Atrial fibrillation incidence after coronary artery bypass graft surgery and percutaneous coronary intervention: the prospective AFAF cohort study

Objectives. Atrial fibrillation is a common arrhythmia in patients with ischemic heart disease. This study aimed to determine the cumulative incidence of new-onset atrial fibrillation after percutaneous coronary intervention or coronary artery bypass grafting surgery during 30 days of follow-up. Design. This was a prospective multi-center cohort study on atrial fibrillation incidence following percutaneous coronary intervention or coronary artery bypass grafting for stable angina or non-ST-elevation acute coronary syndrome. Heart rhythm was monitored for 30 days postoperatively by in-hospital telemetry and handheld thumb ECG recordings after discharge were performed. The primary endpoint was the cumulative incidence of atrial fibrillation 30 days after the index procedure. Results. In-hospital atrial fibrillation occurred in 60/123 (49%) coronary artery bypass graft and 0/123 percutaneous coronary intervention patients (p < .001). The cumulative incidence of atrial fibrillation after 30 days was 56% (69/123) of patients undergoing coronary artery bypass grafting and 2% (3/123) of patients undergoing percutaneous coronary intervention (p < .001). CABG was a strong predictor for atrial fibrillation compared to PCI (OR 80.2, 95% CI 18.1-354.9, p < .001). Thromboembolic stroke occurred in-hospital in one coronary artery bypass graft patient unrelated to atrial fibrillation, and at 30 days in two additional patients, one in each group. There was no mortality. Conclusion. New-onset atrial fibrillation during 30 days of follow-up was rare after percutaneous coronary intervention but common after coronary artery bypass grafting. A prolonged uninterrupted heart rhythm monitoring strategy identified additional patients in both groups with new-onset atrial fibrillation after discharge.

Haemodynamic changes after atrial fibrillation initiation in patients eligible for catheter ablation: a randomized controlled study

Aims

Atrial fibrillation (AF) haemodynamics is less well studied due to challenges explained by the nature of AF. Until now, no randomized data are available. This study evaluates haemodynamic variables after AF induction in a randomized setting.

Methods and results

Forty-two patients with AF who had been referred for ablation to the University Hospital, Linköping, Sweden, and had no arrhythmias during the 4-day screening period were randomized to AF induction vs. control (2:1). Atrial fibrillation was induced by burst pacing after baseline intracardiac pressure measurements. Pressure changes in the right and left atrium (RA and LA), right ventricle (RV), and systolic and diastolic blood pressures (SBP and DBP) were evaluated 30 min after AF induction compared with the control group. A total of 11 women and 31 men (median age 60) with similar baseline characteristics were included (intervention n = 27, control group n = 15). After 30 min in AF, the RV end-diastolic pressure (RVEDP) and RV systolic pressure (RVSP) significantly reduced compared with baseline and between randomization groups (RVEDP: P = 0.016; RVSP: P = 0.001). Atrial fibrillation induction increased DBP in the intervention group compared with the control group (P = 0.02), unlike reactions in SBP (P = 0.178). Right atrium and LA mean pressure (RAm and LAm) responses did not differ significantly between the groups (RAm: P = 0.307; LAm: P = 0.784).

Conclusion

Induced AF increased DBP and decreased RVEDP and RVSP. Our results allow us to understand some paroxysmal AF haemodynamics, which provides a haemodynamic rationale to support rhythm regulatory strategies to improve symptoms and outcomes.

Trial registration number clinicaltrialsgov

No NCT01553045. https://clinicaltrials.gov/ct2/show/NCT01553045?term=NCT01553045&rank=1.

Electrocardiogram Devices for Home Use: Technological and Clinical Scoping Review

BACKGROUND

Electrocardiograms (ECGs) are used by physicians to record, monitor, and diagnose the electrical activity of the heart. Recent technological advances have allowed ECG devices to move out of the clinic and into the home environment. There is a great variety of mobile ECG devices with the capabilities to be used in home environments.

OBJECTIVE

This scoping review aimed to provide a comprehensive overview of the current landscape of mobile ECG devices, including the technology used, intended clinical use, and available clinical evidence.

METHODS

We conducted a scoping review to identify studies concerning mobile ECG devices in the electronic database PubMed. Secondarily, an internet search was performed to identify other ECG devices available in the market. We summarized the devices' technical information and usability characteristics based on manufacturer data such as datasheets and user manuals. For each device, we searched for clinical evidence on the capabilities to record heart disorders by performing individual searches in PubMed and ClinicalTrials.gov, as well as the Food and Drug Administration (FDA) 510(k) Premarket Notification and De Novo databases.

RESULTS

From the PubMed database and internet search, we identified 58 ECG devices with available manufacturer information. Technical characteristics such as shape, number of electrodes, and signal processing influence the capabilities of the devices to record cardiac disorders. Of the 58 devices, only 26 (45%) had clinical evidence available regarding their ability to detect heart disorders such as rhythm disorders, more specifically atrial fibrillation.

CONCLUSIONS

ECG devices available in the market are mainly intended to be used for the detection of arrhythmias. No devices are intended to be used for the detection of other cardiac disorders. Technical and design characteristics influence the intended use of the devices and use environments. For mobile ECG devices to be intended to detect other cardiac disorders, challenges regarding signal processing and sensor characteristics should be solved to increase their detection capabilities. Devices recently released include the use of other sensors on ECG devices to increase their detection capabilities.

Atrial fibrillation: primary prevention, secondary prevention, and prevention of thromboembolic complications: part 1

Atrial fibrillation (AF), is the most common sustained cardiac arrhythmia. It was once thought to be benign as long as the ventricular rate was controlled, however, AF is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a MEDLINE search to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched via the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare noninvasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Cost-Effectiveness of Screening to Identify Patients With Atrial Fibrillation: A Systematic Review

BACKGROUND

Screening for Atrial Fibrillation (AF) is recommended for people aged above 65 years. Screening for AF in asymptomatic individuals can be beneficial by enabling earlier diagnosis and the commencement of interventions to reduce the risk of early events, thus improving patient outcomes. This study systematically reviews the literature about the cost-effectiveness of various screening methods for previously undiagnosed AF.

METHODS

Four databases were searched to identify articles that are cost-effectiveness studies conducted on screening for AF published from January 2000 to August 2022. The Consolidated Health Economic Evaluation Reporting Standards 2022 checklist was used to assess the quality of the selected studies. A previously published approach was used to assess the usefulness of each study for health policy makers.

RESULTS

The database search yielded 799 results, with 26 articles meeting the inclusion criteria. Articles were categorised into four subgroups: (i) population screening, (ii) opportunistic screening, (iii) targeted, and (iv) mixed methods of screening. Most of the studies screened adults ≥65 years of age. Most studies were performed from a 'health care payer perspective' and almost all studies used 'not screening' as a comparator. Almost all screening methods assessed were found to be cost-effective in comparison to 'not screening'. The reporting quality varied between 58% to 89%. The majority of the studies were found to be of limited usefulness for health policy makers, as none of the studies made any clear statements about policy change or implementation direction.

CONCLUSION

All approaches of AF screening were found to be cost-effective compared with no screening, while opportunistic screening was found to be the optimal approach in some studies. However, screening for AF in asymptomatic individuals is context specific and likely to be cost-effective depending on the population screened, screening approach, frequency, and the duration of screening.

14-day Holter monitoring for atrial fibrillation after ischemic stroke: The yield of guideline-recommended monitoring duration

Introduction:

Current European Stroke Organisation (ESO) guidelines recommend >48 h of continuous electrocardiographic monitoring for atrial fibrillation (AF) in all patients with ischemic stroke or transient ischemic attack (TIA) with undetermined origin. We assessed the yield of the guideline-recommended monitoring for AF, as well as of extending monitoring up to 14 days.

Patients and methods:

We included consecutive patients with stroke/TIA without AF in an academic hospital in The Netherlands. We reported AF incidence and number needed to screen (NNS) in the overall sample after 48 h and 14 days of Holter monitoring.

Results:

Among 379 patients with median age 63 years (IQR 55–73), 58% male, Holter monitoring detected 10 cases of incident AF during a median of 13 (IQR 12–14) days of monitoring. Seven AF cases were detected within the first 48 hours (incidence 1.85%, 95% CI 0.74–3.81; NNS 54), and three additional AF cases were recorded among the 362 patients with >48 h of monitoring and without AF ⩽ 48 h (incidence 0.83%, 95% CI: 0.17–2.42; NNS 121). All AF cases were detected within the first 7 days of monitoring. Our sample was subject to sampling bias favoring inclusion of participants with low AF risk.

Discussion:

Strengths of this work were the broad inclusion criteria as recommended by ESO guidelines, and high Holter adherence among participants. The analysis was limited by inclusion of lower-risk cases and a relatively small sample size.

Conclusion:

In low-risk patients with recent stroke or TIA, ESO guideline-recommended screening for AF resulted in a low AF yield, with limited additional value of monitoring up to 14 days. Our results underline the need for a personalized approach in determining a patient’s optimum duration for post-stroke non-invasive ambulatory monitoring.

Cost-effectiveness of screening for atrial fibrillation in a single primary care center at a 3-year follow-up

OBJECTIVES

The aim of this study was to estimate the cost-effectiveness of intermittent electrocardiogram (ECG) screening for atrial fibrillation (AF) among 70-74-year old individuals in primary care. We also aimed to assess adherence to anticoagulants, severe bleeding, stroke and mortality among screening-detected AF cases at three-year follow-up.

METHODS

A post hoc analysis based on a cross-sectional screening study for AF among 70-74-year old patients, who were registered at a single primary care center, was followed for three years for mortality. Data about adherence to anticoagulants, incidence of stroke and severe bleeding among screening-detected AF cases, were collected from patient's records. Markov model and Monte Carlo simulation were used to assess the cost-effectiveness of the screening program.

RESULTS

The mortality rate among screening-detected AF cases (n = 16) did not differ compared to the 274 individuals with no AF (hazard ratio 0.86, CI 0.12-6.44). Adherence to anticoagulants was 92%. There was no stroke or severe bleeding. The incremental cost-effectiveness ratio of screening versus no screening was EUR 2389/quality-adjusted life year (QALY) gained. The screening showed a 99% probability of being cost-effective compared to no screening at a willingness-to-pay threshold of EUR 20,000 per QALY.

CONCLUSION

Screening for AF among 70-74-year olds in primary care using intermittent ECG appears to be cost-effective at 3-year follow-up with high anticoagulants adherence and no increased mortality.

Cost-effectiveness of insertable cardiac monitors for diagnosis of atrial fibrillation in cryptogenic stroke in Australia

INTRODUCTION

Detection of atrial fibrillation (AF) is required to initiate oral anticoagulation (OAC) after cryptogenic stroke (CS). However, paroxysmal AF can be difficult to diagnose with short term cardiac monitoring. Taking an Australian payer perspective, we evaluated whether long-term continuous monitoring for 3 years with an insertable cardiac monitor (ICM) is cost-effective for preventing recurrent stroke in patients with CS.

METHODS

A lifetime Markov model was developed to simulate the follow-up of patients, comparing long-term continuous monitoring with an ICM to monitoring by conventional care. We used a linked evidence approach to estimate the rates of recurrent stroke when AF detection leads to initiation of OAC, as detected using ICM during the lifetime of the device or as detected using usual care. All diagnostic and patient management costs were modeled. Other model inputs were determined by literature review. Probabilistic sensitivity analysis (PSA) was undertaken to explore the effect of parameter uncertainty according to CHADS2 score and OAC treatment effect.

RESULTS

In the base-case analysis, the model predicted an incremental cost-effectiveness ratio (ICER) of A$29 570 per quality-adjusted life year (QALY). Among CHADS2 subgroups analyses, the ICER ranged from A$26 342/QALY (CHADS2 = 6) to A$42 967/QALY (CHADS2 = 2). PSA suggested that the probabilities of ICM strategy being cost-effective were 53.4% and 78.7%, at thresholds of $30 000 (highly cost-effective) and $50 000 per QALY (cost-effective), respectively.

CONCLUSIONS

Long-term continuous monitoring with an ICM is a cost-effective intervention to prevent recurrent stroke in patients following CS in the Australian context.

Detection of occult atrial fibrillation with 24-hour ECG after cryptogenic acute stroke or transient ischaemic attack: A retrospective cross-sectional study in a primary care database in Israel

Background

Ischaemic stroke or cerebrovascular accident (CVA) due to occult atrial fibrillation (AF) may cause severe morbidity and mortality. Diagnosing occult AF can be challenging and there is no consensus regarding the optimal duration of screening. A 24-hour Holter electrocardiogram (ECG) is frequently employed to detect occult AF following ischaemic CVA.

Objectives

Demonstration of occult AF detection rate using a 24-hour Holter ECG in a primary care setting with descriptive analyses of independent variables to compare AF detected and non-detected patients.

Methods

This retrospective cross-sectional study utilised primary care data and included patients 50 years and older with a new CVA or transient ischaemic attack (TIA) diagnosis followed by a 24-hour Holter examination within 6 months, between 01 January 2013 and 01 June 2019. The analyses included descriptive statistics comparing demographics and clinical characteristics in patients who had AF or Atrial Flutter (AFL) detection to those who did not.

Results

Out of 5015 eligible patients, 66 (1.3%) were diagnosed with AF/AFL, with a number needed to screen of 88.5. Compared with those without AF/AFL detection, those diagnosed were older (75.42 ± 7.89 vs. 69.89 ± 9.88, p = 0.050), had a higher prevalence of hypertension (80.3% vs. 66.8%, p = 0.021) and chronic kidney disease (CKD) (71.2% vs. 44.2%, p < 0.001).

Conclusion

24-hour Holter has a low AF/AFL detection rate. Older persons and those with hypertension or CKD are more likely to be detected with AF/AFL using this method.

2021 ISHNE/HRS/EHRA/APHRS Expert Collaborative Statement on mHealth in Arrhythmia Management: Digital Medical Tools for Heart Rhythm Professionals: From the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia-Pacific Heart Rhythm Society

Supplemental Digital Content is available in the text.

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia-Pacific Heart Rhythm Society describes the current status of mobile health technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self-management are novel aspects of mobile health. The promises of predictive analytics but also operational challenges in embedding mobile health into routine clinical care are explored.

2021 ISHNE/HRS/EHRA/APHRS Collaborative Statement on mHealth in Arrhythmia Management: Digital Medical Tools for Heart Rhythm Professionals

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia Pacific Heart Rhythm Society describes the current status of mobile health ("mHealth") technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self-management are novel aspects of mHealth. The promises of predictive analytics but also operational challenges in embedding mHealth into routine clinical care are explored.

2021 ISHNE/ HRS/ EHRA/ APHRS collaborative statement on mHealth in Arrhythmia Management: Digital Medical Tools for Heart Rhythm Professionals: From the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia Pacific Heart Rhythm Society

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology/ Heart Rhythm Society/ European Heart Rhythm Association/ Asia Pacific Heart Rhythm Society describes the current status of mobile health ("mHealth") technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self‐management are novel aspects of mHealth. The promises of predictive analytics but also operational challenges in embedding mHealth into routine clinical care are explored.

2021 ISHNE/HRS/EHRA/APHRS collaborative statement on mHealth in Arrhythmia Management: Digital Medical Tools for Heart Rhythm Professionals: From the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia Pacific Heart Rhythm Society

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology/Heart Rhythm Society/European Heart Rhythm Association/Asia Pacific Heart Rhythm Society describes the current status of mobile health (“mHealth”) technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self‐management are novel aspects of mHealth. The promises of predictive analytics but also operational challenges in embedding mHealth into routine clinical care are explored.

2021 ISHNE / HRS / EHRA / APHRS Collaborative Statement on mHealth in Arrhythmia Management: Digital Medical Tools for Heart Rhythm Professionals: From the International Society for Holter and Noninvasive Electrocardiology / Heart Rhythm Society / European Heart Rhythm Association / Asia Pacific Heart Rhythm Society

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology / Heart Rhythm Society / European Heart Rhythm Association / Asia Pacific Heart Rhythm Society describes the current status of mobile health ("mHealth") technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self-management are novel aspects of mHealth. The promises of predictive analytics but also operational challenges in embedding mHealth into routine clinical care are explored.

High Thrombin Generation after Acute Ischemic Stroke or Transient Ischemic Attack Is Associated with a Reduced Risk of Recurrence: An Observational Cohort Study

Thrombin is increasingly recognized to be of importance for cardiovascular disease. The aim of this study was to investigate the prognostic value of thrombin generation variables in a cohort of patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA). Thrombin generation potential measured by calibrated automated thrombogram (CAT) and prothrombin fragment F1 + 2 was determined in the acute and convalescent phases for a cohort of 190 patients with AIS/TIA. Microvesicle (MV)-induced thrombin generation potential was determined for a subset of patients using modified CAT. Primary outcome was a composite of fatal and nonfatal AIS or myocardial infarction as documented in Swedish registers during a total follow-up of 986 patient-years. Hazard ratios (HRs) were calculated using Cox regression based on variable median split. Peak thrombin and endogenous thrombin potential (ETP) above median in the acute phase were associated with a reduced risk of primary outcome after adjustment for cardiovascular risk factors, HR: 0.50 (0.27-0.92), p = 0.026 and HR: 0.53 (0.28-0.99), p = 0.048, respectively. F1 + 2 was lower in patients than in healthy controls but not associated with outcome. MV-induced peak thrombin above median in the acute phase was associated with recurrent AIS, unadjusted HR: 2.65 (1.03-6.44), p = 0.044. Contrary to expectation, high thrombin generation potential is associated with a reduced risk of recurrent ischemic event in patients with AIS/TIA. Low ETP/peak thrombin combined with high MV-induced peak thrombin can potentially identify patients at high risk of recurrence.

Patient-reported feasibility of chest and thumb ECG after cryptogenic stroke in Sweden: an observational study

OBJECTIVES

The aim of this study was to assess the feasibility, based on a questionnaire, of the chest and thumb ECG system Coala Heart Monitor in patients who recently had a stroke.

DESIGN

Observational study.

SETTING

Two stroke units, Region Gävleborg, Sweden.

PARTICIPANTS AND INTERVENTIONS

This study, Transient ECG Assessment in Stroke Evaluation (TEASE), included patients who had a stroke between 2017 and 2019. Patients eligible for anticoagulation in the presence of atrial fibrillation were scheduled for 28 days monitoring.

PRIMARY AND SECONDARY OUTCOME MEASURES

The questionnaire regarding feasibility of monitoring included seven questions, using a 100 mm Visual Analogue Scale which covered overall satisfaction, technical feasibility, remember to monitor, physical application, feeling of security, help from others and recommendation to others. A lower score indicated better outcome.

RESULTS

The prespecified number of 100 patients underwent the monitoring and 83 out of the 97 alive patients returned the questionnaire (response rate 85.6%). The median age was 69.5 years, mean CHA₂DS₂-VASc score was 4.4±1.3 points and 59.0% were men (n=49). The median time from index stroke to start of monitoring was 7.0 days. Patients performed on average 90.1%±15.0% of scheduled ECG-transmissions. In all seven questions, the median score ranged from 4 to 8. The vast majority reported acceptable outcomes, that is, the 95th percentile ranged from 30 to 54. There was no significant difference between men and women with regard to any of the seven questions (p values ranging from 0.117 to 0.849). Two of the seven outcome scores correlated significantly to patient age (Spearman's r=-0.238 and r=-0.308, and p values 0.031 and 0.005 for 'overall satisfaction' and 'remember to monitor', respectively).

CONCLUSION

In stroke survivors, chest and thumb ECG two times per day over a period of 4 weeks is feasible from a patient's perspective. The Coala Heart Monitor provides a valuable and convenient tool for monitoring after stroke.

TRIAL REGISTRATION NUMBER

NCT03301662.

Nurse Led Smartphone Electrographic Monitoring for Atrial Fibrillation after Ischemic Stroke: SPOT-AF

BACKGROUND AND PURPOSE

Paroxysmal atrial fibrillation (PAF) underlying acute stroke frequently evades detection by standard practice, considered to be a combination of routine electrocardiogram (ECG) monitoring, and 24-hour Holter recordings. We hypothesized that nurse-led in-hospital intermittent monitoring approach would increase PAF detection rate.

METHODS

We recruited patients hospitalised for stroke/transient ischemic attack, without history of atrial fibrillation (AF), in a prospective multi-centre observational study. Patients were monitored using a smartphone-enabled handheld ECG (iECG) during routine nursing observations, and underwent 24-hour Holter monitoring according to local practice. The primary outcome was comparison of AF detection by nurse-led iECG versus Holter monitoring in patients who received both tests: secondary outcome was oral anticoagulant commencement at 3-month following PAF detection.

RESULTS

One thousand and seventy-nine patients underwent iECG monitoring: 294 had iECG and Holter monitoring. AF was detected in 25/294 (8.5%) by iECG, and 8/294 (2.8%) by 24-hour Holter recordings (P<0.001). Median duration from stroke onset to AF detection for iECG was 3 days (interquartile range [IQR], 2 to 6) compared with 7 days (IQR, 6 to 10) for Holter recordings (P=0.02). Of 25 patients with AF detected by iECG, 11 were commenced on oral anticoagulant, compared to 5/8 for Holter. AF was detected in 8.8% (69/785 patients) who underwent iECG recordings only (P=0.8 vs. those who had both iECG and 24-hour Holter).

CONCLUSIONS

Nurse-led in-hospital iECG surveillance after stroke is feasible and effective and detects more PAF earlier and more frequently than routine 24-hour Holter recordings. Screening with iECG could be incorporated into routine post-stroke nursing observations to increase diagnosis of PAF, and facilitate institution of guideline-recommended anticoagulation.

Diagnostic yield of chest and thumb ECG after cryptogenic stroke, Transient ECG Assessment in Stroke Evaluation (TEASE): an observational trial

OBJECTIVE

In stroke survivors, atrial fibrillation (AF) is typically evaluated solely by short-term ECG monitoring in the stroke unit. Prolonged continuous ECG monitoring or insertable cardiac monitors require substantial resources. Chest and thumb ECG could provide an alternative means of AF detection, which in turn could allow prompt anticoagulation to prevent recurrent stroke. The objective of this study was to assess the yield of newly diagnosed AF during 28 days of chest and thumb ECG monitoring two times per day in cryptogenic stroke.

METHODS

This study, Transient ECG Assessment in Stroke Evaluation, included patients who had a stroke from Region Gävleborg, Sweden, between 2017 and 2019. Patients with a recent ischaemic stroke without documented AF (or other reasons for anticoagulation) before or during ECG evaluation in the stroke unit were evaluated using the Coala Heart Monitor connected to a smartphone application for remote monitoring.

RESULTS

The prespecified number of 100 patients (mean age 67.6±10.8 years; 60% men) was analysed. In nine patients (9%, number needed to screen 11) AF but no other significant atrial arrhythmias (>30 s) was diagnosed. The mean CHA₂DS₂-VASc score was similar among patients with AF and no AF (4.9±1.1 vs 4.3±1.3; p=0.224) and patients with AF were older (74.3±9.0 vs 66.9±10.8; p=0.049). Patients performed on average 90.1%±15.0% of scheduled transmissions.

CONCLUSION

In evaluation of cryptogenic stroke, 9% of patients had AF detected using chest and thumb ECG two times per day during 1 month. In many stroke survivors, this is a feasible approach and they will be potentially protected from recurrent stroke by anticoagulation treatment.

TRIAL REGISTRATION NUMBER

NCT03301662.

Screening of unknown atrial fibrillation through handheld device in the elderly

OBJECTIVE

To estimate the prevalence of unknown atrial fibrillation (AF) in the elderly population of the Veneto Region, Italy.

METHODS

1820 patients aged ≥ 65 years with no history of AF and not anticoagulated were enrolled in primary-care settings. They underwent an opportunistic electrocardiogram screening with a handheld device (MyDiagnostick) designed to specifically detect AF. The electrocardiogram recordings were reviewed by the researchers, who confirmed the presence of AF.

RESULTS

The device detected an arrhythmia in 143 patients, which was confirmed as AF in 101/143 (70.6%), with an overall prevalence of AF of 5.5% (101/1820). Prevalence of unknown AF resulted in 3.6% in patients aged 65-74 years, and 7.5% in patients age 75 or older, and increased according to CHA₂DS₂-VASc score: 3.5% in patients with a score of 1 or 2, 5.6% in patients with a score of 3, 7.0% in patients with a score of 4, and 7.2% in patients with a score ≥ 5. The detection rate was significantly higher in patients with mild symptoms compared to asymptomatic counterparts (24.1% vs. 4.0%, P < 0.0001). At multivariate analysis, congestive heart failure and age ≥ 75 years-old were independent predictors for screen-detected AF.

CONCLUSIONS

An opportunistic screening with handheld device revealed an unexpectedly high prevalence of unknown AF in elderly patients with mild symptoms. Prevalence increased with age and CHA₂DS₂-VASc score.

Emerging Technologies for Identifying Atrial Fibrillation

Atrial fibrillation (AF) is a major cause of morbidity and mortality globally, and much of this is driven by challenges in its timely diagnosis and treatment. Existing and emerging mobile technologies have been used to successfully identify AF in a variety of clinical and community settings, and while these technologies offer great promise for revolutionizing AF detection and screening, several major barriers may impede their effectiveness. The unclear clinical significance of device-detected AF, potential challenges in integrating patient-generated data into existing healthcare systems and clinical workflows, harm resulting from potential false positives, and identifying the appropriate scope of population-based screening efforts are all potential concerns that warrant further investigation. It is crucial for stakeholders such as healthcare providers, researchers, funding agencies, insurers, and engineers to actively work together in fulfilling the tremendous potential of mobile technologies to improve AF identification and management on a population level.

Identification of atrial fibrillation in secondary care diabetes and vascular clinics: a pilot study

Aim: To determine the feasibility and utility of the AliveCor® handheld ECG device in screening for asymptomatic atrial fibrillation in high-risk patients attending secondary care clinics. Materials & methods: Patients were recruited from diabetes and vascular outpatient clinics, and the AliveCor device used to store a 30-second ECG recording. Clinical risk stratification systems (CHAD2S2-VASc and HAS-BLED) assessed individual suitability for oral anticoagulation. Results: Atrial fibrillation was detected in 2 of 149 patients (1.3%), with CHA2DS2-VASc-derived annual stroke risk of 4%. Given low bleeding susceptibility (HAS-BLED), oral anticoagulation was strongly indicated. Conclusion: AliveCor technology offers a simple approach to retrieve large volumes of ECG data. A follow-up study with a larger cohort would reinforce the clinical utility of screening this high-risk population.

Screening for Atrial Fibrillation Using a Smartphone-Based Electrocardiogram in Korean Elderly

Atrial fibrillation (AF) is responsible for 10–20% of cerebral infarctions. Several mobile devices have been developed to screen for AF and studies of AF screening have been conducted in several countries to evaluate the applicability of these mobile devices. In this tradition, we conducted a community-based AF screening using an automated single-lead electrocardiogram (SL-ECG). This survey examined 2,422 participants in a community dementia screening program who were aged 60 years or older in the preliminary study, and 5,366 participants at 9 Senior Welfare Centers aged 60 years or older in the expanded study. AF screening was conducted using an automated SL-ECG (Kardia Mobile, AliveCor, Mountain View, CA, USA). AF was confirmed with a 12-lead electrocardiogram in subjects classified as having AF on the SL-ECG. In the preliminary study, of the 2,422 subjects, 124 had AF on the SL-ECG. The prevalence of AF was 3.0% (95% confidence interval [CI]: 2.4–3.8). The positive predictive value (PPV) of SL-ECG was 58.9% (95% CI: 50.1–67.1). Of the subjects diagnosed with AF, 65.8% (95% CI: 54.3–75.6) were newly diagnosed. In an expanded study, of the 5,366 subjects, 289 had AF on SL-ECG. The prevalence was 2.6% (95% CI: 2.2–3.1) and PPV of SL-ECG was 48.8% (95% CI: 43.1–54.5). In this community-based AF screening, we found that AF is underdiagnosed and undertreated. These results suggest that the early detection of AF using mobile devices is needed in Korea.

Prognostic Value of Circulating Microvesicle Subpopulations in Ischemic Stroke and TIA

Platelet microvesicles (PMV) have previously been found elevated in acute ischemic stroke (IS) and could be biomarkers for risk of recurrence. PMV surface antigens such as P-selectin and phosphatidylserine (PS) reflect platelet activation and procoagulance. Tissue factor-positive microvesicles (TF⁺MV) are considered procoagulant, in particular if co-expressing PS. We enumerated MV subpopulations with these surface antigens in a cohort of 211 patients with primarily non-cardioembolic IS or transient ischemic attack (TIA) and investigated their association with long-term outcome. MV concentrations were determined by flow cytometry in the acute and convalescent phase. Primary outcome was a composite of fatal and non-fatal recurrent IS or myocardial infarction. Secondary outcomes were recurrent IS and all-cause mortality. Outcome events were obtained from Swedish registers during a follow-up of 1100 patient years. Concentrations of PS-positive and PS-negative MV populations were elevated in patients compared with healthy controls in both the acute and convalescent phase. PS⁺TF⁺PMV displayed pronounced elevations, median fold change 77 in the acute phase (p < 0.0001) but were not associated with outcome, neither were PS⁺P-selectin⁺PMV. The only subpopulation positively associated with primary outcome was PS^-TF⁺PMV, with adjusted hazard ratio of 1.86 (1.04-3.31, p = 0.036) by Cox regression. Unexpectedly, several MV subpopulations tended to be associated with reduced risk of poor long-term outcome. Our results suggest that PS⁺TF⁺PMV may be a promising marker for cerebral ischemia, and that the in vivo generation of PS^-MV after IS/TIA warrants further study. Future MV studies should ideally enumerate PS⁺ and PS^-MV subpopulations separately.

Handheld ECG Tracking of in-hOspital Atrial Fibrillation The HECTO-AF trial Clinical Study Protocol

Background/rationale

Atrial fibrillation (AF) is frequent and causes great morbidity in the aging population. While initial events may be symptomatic, many patients have silent AF and are at risk of ischemic embolic complications. Timely detection of asymptomatic patients is paramount. The HECTO-AF trial aims to investigate the efficacy of an electrocardiogram (ECG) handheld device for the detection of AF in patients in hospital without a prior diagnosis of AF.

Methods/design

The “Handheld ECG tracking of in-hospital atrial fibrillation” (HECTO-AF) study is a single-center, open-label, randomized controlled trial. The study population consists of all adult patients admitted to a general medicine ward of the University and Hospital of Fribourg throughout the study period. The study will enroll 1600 patients with 1:1 ratio allocation to either the detection group with one-lead handheld ECG recordings twice daily and extra recordings in the case of palpitations, versus a control group undergoing detection of AF as per routine clinical practice. Recordings will be self-performed after dedicated training, and will be independently adjudicated through a specific web-based interface. All enrolled patients will be followed clinically at 1, 2 and 5 years to assess the occurrence of AF, death, non-fatal stroke, systemic embolism, myocardial infarction and bleeding. The primary outcome is incidence of newly detected AF during the hospital stay. Secondary outcomes are incidence of AF, cardiovascular death, stroke, myocardial infarction and bleeding complications at 1, 2 and 5 years.

Discussion

HECTO-AF is an independent randomized study aiming to detect the incidence of silent AF in all-comers hospitalized in general medicine wards.

Trial registration

ClinicalTrials.gov, NCT03197090. Registered on 23 June 2017. Local ethical Committee (CER-VD) registration number: 2017–01594. There are no conflicts of interest to declare.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3189-7) contains supplementary material, which is available to authorized users.

Newer technologies for detection of atrial fibrillation

Atrial fibrillation is a common arrhythmia that is associated with increased risk of stroke, which can be reduced with appropriate anticoagulation treatment. However, it remains underdiagnosed in contemporary clinical practice using conventional detection methods, resulting in missed opportunities to implement appropriate treatment. Newer technologies developed in recent years can potentially enhance the detection of atrial fibrillation and overcome certain limitations of the conventional methods. However, uncertainties remain about their use and the significance of atrial fibrillation detected by some of these newer technologies. This review examines the evidence supporting the use of some of these technologies and evaluates their applications in certain clinical scenarios.

Atrial fibrillation detection using single lead portable electrocardiographic monitoring: a systematic review and meta-analysis

OBJECTIVES

Recent technology advances have allowed for heart rhythm monitoring using single-lead ECG monitoring devices, which can be used for early diagnosis of atrial fibrillation (AF). We sought to investigate the AF detection rate using portable ECG devices compared with Holter monitoring.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

We searched the Medline, Embase and Scopus databases (conducted on 8 May 2017) using search terms related to AF screening and included studies with adults aged >18 years using portable ECG devices or Holter monitoring for AF detection. We excluded studies using implantable loop recorders and pacemakers. Using a random-effects model we calculated the overall AF detection rate. Meta-regression analysis was performed to explore potential sources for heterogeneity. Quality of reporting was assessed using the tool developed by Downs and Black.

RESULTS

Portable ECG monitoring was used in 18 studies (n=117 436) and Holter monitoring was used in 36 studies (n=8498). The AF detection rate using portable ECG monitoring was 1.7% (95% CI 1.4 to 2.1), with significant heterogeneity between studies (p<0.001). There was a moderate linear relationship between total monitoring time and AF detection rate (r=0.65, p=0.003), and meta-regression identified total monitoring time (p=0.005) and body mass index (p=0.01) as potential contributors to heterogeneity. The detection rate (4.8%, 95% CI 3.6% to 6.0%) in eight studies (n=10 199), which performed multiple ECG recordings was comparable to that with 24 hours Holter (4.6%, 95% CI 3.5% to 5.7%). Intermittent recordings for 19 min total produced similar AF detection to 24 hours Holter monitoring.

CONCLUSION

Portable ECG devices may offer an efficient screening option for AF compared with 24 hours Holter monitoring.

PROSPERO REGISTRATION NUMBER

CRD42017061021.

Holter Monitorisation Results in Early Period of Acute Ischemic Stroke

Introduction

Paroxysmal atrial fibrillation (PAF) has a similar risk with persistent AF for ischemic stroke. Holter monitorization (HM) and other long-term monitorization methods increased the detection of PAF and short-lasting runs of tachyarrhythmias. Their classification as PAF and roles in the etiology of ischemic stroke is controversial. In this study, we aimed to investigate the frequency of any duration of PAF and clinical characteristics of the patients with acute ischemic stroke who have undergone 24-hrs HM.

Methods

Patients with acute ischemic stroke and transient ischemic attack (TIA) hospitalized in the Neurology ward and undergone 24-hrs of HM during their hospital stay were included in the study. HM reports, clinical, and laboratory characteristics were analyzed, retrospectively. Patients were grouped into three based on HM: 1st group, without PAF; 2nd group, PAF >30 seconds (s) and 3rd group, PAF<30s.

Results

PAF of any duration was detected in 18.8% (n=49) of 261 patients. The duration of PAF was <30s in 16.1% (n=42) and >30s in 2.7% (n=7) of the patients. The mean age, left atrium diameter and CHA2DS2-VASc scores of the second group were significantly higher than the first group (p<0.001, p<0.001 and p=0.007; respectively). The mean age, left atrium diameter, modified Rankin Scores (mRS), and CHA2DS2-VASc scores of the third group were significantly higher than the first group (p<0.001; for all). There was no difference between the second and the third groups in means of mean age, left atrial diameter, MRS, and CHA2DS2-VASc scores (p<0.017, for all).

Conclusion

In this study, 24-hrs HM in the early period of acute ischemic stroke results yielded a high frequency of PAF<30s and predictive features were in parallel with the literature.

Atrial fibrillation is not uncommon among patients with ischemic stroke and transient ischemic stroke in China

Background

Atrial fibrillation (AF) is reported to be a less frequent cause of ischemic stroke in China than in Europe and North America, but it is not clear whether this is due to underestimation. Our aim was to define the true frequency of AF-associated stroke, to determine the yield of 6-day Holter ECG to detect AF in Chinese stroke patients, and to elucidate predictors of newly detected AF.

Methods

Patients with acute ischemic stroke or transient ischemic attack (TIA) were enrolled in a prospective, multicenter cohort study of 6-day Holter monitoring within 7 days after stroke onset at 20 sites in China between 2013 and 2015. Independent predictors of newly-detected AF were determined by multivariate analysis.

Results

Among 1511 patients with ischemic stroke and TIA (mean age 63 years, 33.1% women), 305 (20.2%) had either previously known (196, 13.0%) or AF newly-detected by electrocardiography (53, 3.5%) or by 6-day Holter monitoring (56/1262, 4.4%). A history of heart failure (OR = 4.70, 95%CI, 1.64–13.5), advanced age (OR = 1.06, 95%CI, 1.04–1.09), NIHSS at admission (OR = 1.06, 95%CI, 1.02–1.10), blood high density lipoprotein (HDL) (OR = 1.52, 95%CI, 1.09–2.13), together with blood triglycerides (OR = 0.64, 95%CI, 0.45–0.91) were independently associated with newly-detected AF.

Conclusions

Contrary to previous reports, AF-associated stroke is frequent (20%) in China if systemically sought. Prolonged noninvasive cardiac rhythm monitoring importantly increases AF detection in patients with recent ischemic stroke and TIA in China. Advanced age, history of heart failure, and higher admission NIHSS and higher level of HDL were independent indicators of newly-detected AF.

Trial registration

NCT02156765 (June 5, 2014).

Screening to identify unknown atrial fibrillation

Atrial fibrillation (AF) is associated with a significantly increased stroke risk which is highly preventable with appropriate oral anticoagulant therapy (OAC). However, AF may be asymptomatic and unrecognised prior to stroke. We aimed to determine if single time-point screening for AF could identify sufficient numbers with previously undiagnosed AF, to be effective for stroke prevention. This is a systematic review of clinical trials, by searching electronic medical databases, reference lists and grey literature. Studies were included if they evaluated a general ambulant adult population, using electrocardiography or pulse palpation to identify AF. We identified 30 individual studies (n=122,571, mean age 64 years, 54% male) in nine countries. Participants were recruited either from general practitioner and outpatient clinics (12 studies) or population screening/community advertisements (18 studies). Prevalence of AF across all studies was 2.3% (95% CI, 2.2–2.4%), increasing to 4.4% (CI, 4.1–4.6%) in those ≥65 years (16 studies, n= 27,884). Overall incidence of previously unknown AF (14 studies, n=67,772) was 1.0% (CI, 0.89–1.04%), increasing to 1.4% (CI, 1.2–1.6%) in those ≥65 years (8 studies, n= 18,189) in whom screening setting did not influence incidence identified. Of those with previously unknown AF, 67% were at high risk of stroke. Screening can identify 1.4% of the population ≥65 years with previously undiagnosed AF. Many of those identified would be eligible for, and benefit from OAC to prevent stroke. Given this incidence, community AF screening strategies in at risk older age groups could potentially reduce the overall health burden associated with AF.

Stepwise mass screening for atrial fibrillation using N-terminal pro b-type natriuretic peptide: the STROKESTOP II study design

Aim

Atrial fibrillation (AF) is the most prevalent clinical arrhythmia and a major risk factor for ischaemic stroke. Treatment with oral anticoagulants (OACs) reduces the risk of stroke by two thirds in AF patients with risk factors. Due to its often paroxysmal and asymptomatic presentation, AF is sometimes challenging to diagnose. So far, AF screening studies have applied opportunistic or systematic screening, most often using a single 12-lead electrocardiogram (ECG) recording or ambulatory ECG. We hypothesise that the biomarker N-terminal pro b-type natriuretic peptide (NT-proBNP) is a valuable adjunct in population based AF screening.

Methods

We are conducting a randomized population-based study on AF screening using ambulatory ECG recording where the decision to use prolonged intermittent ECG recording is directed by NT-proBNP levels, the STROKESTOP II trial. The entire population of inhabitants 75 or 76 years of age (n = 28 712) in the capital region of Sweden will be randomized 1:1 to intervention or control group. In the intervention group NT-proBNP will be analysed in all without previously known AF. Those with NT-proBNP ≤ 125 pg/L will make a single one lead ECG recording, participants with NTproBNP ≥ 125 np/L will be instructed to record ECG for 30 s at least twice daily for 2 weeks with a handheld ambulatory ECG recorder. Participants with newly diagnosed or undertreated AF will be referred to a cardiologist and offered OAC treatment. Primary endpoint is incidence of stroke or systemic embolus, during a 5 year follow-up period in the control group vs the group invited to screening.

Self-detection of atrial fibrillation in an aged population: three-year follow-up of the LietoAF intervention study

Background

Atrial fibrillation (AF) is often asymptomatic and undiagnosed until an ischaemic stroke occurs. An irregular pulse is a key manifestation of AF. We assessed whether pulse self-palpation is feasible in screening of AF.

Methods

Altogether 205 residents of Lieto municipality aged ≥75 years were randomized in 2012 to receive brief education on pulse palpation focusing on evaluating rhythm regularity. Self-detected pulse irregularity and new AF diagnoses were recorded, and the subjects’ quality of life and use of health care services were assessed during a three-year follow-up.

Results

The subjects’ median age was 78.2 [3.8] years, and 89 (43.4%) were men. Overall, 139 (68%) subjects had initial good motivation/capability for regular palpation. At four months, 112 (80.6%) subjects with good and 26 (39.4%) with inadequate motivation/capability palpated their pulse daily. At 12 months, 120 (58.5%) and at 36 months, 69 (33.7%) subjects palpated their pulse at least weekly. During the intervention, 67 (32.7%) subjects reported pulse irregularity. New AF was found in 10 (4.9%) subjects, 7 (70%) of whom had reported pulse irregularity. Pulse irregularity independently predicted new AF, but only one (0.5%) subject with new AF sought undelayed medical attention due to pulse irregularity. Quality of life and number of outpatient clinic visits remained unchanged during follow-up.

Conclusion

Pulse palpation can be learned also by the elderly, but it is challenging to form a continuing habit. The low persistence of pulse self-palpation limits its value in the screening of AF, and strategies to promote persistence and research on alternative screening methods are needed.

Trial registration

http://www.ClinicalTrials.gov identifier: NCT01721005. The trial was registered retrospectively on October 26, 2012.

Electronic supplementary material

The online version of this article (10.1186/s12877-017-0607-0) contains supplementary material, which is available to authorized users.

Screening strategies for atrial fibrillation: a systematic review and cost-effectiveness analysis

Background

Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of thromboembolic events. Anticoagulation therapy to prevent AF-related stroke has been shown to be cost-effective. A national screening programme for AF may prevent AF-related events, but would involve a substantial investment of NHS resources.

Objectives

To conduct a systematic review of the diagnostic test accuracy (DTA) of screening tests for AF, update a systematic review of comparative studies evaluating screening strategies for AF, develop an economic model to compare the cost-effectiveness of different screening strategies and review observational studies of AF screening to provide inputs to the model.

Design

Systematic review, meta-analysis and cost-effectiveness analysis.

Setting

Primary care.

Participants

Adults.

Intervention

Screening strategies, defined by screening test, age at initial and final screens, screening interval and format of screening {systematic opportunistic screening [individuals offered screening if they consult with their general practitioner (GP)] or systematic population screening (when all eligible individuals are invited to screening)}.

Main outcome measures

Sensitivity, specificity and diagnostic odds ratios; the odds ratio of detecting new AF cases compared with no screening; and the mean incremental net benefit compared with no screening.

Review methods

Two reviewers screened the search results, extracted data and assessed the risk of bias. A DTA meta-analysis was perfomed, and a decision tree and Markov model was used to evaluate the cost-effectiveness of the screening strategies.

Results

Diagnostic test accuracy depended on the screening test and how it was interpreted. In general, the screening tests identified in our review had high sensitivity (> 0.9). Systematic population and systematic opportunistic screening strategies were found to be similarly effective, with an estimated 170 individuals needed to be screened to detect one additional AF case compared with no screening. Systematic opportunistic screening was more likely to be cost-effective than systematic population screening, as long as the uptake of opportunistic screening observed in randomised controlled trials translates to practice. Modified blood pressure monitors, photoplethysmography or nurse pulse palpation were more likely to be cost-effective than other screening tests. A screening strategy with an initial screening age of 65 years and repeated screens every 5 years until age 80 years was likely to be cost-effective, provided that compliance with treatment does not decline with increasing age.

Conclusions

A national screening programme for AF is likely to represent a cost-effective use of resources. Systematic opportunistic screening is more likely to be cost-effective than systematic population screening. Nurse pulse palpation or modified blood pressure monitors would be appropriate screening tests, with confirmation by diagnostic 12-lead electrocardiography interpreted by a trained GP, with referral to a specialist in the case of an unclear diagnosis. Implementation strategies to operationalise uptake of systematic opportunistic screening in primary care should accompany any screening recommendations.

Limitations

Many inputs for the economic model relied on a single trial [the Screening for Atrial Fibrillation in the Elderly (SAFE) study] and DTA results were based on a few studies at high risk of bias/of low applicability.

Future work

Comparative studies measuring long-term outcomes of screening strategies and DTA studies for new, emerging technologies and to replicate the results for photoplethysmography and GP interpretation of 12-lead electrocardiography in a screening population.

Study registration

This study is registered as PROSPERO CRD42014013739.

Funding

The National Institute for Health Research Health Technology Assessment programme.

Atrial fibrillation trial to evaluate real-world procedures for their utility in helping to lower stroke events (AFTER-PULSE): Study protocol for a randomized controlled trial

Background

Enhancing detection of undiagnosed atrial fibrillation (AF) in hospitalized patients with a recent ischemic stroke is important because of the treatment implications; especially since presence of paroxysmal AF may not be picked up in a single 12-lead electrocardiogram (ECG) test. While several trials have shown improved detection of AF with prolonged ECG monitoring, this strategy is associated with relatively high cost, labor intensity, and patient inconvenience, thereby making it challenging to routinely implement in all hospitals. Fortunately, conventional 24-h Holter monitoring and repeated 12-lead ECGs are readily available to detect paroxysmal AF in all hospitals, but is unclear which is the better strategy for evaluating undiagnosed AF. The objective of his study is to conduct a randomized trial of serial 12-lead ECGs vs. 24-hour Holter monitoring in the detection of AF in ischemic stroke patients without known AF.

Methods and analysis

We plan to enroll 1200 participants from six hospitals in Taiwan. Patients will be eligible for enrollment if they are admitted for an acute ischemic stroke within 2 days, are ≥65 years of age, and have no known AF by history or on baseline ECG at admission. We will randomly assign participants in a 1:1 ratio to undergo daily 12-lead ECG once daily for 5 days (intervention group) or 24-h Holter monitoring (control group). Primary outcome is newly detected AF on a 12-lead ECG or AF lasting ≥30 s on Holter monitoring.

Trial registration number

ClinicalTrials.gov Identifier: NCT02578979.

Atrial high-rate episodes and stroke prevention

While the benefit of oral anticoagulants (OACs) for stroke prevention in patients with atrial fibrillation (AF) is well established, it is not known whether oral anticoagulation is indicated in patients with atrial high-rate episodes (AHRE) recorded on a cardiac implantable electronic device, sometimes also called subclinical AF, and lasting for at least 6 min in the absence of clinically diagnosed AF. Clinical evidence has shown that short episodes of rapid atrial tachycarrhythmias are often detected in patients presenting with stroke and transient ischaemic attack. Patients with AHRE have a higher likelihood of suffering from subsequent strokes, but their stroke rate seems lower than in patients with diagnosed AF, and not all AHRE episodes correspond to AF. The prognostic and pathological significance of AHRE is not yet fully understood. Clinical trials of OAC therapy are being conducted to determine whether therapeutic intervention would be beneficial to patients experiencing AHRE in terms of reducing the risk of stroke.

Neurohormonal Activation After Atrial Fibrillation Initiation in Patients Eligible for Catheter Ablation: A Randomized Controlled Study

BACKGROUND

Biomarker activation in atrial fibrillation (AF) has been widely studied, but the immediate effect of AF initiation remains unclear. We studied the effect of AF initiation on 2 cardiac biomarkers: the N-terminal fragment of the proB-type natriuretic peptide (NT-proBNP), the midregional fragment of the N-terminal of pro-atrial natriuretic peptide (MR-proANP), and 2 extracardiac biomarkers-the copeptin and the midregional portion of proadrenomedullin (MR-proADM).

METHODS AND RESULTS

This was a randomized controlled study, including 45 patients with AF who had been referred for radiofrequency ablation to the University Hospital, Linköping, Sweden, between February 2012 and April 2014. Freedom from AF during the 4 days prior to radiofrequency ablation was confirmed by transtelephonic ECGs. Biomarkers were collected from the femoral vein (fv), coronary sinus (CS), and left atrium (LA) prior to AF initiation (baseline) and 30 minutes later. The MR-proANP and NT-proBNP concentrations increased in the intervention group compared with the control group 30 minutes after the initiation of AF (MR-proANP: Pfv<0.001, PCS<0.001, PLA<0.001; NT-proBNP: PLA<0.001). Copeptin levels in patients without ischemic heart disease were decreased after the initiation of AF (Pfv=0.003, PCS=0.015, PLA=0.011).

CONCLUSIONS

AF is a strong stimulus that results in immediate activation of different biomarkers.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01553045.

Performance of short ECG recordings twice daily to detect paroxysmal atrial fibrillation in stroke and transient ischemic attack patients

Aims Prolonged cardiac monitoring after stroke is recommended though there is no consensus on optimal methods. Short-term ECG recordings with a "thumb-ECG" device have shown promising preliminary results regarding effectiveness and cost benefit. We aimed to examine the performance of thumb-ECG and five days' Holter monitoring in a prospective trial. A secondary endpoint was the inter-observer agreement of the thumb-ECG. Methods Patients older than 65 years with no history of atrial fibrillation who suffered an acute stroke or transient ischemic attack of unknown origin were prospectively included. Patients were monitored for atrial fibrillation with five days' Holter and concurrent 30 s thumb-ECG twice daily, the latter continuing for 30 days. Inter-observer agreement for the thumb-ECG was determined. Results One hundred patients were included and 95 patients were analyzed. Paroxysmal atrial fibrillation was diagnosed in 20 patients with the thumb-ECG recordings and 17 patients on the Holter monitoring. Only 10 were diagnosed with both methods. The difference between the detection rates of the two devices was not significant ( p = 0.63). The inter-observer agreement of the thumb-ECG had a kappa value of 0.65. Conclusion Thirty days' thumb-ECG recordings twice daily for 30 s detect a high proportion of paroxysmal atrial fibrillation in a stroke or transient ischemic attack cohort. The proportion was comparable to five days' Holter monitoring but the agreement between the two methods was poor and the trial was not powered to detect a minor difference between the devices. The inter-observer agreement for the thumb-ECG was substantial. www.clinicalTrials.gov UI: NCT02261766.

Detection of Atrial Fibrillation Among Patients With Stroke Due to Large or Small Vessel Disease: A Meta-Analysis

Background

Recent trials have demonstrated that extended cardiac monitoring increases the yield of paroxysmal atrial fibrillation (AF) detection in patients with cryptogenic stroke. The utility of extended cardiac monitoring is uncertain among patients with stroke caused by small and large vessel disease. We conducted a meta‐analysis to estimate the yield of AF detection in this population.

Methods and Results

We searched PubMed, Cochrane, and SCOPUS databases for studies on AF detection in stroke patients and excluded studies restricted to patients with cryptogenic stroke or transient ischemic attack. We abstracted AF detection rates for 3 populations grouped by stroke etiology: large vessel stroke, small vessel stroke, and stroke of undefined etiology (a mixture of cryptogenic, small vessel, large vessel, and other stroke etiologies). Our search yielded 30 studies (n=5687). AF detection rates were similar in patients with large vessel (2.2%, 95% CI 0.3–5.5; n=830) and small vessel stroke (2.4%, 95% CI 0.4–6.1; n=520). No studies had a monitoring duration longer than 7 days. The yield of AF detection in the undefined stroke population was higher (9.2%; 95% CI 7.1–11.5) compared to small vessel stroke (P=0.02) and large vessel stroke (P=0.02) populations.

Conclusions

AF detection rate is similar in patients with small and large vessel strokes (2.2–2.4%). Because no studies reported on extended monitoring (>7 days) in these stroke populations, we could not estimate the yield of AF detection with long‐term cardiac monitoring. Randomized controlled trials are needed to examine the utility of AF detection with long‐term cardiac monitoring (>7 days) in this patient population.

Detection of Atrial Fibrillation with Intermittent Handheld Electrocardiogram in Patients with Ischemic Stroke and Transient Ischemic Attack

BACKGROUND

Atrial fibrillation is an important risk factor for recurrent ischemic stroke and transient ischemic attack. Despite routine investigation, some patients' atrial fibrillation remains undetected. Intermittent handheld electrocardiogram (ECG) is an option for extended ECG monitoring aiming at enhancing detection rates. This study aimed to explore the detection rate of atrial fibrillation in stroke and transient ischemic attack patients with intermittent handheld ECG in the clinical setting of Halland Hospital Halmstad.

METHODS

Patients discharged with a diagnosis of ischemic stroke or transient ischemic attack who underwent intermittent handheld ECG recording at Halland Hospital Halmstad from January 1, 2010, to March 31, 2014, were retrospectively studied; 370 patients in total. A positive investigation was defined as either atrial fibrillation for a minimum of 10 seconds or a short irregular supraventricular run.

RESULTS

We found an overall atrial fibrillation detection rate of 7.6% (95% CI 5.1%-10.1%). The detection rate in stroke patients (11.0%) was significantly higher than in transient ischemic attack patients (5.0%), P = .032. The detection rate in patients aged less than 65 years was 4.2%, increasing to 9.8% in patients aged 65 years or older, P = .051.

CONCLUSION

This retrospective study shows an atrial fibrillation detection rate of 7.6% in a stroke and transient ischemic attack population using prolonged intermittent monitoring with handheld ECG recording. The compliance to the monitoring was excellent.

Echocardiographic measures of atrial function may predict atrial fibrillation in stroke patients

OBJECTIVE

In patients with a prior stroke or transient ischemic attack (TIA) and atrial fibrillation anticoagulant treatment is indicated. This study's purpose was to investigate if echocardiography can predict unknown AF in patients after stroke.

DESIGN

Prospectively, 174 stroke/TIA patients without diagnosed AF underwent echocardiographic evaluation including tissue Doppler imaging (TDI) focusing on functional parameters of the left atrium and left ventricular diastolic function. AF screening was performed during 30 d.

RESULTS

Fifteen patients (8.6%) were diagnosed with AF. Echocardiography in the AF group compared to those without AF, showed larger left atrial volume index (LAVI), (37.2 ± 6.7 vs. 31.6 ± 8.6 ml/m(2), p = 0.018), lower A' velocities in ventricular (5.9 ± 2.2 vs. 7.2 ± 1.6, p = 0.010) and atrial (4.8 ± 1.4 vs. 5.9 ± 1.4, p = 0.013) septa, higher LAVI/A' in ventricular septum (6.7 (5.0-8.7) vs. 4.2 (3.2-5.5), p = 0.001) and atrial septum (8.5 (5.9-11.0) vs. 5.1 (4.1-6.8), p = 0.003). Receiver operating characteristic analyses to detect AF was performed, area under the curve for LAVI was 0.71 (0.61-0.83), p = 0.008, and for LAVI/A' in ventricular septum 0.76 (0.59-0.93), p = 0.006 and atrial septum 0.78 (0.63-0.93), p = 0.002, respectively.

CONCLUSIONS

LAVI and measures of atrial contraction as measured by TDI predict unknown AF in patients after an stroke/TIA and may be used to detect silent AF.