospital. The prediction model was created using multivariable logistic regression and validated in an external cohort. The discrimination, calibration, and clinical utility of the model were evaluated, and a nomogram was constructed. A subgroup analysis was performed for unstable angina (UA) patients.

RESULTS

During hospitalization, the incidence of NOAF was 8.21% and 6.12% in the training and validation cohorts, respectively. Age, admission heart rate, left atrial diameter, right atrial diameter, heart failure, brain natriuretic peptide (BNP) level, less statin use, and no percutaneous coronary intervention (PCI) were independent predictors of NOAF. The AUC was 0.891 (95% CI: 0.863-0.920) and 0.839 (95% CI: 0.796-0.883) for the training and validation cohort, respectively, and the model passed the calibration test (P > 0.05). The clinical utility evaluation shows that the model has a clinical net benefit within a certain range of the threshold probability.

CONCLUSION

A model with strong predictive power was constructed for predicting the risk of NOAF in patients with ACS during hospitalization. It might help with the identification of ACS patients at risk and early intervention of NOAF during hospitalization.

Age-dependent risk for thromboembolism in atrial fibrillation: The Fushimi AF registry

Background

The risk for thromboembolism depending on the different age subgroups in patients with atrial fibrillation (AF) has not been fully elucidated.

Methods

The Fushimi AF Registry is a community-based prospective survey of patients with AF in Fushimi-ku, Kyoto. Follow-up data were available for 4,466 patients by the end of 2019. Clinical determinants and the description of variables which interact and lead to the incidence of thromboembolism (the composite of ischemic stroke and systemic embolism [SE]) were identified in overall population and in age subgroups (≤64, 65–74, and ≥ 75 years).

Results

A total of 314 patients developed thromboembolism during the median follow-up of 1,610 days (1.56 per 100 person-years). The independent determinants were age advance (per 10 years, hazard ratio [HR]: 1.51, 95% confidence interval [CI]: 1.22–1.86, P < 0.001), low body weight (HR: 1.91, 95% CI: 1.35–2.70, P < 0.001), history of stroke or SE (HR: 2.06, 95% CI: 1.54–2.76, P < 0.001), chronic kidney disease (HR: 1.34, 95% CI: 1.01–1.78, P = 0.043), and left atrial enlargement (HR: 1.57, 95% CI: 1.18–2.10, P = 0.0021). With regard to the age subgroup analysis, diabetes mellitus (P = 0.043), vascular disease (P = 0.005), male sex (P = 0.022), and sustained AF (P = 0.014) indicated significantly relevant interactions between the age subgroups and thromboembolism.

Conclusion

The risk and the impact of baseline characteristics on thromboembolism in patients with AF varied depending on the age subgroups.

Comparison of the Efficacy and Safety Endpoints of Five Therapies for Atrial Fibrillation: A Network Meta-Analysis

Introduction

Atrial fibrillation (AF) is a prevalent arrhythmia that occurs in 2–4% of adults and poses a threat to human health. Thus, comparison of the efficacy and safety of therapies for AF is warranted. Here, we used network analysis to compare efficacy (arrhythmia recurrence and re-hospitalization) and safety (ischemic cerebral vascular events, all-cause mortality, and cardiovascular mortality) endpoints among five major therapies for AF.

Methods

The PubMed, Cochrane, and Embase databases were searched, and relevant literature was retrieved. Only studies that made comparisons among the therapies of interest and involved patients with AF were included. Pairwise comparisons and frequentist method (SUCRA plot) analyses were conducted.

Results

In total, 62 studies were included in the pooled analysis. In pairwise comparisons, atrioventricular nodal ablation plus permanent pacemaker (AVN + PPM) was associated with a significantly higher risk of atrial arrhythmia recurrence than surgical ablation [odds ratio (OR): 23.82, 95% confidence interval (CI): 1.97–287.59, fixed-effect model; 3.82, 95% CI: 1.01–559.74, random-effects model]. Furthermore, radiofrequency ablation was associated with a significantly lower risk of cardiovascular mortality than medication in pairwise comparison (OR: 0.49, 95% CI: 0.29–0.83, fixed-effect model; OR: 0.49, 95% CI: 0.27–0.9, random-effects model). Frequentist analysis indicated that AVN + PPM had the best performance in reducing the risk of safety and efficacy endpoints.

Conclusion

Non-pharmaceutical therapies showed superior performance to traditional drug therapy in lowering the risk of safety and efficiency endpoint events. AVN + PPM performed best in reducing the risk of safety and efficacy endpoints.

Failure of Therapeutic Anticoagulation in COVID-19 Patients With Acute Ischemic Stroke. A Retrospective Multicenter Study

Background

Acute ischemic stroke (AIS) is a possible complication of coronavirus disease 2019 (COVID-19) infection. Although peculiar clinical features and underlying specific mechanisms of thrombogenesis have been suggested so far, there is no consensus on the appropriate vascular preventive drug regimen in patients with COVID-19.

Aim and Methods

From a larger clinical series of consecutive acute ischemic strokes related to COVID-19 admitted to three cerebrovascular units in Northern Italy, herein, we describe the clinical features of a subgroup of patients in whom stroke occurred despite therapeutic anticoagulation.

Results

A total of seventeen/80 AIS related to COVID-19 (21.2%) occurred in anticoagulated patients. Although no blood level was available for Direct Oral AntiCoagulant, the drug dosage was appropriate according to guidelines. Their National Institute of Health Stroke Scale (NIHSS) at admission was 12.0 (SD = 7.4) and 58.8% of them had evidence of large vessel occlusion. The case fatality rate was as high as 64.7%.

Discussion and Conclusions

The occurrence of an anticoagulation failure seems to be increased in the setting of COVID-19 infection, with worse clinical outcomes if compared to non-COVID-19 related ischemic strokes. We discuss the diagnostic and therapeutic implications of such evidence, suggesting that some arterial thrombotic complications might be either resistant to or independent of the anticoagulation effect.

A Novel Factor in Determining the Risk of Ischemic Cerebrovascular Events in Patients with Atrial Fibrillation: Pulmonary Hypertension

OBJECTIVES

Pulmonary hypertension (PH) is closely related to clinical decompensation and poor clinical outcomes in atrial fibrillation (AF) patients. However, the association between PH and ischemic cerebrovascular events (ICE) in AF patients has not been investigated. The authors purposed to examine this relationship.

MATERIALS AND METHODS

The researchers conducted an observational study on 371 AF patients between January and November 2021. In line with the European Society of Cardiology guideline recommendations, echocardiographic parameters suggestive of PH were performed. The study population was stratified into two groups based on the presence (n = 98, 31%) or non-presence (n = 219, 69%) of PH. Also, we did logistic regression analyses for the independent predictors of the ICEs in AF patients.

RESULTS

Ischemic cerebrovascular events were significantly more frequent in the PH group than the non-PH group (n = 30, 13% vs. n = 18, 18%, p = 0.03). At univariable analysis, hypertension, diabetes mellitus, PH (OR = 0.23 [95% CI, 0.13-0.41], p = 0.005) and diastolic dysfunction were significantly related to ICE in AF patients. Moreover, at multivariable analysis, age, diabetes mellitus, PH (OR = 0.19 [95% CI, 0.10-0.36], p = 0.01), and diastolic dysfunction were predictive of ICE.

CONCLUSIONS

Pulmonary hypertension is likely associated with ischemic cerebrovascular events in patients with AF, requiring further investigation to determine its association.

Sleep in Neurologic Disorders

Sleep is a complex brain state with fundamental relevance for cognitive functions, synaptic plasticity, brain resilience, and autonomic balance. Sleep pathologies may interfere with cerebral circuit organization, leading to negative consequences and favoring the development of neurologic disorders. Conversely, the latter can interfere with sleep functions. Accordingly, assessment of sleep quality is always recommended in the diagnosis of patients with neurologic disorders and during neurorehabilitation programs. This review investigates the complex interplay between sleep and brain pathologies, focusing on diseases in which the association with sleep disturbances is commonly overlooked and whereby major benefits may derive from their proper management.