Arnljot Tveit

Background: Atrial fibrillation (AF) is a prevalent arrhythmia in endurance athletes, and many athletes report exercise as a trigger for AF episodes. We aimed to investigate the association between exercise sessions and arrhythmia episodes in endurance athletes with paroxysmal AF. Methods: In endurance athletes diagnosed with paroxysmal AF, we continuously monitored arrhythmia episodes using insertable cardiac monitors and report event rates per 24 hours and temporal relation of arrhythmias with exercise sessions. Sports watches and chest straps were used for exercise monitoring. Exercise with a heart rate of 76% to 84% and ≥ 85% of the individual maximum heart rate was classified as high and very high intensity, respectively. Results: Forty‐seven athletes (age 57±10, range 33–75 years, 3 women) were monitored with insertable cardiac monitors for a total of 55 994 hours (median 1008 [840–1344] equaling 42 days [35–56]) and performed a total of 1722 hours of exercise, of which 592 hours at high or very high intensity. Thirty‐one athletes (66%) had a total of 1445 (median 17 [3–33]) AF episodes during monitoring. Thirteen athletes (27%) had AF during exercise of whom 2 had AF during high‐intensity sessions. The event rate of AF was not higher during (0.34 per 24 hours [95% CI, 0.13–0.65]) or subsequently following an exercise session (0.37 [95% CI, 0.10–0.71]), compared with unrelated to exercise (>3 hours after, 0.61 [95% CI, 0.26–1.13]). There were no episodes of exercise‐related ventricular tachycardia. Conclusions: In this study on endurance athletes with paroxysmal AF, the rate of AF episodes was not increased during or subsequently following exercise sessions. Registration: URL: Study Details: NCT04991337. Effects of Detraining in Endurance Athletes With Atrial Fibrillation. ClinicalTrials.gov (NEXAF Detraining).

Background: The increasing prevalence of atrial fibrillation (AF), along with changes in cardiovascular risk factors, AF detection and oral anticoagulant use, may have altered the epidemiology of AF‐related stroke. However, population‐based data on long‐term trends remain limited. Methods: Using mandatory nationwide registry data from the Atrial Fibrillation in Norway (AFNOR) study (2001–2021), we identified incident stroke cases defined as first hospitalization or death due to stroke in individuals aged ≥15 years. Age‐standardized incidence rates were calculated using direct standardization. Sex‐ and age‐adjusted incidence rate ratios (IRR) were estimated using negative binomial regression. Results: Among 227 575 incident strokes, 66 795 (29.4%) were AF‐related, and increased from 22% to 31% during 2001–2021, with 69% of all AF‐related ischemic strokes occurring in non‐anticoagulated individuals. Incidence rate of AF‐related ischemic strokes remained stable overall (67.8 per 100 000 person‐years in 2001 to 68.4 in 2021; IRR=1.01; 95% CI, 1.00–1.03) but increased among individuals aged 15 to 64 years. Non‐AF ischemic strokes declined from 204.4 to 130.8 (IRR=0.98; 95% CI, 0.97–0.99). Incidence of AF‐related intracerebral hemorrhage in individuals aged ≥75 years increased, driven by anticoagulated patients. Incidence of non‐AF intracerebral hemorrhage decreased (IRR=0.98; 95% CI, 0.97–0.99). Conclusions: The favorable decline in ischemic stroke incidence from 2001 to 2021 did not include AF‐related strokes. AF‐related ischemic strokes increased in younger age groups, whereas AF‐related intracerebral hemorrhage increased in the oldest age groups driven by anticoagulated patients. These findings underscore the need for improved strategies for AF detection and stroke prevention, particularly in younger populations, and greater attention towards management of bleeding risk among older, anticoagulated individuals.

Aims: Stroke risk in atrial fibrillation (AF) patients increases over time, but the optimal reassessment interval remains unclear. This study evaluated changes in the CHA2DS2-VA score in AF patients with low (score 0) or intermediate (score 1) stroke risk and explored appropriate reassessment intervals. Methods and results: Using Norwegian national registries (2011–18), 40 782 individuals with incident AF aged ≥18 years and a low or intermediate CHA2DS2-VA score were identified. Patients were followed from first AF diagnosis until an increase in the CHA2DS2-VA score, and the proportion with increased score was assessed across age groups. The number needed to reassess to detect one new CHA2DS2-VA risk factor was calculated at different time intervals after AF diagnosis. The CHA2DS2-VA score increased in 50% of patients after a median follow-up of 1.7 years. The proportion of patients with an increased CHA2DS2-VA score was 19% at 6 months, 25% at 1 year, and 40% at 3 years after AF diagnosis. At 1 year, the proportion of patients with a new risk factor was lower in those aged 18–44 years (8%) and 45–54 years (14%) compared to those aged >55 years (30%), with the number needed to reassess at 1 year being 12, 7, and 3 patients, respectively. Conclusion: New risk factors emerged in half of AF patients within 1.7 years. Age-specific differences underscore the need for tailored reassessment, suggesting a shorter interval of 6 months for patients ≥55 years and 1 year for those <55 years and routinely at age 65 and 75 years.

Background and aim: Cardiac troponin T (cTnT) is a blood biomarker of myocardial injury that is associated with future adverse cardiovascular events in the general population. Left ventricular (LV) global longitudinal strain (GLS) and mechanical dispersion (MD) are metrics of systolic function and synchrony that can be obtained from cardiac imaging. Studies suggest an association between cTnT and echocardiographically assessed GLS and MD, but it is unknown whether cTnT relates to these metrics when assessed by cardiac magnetic resonance (CMR). We hypothesized that cTnT associates with GLS and with MD assessed by CMR feature tracking (CMR-FT) in the general population. Methods and results: cTnT and CMR-FT measurements were performed in 186 community dwellers from the Akershus Cardiac Examination 1950 Study. The participants’ age ranged from 68 to 70 years. Median cTnT concentration was 7.0 ng/L (interquartile interval 5.0–12.6 ng/L), median absolute value of GLS was 17.3% (interquartile interval 15.7–18.8%), and median MD was 80.7 milliseconds (interquartile interval 61.8–105.0 milliseconds). In multivariable linear regression models adjusted for common clinical risk factors of cardiovascular disease, with GLS and MD as outcome and cTnT as the predictor variable of interest, log10 transformed cTnT was significantly associated with both absolute GLS [β-coefficient −1.65, confidence interval (−2.84, −0.46)] and MD [β-coefficient 28.56, confidence interval (12.14, 44.92)]. Conclusion: In older adults from the general population, higher cTnT concentrations are associated with worse systolic function and synchrony assessed by CMR-FT LV GLS and MD, adding information about myocardial function to traditional risk factors.

Aims: Short-term treatment with calcium channel blockers lowers levels of N-terminal pro B-type natriuretic peptide (NT-proBNP) and reduces rhythm-related symptoms compared to treatment with beta-blockers. The aim of this study was to compare the effects of metoprolol and diltiazem for rate control in patients with permanent atrial fibrillation (AF) after 6 months. Methods and results: Men and women with permanent AF and preserved left ventricular systolic function were randomized to receive either diltiazem 360 mg or metoprolol 100 mg once daily. The primary endpoint was the level of NT-proBNP after a 6-month treatment period. Secondary endpoints included heart rate, rhythm-related symptoms and exercise capacity. A total of 93 patients (mean age 71 ± 7 years, 28 women) were randomized. After 6-months’ treatment, mean levels of NT-proBNP decreased in the diltiazem group and increased in the metoprolol group, with a significant between-group difference (409.8 pg/mL, 95% CI: 230.6–589.1, P < 0.001). Treatment with diltiazem significantly reduced rhythm-related symptoms compared to baseline, but no change was observed in the metoprolol group. Diltiazem and metoprolol had similar effects on heart rate and exercise capacity. Conclusion: Diltiazem reduced NT-proBNP levels and improved rhythm-related symptoms. Metoprolol increased peptide levels but had no impact on symptoms despite similar heart rate reduction. Non-dihydropyridine calcium channel blockers should be considered more often for rate control in permanent AF.

Background and Aims: The benefit of oral anticoagulant (OAC) therapy in atrial fibrillation (AF) and intermediate stroke risk is debated. In a nationwide Norwegian cohort with a non-sex CHA2DS2-VASc risk score of one, this study aimed to investigate (i) stroke and bleeding risk in AF patients with and without OAC treatment, and (ii) the risk of stroke in non-anticoagulated individuals with and without AF. Methods: A total of 1 118 762 individuals including 34 460 AF patients were followed during 2011–18 until ischaemic stroke, intracranial haemorrhage, increased CHA2DS2-VASc score, or study end. One-year incidence rates (IRs) were calculated as events per 100 person-years (%/py). Cox regression models provided adjusted hazard ratios (aHRs [95% confidence intervals]). Results: Among AF patients, the ischaemic stroke IR was 0.51%/py in OAC users and 1.05%/py in non-users (aHR 0.47 [0.37–0.59]). Intracranial haemorrhage IR was 0.28%/py in OAC users and 0.19%/py in non-users (aHR 1.23 [0.88–1.72]). Oral anticoagulant use was associated with an increased risk of major bleeding (aHR 1.37 [1.16–1.63]) but lower risk of the combined outcome of ischaemic stroke, major bleeding, and mortality (aHR 0.57 [0.51–0.63]). Non-anticoagulated individuals with AF had higher risk of ischaemic stroke compared to non-AF individuals with the same risk profile (aHR 2.47 [2.17–2.81]). Conclusions: In AF patients at intermediate risk of stroke, OAC use was associated with overall favourable clinical outcomes. Non-anticoagulated AF patients had higher risk of ischaemic stroke compared to the general population without AF with the same risk profile.

Background: We aimed to explore the predictive value of the carotid plaque score, compared with the Systematic Coronary Risk Evaluation 2 (SCORE2) risk prediction algorithm, on incident ischemic stroke and major adverse cardiovascular events and establish a prognostic cutoff of the carotid plaque score. Methods and Results: In the prospective ACE 1950 (Akershus Cardiac Examination 1950 study), carotid plaque score was calculated with ultrasonography at inclusion in 2012 to 2015. The largest plaque diameter in each extracranial segment of the carotid artery on both sides was scored from 0 to 3 points. The sum of points in all segments provided the carotid plaque score. The cohort was followed up by linkage to national registries for incident ischemic stroke and major adverse cardiovascular events (nonfatal ischemic stroke, nonfatal myocardial infarction, and cardiovascular death) throughout 2020. Carotid plaque score was available in 3650 (98.5%) participants, with mean±SD age of 63.9±0.64 years at inclusion. Only 462 (12.7%) participants were free of plaque, and and 970 (26.6%) had a carotid plaque score of >3. Carotid plaque score predicted ischemic stroke (hazard ratio [HR], 1.25 [95% CI, 1.15–1.36]) and major adverse cardiovascular events (HR, 1.21 [95% CI, 1.14–1.27]) after adjustment for SCORE2 and provided strong incremental prognostic information to SCORE2. The best cutoff value of carotid plaque score for ischemic stroke was >3, with positive predictive value of 2.5% and negative predictive value of 99.3%. Conclusions: The carotid plaque score is a strong predictor of ischemic stroke and major adverse cardiovascular events, and it provides incremental prognostic information to SCORE2 for risk prediction. A cutoff score of >3 seems to be suitable to discriminate high‐risk subjects. Registration Information: clinicaltrials.gov. Identifier: NCT01555411.

Background: Echocardiographic measures of left atrial volumes are powerful predictors of cardiovascular events and important for assessing diastolic dysfunction. Despite this, there is limited knowledge of factors influencing left atrial remodeling. In particular, the impact of blood pressure in those in their early 40s on left atrial volumes later in life has not been sufficiently elucidated. Methods and Results: We linked data from individuals born in 1950 who participated in the Age 40 Program, and the ACE (Akershus Cardiac Examination) 1950 Study. We divided the study population into quartiles of systolic blood pressure in their early 40s and assessed the proportion of individuals with an enlarged left atrium in their mid‐60s. The associations between blood pressure and left atrial volumes were assessed in linear regression analyses. Of the 2591 individuals included in this study, 1302 (50.3%) were women, and the mean age in the Age 40 Program was 40.1±0.3 years. Systolic blood pressure was 128.1±13.6 mm Hg and diastolic blood pressure was 78.3±9.5 mm Hg. Mean age in the ACE 1950 Study was 64.0±0.6 years. The proportion of individuals with an enlarged left atrium increased across the quartiles of systolic blood pressure ( P =0.001). Systolic blood pressure was independently associated with left atrial volumes; the end‐systolic volume was 0.09 mL (95% CI, 0.04–0.14 mL) larger per 1‐mm Hg higher systolic blood pressure. Conclusions: Our findings suggest that increased blood pressure in those in their early 40s is relevant for left atrial remodeling later in life. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01555411.

Aims: Mechanical dispersion measures left ventricular contraction heterogeneity and is associated with the risk of sudden cardiac death. However, the associations between mechanical dispersion and cardiovascular risk factors in early mid-life, and established biomarkers of sub-clinical myocardial injury and dysfunction are not known. We aimed to examine this in the general population.Methods and results: During 2012–15, we included 2527 Norwegian individuals from the general population born in 1950, with measurements of mechanical dispersion by 2D speckle tracking echocardiography and concentrations of high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) available. Mechanical dispersion was calculated as the standard deviation of the contraction duration of 17 strain segments. We assessed the associations between mechanical dispersion, concentrations of hs-cTnT and NT-proBNP, and cardiovascular risk factors collected at a national health screening survey two decades earlier. At echocardiography baseline, median age was 64 (interquartile range 63.5–64.5) years, 49.8% were women, 59.1% had hypertension, and 5.9% reported established coronary artery disease. Median mechanical dispersion was 38.0 (29.5–47.0) ms, median hs-cTnT concentration 6 (4–8) ng/L, and the median NT-proBNP concentration 54 (34–93) ng/L. Mechanical dispersion was associated with both hs-cTnT and NT-proBNP concentrations in multivariable models adjusted for clinical and echocardiographic variables. High body mass index, serum triglyceride concentrations, and low resting heart rate at Age 40 were independently associated with increased mechanical dispersion two decades later.Conclusion: Established risk factors at Age 40 are associated with mechanical dispersion two decades later, and mechanical dispersion is cross-sectionally associated with biomarkers of subclinical myocardial injury and dysfunction.