Cost-effectiveness of population screening for atrial fibrillation: the STROKESTOP study.

AIMS: Previous studies on the cost-effectiveness of screening for atrial fibrillation (AF) are based on assumptions of long-term clinical effects. The STROKESTOP study, which randomised 27 975 persons aged 75/76 years into a screening invitation group and a control group, has a median follow-up time of 6.9 years. The aim of this study was to estimate the cost-effectiveness of population-based screening for AF using clinical outcomes. METHODS AND RESULTS: The analysis is based on a Markov cohort model. The prevalence of AF, the use of oral anticoagulation, clinical event data, and all-cause mortality were taken from the STROKESTOP study. The cost for clinical events, age-specific utilities, utility decrement due to stroke, and stroke death was taken from the literature. Uncertainty in the model was considered in a probabilistic sensitivity analysis. Per 1000 individuals invited to the screening, there were 77 gained life years and 65 gained quality-adjusted life years. The incremental cost was €1.77 million lower in the screening invitation group. Gained quality-adjusted life years to a lower cost means that the screening strategy was dominant. The result from 10 000 Monte Carlo simulations showed that the AF screening strategy was cost-effective in 99.2% and cost-saving in 92.7% of the simulations. In the base-case scenario, screening of 1000 individuals resulted in 10.6 [95% confidence interval (CI): -22.5 to 1.4] fewer strokes (8.4 ischaemic and 2.2 haemorrhagic strokes), 1.0 (95% CI: -1.9 to 4.1) more cases of systemic embolism, and 2.9 (95% CI: -18.2 to 13.1) fewer bleedings associated with hospitalization. CONCLUSION: Based on the STROKESTOP study, this analysis shows that a broad AF screening strategy in an elderly population is cost-effective. Efforts should be made to increase screening participation.

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.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants and warfarin in atrial fibrillation: a Scandinavian population-based cohort study.

AIMS: Using Scandinavian population-based registries, we assessed risk of stroke/systemic embolism (SE) and bleeding with non-vitamin K antagonist oral anticoagulants compared with warfarin in anticoagulation-naïve patients with atrial fibrillation (AF). METHODS AND RESULTS: This historical cohort study included 219 545 AF patients [median age 74 years; 43% women; mean CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischaemic attack, vascular disease, age 65-74 years, sex category) score 3.3] initiating apixaban, dabigatran, rivaroxaban, or warfarin in Denmark, Norway, and Sweden (1 January 2013 to 31 December 2016). The primary endpoints were stroke/SE and major bleeding. The median follow-up times were 9.7 (3.9-21.5) months for stroke/SE and 9.6 (3.8-21.3) months for bleeding. Apixaban and warfarin initiators were older and had higher CHA2DS2-VASc scores compared with dabigatran and rivaroxaban initiators. After 1:1 propensity score matching, three cohorts were created: apixaban-warfarin (n = 111 162), dabigatran-warfarin (n = 56 856), and rivaroxaban-warfarin (n = 61 198). Adjusted hazard ratios (HRs) were estimated using a Cox regression. For stroke/SE, adjusted HRs against warfarin were 0.96 [95% confidence interval (CI): 0.87-1.06] for apixaban, 0.89 (95% CI: 0.80-1.00) for dabigatran, and 1.03 (95% CI: 0.92-1.14) for rivaroxaban. For major bleeding, the HRs against warfarin were 0.73 (95% CI: 0.67-0.78) for apixaban, 0.89 (95% CI: 0.82-0.97) for dabigatran, and 1.15 (95% CI: 1.07-1.25) for rivaroxaban. The results in the dabigatran cohort did not hold in all dose-defined subgroups. CONCLUSION: In this large Scandinavian study among AF patients initiating oral anticoagulation, those initiating dabigatran, apixaban, and rivaroxaban had similar rates of stroke/SE to patients initiating warfarin. Rates of major bleeding were lower with apixaban and dabigatran and higher with rivaroxaban, each compared with warfarin.

Clinical outcomes in systematic screening for atrial fibrillation (STROKESTOP): a multicentre, parallel group, unmasked, randomised controlled trial.

BACKGROUND: Atrial fibrillation is a leading cause of ischaemic stroke. Early detection of atrial fibrillation can enable anticoagulant therapy to reduce ischaemic stroke and mortality. In this randomised study in an older population, we aimed to assess whether systematic screening for atrial fibrillation could reduce mortality and morbidity compared with no screening. METHODS: STROKESTOP was a multicentre, parallel group, unmasked, randomised controlled trial done in Halland and Stockholm in Sweden. All 75-76-year-olds residing in these two regions were randomly assigned (1:1) to be invited to screening for atrial fibrillation or to a control group. Participants attended local screening centres and those without a history of atrial fibrillation were asked to register intermittent electrocardiograms (ECGs) for 14 days. Treatment with oral anticoagulants was offered if atrial fibrillation was detected or untreated. All randomly assigned individuals were followed up in the intention-to-treat analysis for a minimum of 5 years for the primary combined endpoint of ischaemic or haemorrhagic stroke, systemic embolism, bleeding leading to hospitalisation, and all-cause death. This trial is registered with ClinicalTrials.gov, NCT01593553. FINDINGS: From March 1, 2012, to May 28, 2014, 28 768 individuals were assessed for eligibility and randomly assigned to be invited to screening (n=14 387) or the control group (n=14 381). 408 individuals were excluded from the intervention group and 385 were excluded from the control group due to death or migration before invitation. There was no loss to follow-up. Of those invited to screening, 7165 (51·3%) of 13 979 participated. After a median follow-up of 6·9 years (IQR 6·5-7·2), significantly fewer primary endpoint events occurred in the intervention group (4456 [31·9%] of 13 979; 5·45 events per 100 years [95% CI 5·52-5·61]) than in the control group (4616 [33·0%] of 13 996; 5·68 events per 100 years [5·52-5·85]; hazard ratio 0·96 [95% CI 0·92-1·00]; p=0·045). INTERPRETATION: Screening for atrial fibrillation showed a small net benefit compared with standard of care, indicating that screening is safe and beneficial in older populations. FUNDING: Stockholm County Council, the Swedish Heart & Lung Foundation, King Gustav V and Queen Victoria's Freemasons' Foundation, the Klebergska Foundation, the Tornspiran Foundation, the Scientific Council of Halland Region, the Southern Regional Healthcare Committee, the Swedish Stroke Fund, Carl Bennet AB, Boehringer Ingelheim, Bayer, and Bristol Myers Squibb-Pfizer.

Performance of pulse palpation compared to one-lead ECG in atrial fibrillation screening.

BACKGROUND: The 2020 European Society of Cardiology atrial fibrillation guidelines recommend opportunistic screening for atrial fibrillation by pulse taking or ECG rhythm strip in those aged over 65 years. HYPOTHESIS: We aimed to compare the diagnostic accuracy of pulse palpation to ECG rhythm strip when screening for atrial fibrillation. A secondary aim was to investigate whether participants with palpitations were more likely to be diagnosed with new atrial fibrillation. METHODS: The study population were 75/76 year old individuals that participated in the STROKESTOP II study, a Swedish screening study for atrial fibrillation. Pulse palpation of the radial pulse for 30 sec was performed by healthcare professionals and recorded as regular or irregular. Thereafter a 30-sec single-lead ECG was registered. Patients were asked also if they had a history of palpitations. RESULTS: Of the 6159 participants included in the study, 461 (7.5%) had irregular pulse. Twenty-two (4.8%) of those with irregular pulse were diagnosed with atrial fibrillation on single-lead ECG rhythm strip. Among those with regular pulse, 6 (0.1%) cases of new atrial fibrillation were found. The sensitivity of the pulse palpation test was 78.6% and positive predictive value 4.8%. The proportion of newly diagnosed atrial fibrillation was not different between those with and without history of palpitations. CONCLUSION: Pulse palpation was inferior to single-lead ECG when screening for atrial fibrillation. We therefore advocate the use of single-lead ECG rather than pulse palpation when screening for atrial fibrillation. Palpitations did not predict atrial fibrillation.

Decentralising atrial fibrillation screening to overcome socio-demographic inequalities in uptake in STROKESTOP II.

OBJECTIVE: In the first STROKESTOP atrial fibrillation screening study, participation was influenced by socio-demographic and geographic factors. To improve uptake in the second study, two screening sites were added, closer to low-income neighbourhoods which had very low participation in the first study. This paper aims to analyse the geographic and socio-demographic disparities in uptake in the second trial and compare the results with the first trial. METHODS: Inhabitants of the Stockholm region born in 1940 and 1941 were randomised 1:1 to be invited to screening or serve as controls. Medical history, blood samples and single-lead-ECG were collected. Invitee's residential parish was used for geo-mapping analysis of the geographical disparities in participation, using hierarchical Bayes methods. Individual data for participants and non-participants were obtained for the socioeconomic variables: educational level, disposable income, immigrant and marital status. RESULTS: Higher participation was observed in those with higher education, high income, among non-immigrants and married individuals. Participation between the first and second studies improved significantly, where additional screening sites were introduced. These improvements were generally significant, in each population group according to socio-demographic characteristics. CONCLUSION: Decentralisation of screening sites in an atrial fibrillation screening program yielded a significantly positive impact on screening uptake. Adding local screening sites in areas with low uptake had beneficial impact on participation across a wide spectrum of socio-demographic groups. Decentralised screening substantially increased the screening uptake in deprived areas.

Brief episodes of rapid irregular atrial activity (micro-AF) are a risk marker for atrial fibrillation: a prospective cohort study.

BACKGROUND: Short supraventricular tachycardias with atrial fibrillation (AF) characteristics are associated with an increased risk of developing AF over time. The aim of this study is to determine if presence of very short-lasting episodes of AF-like activity (micro-AF) can also be used as a marker of undiagnosed silent atrial fibrillation. METHODS: In the STROKESTOP II study, a Swedish mass screening study for AF among 75- and 76-year-olds, participants with NT-proBNP ≥125 ng/L performed intermittent ECG recordings 30 s, four times daily for 2 weeks. Participants with micro-AF (sudden onset of irregular tachycardia with episodes of ≥5 consecutive supraventricular beats and total absence of p-waves, lasting less than 30 s) were invited to undergo extended AF screening using continuous event recording for 2 weeks. A control group of individuals without micro-AF was examined using the same ECG modalities. RESULTS: Out of 3763 participants in STROKESTOP II who had elevated NT-proBNP levels and were free of AF, n = 221 (6%) had micro-AF. The majority of participants with micro-AF (n = 196) accepted further investigation with continuous ECG monitoring which showed presence of AF in 26 of them. In the control group (n = 250), continuous monitoring detected 7 new AF cases. Thus, AF was significantly more common in the micro AF group (13%) compared to the control group (3%), p < 0.001. CONCLUSIONS: Presence of short-lasting episodes of AF-like activity (micro-AF) indicates increased likelihood for undetected AF. Continuous screening therefore seems recommendable if a finding of AF would change clinical management. TRAIL REGISTRATION: ClinicalTrials.gov, identifier: NCT02743416, registered April 19, 2016.

Validity of daily self-pulse palpation for atrial fibrillation screening in patients 65 years and older: A cross-sectional study.

BACKGROUND: The European Society of Cardiology guidelines recommend (Class IA) single-time-point screening for atrial fibrillation (AF) using pulse palpation. The role of pulse palpation for AF detection has not been validated against electrocardiogram (ECG) recordings. We aimed to study the validity of AF screening using self-pulse palpation compared with an ECG recording conducted at the same time using a handheld ECG 3 times a day for 2 weeks. METHODS AND FINDINGS: In this cross-sectional screening study, patients 65 years of age and older attending 4 primary care centers (PCCs) outside Stockholm County were invited to take part in AF screening from July 2017 to December 2018. Patients were included irrespective of their reason for visiting the PCC. Handheld intermittent ECGs 3 times per day were offered to patients without AF for a period of 2 weeks, and patients were instructed in how to take their own pulse at the same time. A total of 1,010 patients (mean age 73 years, 61% female, with an average CHA2DS2-VASc score 2.9) participated in the study, and 27 (2.7%, 95% CI 1.8%-3.9%) new cases of AF were detected. Anticoagulants (ACs) could be initiated in 26 (96%, 95% CI 81%-100%) of these cases. A total of 53,782 simultaneous ECG recordings and pulse measurements were registered. AF was verified in 311 ECG recordings, of which the pulse was palpated as irregular in 77 recordings (25%, 95% CI 20%-30% sensitivity per measurement occasion). Of the 27 AF cases, 15 cases felt an irregular pulse on at least one occasion (56%, 95% CI 35%-75% sensitivity per individual). 187 individuals without AF felt an irregular pulse on at least one occasion. The specificity per measurement occasion and per individual was (98%, 95% CI 98%-98%) and (81%, 95% CI 78%-83%), respectively. CONCLUSIONS: AF screening using self-pulse palpation 3 times daily for 2 weeks has lower sensitivity compared with simultaneous intermittent ECG. Thus, it may be better to screen for AF using intermittent ECG without stepwise screening using pulse palpation. A limitation of this model could be the reduced availability of handheld ECG recorders in primary care centers.

Clinical and echocardiographic characteristics of individuals aged 75/76 years old with screening-detected elevated NT-proBNP levels.

Background: High plasma levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) indicate increased probability of congestive heart failure (CHF) and atrial fibrillation (AF) and are associated with poor prognosis. Objective: We aimed to describe the clinical and echocardiographic characteristics of a population of individuals aged 75/76 years old with NT-proBNP ≥900 ng/L without previously known CHF or AF. Methods: All individuals aged 75/76 years in the Stockholm region were randomised to a screening study for AF. Half of them were invited to screening. Of those invited, 49.5% agreed to participate. Individuals with NT-proBNP ≥900 ng/L without known CHF were invited for further clinical evaluation. Results: Among 6315 participants without AF who had NT-proBNP sampled, 102 without previously known CHF had ≥900 ng/L. Of these, 93 completed further clinical investigations. In the population that was clinically investigated, 53% were female, and the median NT-proBNP was 1200 ng/L. New AF was found in 28 (30%). The NT-proBNP value in this group was not significantly different from those where AF was not detected (median 1285 vs 1178 ng/L). Patients with newly detected AF had larger left atrial volume and higher pulmonary artery pressure than those without AF. Preserved left ventricular ejection fraction (≥50%) was found in 86% of the participants, mid-range ejection fraction (40%-49%) in 3.2% and reduced ejection fraction (<40%) in 10.8%. Thirteen patients (14%) had other serious cardiac disorders that required medical attention. Conclusion: Elderly individuals with NT-proBNP levels ≥900 ng/L constitute a population at high cardiovascular risk even in the absence of diagnosed CHF or AF, and therefore merit further investigation.

Effects of rivaroxaban and dabigatran on global hemostasis in patients with atrial fibrillation.

: The study was aimed to evaluate the effects of two standard doses of rivaroxaban and dabigatran on global hemostatic assays in patients with atrial fibrillation. The study included 52 patients treated with rivaroxaban (15/20 mg), 50 on dabigatran (110/150 mg) and 20 healthy individuals. Platelet-poor plasma was used for determination of three global hemostatic assays, namely endogenous thrombin potential (ETP), calibrated automated thrombogram (CAT) and overall hemostasis potential (OHP). Rivaroxaban and dabigatran reduced ETP (P < 0.01) although OHP (P < 0.05) was diminished only by dabigatran. Strong correlations were noticed between ETP parameters and the plasma concentrations of rivaroxaban (ETP, r = -0.51; c-max, r = -0.85; t-lag, r = 0.83; t-max, r = 0.66) as well as with plasma concentration of dabigatran (ETP, r = -0.75; c-max, r = -0.74; t-lag, r = 0.73; t-max, r = 0.52). Analysis of dabigatran concentrations under 50 ng/ml showed that ETP parameter has area under the concentration-time curve-receiver operating characteristic value of 0.879 (95% confidence interval 0.776-0.980). Dabigatran treatment paradoxically increased area under the concentration-time curve and peak values although rivaroxaban decreased peak values (P < 0.01). However, significant correlation between CAT parameters and plasma concentration of both direct oral anticoagulants was not observed. We confirmed that the CAT assay is inappropriate for estimation of dabigatran effects and is not fully sensitive as regards rivaroxaban. The ETP assay can potentially be the appropriate method for estimation of global hemostatic capacity as regards both direct oral anticoagulants. The role of OHP needs to be confirmed in additional studies. ETP parameter of chromogenic assay has promising potential in exclusion of high plasma concentrations of dabigatran.

Intermittent vs continuous electrocardiogram event recording for detection of atrial fibrillation-Compliance and ease of use in an ambulatory elderly population.

BACKGROUND: There are many atrial fibrillation (AF) screening devices available. Validation studies have mainly been performed in optimal settings in the young population. HYPOTHESIS: We aim to compare the yield of AF detection, compliance, and patient-based experience in an ambulatory elderly population by using intermittent electrocardiogram (ECG) recordings and continuous event recording simultaneously. METHODS: The study participants were part of the STROKESTOP II study, a Swedish screening study for AF. All participants were 75/76 years of age, were clinically free of AF, and had N-terminal pro b-type natriuretic peptides levels ≥125 ng/L. AF screening was performed in parallel during a 2-week period, using a continuous event recording device (R-test 4; Novacor) and 30-second intermittent recordings using a handheld ECG device (Zenicor II) four times daily. Participants were asked to fill out a questionnaire with regard to compliance and ease of use of the devices. RESULTS: During continuous event recording, 6% (n = 15/269) were diagnosed with AF and intermittent ECG detected AF in 2% (n = 5/269) of the participants (P = .002). No new cases of AF were detected using intermittent ECG monitoring only, but some episodes were detected in parallel for patients. On a graded ordinal scale of 1 to 5, with 1 reflecting "very easy to use", continuous monitoring was graded 2 (interquartile range [IQR]: 1-3) compared to intermittent 1 (IQR: 1-1) (P < .001). CONCLUSION: Continuous event recording detected three times more AF compared to intermittent ECG in an elderly ambulatory population. Compliance and user-friendliness were rated higher for the intermittent ECG device.

Stepwise mass screening for atrial fibrillation using N-terminal B-type natriuretic peptide: the STROKESTOP II study.

AIMS: To study the prevalence of unknown atrial fibrillation (AF) in a high-risk, 75/76-year-old, population using N-terminal B-type natriuretic peptide (NT-proBNP) and handheld electrocardiogram (ECG) recordings in a stepwise screening procedure. METHODS AND RESULTS: The STROKESTOP II study is a population-based cohort study in which all 75/76-year-old in the Stockholm region (n = 28 712) were randomized 1:1 to be invited to an AF screening programme or to serve as the control group. Participants without known AF had NT-proBNP analysed and were stratified into low-risk (NT-proBNP <125 ng/L) and high-risk (NT-proBNP ≥125 ng/L) groups. The high-risk group was offered extended ECG-screening, whereas the low-risk group performed only one single-lead ECG recording. In total, 6868 individuals accepted the screening invitation of which 6315 (91.9%) did not have previously known AF. New AF was detected in 2.6% [95% confidence interval (CI) 2.2-3.0] of all participants without previous AF. In the high-risk group (n = 3766/6315, 59.6%), AF was diagnosed in 4.4% (95% CI 3.7-5.1) of the participants. Out of these, 18% had AF on their index-ECG. In the low-risk group, one participant was diagnosed with AF on index-ECG. The screening procedure resulted in an increase in known prevalence from 8.1% to 10.5% among participants. Oral anticoagulant treatment was initiated in 94.5% of the participants with newly diagnosed AF. CONCLUSION: N-terminal B-type natriuretic peptide-stratified systematic screening for AF identified 4.4% of the high-risk participants with new AF. Oral anticoagulant treatment initiation was well accepted in the group diagnosed with new AF.

Assessment of N-terminal pro-B-type natriuretic peptide level in screening for atrial fibrillation in primary health care.

BACKGROUND: Atrial fibrillation (AF), an important cause of thromboembolic events, is often silent and intermittent, thus presenting a diagnostic challenge. The aim of this study was to assess whether the plasma level of N-terminal pro-brain natriuretic peptide (NT-proBNP) is related to the presence of AF and thereby might be used to facilitate screening programs for AF in primary care. METHODS: This was a cross sectional screening study. A population of 70-74-year-old individuals registered at a single primary care center in Stockholm were invited to AF screening. Intermittent ECG recording, 30 seconds twice a day using a hand-held device over 2 weeks, was offered to participants without previously known AF. Of the 324 participating persons, 34 patients had already known AF and 16 new cases of AF were detected by screening. Plasma NT-proBNP was measured in patients with previously known AF, newly detected AF, and 53 control participants without AF. FINDINGS: The median NT-proBNP was 697 ng/L in patients with previously known AF, 335 ng/L in new cases of AF, and 146 ng/L in patients without AF. After adjustment for several clinical variables and morbidities, the differences of median NT-proBNP levels were statistically significant between cases of previously known AF and new cases of AF as well as between new cases of AF and those without AF. The area under receiver operating characteristic curve of detection of new AF was 0.68 (95% CI 0.56 to 0.79) yielding a cut-off point of 124 ng/L with 75% sensitivity, 45% specificity, and 86% negative predictive value. CONCLUSIONS: The NT-proBNP plasma levels among patients with known AF are higher than those with newly detected AF, and the latter have higher levels than those without AF. Therefore NT-proBNP might be a useful screening marker for the detection of AF and its persistence.

Usefulness of Short-Lasting Episodes of Supraventricular Arrhythmia (Micro-Atrial Fibrillation) as a Risk Factor for Atrial Fibrillation.

According to the present European Society of Cardiology's guidelines for atrial fibrillation (AF), the definition of AF contains a 30-second time criterion, based on consensus. The aim of this cohort study is to evaluate whether very short-lasting episodes of AF, micro-AF, are risk factors for developing AF and to compare AF detection between continuous and intermittent ECG recordings applied in parallel. All participants, n = 102, were identified from the STROKESTOP study, a Swedish mass-screening study for AF. Participants were divided into 2 groups depending on results in the STROKESTOP study: a micro-AF group (with abrupt onset episodes of ≥4 consecutive supraventricular beats, irregular rate-to-rate intervals, absence of regular p waves, lasting for <30 seconds), n = 54, and a control group, n = 48. After a follow-up period participants who were clinically free of AF were invited to undergo repeat AF screening during a 2-week period, using continuous ECG recording and 30 seconds intermittent recordings simultaneously. After 2.3years of follow-up, significantly more participants in the micro-AF group had developed AF, 27 of 54 (50%), compared with the control group, 5 of 48 (10%), p < 0.001. Among the 94 participants not already diagnosed with AF who underwent AF-screening, 25 of 25 (100%) AF cases were detected with help of continuous monitoring whereas 10 of 25 (40%) AF cases were found with intermittent ECGs. In conclusion, micro-AF seems to be an important risk factor for the development of AF in an elderly population. The detection of AF was significantly higher using 2 weeks of continuous ECG monitoring compared with intermittent 30-second ECG recordings twice daily for 2 weeks.

Feasibility and outcomes of atrial fibrillation screening using intermittent electrocardiography in a primary healthcare setting: A cross-sectional study.

BACKGROUND: Atrial fibrillation (AF) is a major risk factor for ischemic stroke unless treated with an anticoagulant. Detecting AF can be difficult because AF is often paroxysmal and asymptomatic. The aims of this study were to develop a screening model to detect AF in a primary healthcare setting and to initiate oral anticoagulant therapy in high-risk patients to prevent stroke. METHODS: This was a cross-sectional study. All 70- to 74-year-old individuals registered at a single primary healthcare center in Stockholm were invited to participate in AF screening upon visiting the center during a ten-month period. Those who did not have contact with the center during this period were invited to participate by letter. Thirty-second intermittent ECG recordings were made twice a day using a handheld Zenicor device over a 2-week period in participants without AF. Oral anticoagulant therapy was offered to patients with newly detected AF. FINDINGS: Of the 415 eligible individuals, a total of 324 (78.1%) patients participated in the study. The mean age of the participants was 72 years, 52.2% were female, and the median CHA2DS2-VASc score of the participants was 3. In the target population, 34 (8.2%) individuals had previously diagnosed AF. Among participants without previously known AF, 16 (5.5%) cases of AF were detected. The final AF prevalence in the target population was 12%. Oral anticoagulant therapy was successfully initiated in 88% of these patients with newly detected AF. CONCLUSIONS: The AF screening project exhibited a high participation rate and resulted in a high rate of newly discovered AF; of these newly diagnosed patients, 88% could be treated with an oral anticoagulant.

Alcohol-related hospitalization is associated with increased risk of ischaemic stroke among low-risk patients with atrial fibrillation.

Aims: Patients with atrial fibrillation (AF) under the age of 65 and CHA2DS2-VASc risk score of 0 in men or 1 in women are considered to be at low risk for ischaemic stroke, and therefore without benefit of oral anticoagulation therapy. The objective of this study is to assess the incidence and predictors of ischaemic stroke among low-risk patients with AF identified from a National Patient Register. Methods and results: A retrospective study of 25 252 low-risk AF patients (age 18-64) out of total 345 123 AF patients identified from the Swedish Nationwide Patient Register for the period 1 January 2006 to 31 December 2012. During a median follow-up of 5.0 (interquartile range 2.9-6.8) years, ischaemic stroke occurred at an annual rate of 0.34 per 100 patient-years [95% confidence interval (CI) 0.31-0.38]. Significant predictors of stroke were age, hazard ratio (HR) 1.06 (CI 1.05-1.08) per incremental year, and previous alcohol-related hospitalization HR 2.01 (CI 1.45-2.79). Intracerebral bleeding events were rare and not statistically different HR 2.05 (CI 0.76-5.56) between patients with and without alcohol-related hospitalizations. Use of oral anticoagulants was associated with lower risk for ischaemic stroke, HR 0.78 (CI 0.63-0.97). Conclusion: The presence of a previous hospitalization with an alcohol-related disease was associated with a small but significant increase in the risk of stroke among low-risk AF patients. More research about relation between alcohol use and ischaemic stroke in AF patients is warranted.

[Incidence, investigation and long-term follow-up of macroscopic hematuria in patients treated with non vitamin K antagonist oral anticoagulant: Insight from a specialist cardiology clinic]. / Makroskopisk hematuri vid behandling med NOAK - Incidensen är låg ­ snar urologisk utredning krävs, visar retrospektiv studie vid hjärtspecialistmottagning.

Incidence, investigation and long-term follow-up of macroscopic hematuria in patients treated with non vitamin K antagonist oral anticoagulant: Insight from a specialist cardiology clinic In a retrospective long-term follow up of patients with non-valvular atrial fibrillation treated with non-vitamin K dependent oral anticoagulants in a specialist clinic, the incidence of reported macroscopic hematuria was relatively low and none of these was major bleeding. Urgent investigation of the bleeding source by a urologist showed different etiologies, like newly discovered neoplasm, benign hyperplasia of the prostate gland, renal stones, or inflammatory changes in the urinary bladder, and some had normal findings. The majority of patients continued oral anticoagulation therapy after investigation. Incidence of re-bleeding was very low.

N-terminal pro B-type natriuretic peptide in systematic screening for atrial fibrillation.

OBJECTIVE: Screening for atrial fibrillation (AF) in individuals aged 65 and above is recommended by the European Society of Cardiology. Increased levels of the biomarker N-terminal pro B-type natriuretic peptide (NT-proBNP) has in cohort studies been associated with incident AF.The aim of this study was to assess whether NT-proBNP could be useful for AF detection in systematic screening. METHODS: The Strokestop study entailed 7173 Swedish residents aged 75/76 that were screened for AF using twice daily intermittent ECG recordings during 2 weeks. In a substudy of 886 participants, the last 815 consecutive participants and 71 individuals with newly detected AF, levels of NT-proBNP were determined. RESULTS: Participants with newly detected AF (n=96) had a median NT-proBNP of 330 ng/L (IQR 121;634). In individuals without AF (n=742), median NT-proBNP was 171 ng/L (IQR 95;283), p<0.001. The CHA2DS2-VASc parameters did not differ significantly between individuals with newly detected AF and without AF nor between newly detected AF in the NT-proBNP cohort compared with the cohort where NT-proBNP was not assessed. Using an NT-proBNP cut-off of ≥125 ng/L in a non-acute setting yielded a negative predictive value of 92%, meaning that 35% fewer participants would need to be screened when applied to systematic AF screening. Adding weight to NT-proBNP further reduced participants needed to be screened with a preserved sensitivity. CONCLUSIONS: NT-proBNP was increased in individuals with newly detected AF. Prospective studies could clarify if NT-proBNP can be used to correctly select individuals that benefit most from AF screening. CLINICAL TRIALS: ClinicalTrials.gov. Identifier: NCT01593553.

Safe automatic one-lead electrocardiogram analysis in screening for atrial fibrillation.

AIMS: Screening for atrial fibrillation (AF) using intermittent electrocardiogram (ECG) recordings can identify individuals at risk of AF-related morbidity in particular stroke. We aimed to validate the performance of an AF screening algorithm compared with manual ECG analysis by specially trained nurses and physicians (gold standard) in 30 s intermittent one-lead ECG recordings. METHODS AND RESULTS: The STROKESTOP study is a mass-screening study for AF using intermittent ECG recordings. All individuals in the study without known AF registered a 30-s ECG recording in Lead I two times daily for 2 weeks, and all ECGs were manually interpreted. A computerized algorithm was used to analyse 80 149 ECG recordings in 3209 individuals. The computerized algorithm annotated 87.1% (n = 69 789) of the recordings as sinus rhythm/minor rhythm disturbances. The manual interpretation (gold standard) was that 69 758 ECGs were normal, making the negative predictive value of the algorithm 99.9%. The number of ECGs requiring manual interpretation in order to find one pathological ECG was reduced from 288 to 35. Atrial fibrillation was diagnosed in 84 patients by manual interpretation, in all of whom the algorithm indicated pathology. On an ECG level, 278 ECGs were manually interpreted as AF, and of these the algorithm annotated 272 ECGs as pathological (sensitivity 97.8%). CONCLUSION: Automatic ECG screening using a computerized algorithm safely identifies normal ECGs in Lead I and reduces the need for manual evaluation of individual ECGs with >85% with 100% sensitivity on an individual basis.

Designing an optimal screening program for unknown atrial fibrillation: a cost-effectiveness analysis.

AIMS: The primary objective of this study was to use computer simulations to suggest an optimal age for initiation of screening for unknown atrial fibrillation and to evaluate if repeated screening will add value. METHODS AND RESULTS: In the absence of relevant clinical studies, this analysis was based on a simulation model. More than two billion different designs of screening programs for unknown atrial fibrillation were simulated and analysed. Data from the published scientific literature and registries were used to construct the model and estimate lifelong effects and costs. Costs and effects generated by 2 147 483 648 different screening designs were calculated and compared. Program designs that implied worse clinical outcome and were less cost-effective compared to other programs were excluded from the analysis. Seven program designs were identified, and considered to be cost effective depending on what the health-care decision makers are ready to pay for gaining a quality-adjusted life-year (QALY). Screening at the age of 75 implied the lowest cost per gained QALY (€4 800/QALY). CONCLUSION: In conclusion, examining the results of more than two billion simulated screening program designs for unknown atrial fibrillation, seven designs were deemed cost-effective depending on how much we are prepared to pay for gaining QALYs. Our results showed that repeated screening for atrial fibrillation implied additional health benefits to a reasonable cost compared to one-off screening.