Emergency Department Visits for Atrial Fibrillation in the United States: Trends in Admission Rates and Economic Burden From 2007 to 2014

Safety of Diltiazem for Acute Management of Atrial Fibrillation (AF) in Patients with Heart Failure and Reduced Ejection Fraction in the Emergency Department

BACKGROUND

Diltiazem is an effective rate control agent for atrial fibrillation with rapid ventricular rate (AF RVR). However, its negative inotropic effects may increase the risk for worsening heart failure in patients with a reduced ejection fraction (EF).

OBJECTIVES

This observational study aims to describe the incidence of worsening heart failure in patients who receive intravenous diltiazem for acute atrial fibrillation management.

METHODS

Adult patients that received diltiazem in the emergency department (ED) for AF RVR (heart rate ≥ 100 beats/min) from 2021 to 2022 and had a prior documented EF were included. The primary outcome is worsening heart failure within 24 h of diltiazem administration. Secondary outcomes include return ED visits and death within 7 days. EF percentage was compared across outcomes using Wilcoxon rank-sum tests. Outcomes were compared by reduced EF (< 50%) and preserved EF (≥ 50%). Continuous data were summarized with medians and interquartile ranges, and categorical features were summarized with frequency counts and percentages. Wilcoxon rank-sum tests were used for numeric outcomes and chi-squared tests or Fisher's exact tests for categorical outcomes, with a p-value < 0.05 considered statistically significant.

RESULTS

There were 674 patients with AF RVR that received diltiazem, and 386 patients met the inclusion criteria for analysis. Baseline demographics included a median age of 72 (64-81) years, with 14.5% of patients having a prior diagnosis of congestive heart failure. EF < 50% was identified in 13.7% of patients (n = 53), of which approximately 30% of these patients safely discharged home after receiving i.v. diltiazem. The primary outcome of worsening heart failure occurred in 7/41 (17%) and 10/207 (4.8%) patients with reduced and preserved ejection fractions, respectively, who were admitted to the hospital (p = 0.005).

CONCLUSION

The development of worsening heart failure is multifactorial and may include the use of diltiazem in critically ill patients requiring hospital admission.

Decision Support Intervention and Anticoagulation for Emergency Department Atrial Fibrillation: The O'CAFÉ Stepped-Wedge Cluster Randomized Clinical Trial

Importance

Oral anticoagulation for adults with atrial fibrillation or atrial flutter (AFF) who are at elevated stroke risk reduces the incidence of ischemic stroke but remains underused. Efforts to increase anticoagulation initiation on emergency department (ED) discharge have yielded conflicting results.

Objective

To evaluate the effectiveness of a multipronged intervention supporting anticoagulation initiation for eligible adult ED patients.

Design, Setting, and Participants

The Clinical Decision Support to Optimize Care of Patients With Atrial Fibrillation or Flutter in the Emergency Department (O'CAFÉ) pragmatic, stepped-wedge cluster randomized clinical trial was conducted from July 1, 2021, through April 30, 2023, at 13 community medical centers (in 9 clusters) of an integrated health system in Northern California. The study included adult ED patients with primary AFF eligible for anticoagulation initiation when discharged home. Clusters were randomly assigned to staggered dates for 1-way crossover from the control phase (usual care) to the intervention phase.

Intervention

Physician education, facility-specific audit and feedback, and access to decision support, which identified eligible patients and recommended shared decision-making, anticoagulation initiation (if suitable), and timely follow-up.

Main Outcomes and Measures

The main outcome was a composite of anticoagulation on discharge or within 30 days. A primary intention-to-treat analysis (decision support access regardless of use) and a secondary per-protocol analysis (decision support use) were performed. Multivariable analyses adjusted for intervention and exposure months with random effects, accounting for clustering by facility and patient.

Results

A total of 3388 eligible patients with atrial fibrillation were discharged home: 2185 (64.5%) were receiving pre-ED arrival anticoagulation and 1203 (35.5%) were eligible for anticoagulation. Among the 1203 patients with an initiation-eligible encounter, the median age was 74.0 (IQR, 68.0-82.0) years and approximately half (618 [51.4%]) were men. Among the 387 patients with an initiation-eligible control encounter, 244 (63.0%) received anticoagulation (190 [49.0%] at discharge and 54 [14.0%] within 30 days). Among the 816 patients with an initiation-eligible intervention encounter, 558 (68.4%) received anticoagulation (428 [52.5%] on discharge and 130 [15.9%] within 30 days). There was no statistically significant change in initiation of anticoagulation associated with the intervention (adjusted odds ratio, 1.33 [95% CI, 0.75-2.35]; P = .13). Decision support was used for 217 eligible case patients (26.6%) (per protocol) and was associated with a statistically significant change in anticoagulation initiation when compared with 599 patients for whom decision support was not used (164 [75.6%] vs 394 [65.8%]; P = .008).

Conclusions and Relevance

In this trial, a multipronged intervention to facilitate thromboprophylaxis among eligible ED patients with AFF did not significantly increase anticoagulation initiation. Opportunities exist to further improve stroke prevention among ED patients with primary AFF.

Trial Registration

ClinicalTrials.gov Identifier: NCT05009225.

Efficacy and Safety of Intravenous Diltiazem Versus Metoprolol in the Management of Atrial Fibrillation with Rapid Ventricular Response in the Emergency Department: A Comprehensive Umbrella Review of Systematic Reviews and Meta-analyses

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the United States, affecting 2.7-6.1 million people. AF can cause symptoms, but when it triggers a rapid ventricular response (RVR), most patients suffer from decompensation. Therefore, we performed an umbrella review of systematic reviews and meta-analyses comparing intravenous (IV) metoprolol and diltiazem to identify discrepancies, fill in knowledge gaps, and develop standardized decision-making guidelines for physicians to manage AF with RVR. A comprehensive search was conducted in PubMed, the Cochrane Library, and Scopus to identify studies for this umbrella review. The overall certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation method, while the quality of the included reviews was evaluated using AMSTAR 2, the Cochrane Collaboration tool, and the Newcastle-Ottawa scale. This study comprehensively analyzed four meta-analyses covering 11 randomized controlled trials and 19 observational studies. The analysis showed that IV diltiazem treatment was significantly more successful in rate control for AF with rapid ventricular response (RVR) than IV metoprolol (risk ratio [RR], 1.30; 95% confidence interval [CI], 1.09-1.56; I 2 = 0%; P = .003). IV diltiazem also led to a significantly greater reduction in ventricular rate (mean difference, -14.55; 95% CI, -16.93 to -12.16; I 2 = 72%; P < .00001), particularly at 10 min. The analysis also revealed a significantly increased risk of hypotension associated with treatment with IV diltiazem (RR, 1.43; 95% CI, 1.14-1.79; I 2 = 0%; P = .002). In conclusion, IV diltiazem therapy achieved better rate control and ventricular rate decrease than metoprolol therapy in AF with RVR. Future clinical trials should compare calcium channel blockers and β-blockers for heart rate control efficacy and safety, considering adverse events.

Impact of an Organized Treatment Pathway on Management of Atrial Fibrillation: The ER2EP Study

Background

Atrial fibrillation (AF) is the most common arrhythmia reported worldwide. There is significant heterogeneity in AF care pathways for a patient seen in the emergency room, impacting access to guideline-driven therapies.

Objectives

The purpose of this study was to compare the difference in AF outcomes between those treated with an organized treatment pathway vs routine-care approach.

Methods

The emergency room to electrophysiology service study (ER2EP) is a multicenter, prospective observational registry (NCT04476524) enrolling patients with AF from sites where a pathway for management of AF was put in place compared to sites where a pathway was not in place within the same health system and the same physicians providing services at all sites. Multivariable regression modeling was performed to identify predictors of clinical outcomes. Beta coefficient or odds ratio was reported as appropriate.

Results

A total of 500 patients (ER2EP group, n = 250; control group, n = 250) were included in the study. The mean age was 73.4 ± 12.9 years, and 52.2% were males. There was a statistically significant difference in primary endpoint [time to ablation (56 ± 50.9 days vs 183.3 ± 109.5 days; P < 0.001), time to anticoagulation initiation (2.1 ± 1.6 days vs 19.7 ± 35 days, P < 0.001), antiarrhythmic drug initiation (4.8 ± 7.1 days vs 24.7 ± 44.4 days, P < 0.001) compared to the control group, respectively. As such, this resulted in reduced length of stay in the ER2EP group compared to the control group (2.4 ± 1.4 days vs 3.23 ± 2.5 days, P = 0.002).

Conclusions

This study provides evidence that having an organized pathway from the emergency department for AF patients involving electrophysiology services can improve early access to definitive therapies and clinical outcomes.

Aggressive Rhythm Control Strategy in Atrial Fibrillation Patients Presenting at the Emergency Department: The HEROMEDICUS Study Design and Initial Results

Atrial fibrillation has progressively become a more common reason for emergency department visits, representing 0.5% of presenting reasons. Registry data have indicated that about 60% of atrial fibrillation patients who present to the emergency department are admitted, emphasizing the need for more efficient management of atrial fibrillation in the acute phase. Management of atrial fibrillation in the setting of the emergency department varies between countries and healthcare systems. The most plausible reason to justify a conservative rather than an aggressive strategy in the management of atrial fibrillation is the absence of specific guidelines from diverse societies. Several trials of atrial fibrillation treatment strategies, including cardioversion, have demonstrated that atrial fibrillation in the emergency department can be treated safely and effectively, avoiding admission. In the present study, we present the epidemiology and characteristics of atrial fibrillation patients presenting to the emergency department, as well as the impact of diverse management strategies on atrial-fibrillation-related hospital admissions. Lastly, the design and initial data of the HEROMEDICUS protocol will be presented, which constitutes an electrophysiology-based aggressive rhythm control strategy in patients with atrial fibrillation in the emergency department setting.

Effect of an intensive lifestyle intervention on the structural and functional substrate for atrial fibrillation in people with metabolic syndrome

AIMS

To evaluate the effect of an intensive lifestyle intervention (ILI) on the structural and functional cardiac substrate of atrial fibrillation (AF) in overweight or obese people with metabolic syndrome (Mets).

METHODS AND RESULTS

Participants of the PREvención con DIeta MEDiterranea-Plus trial (n = 6874) were randomized 1:1 to an ILI programme based on an energy-reduced Mediterranean diet, increased physical activity, and cognitive-behavioural weight management or to a control intervention of low-intensity dietary advice. A core echocardiography lab evaluated left atrial (LA) strain, function, and volumes in 534 participants at baseline, 3-year, and 5-year follow-ups. Mixed models were used to evaluate the effect of the ILI on LA structure and function. In the subsample, the baseline mean age was 65 years [standard deviation (SD) 5 years], and 40% of the participants were women. The mean weight change after 5 years was -3.9 kg (SD 5.3 kg) in the ILI group and -0.3 kg (SD 5.1 kg) in the control group. Over the 5-year period, both groups experienced a worsening of LA structure and function, with increases in LA volumes and stiffness index and decreases in LA longitudinal strain, LA function index, and LA emptying fraction over time. Changes in the ILI and control groups were not significantly different for any of the primary outcomes {LA emptying fraction: -0.95% [95% confidence interval (CI) -0.93, -0.98] in the control group, -0.97% [95% CI -0.94, -1.00] in the ILI group, Pbetween groups = 0.80; LA longitudinal strain: 0.82% [95% CI 0.79, 0.85] in the control group, 0.85% [95% CI 0.82, 0.89] in the ILI group, Pbetween groups = 0.24} or any of the secondary outcomes.

CONCLUSION

In overweight or obese people with Mets, an ILI had no impact on the underlying structural and functional LA substrate measurements associated with AF risk.

Pulmonary vein dose and risk of atrial fibrillation in patients with non-small cell lung cancer following definitive radiotherapy: An NI-HEART analysis

BACKGROUND AND PURPOSE

Symptomatic arrhythmia is common following radiotherapy for non-small cell lung cancer (NSCLC), frequently resulting in morbidity and hospitalization. Modern treatment planning technology theoretically allows sparing of cardiac substructures. Atrial fibrillation (AF) comprises the majority of post-radiotherapy arrhythmias, but efforts to prevent this cardiotoxicity have been limited as the causative cardiac substructure is not known. In this study we investigated if incidental radiation dose to the pulmonary veins (PVs) is associated with AF.

MATERIAL AND METHODS

A single-centre study of patients completing contemporary (chemo)radiation for NSCLC, with modern planning techniques. Oncology, cardiology and death records were examined, and AF events were verified by a cardiologist. Cardiac substructures were contoured on planning scans for retrospective dose analysis.

RESULTS

In 420 eligible patients with NSCLC treated with intensity-modulated (70%) or 3D-conformal (30%) radiotherapy with a median OS of 21.8 months (IQR 10.8-35.1), there were 26 cases of new AF (6%). All cases were grade 3 except two cases of grade 4. Dose metrics for both the left (V55) and right (V10) PVs were associated with the incidence of new AF. Metrics remained statistically significant after accounting for the competing risk of death and cardiovascular covariables for both the left (HR 1.02, 95%CI 1.00-1.03, p = 0.005) and right (HR 1.01 (95%CI 1.00-1.02, p = 0.033) PVs.

CONCLUSION

Radiation dose to the PVs during treatment of NSCLC was associated with the onset of AF. Actively sparing the PVs during treatment planning could reduce the incidence of AF during follow-up, and screening for AF may be warranted for select cases.

Implications for neutrophils in cardiac arrhythmias

Cardiac arrhythmias commonly occur as a result of aberrant electrical impulse formation or conduction in the myocardium. Frequently discussed triggers include underlying heart diseases such as myocardial ischemia, electrolyte imbalances, or genetic anomalies of ion channels involved in the tightly regulated cardiac action potential. Recently, the role of innate immune cells in the onset of arrhythmic events has been highlighted in numerous studies, correlating leukocyte expansion in the myocardium to increased arrhythmic burden. Here, we aim to call attention to the role of neutrophils in the pathogenesis of cardiac arrhythmias and their expansion during myocardial ischemia and infectious disease manifestation. In addition, we will elucidate molecular mechanisms associated with neutrophil activation and discuss their involvement as direct mediators of arrhythmogenicity.

Sex-based differences in obstructive sleep apnea and atrial fibrillation: Implication of atrial fibrillation burden

Background

Obstructive sleep apnea (OSA) is a risk factor for atrial fibrillation (AF); however, it is unclear whether AF increases the risk of OSA. Furthermore, sex differences among patients with both AF and OSA remain unclear. We aimed to determine the association between an increased AF burden and OSA and investigate the differences in clinical characteristics between women and men with AF and OSA.

Methods

This was a descriptive, cross-sectional analysis from a prospective cohort study. Patients with non-valvular AF were recruited from the cardiac electrophysiology clinic of a tertiary center; they underwent a home sleep apnea test and 14-day ambulatory electrocardiography. Moderate-to-severe OSA was defined as an apnea-hypopnea index of ≥15.

Results

Of 320 patients with AF, 53.4% had moderate-to-severe OSA, and the mean body mass index (BMI) was 25.6 kg/m2. Less women (38.2%) had moderate-to-severe OSA than men (59.3%) (p < 0.001). In the multivariate analysis, age, being a man, and BMI were significantly associated with moderate-to-severe OSA. AF burden was associated with moderate-to-severe OSA only in men (odds ratio: 1.008; 95% confidence interval: 1.001-1.014). Women and men with OSA had similar BMI (p = 0.526) and OSA severity (p = 0.754), but women were older than men (70.1 ± 1.3 vs. 63.1 ± 0.9 years, p < 0.001). Women with moderate-to-severe OSA had a lower AF burden than men did (27.6 ± 7.1 vs. 49.5 ± 3.9%, p = 0.009).

Conclusions

AF burden is a sex-specific risk factor for OSA and is limited to men. In contrast, women with both AF and OSA have a lower AF burden than men, despite being older and having similar OSA severity and body habitus. Thus, AF may develop later in women with OSA than in men.

Sex Differences in High-Cost Users of Healthcare for Atrial Fibrillation

Background

Healthcare resource use for atrial fibrillation (AF) is high, but it may not be equivalent across all patients. We examined whether sex differences exist for AF high-cost users (HCUs), who account for the top 10% of total acute care costs.

Methods

All patients aged ≥ 20 years who presented to the emergency department (ED) or were hospitalized with AF were identified in Alberta, Canada, between 2011 and 2015. The cohort was categorized by sex into HCUs and non-HCUs. Healthcare utilization was defined as ED, hospital, and physician visits, and costs included those for hospitalization, ambulatory care, physician billing, and drugs. All costs were inflated to 2022 Canadian dollars (CAD$).

Results

Among 48,030 AF patients, 45.1% were female. Of these, 31.8% were HCUs, and the proportions of female and male patients were equal (31.9% vs 31.7%). Female HCUs were older, more likely to have hypertension and heart failure, and had a higher stroke risk than male HCUs. Mean healthcare utilization did not differ among HCUs by sex, except for number of ED visits, which was higher in male patients (12.7% vs 9.2%, P < 0.0001). Overall, HCUs accounted for 65.8% of the total costs (CAD$3.4 billion). Almost half of total HCU costs were attributable to female HCUs (CAD$966.1 million). Significant differences were present in the distributions of HCU-related costs (male patients: 74.6% hospitalization, 9.5% ambulatory care, 12.4% physician billing, 3.5% drugs; female patients: 77.7% hospitalization, 7.4% ambulatory care, 11.5% physician billing, 3.5% drugs, P < 0.0001).

Conclusions

Despite having a lower AF prevalence, female patients represent an equal proportion of HCUs, and account for almost half the total HCU costs. Interventions targeted at reducing the number of AF HCU are needed, particularly for female patients.

AI-enabled Left Atrial Volumetry in Cardiac CT Scans Improves CHARGE-AF and Outperforms NT-ProBNP for Prediction of Atrial Fibrillation in Asymptomatic Individuals: Multi-Ethnic Study of Atherosclerosis

Background

Coronary artery calcium (CAC) scans contain actionable information beyond CAC scores that is not currently reported.

Methods

We have applied artificial intelligence-enabled automated cardiac chambers volumetry to CAC scans (AI-CAC), taking on average 21 seconds per CAC scan, to 5535 asymptomatic individuals (52.2% women, ages 45-84) that were previously obtained for CAC scoring in the baseline examination (2000-2002) of the Multi-Ethnic Study of Atherosclerosis (MESA). We used the 5-year outcomes data for incident atrial fibrillation (AF) and compared the time-dependent AUC of AI-CAC LA volume with known predictors of AF, the CHARGE-AF Risk Score and NT-proBNP (BNP). The mean follow-up time to an AF event was 2.9±1.4 years.

Results

At 1,2,3,4, and 5 years follow-up 36, 77, 123, 182, and 236 cases of AF were identified, respectively. The AUC for AI-CAC LA volume was significantly higher than CHARGE-AF or BNP at year 1 (0.836, 0.742, 0.742), year 2 (0.842, 0.807,0.772), and year 3 (0.811, 0.785, 0.745) (p<0.02), but similar for year 4 (0.785, 0.769, 0.725) and year 5 (0.781, 0.767, 0.734) respectively (p>0.05). AI-CAC LA volume significantly improved the continuous Net Reclassification Index for prediction of AF over years 1-5 when added to CAC score (0.74, 0.49, 0.53, 0.39, 0.44), CHARGE-AF Risk Score (0.60, 0.28, 0.32, 0.19, 0.24), and BNP (0.68, 0.44, 0.42, 0.30, 0.37) respectively (p<0.01).

Conclusion

AI-CAC LA volume enabled prediction of AF as early as one year and significantly improved on risk classification of CHARGE-AF Risk Score and BNP.

Emergency medicine updates: Atrial fibrillation with rapid ventricular response

INTRODUCTION

Atrial fibrillation (AF) may lead to stroke, heart failure, and death. When AF occurs in the context of a rapid ventricular rate/response (RVR), this can lead to complications, including hypoperfusion and cardiac ischemia. Emergency physicians play a key role in the diagnosis and management of this dysrhythmia.

OBJECTIVE

This paper evaluates key evidence-based updates concerning AF with RVR for the emergency clinician.

DISCUSSION

Differentiating primary and secondary AF with RVR and evaluating hemodynamic stability are vital components of ED assessment and management. Troponin can assist in determining the risk of adverse outcomes, but universal troponin testing is not required in patients at low risk of acute coronary syndrome or coronary artery disease - especially patients with recurrent episodes of paroxysmal AF that are similar to their prior events. Emergent cardioversion is indicated in hemodynamically unstable patients. Rate or rhythm control should be pursued in hemodynamically stable patients. Elective cardioversion is a safe option for select patients and may reduce AF symptoms and risk of AF recurrence. Rate control using beta blockers or calcium channel blockers should be pursued in those with AF with RVR who do not undergo cardioversion. Anticoagulation is an important component of management, and several tools (e.g., CHA2DS2-VASc) are available to assist with this decision. Direct oral anticoagulants are the first-line medication class for anticoagulation. Disposition can be challenging, and several risk assessment tools (e.g., RED-AF, AFFORD, and the AFTER (complex, modified, and pragmatic) scores) are available to assist with disposition decisions.

CONCLUSION

An understanding of the recent updates in the literature concerning AF with RVR can assist emergency clinicians in the care of these patients.

Trends in Atrial Fibrillation Management-Results from a National Multi-Center Urgent Care Network Registry

BACKGROUND

Atrial fibrillation (AF) is a common diagnosis in patients presenting to urgent care centers (UCCs), yet there is scant research regarding treatment in these centers. While some of these patients are managed within UCCs, some are referred for further care in an emergency department (ED).

OBJECTIVES

We aimed to identify the rate of patients referred to an ED and define predictors for this outcome. We analyzed the rates of AF diagnosis and hospital referral over the years. Finally, we described trends in patient anticoagulation (AC) medication use.

METHODS

This retrospective study included 5873 visits of patients over age 18 visiting the TEREM UCC network with a diagnosis of AF over 11 years. Multivariate analysis was used to identify predictors for ED referral.

RESULTS

In a multivariate model, predictors of referral to an ED included vascular disease (OR 1.88 (95% CI 1.43-2.45), p < 0.001), evening or night shifts (OR 1.31 (95% CI 1.11-1.55), p < 0.001; OR 1.68 (95% CI 1.32-2.15), p < 0.001; respectively), previously diagnosed AF (OR 0.31 (95% CI 0.26-0.37), p < 0.001), prior treatment with AC (OR 0.56 (95% CI 0.46-0.67), p < 0.001), beta blockers (OR 0.63 (95% CI 0.52-0.76), p < 0.001), and antiarrhythmic medication (OR 0.58 (95% CI 0.48-0.69), p < 0.001). Visits diagnosed with AF increased over the years (p = 0.030), while referrals to an ED decreased over the years (p = 0.050). The rate of novel oral anticoagulant prescriptions increased over the years.

CONCLUSIONS

The rate of referral to an ED from a UCC over the years is declining but remains high. Referrals may be predicted using simple clinical variables. This knowledge may help to reduce the burden of hospitalizations.

Implementation of an integrated emergency department acute atrial fibrillation pathway safely reduces cardioversions and hospitalisations: A comparative pre-post study

OBJECTIVE

Atrial fibrillation/flutter (AF/AFL) accounts for high rates of ED presentations and hospital admissions. There is increasing evidence to suggest that delaying cardioversion for acute uncomplicated AF is safe, and that many patients will spontaneously revert to sinus rhythm (SR). We conducted a before-and-after evaluation of AF/AFL management after a change in ED pathway using a conservative 'rate-and-wait' approach, incorporating next working day outpatient clinic follow-up and delayed cardioversion if required.

METHODS

We performed a before-and-after retrospective cohort study examining outcomes for patients who presented to the ED in Christchurch, New Zealand, with acute uncomplicated AF/AFL in the 1-year period before and after the implementation of a new conservative management pathway.

RESULTS

A total of 360 patients were included in the study (182 'Pre-pathway' vs 178 'Post-Pathway'). Compared to the pre-pathway cohort, those managed under the new pathway had an 81.2% reduction in ED cardioversions (n = 32 vs n = 6), and 50.7% reduction in all cardioversions (n = 65 vs n = 32). There was a 31.6% reduction in admissions from ED (n = 54 vs n = 79). ED length of stay (3.9 h vs 3.8 h, net difference -0.1 h, 95% confidence interval [CI] -0.6 to 0.3), 1-year ED AF representation (32.4% vs 26.4%, net difference -6.0% [95% CI -16.0% to 3.9%]), 1-year ED ischaemic stroke presentation (2.2% in both groups) and 7-day all-cause mortality rates (hazard ratio 1.05 [95% CI 0.6 to 1.9]) were all similar.

CONCLUSIONS

Using a conservative 'rate-and-wait' strategy with early follow-up for patients presenting to ED with AF/AFL can safely reduce unnecessary cardioversions and avoidable hospitalisations.

Effect of PCSK9 Monoclonal Antibody Versus Placebo/Ezetimibe on Atrial Fibrillation in Patients at High Cardiovascular Risk: A Meta-Analysis of 26 Randomized Controlled Trials

BACKGROUND

Patients at high cardiovascular risk are closely associated with an increased risk of atrial fibrillation (AF). Whether proprotein convertase subtilisin/kexin type 9 monoclonal antibodies (PCSK9 mAbs) can attenuate AF progression remains unknown.

METHODS

To compare PCSK9 mAbs with placebo or ezetimibe to explore the effect of PCSK9 mAbs therapy on the end-point of incidence of AF, we searched PubMed, Embase, and ClinicalTrials.gov for articles. We used Mantel-Haenszel risk ratio (RR) with corresponding 95% CI for the categorical data, including the incidence of AF and predefined other outcomes of interest.

RESULTS

We included 21 articles consisting of 26 randomized controlled trials with a total of 95,635 participants. Quantitative synthesis revealed that PCSK9 mAbs significantly reduce the incidence of AF events (RR 0.84; 95% CI 0.72-0.98; p = 0.03), whereas no obvious differences were seen between the PCSK9 mAbs group and the ezetimibe group (RR 0.90; 95% CI 0.29-2.76; p = 0.85). PCSK9 mAbs also markedly decreased the incidence of cerebrovascular events (RR 0.75; 95% CI 0.66-0.85; p < 0.0001) and new-onset hypertension (RR 0.92; 95% CI 0.87-0.97; p = 0.003), but not the risk of cardiovascular death (RR 0.95; 95% CI 0.85-1.07; p = 0.40) and new-onset diabetes mellitus (RR 1.01; 95% CI 0.95-1.08; p = 0.67).

CONCLUSIONS

Overall, the PCSK9 mAbs therapy reduced AF and presented certain cardiovascular benefits in patients at high cardiovascular risk. Further big-scale and long follow-up duration randomized controlled trials that compare PCSK9 mAbs with ezetimibe are required to evaluate the effect of PCSK9 mAbs versus ezetimibe on AF.

Strategies to mitigate emergency department crowding and its impact on cardiovascular patients

Emergency department (ED) crowding is a worsening global problem caused by hospital capacity and other health system challenges. While patients across a broad spectrum of illnesses may be affected by crowding in the ED, patients with cardiovascular emergencies-such as acute coronary syndrome, malignant arrhythmias, pulmonary embolism, acute aortic syndrome, and cardiac tamponade-are particularly vulnerable. Because of crowding, patients with dangerous and time-sensitive conditions may either avoid the ED due to anticipation of extended waits, leave before their treatment is completed, or experience delays in receiving care. In this educational paper, we present the underlying causes of crowding and its impact on common cardiovascular emergencies using the input-throughput-output process framework for patient flow. In addition, we review current solutions and potential innovations to mitigate the negative effect of ED crowding on patient outcomes.

Effect of an intensive lifestyle intervention on the structural and functional substrate for atrial fibrillation in people with metabolic syndrome

Aims

To evaluate the effect of an intensive lifestyle intervention (ILI) on the structural and functional cardiac substrate of atrial fibrillation (AF) in overweight or obese people with metabolic syndrome (MetS).

Methods

Participants of the PREDIMED-PLUS trial (n=6874) were randomised 1:1 to an ILI program based on an energy-reduced Mediterranean diet, increased physical activity, and cognitive-behavioural weight management, or to a control intervention of low-intensity dietary advice. Left atrial (LA) strain, function, and volumes were evaluated by a core echocardiography lab in 534 participants at baseline, 3-year and 5-year follow-up. Mixed models were used to evaluate the effect of the ILI on LA structure and function.

Results

In the subsample, baseline mean age was 65 years (SD 5 years), and 40% of the participants were women. Over the 5-year period, both groups experienced worsening of LA structure and function, with increases in LA volumes and stiffness index and decreases in LA longitudinal strain, LA function index and LA emptying fraction over time. Changes in the ILI and control group were not significantly different for any of the primary outcomes (LA emptying fraction: -0.95% (95%CI -0.93, -0.98) in control group, -0.97% (95%CI -0.94, -1.00) in ILI group, p between groups =0.80; LA longitudinal strain: 0.82% (95%CI 0.79, 0.85) in control group, 0.85% (95%CI 0.82, 0.89) in ILI group, p between groups =0.24) or any of the secondary outcomes.

Conclusions

In overweight or obese people with MetS, an ILI had no impact on the underlying structural and functional left atrial substrate measurements associated with AF risk.

Mobile electrocardiographic devices and healthcare utilization in post-atrial fibrillation ablation patients

BACKGROUND

The use of mobile electrocardiogram (mECG) devices is becoming more prevalent. mECG devices allow instant access to recording arrhythmias and enable automatic rhythm interpretation. Providers can remotely evaluate patients and this may reduce in-person healthcare utilization. We sought to evaluate the utility of mECG devices in reducing healthcare utilization among patients who underwent atrial fibrillation (AF) ablation.

METHODS

We identified a population of patients with paroxysmal or persistent AF presenting for their first AF ablation. Patients were divided into two groups: KardiaMobile (AliveCor, Mountain View, CA) mECG users and non-KardiaMobile users. Healthcare utilization was compared between the two groups for one year post-ablation.

RESULTS

184 patients were studied (76 KardiaMobile users, 108 non-KardiaMobile users). There was no difference in the number of office visits (p = 0.59), cardiac-specific emergency department visits (p = 0.26), cardiac-specific hospital admissions (p = 0.13), ablations or cardioversions completed (p = 0.24), telephone encounters (p = 0.05), patient electronic health record messages (p = 0.40), or cardiac imaging (transthoracic or transesophageal echocardiograms) tests ordered (p = 0.36). Exposure to the device was associated with a reduction in ambulatory cardiac monitor use (p = 0.04). There was no difference in sinus rhythm maintenance over 12 months by Kaplan-Meier survival analysis (log rank test p = 0.05) between groups.

CONCLUSION

Mobile technology is available for heart rhythm monitoring and can give instant feedback to the user. mECG use is associated with a significant reduction in ambulatory cardiac monitor use in the post-ablation period. There was no difference in other AF-related healthcare utilization.

Assessment of atrial fibrillation in European emergency departments: insights from a prospective observational multicenter study

BACKGROUND

The diagnosis and management of atrial fibrillation (AF) in emergency departments (EDs) have not been well described in France, with limited EU research. This study aimed to describe the diagnosis, management, and prognosis of AF patients in French EDs.

METHODS

A prospective, observational 2-month study in adults diagnosed with AF was conducted at 32 French EDs. Data regarding patient characteristics, diagnosis, and treatment at EDs were collected, with 12-month follow-up.

RESULTS

The study included a total of 1369 patients diagnosed with AF at an ED: 279 patients (20.4%) with idiopathic AF (no identified cause of the AF) and 1090 (79.6%) with secondary AF (with a principal diagnosis identified as the cause of AF). Patients were aged 84 years (median) and 51.3% were female. Significantly more idiopathic AF patients than secondary AF patients underwent CHA<inf>2</inf>DS<inf>2</inf>-VASc assessment (67.8% vs. 52.1%,) or echocardiography (21.2% vs. 8.3%), or received an oral anticoagulant and/or antiarrhythmic (62.0% vs. 12.9%). Idiopathic AF patients also had significantly higher rates of discharge to home (36.4% vs. 20.4%) and 3-month cardiologist follow-up (67.0% vs. 41.1%). At 12 months, 96% of patients with follow-up achieved sinus rhythm. The estimated Kaplan-Meier 12-month mortality rate was significantly lower with idiopathic AF than secondary AF (11.9% vs. 34.5%).

CONCLUSIONS

Patients diagnosed with idiopathic or secondary AF at the ED presented heterogeneous characteristics and prognoses, with those with secondary AF having worse outcomes. Further studies are warranted to optimize patients' initial evaluation in EDs and provide appropriate follow-up.

Strategies for rate and rhythm control of atrial fibrillation in the ED

ABSTRACT

Atrial fibrillation (AF) is one of the most common dysrhythmias managed in the ED and accounts for more than half a million visits a year in the United States. More than 6 out of 10 of these visits result in admissions. As the prevalence of AF has continued to increase in recent years, so has the presentation of patients with AF to the ED. For these reasons, clinicians in emergency settings must be knowledgeable of evidence-based rate and rhythm control strategies for stabilizing patients and preventing complications. This article discusses options, indications, contraindications, and safe implementation of rate and rhythm control strategies for ED clinicians. Recent studies have suggested that early rhythm control may benefit newly diagnosed patients, reducing stroke risk, cardiovascular deaths, and disease progression.

Rationale and Design of a Randomized Controlled Clinical Trial on the Safety and Efficacy of Flecainide versus Amiodarone in the Cardioversion of Atrial Fibrillation at the Emergency Department in Patients with Coronary Artery Disease (FLECA-ED)

Pharmacologic cardioversion is a well-established alternative to electric cardioversion for hemodynamically stable patients, as it skips the risks associated with anesthesia. A recent network meta-analysis identifies the most effective antiarrhythmics for pharmacologic cardioversion with flecainide exhibiting a more efficacious and safer profile towards faster cardioversion. Moreover, the meta-analysis of class Ic antiarrhythmics revealed an absence of adverse events when used for pharmacologic cardioversion of AF in the ED, including patients with structural heart disease. The primary goals of this clinical trial are to prove the superiority of flecainide over amiodarone in the successful cardioversion of paroxysmal atrial fibrillation in the Emergency Department and to prove that the safety of flecainide is non-inferior to amiodarone in patients with coronary artery disease without residual ischemia, and an ejection fraction over 35%. The secondary goals of this study are to prove the superiority of flecainide over amiodarone in the reduction in hospitalizations from the Emergency Department due to atrial fibrillation in the time taken to achieve cardioversion, and in the reduction in the need to conduct electrical cardioversion.

ANMCO-SIMEU consensus document: appropriate management of atrial fibrillation in the emergency department

Atrial fibrillation (AF) accounts for 2% of the total presentations to the emergency department (ED) and represents the most frequent arrhythmic cause for hospitalization. It steadily increases the risk of thromboembolic events and is often associated with several comorbidities that negatively affect patient's quality of life and prognosis. AF has a considerable impact on healthcare resources, making the promotion of an adequate and coordinated management of this arrhythmia necessary in order to avoid clinical complications and to implement the adoption of appropriate technological and pharmacological treatment options. AF management varies across regions and hospitals and there is also heterogeneity in the use of anticoagulation and electric cardioversion, with limited use of direct oral anticoagulants. The ED represents the first access point for early management of patients with AF. The appropriate management of this arrhythmia in the acute setting has a great impact on improving patient's quality of life and outcomes as well as on rationalization of the financial resources related to the clinical course of AF. Therefore, physicians should provide a well-structured clinical and diagnostic pathway for patients with AF who are admitted to the ED. This should be based on a tight and propositional collaboration among several specialists, i.e. the ED physician, cardiologist, internal medicine physician, anesthesiologist. The aim of this ANMCO-SIMEU consensus document is to provide shared recommendations for promoting an integrated, accurate, and up-to-date management of patients with AF admitted to the ED or Cardiology Department, in order to make it homogeneous across the national territory.

Clinical decision support to Optimize Care of patients with Atrial Fibrillation or flutter in the Emergency department: protocol of a stepped-wedge cluster randomized pragmatic trial (O'CAFÉ trial)

BACKGROUND

Management of adults with atrial fibrillation (AF) or atrial flutter in the emergency department (ED) includes rate reduction, cardioversion, and stroke prevention. Different approaches to these components of care may lead to variation in frequency of hospitalization and stroke prevention actions, with significant implications for patient experience, cost of care, and risk of complications. Standardization using evidence-based recommendations could reduce variation in management, preventable hospitalizations, and stroke risk.

METHODS

We describe the rationale for our ED-based AF treatment recommendations. We also describe the development of an electronic clinical decision support system (CDSS) to deliver these recommendations to emergency physicians at the point of care. We implemented the CDSS at three pilot sites to assess feasibility and solicit user feedback. We will evaluate the impact of the CDSS on hospitalization and stroke prevention actions using a stepped-wedge cluster randomized pragmatic clinical trial across 13 community EDs in Northern California.

DISCUSSION

We hypothesize that the CDSS intervention will reduce hospitalization of adults with isolated AF or atrial flutter presenting to the ED and increase anticoagulation prescription in eligible patients at the time of ED discharge and within 30 days. If our hypotheses are confirmed, the treatment protocol and CDSS could be recommended to other EDs to improve management of adults with AF or atrial flutter.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05009225 .  Registered on 17 August 2021.

Interhospital Variability in Utilization of Cardioversion for Atrial Fibrillation in the Emergency Department

The role for direct current cardioversion (DCCV) in the management of atrial fibrillation (AF) in the emergency department (ED) is unclear. Factors associated with DCCV in current practice are not well described, nor is the variation across patients and institutions. All ED encounters with a primary diagnosis of AF were identified from the Nationwide Emergency Department Sample from 2006 to 2017. The independent association of patient and hospital factors with use of DCCV was assessed using multivariable hierarchical logistic regression. The relative contributions of patient, hospital, and unmeasured hospital factors were assessed using reference effect measures methods. Among 1,280,914 visits to 3,264 EDs with primary diagnosis of AF, 31,422 patients (2.4%) underwent DCCV in the ED. History of stroke (odds ratio [OR] 0.14, 95% confidence interval [CI] 0.09 to 0.22, p <0.001) and dementia (OR 0.14, 95% CI 0.10 to 0.19, p <0.001) was associated with lowest odds of DCCV. Comparing patients more likely to receive DCCV (ninety-fifth percentile) with patients with median risk, the influence of unmeasured hospital factors (OR 14.13, 95% CI 12.55 to 16.09) exceeded the contributions of patient (OR 5.66, 95% CI 5.28 to 6.15) and measured hospital factors (OR 3.89, 95% CI 2.87 to 5.60). In conclusion, DCCV use in the ED varied widely across institutions. Disproportionately large unmeasured hospital variation suggests that presenting hospital is the most determinative factor in the use of DCCV for ED management of AF. Clarification is needed on best practices for management of AF in the ED, including the use of DCCV.

Impact of Socioeconomic Status on Emergency Department Visits in Patients With Atrial Fibrillation: A Nationwide Population-Based Cohort Study

Background Socioeconomic status (SES) differences could influence management and clinical outcomes in patients with atrial fibrillation (AF), reflecting health inequalities. The authors aimed to investigate emergency department (ED) visits in patients with AF according to SES level. Methods and Results The authors performed a cross-sectional analysis of ED visits in patients with nonvalvular AF using the Korean National Health Insurance Service database in 2016. The patients were divided into health premium quartiles and medical aid groups, with quartile 4 the highest SES and medical aid the lowest SES. Among patients with AF, patients who had ≥1 ED visits in 2016 were identified. The prevalence and cause of ED visits, 30- and 90-day mortality, and rehospitalization risk after ED visits were evaluated. Among the total 371 017 AF patients, 99 306 patients visited the ED in 2016. The medical aid group showed the highest ED visit rate (n=11 833, 38.0%), and patients with the highest quartile of SES (quartile 4 group) showed the lowest ED visit rate (n=38 037, 30.0%). The most common cause of ED visits was cerebral infarction in all groups. The 30- and 90-day mortality rates and rehospitalization risk after ED visits was higher in groups with lower SES. Conclusions Patients with AF and with lower SES had a higher risk of ED visit rate, higher 30- and 90-day mortality rates, and rehospitalization risk after ED visit. Tailored AF management according to different SES levels in patients with AF is needed to improve clinical outcomes.

Breaking the Cycle of Heart Failure With Preserved Ejection Fraction and Atrial Fibrillation

Heart failure with preserved ejection fraction (HFpEF) and AF are two common cardiovascular conditions that are inextricably linked to each other's development and progression, often in multimorbid patients. Current management is often directed to specific components of each disease without considering their joint impact on diagnosis, treatment and prognosis. The result for patients is suboptimal on all three levels, restricting clinicians from preventing major adverse events, including death, which occurs in 20% of patients at 2 years and in 45% at 4 years. New trial evidence and reanalysis of prior trials are providing a glimmer of hope that adverse outcomes can be reduced in those with concurrent HFpEF and AF. This will require a restructuring of care to integrate heart failure and AF teams, alongside those that manage comorbidities. Parallel commencement and non-sequential uptitration of therapeutics across different domains will be vital to ensure that all patients benefit at a personal level, based on their own needs and priorities.

Development of a Care Pathway for Atrial Fibrillation Patients in the Emergency Department

Atrial fibrillation (AF) is the most common cardiac arrhythmia and its prevalence is continuously increasing in the United States, leading to a progressive rise in the number of disease-related emergency department (ED) visits and hospitalizations. Although optimal long-term outpatient management for AF is well defined, the guidelines for optimal ED management of acute AF episodes is less clear. Studies have demonstrated that discharging patients with AF from the ED after acute stabilization is both safe and cost effective; however, the majority of these patients in the United States and in our institution are admitted to the hospital. To improve care of these patients, we established a multidisciplinary collaboration to develop an evidence-based systematic approach for the treatment and management of AF in the ED, that led to the creation of the University of California-Cardioversion, Anticoagulation, Rate Control, Expedited Follow-up/Education Atrial Fibrillation Pathway. Our pathway focuses on the acute stabilization of AF, adherence to best practices for anticoagulation, and reduction in unnecessary admissions through discharge from the ED with expedited outpatient follow-up whenever safe. A novel aspect of our pathway is that it is primarily driven by the ED physicians, while other published protocols primarily involve consulting cardiologists to guide management in the ED. Our protocol is very pertinent considering the current trend toward increased AF prevalence in the United States, coupled with a need for widespread implementation of strategies aimed at improving management of these patients while safely reducing hospital admissions and the economic burden of AF.

Trends in Uptake and Adherence to Oral Anticoagulation for Patients With Incident Atrial Fibrillation at High Stroke Risk Across Health Care Settings

Background

Oral anticoagulation (OAC) therapy prevents morbidity and mortality in nonvalvular atrial fibrillation; whether location of diagnosis influences OAC uptake or adherence is unknown.

Methods and Results

Retrospective cohort study (2008–2019), identifying adults with incident nonvalvular atrial fibrillation across health care settings (emergency department, hospital, outpatient) at high risk of stroke. OAC uptake and adherence via proportion of days covered for direct OACs and time in therapeutic range for warfarin were measured. Proportion of days covered was categorized as low (0–39%), intermediate (40–79%), and high (80–100%). Warfarin control was defined as time in therapeutic range ≥65%. All‐cause mortality was examined at a 3‐year landmark. Among 75 389 patients with nonvalvular atrial fibrillation (47.0% women, mean 77.4 years), 19.7% were diagnosed in the emergency department, 59.1% in the hospital, and 21.2% in the outpatient setting. Ninety‐day OAC uptake was 51.6% in the emergency department, 50.9% in the hospital, and 67.9% in the outpatient setting (P<0.0001). High direct OAC adherence increased from 64.9% to 80.3% in the emergency department, 64.3% to 81.7% in the hospital, and 70.9% to 88.6% in the outpatient setting over time (P values for trend <0.0001). Warfarin control was 40.3% overall and remained unchanged. In multivariable analysis, outpatient diagnosis compared with the hospital was associated with greater OAC uptake (odds ratio [OR], 1.79; [95% CI, 1.72–1.87]) and direct OAC (OR, 1.42; [95% CI, 1.27–1.59]) and warfarin (OR, 1.49; [95% CI, 1.36–1.63]) adherence. Varying or persistently low adherence was associated with a poor prognosis, especially for warfarin.

Conclusions

Locale of nonvalvular atrial fibrillation diagnosis is associated with varying OAC uptake and adherence. Interventions specific to health care settings are needed to improve stroke prevention.

Telemedicine practices in adult patients with atrial fibrillation

BACKGROUND

Atrial fibrillation is a cardiac rhythm disorder associated with embolic stroke risk, decreased functional capacity, and worsening quality of life. Increasing patient access to atrial fibrillation specialists via telemedicine has the potential to improve patient outcomes.

OBJECTIVES

The purpose of this systematic review was to describe atrial fibrillation telehealth education treatment programs unrelated to postablation or early detection of atrial fibrillation.

DATA SOURCES

PubMed and CINAHL databases were searched using key terms identified by the authors and informed by a panel of clinicians with expertise in cardiac electrophysiology.

CONCLUSIONS

Little literature exists on educational telehealth programs for atrial fibrillation treatment unrelated to postablation or early detection of atrial fibrillation. Only three studies met our inclusion criteria. Three themes emerged from review of these studies: (a) atrial fibrillation requires specialty care that is difficult to obtain; (b) comprehensive atrial fibrillation education should include a broad overview of the condition, management options, stroke prevention, and symptom management; and (c) telemedicine is effective for diagnosing and managing atrial fibrillation.

IMPLICATIONS FOR PRACTICE

Telemedicine clinics for atrial fibrillation represent an emerging form of clinically important health care delivery. These clinics can potentially decrease wait time for specialty care access, reduce unnecessary emergency department visits, reduce stroke risk, and increase guideline adherence. Nurse practitioners are well suited to create and lead telemedicine atrial fibrillation clinics with relevant clinical expertise and collaborative skills.

The Palma Echo Platform: Rationale and Design of an Echocardiography Core Lab

Background

The metabolic syndrome (MetS) is associated with increased cardiovascular morbidity and mortality. Characterization of cardiac structural and functional abnormalities due to the MetS can help recognize individuals who would benefit the most from preventive interventions. Transthoracic echocardiography (TTE) provides an opportunity to identify those abnormalities in a reproducible and cost-efficient manner. In research settings, implementation of protocols for the acquisition and analysis of TTE images are key to ensure validity and reproducibility, thus facilitating answering relevant questions about the association of the MetS with cardiac alterations.

Methods and Results

The Palma Echo Platform (PEP) is a coordinated network that is built up to evaluate the underlying structural and functional cardiac substrate of participants with MetS. Repeated TTE will be used to evaluate 5-year changes in the cardiac structure and function in a group of 565 individuals participating in a randomized trial of a lifestyle intervention for the primary prevention of cardiovascular disease. The echocardiographic studies will be performed at three study sites, and will be centrally evaluated at the PEP core laboratory. Planned analyses will involve evaluating the effect of the lifestyle intervention on cardiac structure and function, and the association of the MetS and its components with changes in cardiac structure and function. Particular emphasis will be placed on evaluating parameters of left atrial structure and function, which have received more limited attention in past investigations. This PEP will be available for future studies addressing comparable questions.

Conclusion

In this article we describe the protocol of a central echocardiography laboratory for the study of functional and structural alterations of the MetS.

Utility of magnesium sulfate in the treatment of rapid atrial fibrillation in the emergency department: a systematic review and meta-analysis

Atrial fibrillation with rapid ventricular response (Afib/RVR) is a frequent reason for emergency department (ED) visits and can be treated with a variety of pharmacological agents. Magnesium sulfate has been used to prevent and treat postoperative Afib/RVR. We performed a systematic review and meta-analysis to assess the effectiveness of magnesium for treatment of Afib/RVR in the ED. PubMed and Scopus databases were searched up to June 2021 to identify any relevant randomized trials or observational studies. We used Cochrane's Risk-of-Bias tools to assess study qualities and random-effects meta-analysis for the difference of heart rate (HR) before and after treatment. Our search identified 395 studies; after reviewing 11 full texts, we included five randomized trials in our analysis. There were 815 patients with Afib/RVR; 487 patients (60%) received magnesium treatment, whereas 328 (40%) patients received control treatment. Magnesium treatment was associated with significant reduction in HR [standardized mean difference (SMD), 0.34; 95% CI, 0.21-0.47; P < 0.001; I2 = 4%), but not associated with higher rates of sinus conversion (OR, 1.46; 95% CI, 0.726-2.94; P = 0.29), nor higher rates of hypotension and bradycardia (OR, 2.2; 95% CI, 0.62-8.09; P = 0.22). Meta-regressions demonstrated that higher maintenance dose (corr. coeff, 0.17; P = 0.01) was positively correlated with HR reductions, respectively. We observed that magnesium infusion can be an effective rate control treatment for patients who presented to the ED with Afib/RVR. Further studies with more standardized forms of control and magnesium dosages are necessary to assess the benefit/risk ratio of magnesium treatment, besides to confirm our observations.

Financial Costs of Emergency Department Presentations for Australian Patients With Heart Disease in the Last 3 Years of Life

Aims:

This study described emergency department (ED) resource use patterns and associated costs among patients with heart disease in their last 3 years of life in a high-income country.

Methods:

This study used linked data from ED and death registry databases in Australia. A random sample of 1000 patients who died due to any cause in 2017, and who had been living with heart disease for at least the prior 10-years were included. The outcomes of interest were number of ED presentations over each of the last 3 years prior to death and relative cost contributions of ED-related items.

Results:

The number of patients needing ED care and number of ED presentations per patient increased as patients were closer to death, with 85% experiencing at least one ED presentation in their last year of life. Mean per patient ED presentation cost increased with each year closer to death. Costs related to labor, pathology, patient travel, and goods and services contributed more than 85% of the total cost in each of the 3 years.

Conclusion:

The increase in cost burden as patients neared death was attributable to more frequent ED presentations per person rather than more expensive ED presentations. The scope of this study was limited to ED presentations, and may not be representative of heart-disease-related end-of-life care more broadly.

Prediction of Successful Pharmacological Cardioversion in Acute Symptomatic Atrial Fibrillation: The Successful Intravenous Cardioversion for Atrial Fibrillation (SIC-AF) Score

Background: Modern personalised medicine requires patient-tailored decisions. This is particularly important when considering pharmacological cardioversion for the acute treatment of haemodynamically stable atrial fibrillation and atrial flutter in a shared decision-making process. We aimed to develop and validate a predictive model to estimate the individual probability of successful pharmacological cardioversion using different intravenous antiarrhythmic agents. Methods: We analysed data from a prospective atrial fibrillation registry comprising 3053 cases of first-detected or recurrent haemodynamically stable, non-permanent, symptomatic atrial fibrillation presenting to an Austrian academic emergency department between January 2012 and December 2017. Using multivariable analysis, a prediction score was developed and externally validated. The clinical utility of the score was assessed using decision curve analysis. Results: A total of 1528 cases were included in the development cohort (median age 69 years, IQR 58−76; 43.9% female), and 1525 cases were included in the validation cohort (median age 68 years, IQR (58−75); 39.5% female). Finally, 421 cases were available for score development and 330 cases for score validation The weighted score included atrial flutter (8 points), duration of symptoms associated with AF (<24 h; 8 points), absence of previous electrical cardioversion (10 points), and the specific intravenous antiarrhythmic drug (amiodarone 10 points, vernakalant 11 points, ibutilide 13 points). The final score, the “Successful Intravenous Cardioversion for Atrial Fibrillation (SIC-AF) score,” showed good calibration (R2 = 0.955 and R2 = 0.954) and discrimination in both sets (c-indices: 0.68 and 0.66) and net clinical benefit. Conclusions: A predictive model was developed to estimate the success of intravenous pharmacological cardioversion using different antiarrhythmic agents in a cohort of patients with haemodynamically stable, non-permanent, symptomatic atrial fibrillation. External temporal validation confirmed good calibration, discrimination, and clinical usefulness. The SIC-AF score may help patients and physicians jointly decide on the appropriate treatment strategy for acute symptomatic atrial fibrillation. Registration: NCT03272620.

Reappraising the role of class Ic antiarrhythmics in atrial fibrillation

PURPOSE

The objective of the present systematic review was to compare the effectiveness and safety of class Ic agents for cardioversion of paroxysmal atrial fibrillation (AF), in patients with and without structural heart disease (SHD).

METHODS

We focused on RCTs enrolling at least 50 adult patients with electrocardiogram-documented paroxysmal AF that compared either two pharmacological class Ic cardioversion agents (flecainide, propafenone), regardless of study design (parallel or crossover). We searched MEDLINE and the Cochrane Central Register of Controlled Trials. Initial search was performed from inception to 15 July 2021 with no language restrictions.

RESULTS

Intravenous flecainide is the most effective option for pharmacologic cardioversion of AF since only 2 patients need to be treated in order to cardiovert one more within 4 h. Most importantly, class Ic agents appear to be safe in the context of pharmacologic cardioversion of AF irrespective of the presence of SHD, pointing towards a possible reappraisal of the role in this setting.

CONCLUSION

We suggest that class Ic agents (with flecainide appearing to be more effective) should be used for pharmacologic cardioversion in stable AF patients presenting in emergency department with unknown medical history, after excluding severe cardiac disease through a bedside examination.

REGISTRATION NUMBER (DOI)

Available in https://osf.io/apwt7/ , https://doi.org/10.17605/OSF.IO/APWT7.

Economics and Outcomes of Sotalol In-Patient Dosing Approaches in Patients with Atrial Fibrillation

Introduction

There exists variability in the administration of in‐patient sotalol therapy for symptomatic atrial fibrillation (AF). The impact of this variability on patient in‐hospital and 30‐day posthospitalization costs and outcomes is not known. Also, the cost impact of intravenous sotalol, which can accelerate drug loading to therapeutic levels, is unknown.

Methods

One hundred and thirty‐three AF patients admitted for oral sotalol initiation at an Intermountain Healthcare Hospital from January 2017 to December 2018 were included. Patient and dosing characteristics were described descriptively and the impact of dosing schedule was correlated with daily hospital costs/clinical outcomes during the index hospitalization and for 30 days. The Centers for Medicare and Medicaid Services reimbursement for 3‐day sotalol initiation is $9263.51. Projections of cost savings were made considering a 1‐day load using intravenous sotalol that costs $2500.00 to administer.

Results

The average age was 70.3 ± 12.3 years and 60.2% were male with comorbidities of hypertension (83%), diabetes (36%), and coronary artery disease (53%). The mean ejection fraction was 59.9 ± 7.8% and the median corrected QT interval was 453.7 ± 37.6 ms before sotalol dosing. No ventricular arrhythmias developed, but bradycardia (<60 bpm) was observed in 37.6% of patients. The average length of stay was 3.9 ± 4.6 (median: 2.2) days. Postdischarge outcomes and rehospitalization rates stratified by length of stay were similar. The cost per day was estimated at $2931.55 (1. $2931.55, 2. $5863.10, 3. $8794.65, 4. $11 726.20).

Conclusions

In‐patient oral sotalol dosing is markedly variable and results in the potential of both cost gain and loss to a hospital. In consideration of estimated costs, there is the potential for $871.55 cost savings compared to a 2‐day oral load and $3803.10 compared to a 3‐day oral load.

Identifying outcome measures for atrial fibrillation value-based contracting using the Delphi method

BACKGROUND

Value-based contracts that tie payments for pharmaceuticals to predefined outcomes aim to promote value through shared risk and aligned incentives between manufacturers and payers.

METHODS

We conducted a Delphi study among diverse stakeholders (patients, providers, payers, pharmacy benefits managers, pharmaceutical company representatives) to identify top meaningful outcomes for inclusion in value-based contracts for atrial fibrillation medications. The final panel (n = 55) rated the importance of each outcome on a 5-point Likert scale and selected their top 3 most meaningful outcomes. Non-patient participants rated the feasibility of collecting each outcome on a 5-point Likert scale. Consensus was defined as ≥75% agreement (Likert scores ≥4/5 or selection of an outcome as most meaningful). Differences between stakeholder groups were examined using Fisher's Exact Test.

RESULTS

Consensus was achieved for importance of 10 outcomes (Likert scale), where "preventing stroke or mini-stroke" reached 100% agreement (55/55). Eighty-one percent (44/54) of participants selected "preventing stroke or mini-stroke" as the most meaningful outcome (rank order question). The measures rated as most feasibly collected were "reducing hospitalizations" (97%, 36/37) followed by "preventing stroke or mini-stroke" and "reducing emergency department visits" (both 92%, 34/37). There were statistically significant differences between patients and non-patients [0% (0/17) vs 22% (8/37), P = 0.047] and patients and providers [0% (0/17) vs 39% (7/18), P = 0.008] in selection of "improving health-related quality of life" as a most meaningful outcome.

CONCLUSIONS

These findings will inform the design of atrial fibrillation value-based pharmaceutical contracts and provide additional insight into preferences for outcomes which could be used to improve the quality of atrial fibrillation care.

Trends and Inpatient Outcomes of Primary Atrial Fibrillation Hospitalizations with Underlying Iron Deficiency Anemia: An Analysis of The National Inpatient Sample Database from 2004 -2018

Atrial fibrillation (AF) is the most prevalent arrhythmia in the United States. However, studies evaluating the impact of iron deficiency anemia on AF outcomes are limited. Therefore, we aimed to evaluate the association of iron deficiency anemia (IDA) on clinical outcomes in patients hospitalized with AF. A retrospective analysis of adult hospital discharges from the National Inpatient Sample (NIS) between 2004 and 2018 was conducted. Multivariable logistic regression was used to assess the association of IDA and other clinical outcomes ie inpatient mortality, acute myocardial infarction, cardiogenic shock, acute kidney injury, vasopressors use, length of stay, and other resource utilization. These models were adjusted for patient and hospital-level characteristics. A total of 5,975,241 weighted primary AF hospitalizations were identified. Out of these, 152,059 (2.5%) had diagnosis of IDA. After adjustment of variables, admissions with IDA were associated with higher rates of acute myocardial infarction (adjusted odds ratio [aOR] = 1.10, 95% CI 1.01-1.19 P = 0.026), use of vasopressors (aOR = 1.30, CI 1.27-1.32, P <0.001), invasive mechanical ventilation (aOR = 1.26, CI 1.14-1.40 P <0.001) and acute kidney injury (aOR = 1.72, CI 1.66-1.79 P <0.001). There was no significant difference in all-cause mortality (aOR = 0.97, CI 0.87-1.07, P = 0.513), cardiogenic shock, in-hospital cardiac arrest or use of mechanical circulatory support. Adjusted mortality in patients with AF and IDA decreased from 1.09% to 0.54% from 2004 to2018 (P -trend < 0.001). Among hospitalized patients with AF, our study did not show any difference in all-cause mortality between those with and without IDA.

LVS-HARMED Risk Score for Incident Heart Failure in Patients With Atrial Fibrillation Who Present to the Emergency Department: Data from a World-Wide Registry

Background Heart failure (HF) is a common complication to atrial fibrillation (AF), leading to rehospitalization and death. Early identification of patients with AF at risk for HF might improve outcomes. We aimed to derive a score to predict 1-year risk of new-onset HF after an emergency department (ED) visit with AF. Methods and Results The RE-LY AF (Randomized Evaluation of Long-Term Anticoagulant Therapy) registry enrolled patients with AF presenting to an ED in 47 countries, and followed them for a year. The end point was HF hospitalization and/or HF death. Among 15 400 ED patients, 9765 had no prior HF (mean age, 64.9±14.9 years). Within 1 year, new-onset HF developed in 6.8% of patients, of whom 21% died of HF. Independent predictors of HF included left ventricular hypertrophy (odds ratio [OR], 1.47; 95% CI, 1.19-1.82), valvular heart disease (OR, 1.55; 95% CI, 1.18-2.04), smoking (OR, 1.42; 95% CI, 1.12-1.78), height (OR, 0.93; 95% CI, 0.90-0.95 per 3 cm), age (OR, 1.11; 95% CI, 1.07-1.15 per 5 years), rheumatic heart disease (OR, 1.77, 95% CI, 1.24-2.51), prior myocardial infarction (OR, 1.85; 95% CI, 1.45-2.36), remaining in AF at ED discharge (OR, 1.86; 95% CI, 1.46-2.36), and diabetes (OR, 1.33; 95% CI, 1.09-1.64). A continuous risk prediction score (LVS-HARMED [left ventricular, valvular heart disease, smoking or other tobacco use, height, age, rheumatic heart disease, myocardial infarction, emergency department discharge rhythm, and diabetes]) had good discrimination (C statistic, 0.735; 95% CI, 0.716-0.755). Validation was conducted internally using bootstrapping (optimism-corrected C statistic, 0.705) and externally (C statistic, 0.699). The 1-year incidence of HF hospitalization and/or HF death across quartile groups of the score was 1.1%, 4.5%, 6.9%, and 14.4%, respectively. LVS-HARMED also predicted incident stroke (C statistic, 0.753; 95% CI, 0.728-0.778). Conclusions The LVS-HARMED score predicts new-onset HF after an ED visit for AF. Preventative strategies should be considered in patients with high LVS-HARMED HF risk.

Mendelian randomization study on atrial fibrillation and cardiovascular disease subtypes

Atrial fibrillation (AF) has been associated with numerous diseases. However, whether AF is a cause or consequence of these diseases is uncertain. To clarify, we assessed the causal role of AF on ischemic heart disease (IHD), stroke, other cardiovascular disease (CVD) subtypes, type 2 diabetes mellitus (T2DM), and late-onset AD using bi-directional two-sample Mendelian randomization (MR) among people primarily of European descent. Genetically predicted log odds of AF was associated with any stroke (odds ratio (OR) 1.22, 95% CI 1.18 to 1.27), particularly cardioembolic stroke and possibly subdural hemorrhage, with sensitivity analyses showing similar positive findings. Genetically predicted AF was also associated with arterial thromboembolism (1.32, 1.13 to 1.53), and heart failure (1.26, 1.21 to 1.30). No association of genetically predicted AF with IHD, T2DM, cognitive function, or late-onset AD was found. Conversely, genetically predicted IHD, heart failure and possibly ischemic stroke, particularly cardioembolic stroke, were positively associated with AF. Atrial fibrillation plays a role in any stroke, arterial thromboembolism, and heart failure, corroborating current clinical guidelines on the importance of preventing these complications by effective AF management. In addition, patients with IHD, heart failure or possibly ischemic stroke might be predisposed to developing AF, with implications for management.

Outcomes of transesophageal echocardiogram-guided electrical cardioversion in patients with atrial fibrillation greater than 48 hours treated in the emergency department versus the cardiology ward: A retrospective comparison study

BACKGROUND

The current emergency medicine literature on cardioversion for atrial fibrillation (AF) describes its performance on those who are hemodynamically unstable, present within 48 hours of the onset of the arrhythmia, or are on long-term anticoagulants. For patients who are not anticoagulated and present with atrial fibrillation for more than 48 hours, one option is to perform a transesophageal echocardiogram and then synchronized cardioversion in the absence of atrial clot. The objective of this study is to compare outcomes of patients presenting to the emergency department (ED) with atrial fibrillation (AF) of more than 48 hours who underwent a transesophageal echocardiogram (TEE) and subsequent cardioversion in the ED versus the cardiology ward.

METHODS

This was a retrospective comparison study of patients who presented to the ED with AF for more than 48 hours, underwent a transesophageal echocardiogram, and then were electrically cardioverted either in the emergency department or in the cardiology ward. Outcomes include: time to cardioversion, length of hospital stay, rate of successful cardioversion, and rate of complications.

RESULTS

Electrical cardioversion was performed in the ED on 94 patients (62%) and the cardiology ward on 57 (38%). Over 90% of cardioversions were successful in both groups. Time to cardioversion was significantly less in the ED group versus the cardiology group (1.04 ± 0.9 days versus 3.81 ± 1.9; P < .001). Similarly, the mean length of hospital stay was less for the ED group (1.6 ± 1.6 days versus 7.3 ± 3.5; P < .001).

CONCLUSION

Patients who present in atrial fibrillation for more than 48 hours and then have a TEE undergo electrical cardioversion faster in the ED compared with the cardiology ward. This clinical pathway also results in a shorter length of hospital stay without having more side effects.

Factors associated with poor prognosis in patients with atrial fibrillation: An emergency department perspective the EMERG-AF study

OBJECTIVE

We sought to identify the factors associated with a worse prognosis in Emergency Department (ED) patients with atrial fibrillation (AF), crucial information to guide management decisions.

METHODS

This is a secondary analysis of a prospective, multicenter, observational cohort of consecutive AF patients attended in 62 EDs in Spain. Clinical variables were collected on enrollment. Follow-up was performed at 30 days and one year. The primary composite outcome was all-cause mortality, major bleeding and/or stroke at one year. Secondary outcomes were each of these components considered separately, plus one-year cardiovascular mortality and the composite outcome at 30 days.

RESULTS

We analyzed 1107 patients. The primary outcome occurred in 209 patients (18.9%), one-year all-cause mortality in 151 (13.6%), major bleeding in 47 (4.2%), and stroke in 31 (2.8%). Disability (HR 2.064, 95% CI 1.478-2.882), previous known AF (HR 1.829, 95% CI 1.096-3.051), long duration of the AF episode (HR 1.849, 95% CI 1.052-3.252) and renal failure (HR 2.073, 95% CI 1.433-2.999) were independently associated with the primary outcome, whereas anticoagulation at discharge was inversely associated (HR 0.576, 95% CI 0.415-0.801). Disability was associated with mortality, cardiovascular mortality, and the composite at 30 days, and renal failure with mortality and major bleeding.

CONCLUSIONS

Comorbidities like renal failure, long AF duration and disability were related to adverse outcomes and should be decisive to guide management decisions in ED patients with AF. Anticoagulation had a positive impact on prognosis and should be the mainstay of therapy in AF patients attended in ED.

Usefulness of Mobile Electrocardiographic Devices to Reduce Urgent Healthcare Visits

Mobile electrocardiogram (mECG) devices are being used increasingly, supplying recordings to providers and providing automatic rhythm interpretation. Given the intermittent nature of certain cardiac arrhythmias, mECGs allow instant access to a recording device. In the current COVID-19 pandemic, efforts to limit in-person patient interactions and avoid overwhelming emergency and inpatient services would add value. Our goal was to evaluate whether a mECG device would reduce healthcare utilization overall, particularly those of urgent nature. We identified a cohort of KardiaMobile (AliveCor, USA) mECG users and compared their healthcare utilization 1 year prior to obtaining the device and 1 year after. One hundred and twenty-eight patients were studied (mean age 64, 47% female). Mean duration of follow-up pre-intervention was 9.8 months. One hundred and twenty-three of 128 individuals completed post-intervention follow-up. Patients were less likely to have cardiac monitors ordered (30 vs 6; p <0.01), outpatient office visits (525 vs 382; p <0.01), cardiac-specific ED visits (51 vs 30; p <0.01), arrhythmia related ED visits (45 vs 20; p <0.01), and unplanned arrhythmia admissions (34 vs 11; p <0.01) in the year after obtaining a KardiaMobile device compared to the year prior to obtaining the device. Mobile technology is available for heart rhythm monitoring and can give feedback to the user. This study showed a reduction of in-person, healthcare utilization with mECG device use. In conclusion, this strategy would be expected to decrease the risk of exposure to patients and providers and would avoid overwhelming emergency and inpatient services.

Early Risk of Stroke in Patients Undergoing Acute Versus Elective Cardioversion for Atrial Fibrillation

Background

Electrical cardioversion (ECV) is routinely used to restore sinus rhythm in patients with symptomatic atrial fibrillation. The European guidelines have been updated in recent years. Current information on differences in the risk for stroke after acute versus elective ECV is lacking.

Methods And Results

All patients with a first‐time acute or elective ECV in the Stockholm regional health care data warehouse from 2011 to 2018 were included. Cox regression analyses were performed evaluating ischemic or unspecified stroke within 30 days after ECV with adjustments for the CHA₂DS₂‐VASc score, medical treatment, and year of inclusion. The study included 9139 patients, 3094 after acute and 6045 after elective ECV. The mean age was 65.9±11.3 years, 69.5% were men, and the mean CHA₂DS₂‐VASc score was 2.4±1.7. Before the intervention, 49.6% of patients with an acute ECV and 96.4% of those with an elective ECV had claimed an oral anticoagulant prescription. Ischemic or unspecified stroke occurred in 26 (0.28%) patients within 30 days. The unadjusted risk was higher after acute compared with elective ECV (hazard ratio [HR], 2.29; 95% CI, 1.06–4.96), whereas there was no difference after multivariable adjustments (adjusted HR, 0.99; 95% CI, 0.36–2.72). Both non–vitamin K oral anticoagulants (adjusted HR, 0.28; 95% CI, 0.08–0.98) and warfarin (adjusted HR, 0.17; 95% CI, 0.05–0.53) were associated with a lower risk for stroke compared with no anticoagulation.

Conclusions

Acute ECV was associated with a higher unadjusted risk for stroke than elective ECV, but the risk was similar after adjustment for anticoagulant treatment. This study indicates the importance of anticoagulation before ECV according to recent European guidelines.

Trends in Emergency Department Utilization Among Women With Leiomyomas in the United States

OBJECTIVE

To describe trends in emergency department (ED) visits in the United States with a primary diagnosis of leiomyomas, subsequent admissions, and associated charges.

METHODS

The Healthcare Cost and Utilization Project Nationwide Emergency Department Sample database was used to retrospectively identify all ED visits from 2006 to 2017 among women aged 18-55 years with a primary diagnosis of leiomyomas as indicated by International Classification of Diseases (ICD) diagnosis codes. Trends in ED visits and subsequent admissions were analyzed and stratified by patient and hospital characteristics. Secondary ICD codes, Current Procedural Terminology codes, and hospital charges were analyzed. A multivariate regression model was used to identify predictors of admission.

RESULTS

Although the number of ED visits for leiomyomas increased from 28,732 in 2006 to 65,685 in 2017, the admission rate decreased, from 23.9% in 2006 to 11.1% in 2017. Emergency department visits for leiomyomas were highest among women who were aged 36-45 years (44.5%), in the lowest income quartile (36.1%), privately insured (38.3%), and living in the South (46.2%). Admission was more likely at nonteaching hospitals (odds ratio [OR] 1.23, 95% CI 1.08-1.39) or those located in the Northeast (OR 1.39, 95% CI 1.15-1.68). Patient characteristics associated with admission included older age (26-35 years: OR 1.42, 95% CI 1.21-1.66; 36-45 years: OR 2.01, 95% CI 1.72-2.34; 46-55 years: OR 2.60, 95% CI 2.23-3.03) and bleeding-related complaints (OR 14.92, 95% CI 14.00-15.90). Admission was least likely in uninsured patients (Medicare: OR 1.37, 95% CI 1.21-1.54; Medicaid: OR 1.26, 95% CI 1.16-1.36; private: OR 1.44, 95% CI 1.32-1.56).

CONCLUSION

Although ED visits for leiomyomas are increasing, admission rates for these visits are decreasing. The substantial decline in admissions suggests many of these visits could potentially be addressed in a non-acute-care setting. However, when women with leiomyomas present with a bleeding-related complaint, the odds of admission increase 15-fold. There is an apparent disparity in likelihood of admission based on insurance type.

RAFF-3 Trial: A Stepped-Wedge Cluster Randomized Trial to Improve Care of Acute Atrial Fibrillation and Flutter in the Emergency Department

BACKGROUND

We sought to improve care of patients with acute atrial fibrillation (AF) and flutter (AFL) in the emergency department (ED) by implementing the CAEP AAFF Best Practice Checklist.

METHODS

We conducted a stepped-wedge cluster randomized trial at 11 large community and academic hospital EDs, in five Canadian provinces and enrolled consecutive AF/AFL patients. The study intervention was the introduction of the CAEP Checklist using a knowledge translation-implementation approach that included behavior change techniques and organization/system level strategies. The primary outcome was length of stay in ED and secondary outcomes were discharge home, use of rhythm control, adverse events, and 30-day status. Analysis used mixed effects regression adjusting for covariates.

RESULTS

Patient visits in the control (N=314) and intervention (N=404) periods were similar with mean age 62.9, 54% male, 71% onset <12 hours, and 86% atrial fibrillation, 14% atrial flutter. We observed a reduction in length of stay of 20.9% (95% CI 5.5 to 33.8%, P=0.01), an increase in use of rhythm control (adjusted odds ratio (OR 4.5, 1.8-11.6; P=0.002), and decrease in use of rate control medications (OR 0.5, 0.2 to 0.9; P=0.02). There was no change in adverse events and no strokes or deaths by 30 days.

CONCLUSIONS

The RAFF-3 Trial led to optimized care of AF/AFL patients with decreased ED lengths of stay, increased ED rhythm control by drug or electricity, and no increase in adverse events. Early cardioversion allows AF/AFL patients to quickly resume normal activities. CLINICALTRIALS.

GOV IDENTIFIER

NCT03627143.

Pharmacologic cardioversion of recent-onset atrial fibrillation: a systematic review and network meta-analysis

AIMS

We sought to identify the most effective antidysrhythmic drug for pharmacologic cardioversion of recent-onset atrial fibrillation (AF).

METHODS AND RESULTS

We searched MEDLINE, Embase, and Web of Science from inception to March 2019, limited to human subjects and English language. We also searched for unpublished data. We limited studies to randomized controlled trials that enrolled adult patients with AF ≤ 48 h and compared antidysrhythmic agents, placebo, or control. We determined these outcomes prior to data extraction: (i) rate of conversion to sinus rhythm within 24 h, (ii) time to cardioversion to sinus rhythm, (iii) rate of significant adverse events, and (iv) rate of thromboembolism within 30 days. We extracted data according to PRISMA-NMA and appraised selected trials using the Cochrane review handbook. The systematic review initially identified 640 studies; 30 met inclusion criteria. Twenty-one trials that randomized 2785 patients provided efficacy data for the conversion rate outcome. Bayesian network meta-analysis using a random-effects model demonstrated that ranolazine + amiodarone intravenous (IV) [odds ratio (OR) 39.8, 95% credible interval (CrI) 8.3-203.1], vernakalant (OR 22.9, 95% CrI 3.7-146.3), flecainide (OR 16.9, 95% CrI 4.1-73.3), amiodarone oral (OR 10.2, 95% CrI 3.1-36.0), ibutilide (OR 7.9, 95% CrI 1.2-52.5), amiodarone IV (OR 5.4, 95% CrI 2.1-14.6), and propafenone (OR 4.1, 95% CrI 1.7-10.5) were associated with significantly increased likelihood of conversion within 24 h when compared to placebo/control. Overall quality was low, and the network exhibited inconsistency. Probabilistic analysis ranked vernakalant and flecainide high and propafenone and amiodarone IV low.

CONCLUSION

For pharmacologic cardioversion of recent-onset AF within 24 h, there is insufficient evidence to determine which treatment is superior. Vernakalant and flecainide may be relatively more efficacious agents. Propafenone and IV amiodarone may be relatively less efficacious. Further high-quality study is necessary.

Explainable Artificial Intelligence Model for Diagnosis of Atrial Fibrillation Using Holter Electrocardiogram Waveforms

Atrial fibrillation is a clinically important arrhythmia. There are some reports on machine learning models for AF diagnosis using electrocardiogram data. However, few reports have proposed an eXplainable Artificial Intelligence (XAI) model to enable physicians to easily understand the machine learning model's diagnosis results.We developed and validated an XAI-enabled atrial fibrillation diagnosis model based on a convolutional neural network (CNN) algorithm. We used Holter electrocardiogram monitoring data and the gradient-weighted class activation mapping (Grad-CAM) method.Electrocardiogram data recorded from patients between January 4, 2016, and October 31, 2019, totaling 57,273 electrocardiogram waveform slots of 30 seconds each with diagnostic information annotated by cardiologists, were used for training our proposed model. Performance metrics of our AI model for AF diagnosis are as follows: sensitivity, 97.1% (95% CI: 0.969-0.972); specificity, 94.5% (95% CI: 0.943-0.946); accuracy, 95.3% (95% CI: 0.952-0.955); positive predictive value, 89.3% (95% CI: 0.892-0.897); and F-value, 93.1% (95% CI: 0.929-0.933). The area under the receiver operating characteristic curve for AF detection using our model was 0.988 (95% CI: 0.987-0.988). Furthermore, using the XAI method, 94.5 ± 3.5% of the areas identified as regions of interest using our machine learning model were identified as characteristic sites for AF diagnosis by cardiologists.AF was accurately diagnosed and favorably explained with Holter ECG waveforms using our proposed CNN-based XAI model. Our study presents another step toward realizing a viable XAI-based detection model for AF diagnoses for use by physicians.