Protocol for a systematic review and network meta-analysis of the management of new onset atrial fibrillation in critically unwell adult patients

Development of Core Outcome Sets for trials on the management of Atrial fiBrillAtion in Critically Unwell patientS (COS-ABACUS): a protocol

INTRODUCTION

Atrial fibrillation (AF) is the most common cardiac arrhythmia in critically unwell patients. New-onset AF (NOAF) affects 5%-11% of all admissions and up to 46% admitted with septic shock. NOAF is associated with increased morbidity, mortality and healthcare costs. Existing trials into the prevention and management of NOAF suffer from significant heterogeneity making comparisons and inferences limited. Core outcome sets (COS) aim to standardise outcome reporting, reduce inconsistency between trials and reduce outcome reporting bias. We aim to develop an internationally agreed COS for trials of interventions on the management of NOAF during critical illness.

METHODS AND ANALYSIS

Stakeholders including intensive care physicians, cardiologists and patients will be recruited from national and international critical care organisations. COS development will occur in five stages: (1) Outcomes included in trials, recent systematic reviews and surveys of clinician practice and patient focus groups will be extracted. (2) Extracted outcomes will inform a two-stage e-Delphi process and consensus meeting using Grading of Recommendations Assessment, Development and Evaluation methodology. (3) Outcome measurement instruments (OMIs) will be identified from the literature and a consensus meeting held to agree OMI for core outcomes. (4) Nominal group technique will be used in a final consensus meeting to the COS. (5) The findings of our COS will be published in peer-reviewed journals and implemented in future guidelines and intervention trials.

ETHICS AND DISSEMINATION

The study has been approved by the University of Liverpool ethics committee (Ref: 11 256, 21 June 2022), with a formal consent waiver and assumed consent. We will disseminate the finalised COS via national and international critical care organisations and publication in peer-reviewed journals.

Association between Anemia and New-Onset Atrial Fibrillation in Critically Ill Patients in the Intensive Care Unit: A Retrospective Cohort Analysis

New-onset atrial fibrillation (NOAF) is one of the leading causes of morbidity and mortality, especially in older patients in the intensive care unit (ICU). Although many comorbidities are associated with NOAF, the effect of anemia on the onset of atrial fibrillation is still unknown. This study aimed to test the hypothesis that anemia is associated with an increased risk of developing NOAF in critically ill patients in intensive care. We performed a retrospective analysis of critically ill patients who underwent routine hemoglobin and electrocardiography monitoring in the ICU. Receiver operating characteristics analysis determined the hemoglobin (Hb) value that triggered NOAF formation. Bivariate correlation was used to determine the relationship between anemia and NOAF. The incidence of NOAF was 9.9% in the total population, and 12.8% in the patient group with anemia. Analysis of 1931 patients revealed a negative association between anemia and the development of NOAF in the ICU. The stimulatory Hb cut-off value for the formation of NOAF was determined as 9.64 g/dL. Anemia is associated with the development of NOAF in critically ill patients in intensive care.

Management of new onset atrial fibrillation in critically unwell adult patients: a systematic review and narrative synthesis

BACKGROUND

New onset atrial fibrillation (NOAF) is the most common arrhythmia affecting critically unwell patients. NOAF can lead to worsening haemodynamic compromise, heart failure, thromboembolic events, and increased mortality. The aim of this systematic review and narrative synthesis is to evaluate the non-pharmacological and pharmacological management strategies for NOAF in critically unwell patients.

METHODS

Of 1782 studies, 30 were eligible for inclusion, including 4 RCTs and 26 observational studies. Efficacy of direct current cardioversion, amiodarone, β-antagonists, calcium channel blockers, digoxin, magnesium, and less commonly used agents such as ibutilide are reported.

RESULTS

Cardioversion rates of 48% were reported for direct current cardioversion; however, re-initiation of NOAF was as high as 23.4%. Amiodarone was the most commonly reported intervention with cardioversion rates ranging from 18% to 95.8% followed by β-antagonists with cardioversion rates from 40% to 92.3%. Amiodarone was more effective than diltiazem (odds ratio [OR]=1.91, P=0.32) at cardioversion. Short-acting β-antagonists esmolol and landiolol were more effective compared with diltiazem at cardioversion (OR=3.55, P=0.04) and HR control (OR=3.2, P<0.001).

CONCLUSION

There was significant variation between studies with regard to the definition of successful cardioversion and heart rate control, making comparisons between studies and interventions difficult. Future RCTs comparing individual anti-arrhythmic agents, in particular magnesium, amiodarone, and β-antagonists, and the role of anticoagulation in critically unwell patients are required. There is also an urgent need for a core outcome dataset for studies of new onset atrial fibrillation to allow comparisons between different anti-arrhythmic strategies.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42019121739.

Comparative efficacy of pharmacological agents on reducing the risk of major adverse cardiovascular events in the hypertriglyceridemia population: a network meta-analysis

BACKGROUND

Hypertriglyceridemia (HTG) is considered an independent risk factor for major adverse cardiovascular events (MACE).

METHODS

This study analyzed the effects of various agents on MACE risk reduction in HTG (serum triglyceride ≥ 150 mg/dl) populations by performing a network meta-analysis. We performed a frequentist network meta-analysis to conduct direct and indirect comparisons of interventions. PubMed, EMBASE, and the Cochrane library were searched for trials until Jul 6, 2020. Randomized controlled trials that reported MACE associated with agents in entire HTG populations or in subgroups were included. The primary outcome was MACE.

RESULTS

Of the 2005 articles screened, 21 trials including 56,471 patients were included in the analysis. The network meta-analysis results for MACE risk based on frequency data showed that eicosapentaenoic acid (EPA) (OR: 1.32; 95% CI 1.19-1.46), gemfibrozil (OR: 1.53; 95% CI 1.20-1.95), niacin plus clofibrate (OR: 2.00; 95% CI 1.23-3.25), pravastatin (OR: 1.32; 95% CI 1.15-1.52), simvastatin (OR: 2.38; 95% CI 1.55-3.66), and atorvastatin (OR: 0.55; 95% CI 0.37-0.82) significantly reduced the risk of MACE compared to the control conditions. In the subgroup analysis of HTG patients with triglycerides ≥ 200 mg/dL, bezafibrate (OR: 0.56; 95% CI 0.33-0.94), EPA (OR: 0.72; 95% CI 0.62-0.82), and pravastatin (OR: 1.33; 95% CI 1.01-1.75) significantly reduced the MACE risk.

CONCLUSIONS

Simvastatin had a clear advantage in reducing the risk of MACE in the entire HTG population analyzed in this meta-analysis. EPA, but not omega-3 fatty acid, was considered an effective HTG intervention. Among fibrates, gemfibrozil was most effective, though bezafibrate may significantly reduce the risk of MACE in populations with triglyceride levels of 200-300 mg/dL. Trial registration retrospectively registered in PROSPERO (CRD42020213705).