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Recent neuroscience studies suggest that the hippocampus encodes a low-dimensional ordered representation of evidence through sequential neural activity. Cognitive modelers have proposed a mechanism by which such sequential activity could emerge through the modulation of the decay rate of neurons with exponentially decaying firing profiles. Through a linear transformation, this representation gives rise to neurons tuned to a specific magnitude of evidence, resembling neurons recorded in the hippocampus. Here we integrated this cognitive model inside reinforcement learning agents and trained the agents to perform an evidence accumulation task designed to mimic a task used in experiments on animals. We found that the agents were able to learn the task and exhibit sequential neural activity as a function of the amount of evidence, similar to the activity reported in the hippocampus.

AimsNo prior study has been adequately powered to evaluate real-world safety outcomes in those receiving adjunctive ablation lesions beyond pulmonary vein isolation (PVI). We sought to evaluate characteristics and in-hospital complications among patients undergoing PVI with and without adjunctive lesions.Methods and resultsPatients in the National Cardiovascular Data Registry AFib Ablation Registry undergoing first-time atrial fibrillation (AF) ablation between 2016 and 2020 were identified and stratified into paroxysmal (PAF) and persistent AF, and separated into PVI only, PVI + cavotricuspid isthmus (CTI) ablation, and PVI + adjunctive (superior vena cava isolation, coronary sinus, vein of Marshall, atypical atrial flutter lines, other). Adjusted odds of adverse events were calculated using multivariable logistic regression. A total of 50 937 patients [PAF: 30 551 (60%), persistent AF: 20 386 (40%)] were included. Among those with PAF, there were no differences in the adjusted odds of complications between PVI + CTI or PVI + adjunctive when compared with PVI only. Among persistent AF, PVI + adjunctive was associated with a higher risk of any complication [3.0 vs. 4.5%, odds ratio (OR) 1.30, 95% confidence interval (CI) 1.07-1.58] and major complication (0.8 vs. 1.4%, OR 1.56, 95% CI 1.10-2.21), while no differences were observed in PVI + CTI compared with PVI only. Overall, there was high heterogeneity in adjunctive lesion type, and those receiving adjunctive lesions had a higher comorbidity burden.ConclusionAdditional CTI ablation was common without an increased risk of complications. Adjunctive lesions other than CTI are commonly performed in those with more comorbidities and were associated with an increased risk of complications in persistent AF, although the current analysis is limited by high heterogeneity in adjunctive lesion set type.

IntroductionPersonal digital devices that provide health information, such as the Apple Watch, have developed an increasing array of cardiopulmonary tracking features which have received regulatory clearance and are directly marketed to consumers. Despite their widespread and increasing use, data about the impact of personal digital device use on patient-reported outcomes and healthcare utilisation are sparse. Among a population of patients with atrial fibrillation and/or atrial flutter undergoing cardioversion, our primary aim is to determine the impact of the heart rate measurement, irregular rhythm notification, and ECG features of the Apple Watch on quality of life and healthcare utilisation.Methods and analysisWe are conducting a prospective, open-label multicentre pragmatic randomised clinical trial, leveraging a unique patient-centred health data sharing platform for enrolment and follow-up. A total of 150 patients undergoing cardioversion for atrial fibrillation or atrial flutter will be randomised 1:1 to receive the Apple Watch Series 6 or Withings Move at the time of cardioversion. The primary outcome is the difference in the Atrial Fibrillation Effect on QualiTy-of-life global score at 6 months postcardioversion. Secondary outcomes include inpatient and outpatient healthcare utilisation. Additional secondary outcomes include a comparison of the Apple Watch ECG and pulse oximeter features with gold-standard data obtained in routine clinical care settings.Ethics and disseminationThe Institutional Review Boards at Yale University, Mayo Clinic, and Duke University Health System have approved the trial protocol. This trial will provide important data to policymakers, clinicians and patients about the impact of the heart rate, irregular rhythm notification, and ECG features of widely used personal digital devices on patient quality of life and healthcare utilisation. Findings will be disseminated to study participants, at professional society meetings and in peer-reviewed journals.Trial registration numberNCT04468321.

AimsTo determine the extent of shared decision-making (SDM), during selection of oral anticoagulant (OAC) and rhythm control treatments, in patients with newly diagnosed atrial fibrillation (AF).Methods and resultsWe evaluated survey data from 1006 patients with new-onset AF enrolled at 56 US sites participating in the SATELLITE substudy of the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT II). Patients completed surveys at enrolment and at 6-month follow-up. Patients were asked about who made their AF treatment decisions. Shared decision-making was classified as one that the patient felt was an autonomous decision or a shared decision with their healthcare provider (HCP). Approximately half of patients reported that their OAC treatment decisions were made entirely by their HCP. Compared with those reporting no SDM, patients reporting SDM for OAC were more often female (47.2% vs. 38.4%), while patients reporting SDM for rhythm control were more often male (62.2% vs. 57.6%). The most important factors cited by patients during decision-making for OAC were reducing stroke and bleeding risk, and their HCP's recommendations. After adjustment, patients with self-reported understanding of OAC, and rhythm control options, had higher odds of having participated in SDM [odds ratio (OR) 2.54, confidence interval (CI): 1.75-3.68 and OR 2.36, CI: 1.50-3.71, both P ≤ 0.001, respectively].ConclusionShared decision-making is not widely implemented in contemporary AF practice. Patient understanding about available therapeutic options is associated with a more than a two-fold higher likelihood of SDM, and may be a potential target for future interventions.

BackgroundAtrial fibrillation (AF) adversely impacts health-related quality of life (hrQoL). While some patients demonstrate improvements in hrQoL, the factors associated with large improvements in hrQoL are not well described.MethodsWe assessed factors associated with a 1-year increase in the Atrial Fibrillation Effect on Quality-of-Life score of 1 SD (≥18 points; 3× clinically important difference), among outpatients in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation I registry.ResultsOverall, 28% (181/636) of patients had such a hrQoL improvement. Compared with patients not showing large hrQoL improvement, they were of similar age (median 73 versus 74, P=0.3), equally likely to be female (44% versus 48%, P=0.3), but more likely to have newly diagnosed AF at baseline (18% versus 8%; P=0.0004), prior antiarrhythmic drug use (52% versus 40%, P=0.005), baseline antiarrhythmic drug use (34.8% versus 26.8%, P=0.045), and more likely to undergo AF-related procedures during follow-up (AF ablation: 6.6% versus 2.0%, P=0.003; cardioversion: 12.2% versus 5.9%, P=0.008). In multivariable analysis, a history of alcohol abuse (adjusted OR, 2.41; P=0.01) and increased baseline diastolic blood pressure (adjusted OR, 1.23 per 10-point increase and >65 mm Hg; P=0.04) were associated with large improvements in hrQoL at 1 year, whereas patients with prior stroke/transient ischemic attack, chronic obstructive pulmonary disease, and peripheral arterial disease were less likely to improve (P

BackgroundComorbidities are common in patients with atrial fibrillation (AF) and affect prognosis, yet are often undertreated. However, contemporary rates of use of guideline-directed therapies (GDT) for non-AF comorbidities and their association with outcomes are not well described.MethodsWe used the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF) to test the association between GDT for non-AF comorbidities and major adverse cardiac or neurovascular events (MACNE; cardiovascular death, myocardial infarction, stroke/thromboembolism, or new-onset heart failure), all-cause mortality, new-onset heart failure, and AF progression. Adjustment was performed using Cox proportional hazards models and logistic regression.ResultsOnly 6,782 (33%) of the 20,434 patients eligible for 1 or more GDT for non-AF comorbidities received all indicated therapies. Use of all comorbidity-specific GDT was highest for patients with hyperlipidemia (75.6%) and lowest for those with diabetes mellitus (43.1%). Use of "all eligible" GDT was associated with a nonsignificant trend toward lower rates of MACNE (HR 0.90 [0.79-1.02]) and all-cause mortality (HR 0.90 [0.80-1.01]). Use of GDT for heart failure was associated with a lower risk of all-cause mortality (HR 0.77 [0.67-0.89]), and treatment of obstructive sleep apnea was associated with a lower risk of AF progression (OR 0.75 [0.62-0.90]).ConclusionsIn AF patients, there is underuse of GDT for non-AF comorbidities. The association between GDT use and outcomes was strongest in heart failure and obstructive sleep apnea patients where use of GDT was associated with lower mortality and less AF progression.

Facebook groups and pages exist that expose the locations of roadside drug testing, potentially undermining police enforcement and enabling punishment avoidance. This study aimed to understand how and why these sites are used, with a focus on Queensland motorists who reported using illicit drugs and/or medical cannabis and used Facebook police location communities. Interviews with 30 participants were conducted. A thematic analysis revealed that participants used police location communities to avoid receiving a charge for driving under the influence of drugs. Upon observation of a relevant roadside drug-testing location on police location communities, participants reported (a) delaying their driving and/or (b) circumventing the operation. Avoidance of roadside drug-testing locations appeared driven by the perception that laws for driving under the influence of drugs were unfair and that a charge for driving under the influence of drugs would negatively impact their life. The findings provide important knowledge regarding police location communities and have implications for how roadside drug testing could be most effectively operated. [ABSTRACT FROM AUTHOR]

Background Chronic kidney disease ( CKD ) is a common comorbidity in patients with atrial fibrillation. The presence of CKD complicates drug selection for stroke prevention and rhythm control. Methods and Results Patients enrolled in ORBIT AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) with baseline renal function and follow-up data were included (N=9019). CKD was defined as an estimated creatinine clearance

Background Current American College of Cardiology/American Heart Association guidelines suggest that for patients with atrial fibrillation who are at low risk for stroke (CHA2DS2VASc=1) (or women with CHA2DS2VASc=2) a variety of treatment strategies may be considered. However, in clinical practice, patterns of treatment in these "low-risk" patients are not well described. The objective of this analysis is to define thromboembolic event rates and to describe treatment patterns in patients with low-risk CHA2DS2VASc scores. Methods and Results We compared characteristics, treatment strategies, and outcomes among patients with a CHA2DS2VASc=0, CHA2DS2VASc=1, females with a CHA2DS2VASc=2, and CHA2DS2VASc ≥2 in ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) I & II. Compared with CHA2DS2VASc ≥2 patients (84.2%), those with a CHA2DS2VASc=0 (60.3%), 1 (69.9%), and females with a CHA2DS2VASc score=2 (72.4%) were significantly less often treated with oral anticoagulation ( P

Background Current American College of Cardiology/American Heart Association guidelines suggest that for patients with atrial fibrillation who are at low risk for stroke (CHA2DS2VASc=1) (or women with CHA2DS2VASc=2) a variety of treatment strategies may be considered. However, in clinical practice, patterns of treatment in these "low-risk" patients are not well described. The objective of this analysis is to define thromboembolic event rates and to describe treatment patterns in patients with low-risk CHA2DS2VASc scores. Methods and Results We compared characteristics, treatment strategies, and outcomes among patients with a CHA2DS2VASc=0, CHA2DS2VASc=1, females with a CHA2DS2VASc=2, and CHA2DS2VASc ≥2 in ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) I & II. Compared with CHA2DS2VASc ≥2 patients (84.2%), those with a CHA2DS2VASc=0 (60.3%), 1 (69.9%), and females with a CHA2DS2VASc score=2 (72.4%) were significantly less often treated with oral anticoagulation ( P

ObjectiveTo describe self-reported disease understanding for newly diagnosed patients with atrial fibrillation (AF) and assess (1) how disease understanding changes over the first 6 months after diagnosis and (2) the relationship between patient understanding of therapies at baseline and treatment receipt at 6 months among treatment-naïve patients.MethodsWe analysed survey data from SATELLITE (Survey of Patient Knowledge and Personal Priorities for Treatment), a substudy of patients with new-onset AF enrolled in the national Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT) II registry across 56 US sites. Patients were surveyed at the baseline and 6-month follow-up clinic visits using Likert scales.ResultsAmong 1004 baseline survey responses, patients' confidence in their understanding of rhythm control, ablation, anticoagulation and cardioversion was suboptimal, with 'high' understanding ranging from 8.5% for left atrial appendage closure to 71.3% for rhythm therapy. Of medical history and demographic factors, education level was the strongest predictor of reporting 'high' disease understanding. Among the 786 patients with 6-month survey data, significant increases in the proportion reporting high understanding were observed (p

Non-vitamin K antagonist oral anticoagulants (NOACs) are indicated for stroke prevention in atrial fibrillation (AF) but require lower doses in certain patients. We sought to describe the frequency, appropriateness (according to Food and Drug Administration labeling), and outcomes of patients prescribed reduced doses of NOACs in community practice. We analyzed data from the ORBIT-AF II (The Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II) registry, a prospective, national, observational registry of AF patients. Among 7925 AF patients receiving NOACs, we assessed patterns of use of reduced NOAC doses and associated cardiovascular and bleeding outcomes at median follow-up of 1 year. Overall, 6636 patients (84%) received a NOAC at standard dose, which was consistent with US Food and Drug Administration labeling in 6376 (96%). Reduced NOAC dose was prescribed to 1289 (16% overall), which was consistent with Food and Drug Administration labeling in only 555 patients (43%). Compared with those whose NOAC dose was appropriately reduced, patients receiving inappropriate dose reductions were younger (median age 79 versus 84, P

BackgroundOral anticoagulation (OAC) therapy is associated with increased periprocedural risks after cardiac implantable electronic device (CIED) implantation. Patterns of anticoagulation management involving non-vitamin K antagonist oral anticoagulants (NOACs) have not been characterized.HypothesisAnticoagulation strategies and outcomes differ by anticoagulant type in patients undergoing CIED implantation.MethodsUsing the nationwide Outcomes Registry for Better Informed Treatment of Atrial Fibrillation, we assessed how atrial fibrillation (AF) patients undergoing CIED implantation were cared for and their subsequent outcomes. Outcomes were compared by oral anticoagulant therapy (none, warfarin, or NOAC) as well as by anticoagulation interruption status.ResultsAmong 9129 AF patients, 416 (5%) underwent CIED implantation during a median follow-up of 30 months (interquartile range, 24-36). Of these, 60 (14%) had implantation on a NOAC. Relative to warfarin therapy, those on a NOAC were younger (70.5 years [range, 65-77.5 years] vs 77 years [range, 70-82 years]), had less valvular heart disease (15.0% vs 31.3%), higher creatinine clearance (67.3 [range, 59.7-99.0] vs 65.8 [range, 50.0-91.6]), were more likely to have persistent AF (26.7% vs 22.9%), and use concomitant aspirin (51.7% vs 35.2%). OAC therapy was commonly interrupted for CIED in 64% (n = 183 of 284) of warfarin patients and 65% (n = 39 of 60) of NOAC patients. Many interrupted patients received intravenous bridging anticoagulation: 33/183 (18%) interrupted warfarin and 4/39 (10%) interrupted NOAC patients. Thirty-day periprocedure bleeding and stroke adverse events were infrequent.ConclusionsManagement of anticoagulation among AF patients undergoing CIED implantation is highly variable, with OAC being interrupted in more than half of both warfarin- and NOAC-treated patients. Bleeding and stroke events were infrequent in both warfarin and NOAC-treated patients.

BackgroundPatients with sinus node dysfunction (SND) have increased risk of atrial tachyarrhythmias, including atrial fibrillation (AF). To date, treatment patterns and outcomes of patients with SND and AF have not been well described.HypothesisPatients with SND and AF have higher risk of adverse cardiovascular outcomes.MethodsSinus node dysfunction was defined clinically, based on treating physician. Treatment patterns were described and logistic regression analysis performed to assess outcomes.ResultsOverall, 1710 (17.7%) out of 9631 patients had SND at enrollment. Patients with SND and AF had increased comorbid medical illnesses, more severe symptoms (European Heart Rhythm Association class IV: 17.5% vs 13.9%; P = 0.0007), and poorer quality of life (median 12-month Atrial Fibrillation Effect on Quality of Life score: 79.6 vs 85.2; P = 0.0008). There were no differences in AF management strategy between patients with SND and those without (rate control, 69.7% vs 67.7%; rhythm control, 30.0% vs 32.0%; P = 0.11). After adjustment, patients with SND were more likely than those without SND to progress from paroxysmal AF at baseline to persistent or permanent AF at any follow-up, or persistent AF at baseline to permanent AF at any follow-up (odds ratio: 1.23, 95% confidence interval: 1.01-1.49, P = 0.035). However, there was no association between SND and major risk-adjusted outcomes.ConclusionsSinus node dysfunction is present in 1 of 6 patients with AF and is associated with increased comorbidities and higher symptom burden. However, SND is not associated with an increase in major risk-adjusted outcomes.

ObjectiveAtrial fibrillation (AF) often progresses from paroxysmal or persistent to more sustained forms, but the rate and predictors of AF progression in clinical practice are not well described.MethodsUsing the Outcomes Registry for Better Informed Treatment of AF, we analysed the incidence and predictors of progression and tested the discrimination and calibration of the HATCH (hypertension, age, TIA/stroke, chronic obstructive pulmonary disease, heart failure) and CHA₂DS₂VASc scores for identifying AF progression.ResultsAmong 6235 patients with paroxysmal or persistent AF at baseline, 1479 progressed, during follow-up (median 18 (IQR 12-24) months). These patients were older and had more comorbidities than patients who did not progress (CHADS₂ 2.3±1.3 vs 2.1±1.3, p

BackgroundDigoxin remains commonly used for rate control in atrial fibrillation, but limited data exist supporting this practice and some studies have shown an association with adverse outcomes. We examined the independent association between digoxin and risks of death and hospitalization in adults with incident atrial fibrillation and no heart failure.Methods and resultsWe performed a retrospective cohort study of 14,787 age, sex, and high-dimensional propensity score-matched adults with incident atrial fibrillation and no previous heart failure or digoxin use in the AnTicoagulation and Risk factors In Atrial fibrillation-Cardiovascular Research Network (ATRIA-CVRN) study within Kaiser Permanente Northern and Southern California. We examined the independent association between newly initiated digoxin and the risks of death and hospitalization using extended Cox regression. During a median 1.17 (interquartile range, 0.49-1.97) years of follow-up among matched patients with atrial fibrillation, incident digoxin use was associated with higher rates of death (8.3 versus 4.9 per 100 person-years; P