Prior History Of Atrial Fibrillation Research Articles

Mavacamten Treatment for Symptomatic Obstructive Hypertrophic Cardiomyopathy: Interim Results From the MAVA-LTE Study, EXPLORER-LTE Cohort

BackgroundData assessing the long-term safety and efficacy of mavacamten treatment for symptomatic obstructive hypertrophic cardiomyopathy are needed. ObjectivesThe authors sought to evaluate interim results from the EXPLORER-Long Term Extension (LTE) cohort of MAVA-LTE (A Long-Term Safety Extension Study of Mavacamten in Adults Who Have Completed EXPLORER-HCM; NCT03723655). MethodsAfter mavacamten or placebo withdrawal at the end of the parent EXPLORER-HCM (Clinical Study to Evaluate Mavacamten [MYK-461] in Adults With Symptomatic Obstructive Hypertrophic Cardiomyopathy; NCT03470545), patients could enroll in MAVA-LTE. Patients received mavacamten 5 mg once daily; adjustments were made based on site-read echocardiograms. ResultsBetween April 9, 2019, and March 5, 2021, 231 of 244 eligible patients (94.7%) enrolled in MAVA-LTE (mean age: 60 years; 39% female). At data cutoff (August 31, 2021) 217 (93.9%) remained on treatment (median time in study: 62.3 weeks; range: 0.3-123.9 weeks). At 48 weeks, patients showed improvements in left ventricular outflow tract (LVOT) gradients (mean change ± SD from baseline: resting: −35.6 ± 32.6 mm Hg; Valsalva: −45.3 ± 35.9 mm Hg), N-terminal pro–B-type natriuretic peptide (NT-proBNP) levels (median: −480 ng/L; Q1-Q3: −1,104 to −179 ng/L), and NYHA functional class (67.5% improved by ≥1 class). LVOT gradients and NT-proBNP reductions were sustained through 84 weeks in patients who reached this timepoint. Over 315 patient-years of exposure, 8 patients experienced an adverse event of cardiac failure, and 21 patients had an adverse event of atrial fibrillation, including 11 with no prior history of atrial fibrillation. Twelve patients (5.2%) developed transient reductions in site-read echocardiogram left ventricular ejection fraction of <50%, resulting in temporary treatment interruption; all recovered. Ten patients discontinued treatment due to treatment-emergent adverse events. ConclusionsMavacamten treatment showed clinically important and durable improvements in LVOT gradients, NT-proBNP levels, and NYHA functional class, consistent with EXPLORER-HCM. Mavacamten treatment was well tolerated over a median 62-week follow-up.

Arrhythmic Risk in Biventricular Pacing Compared With Left Bundle Branch Area Pacing: Results From the I-CLAS Study.

Left bundle branch area pacing (LBBAP) may be associated with greater improvement in left ventricular ejection fraction and reduction in death or heart failure hospitalization compared with biventricular pacing (BVP) in patients requiring cardiac resynchronization therapy. We sought to compare the occurrence of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) and new-onset atrial fibrillation (AF) in patients undergoing BVP and LBBAP. The I-CLAS study (International Collaborative LBBAP Study) included patients with left ventricular ejection fraction ≤35% who underwent BVP or LBBAP for cardiac resynchronization therapy between January 2018 and June 2022 at 15 centers. We performed propensity score-matched analysis of LBBAP and BVP in a 1:1 ratio. We assessed the incidence of VT/VF and new-onset AF among patients with no history of AF. Time to sustained VT/VF and time to new-onset AF was analyzed using the Cox proportional hazards survival model. Among 1778 patients undergoing cardiac resynchronization therapy (BVP, 981; LBBAP, 797), there were 1414 propensity score-matched patients (propensity score-matched BVP, 707; propensity score-matched LBBAP, 707). The occurrence of VT/VF was significantly lower with LBBAP compared with BVP (4.2% versus 9.3%; hazard ratio, 0.46 [95% CI, 0.29-0.74]; P<0.001). The incidence of VT storm (>3 episodes in 24 hours) was also significantly lower with LBBAP compared with BVP (0.8% versus 2.5%; P=0.013). Among 299 patients with cardiac resynchronization therapy pacemakers (BVP, 111; LBBAP, 188), VT/VF occurred in 8 patients in the BVP group versus none in the LBBAP group (7.2% versus 0%; P<0.001). In 1194 patients with no history of VT/VF or antiarrhythmic therapy (BVP, 591; LBBAP, 603), the occurrence of VT/VF was significantly lower with LBBAP than with BVP (3.2% versus 7.3%; hazard ratio, 0.46 [95% CI, 0.26-0.81]; P=0.007). Among patients with no history of AF (n=890), the occurrence of new-onset AF >30 s was significantly lower with LBBAP than with BVP (2.8% versus 6.6%; hazard ratio, 0.34 [95% CI, 0.16-0.73]; P=0.008). The incidence of AF lasting >24 hours was also significantly lower with LBBAP than with BVP (0.7% versus 2.9%; P=0.015). LBBAP was associated with a lower incidence of sustained VT/VF and new-onset AF compared with BVP. This difference remained significant after adjustment for differences in baseline characteristics between patients with BVP and LBBAP. Physiological resynchronization by LBBAP may be associated with lower risk of arrhythmias compared with BVP.

Incidentally induced atrial fibrillation during programmed electrical stimulation in patients with depressed left ventricular systolic function after an acute myocardial infarction: a CARISMA substudy

Abstract Background The aim of this study was to investigate the clinically significant value of incidentally induced atrial fibrillation (AF) during programmed electrical stimulation (PES) in patients with left ventricular systolic dysfunction (≤40%) after an acute myocardial infarction (MI). Methods In this study we included 231 patients from the Cardiac Arrhythmias and RIsk Stratification after Myocardial InfArction (CARISMA) study. These patients were identified 3-21 days after being diagnosed with an MI, had left ventricular ejection fraction ≤40% and had no prior history of AF. They all received an implantable cardiac monitor (ICM) and were continuously monitored for cardiac arrhythmias for 2 years. A PES was performed 6 weeks post-MI with pacing from the right atrium and coronary sinus for induction of SVT and from the ventricular apex and outflow tract with up to three extra stimuli for induction of VT. Induction of AF was unwanted but reported if this incidentally occurred. Results AF was induced in 34 patients (15%) during the PES of which 10 (29%) later developed AF. A total of 61 patients (26%) developed AF within 2-years follow-up and the overall risk of AF was not significantly increased in patients with PES induced AF compared to patients without inducible AF (HR 1.6, P=0.14), however, the risk of AF ≤188 days post-MI was slightly increased (HR 3.0, P=0.01). The risk of bradyarrhythmia (HR=0.2, P=0.07), ventricular arrhythmias (HR=0.7, P=0.77) and MACE (HR 0.5, P=0.28) was reduced in patients with inducible AF compared to patients without inducible AF. Conclusions Incidentally induced AF during an electrophysiological study in post-MI patients was relatively frequent (15%) but was not associated with a higher risk of atrial fibrillation, other cardiac brady- or tachy-arrhythmias or major cardiac events. Even though the short-term risk for AF slightly increased, this does not seem to justify anticoagulation treatment or intensified follow-up in these patients.

Abstract 160: Atrial Fibrillation After Cardiac Arrest is Associated With Increased Risk of Mortality and Stroke

Introduction: The presence of atrial fibrillation (AF) in the first 2 days after resuscitation from cardiac arrest has been associated with increased mortality. However, whether new onset AF diagnosed in the first days to weeks after ROSC is associated with mortality or stroke is unknown. Our aim was to determine the incidence of new AF diagnoses after cardiac arrest and its impact on mortality and ischemic stroke. Methods: Retrospective observation cohort study using COSMOS, an Epic-based EHR database with &gt;190 million deidentified patients from 5/18/2020 to 4/1/2023. Patients with an ICD-10 diagnosis of cardiac arrest (ICD-10 I46.*) without prior history of AF were included. Two groups were examined: 1) AF diagnosis (ICD 10 I48*) made within 48 hours and 2) within 14 days after index cardiac arrest. We examined mortality and incidence of ischemic stroke at 1, 3, 6, and 12 months. Statistical comparisons were made using Chi-squared analysis. Results: Among 410,850 cardiac arrest patients without prior history of AF, 16,498 received a new AF diagnosis within 14 days (4%). The mean age was 68 yrs. with 64% male, 72% white. Mortality at one year in patients who developed AF by post-arrest day 14 was 54.5% vs. 39.5% in patients with no AF diagnosis (p&lt;.00001). The one-year incidence of stroke in patients with AF at 48 hours was 7.9%, similar to patients who had AF at 14 days (7.3%, p=NS). Moreover, stroke was diagnosed within 14 days of cardiac arrest in 5.4% of AF patients. Importantly, in these patients with stroke, 7% received anticoagulation with warfarin or direct oral anticoagulation, while the remaining 93% were not anticoagulated (p&lt;.00001), suggesting that consideration of early anticoagulation is imperative. Conclusion: AF diagnosed after cardiac arrest is associated with increased mortality. Patients who develop AF after cardiac arrest have significant short and long-term ischemic stroke risk, which is markedly decreased by anticoagulation. These data suggest that vigilance is required for patients who develop persistent AF after cardiac arrest, particularly stroke risk and prevention, as well as the consideration of an early rhythm control strategy.

Abstract 18368: Management of Incident AF in Hospitalized Patients - Deficient, Delayed, Detrimental

Introduction: Atrial fibrillation (AF) is potentially associated with significant complications including stroke and cardiac decompensation. Early appropriate AF management mitigates this risk. However, intervention is frequently delayed - a median of 1.5 days from AF onset in the ICU to clinical response. We sought to better understand delays in detection and management of AF in patients admitted to a cardiology bed and the consequences of delays. Methods: We undertook a retrospective review of 498 patients admitted to cardiology beds at the University of Virginia Medical Center who had automated algorithmic detection of AF episodes lasting ≥6 min. Time from algorithmic detection to clinical identification, AF burden, AF interventions and complications, medical history, and demographics were identified in each patient’s chart. Results: Of the 498 patients, 171 had an algorithmically detected episode of AF that was not acknowledged medically. These undetected episodes were generally shorter relative to episodes that were acknowledged (median 8 min vs. 52 min). 96 of the 498 patients had initial clinical detection of AF following algorithm detection; of the 96, 21 received early intervention (within 60 min), 51 received late intervention (after 60 min), and 24 received no intervention at all. Patients with early intervention experienced less AF burden compared to late and no intervention groups (median 8.6 hrs vs 21.75 hrs vs 29.35 hrs). Late intervention patients had more AF related complications compared to early intervention patients (9.8% vs. 4.8%). 20.8% of patients with clinical acknowledgement of AF but no intervention suffered a complication. Patients with a history of AF were more likely to have delays in intervention and over twice as likely to suffer an AF complication compared to those with no history (15.6% vs. 7.4%). Patients of lower socioeconomic status (SES) were also more likely to experience a complication. Conclusions: In summary, cardiology inpatients at our hospital commonly experience delays in management of AF that are considerable in duration, resulting in greater AF burden and higher complication rates. Differences in management, and subsequent outcomes, following AF appear to be impacted by prior history of AF and patient SES.

Abstract 12822: Prediction of New-Onset Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy Using RNA-Sequencing of Plasma Small Non-Coding RNAs

Background: It is known that about 20% of patients with hypertrophic cardiomyopathy (HCM) develop atrial fibrillation (AF), which can lead to stroke and worsening of heart failure. The current clinical model to predict new-onset AF in patients with HCM (HCM-AF score) offers only modest accuracy. RNA-sequencing (RNA-Seq) can determine concentrations of thousands of small non-coding RNAs (sncRNAs) in plasma. Hypothesis/Aims: To test the hypothesis that RNA-Seq of plasma sncRNAs predicts new-onset AF in HCM. Methods: In this prospective, multi-center cohort study, we conducted RNA-Seq of 3,740 plasma sncRNAs at enrollment on 283 patients with HCM without a prior history of AF. The outcome was new-onset AF. We developed a sncRNA-Seq-based LASSO classification model (sncRNA-Seq-based model) to predict new-onset AF using data from one institution (training set, n=193). We tested the predictive ability of the model in independent samples from the other institutions (test set, n=90). We also developed a clinical model with LASSO using all components of HCM-AF score - i.e., left atrial diameter, age, age at HCM diagnosis, and New York Heart Association functional class ≥2. We then compared the area under the receiver-operating characteristic curve (AUC) between the sncRNA-Seq-based model and the clinical model in the test set. Results: During a median follow-up of 2.8 [1.9-5.1] years, 25 patients (13%) in the training set and 7 (8%) in the test set developed new-onset AF. Using the sncRNA-Seq-based model developed in the training set, the AUC to predict new-onset AF in the test set was 0.82 (95% confidence interval [CI] 0.71-0.94, Figure ). This model outperformed the clinical model (AUC 0.59; 95% CI 0.38-0.81; Delong’s test P=0.02). Conclusion: This study serves as the first to demonstrate the ability of plasma sncRNA-Seq to predict new-onset AF in patients with HCM. The prediction model may help physicians identify patients with HCM who are at high risk of developing new-onset AF.

Incidence of cardiovascular and bleeding events and reasons for discontinuation in patients with chronic lymphocytic leukemia treated with ibrutinib-A retrospective analysis on consecutive patients from a well-defined region.

Ibrutinib treatment is associated with cardiovascular side effects, in particular atrial fibrillation (AF) and hypertension, as well as increased risk of bleeding. Here, we aimed at describing the incidence of these events during long-term follow-up in patients with chronic lymphocytic leukemia treated outside clinical trials as well as identifying clinical factors predictive of developing AF. Additionally, other reasons for treatment withdrawal were analyzed. The study was retrospective, data were collected from medical records. A total of 134 patients were identified. Median follow-up was 32 months (range 3-103) and median duration of ibrutinib treatment was 26 months (range 1-103). Of 110 patients with no prior history of AF, 24.5% were diagnosed during treatment. Newly diagnosed or worsening of pre-existing hypertension occurred in 15.7%. Sixty-six % of the patients experienced bleeding events, of which 7.5% grade 3-4. Treatment discontinuation and dose reduction occurred in 68% and 47% of the patients, respectively, mostly due to toxicity. The incidence of AF was high and at a median follow-up of 2.5 years, two-thirds of the patients discontinued treatment mostly due to bleeding and infections. Treatment-related toxicity of any grade should be regarded as a concern of prolonged ibrutinib therapy.

Active monitoring for atrial fibrillation (AMALFI): a streamlined randomised controlled trial of remote screening for subclinical atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health and Care Research Oxford Biomedical Research Centre ECG patches (and respective monitoring data analysis) were granted free of charge by the manufacturer (iRhythm) Background Incidence of stroke could be reduced by detection of subclinical atrial fibrillation (AF) and appropriate anticoagulation. Opportunistic screening by pulse-taking or ECG is recommended by some international guidelines. In contrast, there is uncertainty regarding the benefits and harms of systematic screening across populations and/or using longer monitoring durations. Purpose To assess if screening using a one-off single-lead continuous non-invasive ECG patch worn for 14 days increases AF detection at 2.5 years compared to standard care, and whether this approach is cost-effective. Methods AMALFI is an ongoing mail-based open-label randomised controlled trial of remote AF screening in England. Streamlined design includes integration with national electronic health data and care pathways for participant identification, invitation, and management. The target population are individuals aged ≥65 years with CHA2DS2VASc score of ≥3 in men and ≥4 in women, and with no prior history of AF or allergy to latex. Participants in the intervention arm self-apply the ECG patch and return it for analysis after 14 days. AF findings (duration ≥30 seconds at any rate) are communicated to primary care physicians, with further clinical management at their discretion. Participants in the control arm receive usual care (which is expected to include opportunistic AF screening). The primary outcome is the proportion of participants with newly-detected AF recorded in primary care electronic health records in each group at 2.5 years after randomisation. Results From 2019 to 2022, AMALFI invited 22,188 people, of whom 5,040 (23%) were randomised. Baseline characteristics included age 77±6 years, 47% female, and median CHA2SD2VASc score 3 (Table 1). Of 2520 individuals randomised to the intervention, 2127 (84%) wore and returned the patch. Median wear time was 13.9 days and median proportion of time analysable was 98.8%. AF was present in 102 patch reports, representing 4.8% of reports received and 4% of the intervention arm (in line with a priori estimates for power calculations for the primary outcome); median AF burden was 11.3%. AF was present at commencement of recording in 40% of these reports, by the end of the first day in 58%, and by the end of the first week in 83% (Figure 1). Incidental findings included supraventricular tachycardia (in 90% of reports), non-sustained ventricular tachycardia (VT; in 32%), sustained VT (in 0.1%), Mobitz II/high-grade/3rd degree AV block (in 1.1%), and pauses &amp;gt;6s (in 0.3%). Conclusion AMALFI’s innovative design facilitated recruitment and demonstrates that a remote ECG patch-based AF screening strategy is feasible, resulting in a new diagnosis of AF in ~4% of individuals selected due to moderate-to-high clinical stroke risk. Longer term follow-up will provide data on the incremental value and cost-effectiveness of AF diagnosis by systematic screening compared to routine opportunistic detection.

CE-452772-4 DELAYED DETECTION OF AND INTERVENTION FOR INCIDENT AF IN HOSPITALIZED PATIENTS IS COMMON AND CONSEQUENTIAL

Incident atrial fibrillation (AF) affects c.10% of hospitalized patients. Early AF management mitigates risk of complications (e.g. stroke, heart failure, care escalation) yet recognition and intervention is sub-optimal. Prior work here showed a median 1.5 day delay from automated algorithmic AF detection to clinical action in the ICU. The purpose of this work was to characterize AF recognition and intervention in cardiology floor patients, and the consequences of any delays. Retrospective review of 483 consecutively admitted patients from 12/24/20-12/20/21 having at least one algorithmically-detected significant AF episode (≥6 min duration = ‘clinically significant’). The algorithm uses multiple time and non-linear-domain characteristics of the time series data to ensure sensitive and specific AF detection. Characteristics of AF episode (Table 1), clinical response, and occurrence of prespecified AF-related complications were identified in patient charts, along with demographics and medical history. 34.2% (165/483) of patients had a clinically significant AF event that was missed. 20.3% (98/483) of patients had AF that was clinically detected after algorithmic detection. Within this group, 72 patients received clinical interventions: 21 received “early” interventions within one hour of AF onset; 51 received “late” interventions >1 hour after AF onset. 26 patients received no intervention despite clinical detection. 9.8% (5/51) of the late intervention patients experienced a complication, while 4.8% (1/21) of the early intervention patients experienced a complication. 19.2% (5/26) of patients clinically noted but with no intervention experienced a complication. Having a history of AF made likelihood of delayed intervention more likely [74.5% (38/51) vs 33.3% (7/21)]. Compared with caucasian patients, African American patients were less likely to receive early intervention for incident AF [24.1% (20/83) vs 0% (0/8)]. Despite widespread continuous cardiorespiratory monitoring, patients admitted to the cardiology floor of our tertiary hospital experience considerable and medically significant delays in the detection and management of incident AF. Delayed intervention results in higher complication rates. Having a prior history of AF and being African American were also associated with longer delays before AF intervention.

Incidence of stroke in patients with hypertrophic cardiomyopathy in stable sinus rhythm during long-term monitoring

IntroductionPatients with hypertrophic cardiomyopathy (HCM) are at increased risk of stroke, but the incidence and factors associated with cardioembolic events in HCM patients without atrial fibrillation (AF) remain unresolved. We determined the incidence of stroke in patients in sinus rhythm (SR) monitored with a cardiac implantable electronic device (CIED). MethodsAll consecutive patients diagnosed with HCM and referred to CIED implantation with >16 years at diagnosis and ≥ 1 year follow-up post CIED implantation were retrospectively reviewed. Severe LA dilatation was defined as ≥48 mm. Patients were stratified by rhythm as: Pre-existing AF (AF present prior to CIED); De novo AF (AF present after CIED implantation); SR: no episodes of AF. ResultsOf 1651 patients, 185 (11.2%) implanted with a CIED were included (57% men, age: 54 ± 17 years). Baseline, pre-existing AF was present in 73 (39%) patients. Ischemic stroke was reported in 19 (10.3%, 1.78%/year) patients and was similar across the three groups (2.3%/year vs 1.1%/year vs 0.6%/year in patients in SR vs pre-existing AF vs de novo AF, respectively, p = 0.235).In SR patients, a LAD≥48 mm posed the greatest risk of stroke (Hazard Ratio: 10.03,95% Confidence-Interval 2.79–16.01). At Cox multivariable analysis, after adjustment for oral anticoagulation, LA was independently associated with stroke while rhythm was not. Conclusionsin HCM patients with CIED long-term monitoring and no prior history of AF, stroke rates were similar in those with de novo AF or stable SR. Severe LA dilatation was a powerful risk factor, irrespective of AF.

Blood pressure status affects atrial fibrillation in diabetic end-stage renal disease.

The prevalence of atrial fibrillation (AF) is increasing as the elderly population continues to increase. Chronic kidney disease, diabetes, and hypertension are known risk factors for AF. Since multimorbidity exists in chronic kidney disease, it is difficult to determine the impact of hypertension alone. Furthermore, little is known about the impact of hypertension on predicting AF in diabetic end-stage renal disease (ESRD). Here, we evaluated the effect of differential blood pressure control on AF prevalence among the diabetic ESRD population. From the Korean National Health Insurance Service database, 2 717 072 individuals with diabetes underwent health examinations during 2005-2019. Exactly 13 859 individuals with diabetic ESRD without a prior history of AF were selected and included in the analysis. Based on blood pressure level and previous hypertension medication history, we subdivided them into five groups: normal (normotensive), pre-hypertension, new onset hypertension, controlled hypertension, and uncontrolled hypertension. AF risk according to the blood pressure groups was estimated using Cox proportional-hazards models. Among the five groups, the new onset hypertension, controlled hypertension, and uncontrolled hypertension groups showed a higher AF risk. In patients on antihypertensives, diastolic blood pressure ≥100 mmHg was significantly associated with AF risk. High pulse pressure showed a significant risk for AF in patients on antihypertensives. In patients with diabetic ESRD, overt hypertension and a history of hypertension impacts AF. AF risk was higher in the ESRD population with diastolic blood pressure ≥100 mmHg and pulse pressure >60 mmHg.

Lower heart rates and beta-blockers are associated with new-onset atrial fibrillation

BackgroundLower heart rates (HRs) prolong diastole, which increases filling pressures and wall stress. As a result, lower HRs may be associated with higher brain natriuretic peptide (BNP) levels and incident atrial fibrillation (AF). Beta-blockers may increase the risk for AF due to suppression of resting HRs. ObjectiveExamine the relationships of HR, BNP, beta-blockers and new-onset AF in the REVEAL-AF and SPRINT cohort of subjects at risk for developing AF. MethodsIn REVEAL-AF, 383 subjects without a history of AF and a mean CHA2DS2VASC score of 4.4 ± 1.3 received an insertable cardiac monitor and were followed up to 30 months. In SPRINT, 7595 patients without prior history of AF and a mean CHA2DS2VASC score of 2.3 ± 1.2 were followed up to 60 months. ResultsThe median daytime HR in the REVEAL-AF cohort was 75bpm [IQR 68–83]. Subjects with below-median HRs had 2.4-fold higher BNP levels compared to subjects with above-median HRs (median BNP [IQR]: 62 pg/dl [37−112] vs. 26 pg/dl [13–53], p < 0.001). HRs <75bpm were associated with a higher incidence of AF: 37% vs. 27%, p < 0.05. This was validated in the SPRINT cohort after adjusting for AF risk factors. Both a HR < 75bpm and beta-blocker use were associated with a higher rate of AF: 1.9 vs 0.7% (p < 0.001) and 2.5% vs. 0.6% (p < 0.001), respectively. The hazard ratio for patients on beta-blockers to develop AF was 3.72 [CI 2.32, 5.96], p < 0.001. ConclusionsLower HRs are associated with higher BNP levels and incident AF, mimicking the hemodynamic effects of diastolic dysfunction. Suppression of resting HR by beta-blockers could explain their association with incident AF.

Incidence and implications of atrial fibrillation in patients hospitalized for COVID compared to non-COVID pneumonia: A multicenter cohort study.

Atrial fibrillation (AF) has been reported to occur with coronavirus disease 2019 (COVID-19), but whether it is related to myocarditis or lung injury is unclear. The purpose of this study was to compare incident AF in patients with pneumonia/adult respiratory distress syndrome (ARDS) with and without COVID. This retrospective multicenter cohort study from 17 hospitals (March 2020 to December 2021) utilizing the University of California COVID Research Data Set (CORDS) included patients aged ≥18 years with primary diagnosis of pneumonia or ARDS during hospitalization. Patients with a history of AF were excluded. All subjects had documented COVID test results. Cohorts were compared using the χ2 test for categorical variables and the Wilcoxon rank test for continuous variables. Multivariable logistic regression models were used to investigate the association between COVID and development of new AF. Of the 39,415 subjects, 12.2% had COVID. The COVID+ cohort consisted predominantly of younger males with more comorbidities. Incident AF was lower in the COVID+ group than in the non-COVID group (523 [10.85%] vs 4899 [14.16%]; odds ratio [OR] 0.74; P <.001), which remained significant after adjustment for demographics and comorbidities (OR 0.71; P <.001). Patients had normal cardiac troponin levels. AF was related to intensive care unit care, pressor support, and mechanical ventilation, and was associated with higher mortality (26.2% vs 10.21%; P <.001) and longer hospitalization (22.5 vs 15.1 days; P <.001) in the COVID+ group compared to the controls. Incident AF is lower in COVID+ compared to non-COVID pneumonia/ARDS patients and seems to be related to severity of illness rather cardiac injury. AF was associated with higher mortality and prolonged hospitalization.

New atrial arrhythmia occurrence in single chamber implantable cardioverter defibrillator patients: A real-world investigation.

A current limitation of single chamber implantable cardioverter defibrillators (ICDs) is the lack of an atrial lead to reliably detect atrial fibrillation (AF) episodes. A novel ventricular based atrial fibrillation (VBAF) detection algorithm was created for single chamber ICDs to assess R-R variability for detection of AF. Patients implanted with Visia AF™ ICDs were prospectively enrolled in the Medtronic Product Surveillance Registry from December 15, 2015 to January 23, 2019 and followed with at least 30 days of monitoring with the algorithm. Time to device-detected daily burden of AF ≥ 6 min, ≥6 h, and ≥23 h were reported. Clinical actions after device-detected AF were recorded. A total of 291 patients were enrolled with a mean follow-up of 22.5 ± 7.9 months. Of these, 212 (73%) had no prior history of AF at device implant. However, 38% of these individuals had AF detected with the VBAF algorithm with daily burden of ≥6 min within two years of implant. In these 80 patients with newly detected AF by their ICD, 23 (29%) had a confirmed clinical diagnosis of AF by their provider. Of patients with a clinical diagnosis of AF, nine (39%) were newly placed on anticoagulation, including five of five (100%) patients having a burden >23 h. Continuous AF monitoring with the new VBAF algorithm permits early identification and actionable treatment for patients with undiagnosed AF that may improve patient outcomes.

An ECG-based machine learning model for predicting new-onset atrial fibrillation is superior to age and clinical features in identifying patients at high stroke risk

Background:Several large trials have employed age or clinical features to select patients for atrial fibrillation (AF) screening to reduce strokes. We hypothesized that a machine learning (ML) model trained to predict AF risk from 12‑lead electrocardiogram (ECG) would be more efficient than criteria based on clinical variables in indicating a population for AF screening to potentially prevent AF-related stroke.Methods:We retrospectively included all patients with clinical encounters in Geisinger without a prior history of AF. Incidence of AF within 1 year and AF-related strokes within 3 years of the encounter were identified. AF-related stroke was defined as a stroke where AF was diagnosed at the time of stroke or within a year after the stroke. The efficiency of five methods was evaluated for selecting a cohort for AF screening. The methods were selected from four clinical trials (mSToPS, GUARD-AF, SCREEN-AF and STROKESTOP) and the ECG-based ML model. We simulated patient selection for the five methods between the years 2011 and 2014 and evaluated outcomes for 1 year intervals between 2012 and 2015, resulting in a total of twenty 1-year periods. Patients were considered eligible if they met the criteria before the start of the given 1-year period or within that period. The primary outcomes were numbers needed to screen (NNS) for AF and AF-associated stroke.Results:The clinical trial models indicated large proportions of the population with a prior ECG for AF screening (up to 31%), coinciding with NNS ranging from 14 to 18 for AF and 249–359 for AF-associated stroke. At comparable sensitivity, the ECG ML model indicated a modest number of patients for screening (14%) and had the highest efficiency in NNS for AF (7.3; up to 60% reduction) and AF-associated stroke (223; up to 38% reduction).Conclusions:An ECG-based ML risk prediction model is more efficient than contemporary AF-screening criteria based on age alone or age and clinical features at indicating a population for AF screening to potentially prevent AF-related strokes.

Incidence of atrial high rate episodes after dual-chamber permanent pacemaker implantation and its clinical predictors

Atrial high rate episodes (AHRE) confers increased morbidity and mortality amongst patients with permanent pacemaker implantation (PPI). The incidence of AHREs and it's clinical predictors in Indian patients without prior history of atrial fibrillation (AF) are not well understood. A total of 100 dual-chamber PPI patients, who had no prior history of AF, underwent pacemaker interrogation starting from a minimum of 1 month after implantation to detect any AHREs. The incidence of AHREs was 17% at a mean follow up 15.2 ± 7.5 months. Only right ventricular apical lead position was found to have an independent association with AHREs (OR: 3.50, 95% CI: 1.02–12.03; p = 0.04).

Critical illness associated new onset atrial fibrillation: subsequent atrial fibrillation diagnoses and other adverse outcomes.

Amongst patients with critical illness associated new onset AF (CI-NOAF), the risk of subsequent atrial fibrillation (AF) diagnoses and other adverse outcomes is unknown, and the role for long-term anticoagulation is unclear. This study sought to determine the factors associated with subsequent AF diagnoses and other adverse outcomes in this cohort. Admissions to a tertiary general intensive care unit (ICU) between December 2015 and September 2018 were screened for AF episodes through hourly analysis of continuous ECG monitoring. Patients with a prior history of AF were excluded. AF burden was defined as the percentage of monitored ICU hours in AF. The primary endpoint was subsequent AF diagnoses, as collated from the statewide electronic medical records. Secondary endpoints included mortality, embolic events, MACE and subsequent anticoagulation. Of 7030 admissions with 509 303 h of monitoring data, 309 patients with CI-NOAF were identified, and 235 survived to discharge. Subsequent AF diagnoses were identified in 75 (31.9%) patients after a median of 413 days. Increased AF burden had the strongest independent association with AF recurrence (OR = 15.03, P = 0.002), followed by increased left atrial area (OR = 1.12, P = 0.01). Only 128 (54.5%) patients had their AF diagnosis acknowledged at ICU discharge, and 50 (21.3%) received anticoagulation at hospital discharge. CI-NOAF is often under-recognized, and subsequent AF diagnoses are common post-discharge. AF burden during ICU admission has a strong independent association with subsequent AF diagnoses. Left atrial size is also independently associated with subsequent AF.

Atrial fibrillation in COVID-19 patients admitted to an intensive care unit: prevalence and prognosis

Abstract Background The association between atrial fibrillation (AF) and prognosis has been studied in non-COVID-19 patients, but few studies reflect the reality of critically ill COVID-19 patients admitted to a general intensive care unit (ICU). Purpose This study sought to investigate the relationship between previous and new-onset AF in COVID-19 patients admitted to an ICU and prognosis. Methods We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19 and followed them for a median period of 7 months. Patients admitted due to trauma or emergent surgery were excluded from the analysis. Three groups were identified: without AF (G1), with prior history of AF (G2), and with new-onset AF (G3). Groups were compared, with special interest regarding ICU mortality, duration of mechanical ventilation, length of hospitalization, major adverse cardiac events (MACE), and re-hospitalization. MACE was defined as all-cause ICU mortality, new-onset heart failure, acute coronary syndrome, ventricular arrhythmias, pulmonary embolism, myocarditis, and stroke (ischemic or hemorrhagic). Results A total of 297 patients was included in the analysis: without AF (248 patients, 83.5%), with prior history of AF (15 patients, 5.1%), and with new-onset AF (34 patients, 11.4%). Median age was 62 (IQR 17) years, and most patients were male (198 patients, 66.7%). Patients with a prior history of AF were older [median (IQR), G1 60 (16), G2 71 (12), G3 67 (15) years, p=0.001], were more likely to have a history of coronary artery disease (G1 4.9%, G2 26.7%, G3 11.8%, p=0.002), and history of heart failure (G1 6.5%, G2 33.3%, G3 17.6%, p&amp;lt;0.001). Patients with new-onset AF had a longer duration of mechanical ventilation [median (IQR), G1 9 (13), G2 11 (16), G3 18 (12) days, p&amp;lt;0.001), longer ICU length of stay [median (IQR), G1 12 (10), G2 13 (12), G3 19 (15), p=0.001], higher ICU mortality rate (G1 27.0%, G2 33.3%, G3 58.8%, p=0.001), and higher rate of MACE (G1 31.9%, G2 33.3%, G3 70.6%, p&amp;lt;0.001), compared to the other groups. There were no differences regarding sex distribution, other baseline comorbidities, need for invasive mechanical ventilation, vasopressor use, and re-hospitalization rates among groups. Most AF patients were treated with beta-blockers (39.6%) and amiodarone (77.1%), but only 68.8% of patients received anticoagulation (G2 92.9%, G3 58.8%), which may reflect that physicians underestimate the prognosis of new-onset AF. In multivariate analysis, new-onset AF (OR 3.07, 95% CI 1.42–6.67, p=0.005) and older age (OR 1.07, 95% CI 1.04–1.09, p&amp;lt;0.001) remained independent predictors of ICU mortality. Main results are presented in Table 1. Kaplan-Meier survival curves are presented in Figure 1. Conclusion(s) This study shows that critically ill COVID-19 patients with AF present a worse prognosis compared to patients without AF, and new-onset AF is an independent predictor of ICU mortality and MACE. Funding Acknowledgement Type of funding sources: None.

Incidence of stroke in patients with hypertrophic cardiomyopathy in stable sinus rhythm during long-term monitoring

Abstract Background Patients with hypertrophic cardiomyopathy (HCM) are at increased risk of atrial fibrillation (AF) and stroke, especially at an advanced disease stage. To date, however, the incidence and factors associated with cardioembolic events in HCM patients without AF remain unresolved. Purpose To determine the incidence of stroke in HCM patients in whom cardiac rhythm was monitored with a cardiac implantable electronic device (CIED). The association of stroke with left atrial (LA) enlargement was also examined. Methods Retrospective cohort study in an outpatient clinic in a tertiary HCM Referral Center. All consecutive patients diagnosed with HCM and referred for CIED implantation with &amp;gt;16 years at diagnosis and &amp;gt;1 year follow-up post CIED implantation were reviewed. Severe LA dilatation was defined as a LA dimension (LAD) of &amp;gt;48mm at echocardiogram. Based on CIED monitoring, patients were classified as: Pre-existing AF (diagnosed with AF prior to CIED); De novo AF (diagnosed with AF after CIED implantation); Sinus Rhythm (SR): no episodes of AF. Incidence of stroke after CIED implantation was the primary outcome. Results A total of 185 patients (57% men, age: 54±17 years) were implanted with a CIED and were included. Pre-existing AF was present in 72 (36%) patients and de novo AF in 24 (13%); whereas 89 (48%) remained in SR. After 5 [2–9] years, stroke was reported in 19 (10.3%) patients: 7 occurred in patients with pre-existing AF (1.1%/year), 3 in patients with de novo AF (2.2%/year), and 9 in patients with SR (2.3%/year). No difference was captured by CHA2DS2-VASc score among rhythm categories. Patients with AF had larger LAD at baseline. Among patients in SR, those with a LAD&amp;gt;48mm had the greatest risk of stroke (4.8%/year vs 0.5%/year, p&amp;lt;0.01; Hazard Ratio [HR]: 8.56, 95% C.I. 2.03–36.15). At Cox multivariable regression analysis, LA (HR: 1.104, 95%C.I. 1.039–1.173, p=0.001) and AF (HR: 0.310, 95% C.I. 0.102–0.939, p=0.038) were associated with incident stroke. Conclusions In HCM patients with CIED long-term monitoring and no prior history of AF, stroke rates were similar in those with de novo AF or stable sinus rhythm. CHA2DS2-VASc considerably underestimated risk, whereas severe LA dilatation was a powerful predictor of risk, irrespective of AF. Funding Acknowledgement Type of funding sources: None.

Left atrial reservoir strain and long-term prognosis in patients with heart failure and reduced ejection fraction

Abstract Background Cardiac damage in heart failure (HF) with reduced ejection fraction (HFrEF) often involves structural and functional left atrial (LA) abnormalities. Speckle-tracking echocardiography derived LA reservoir strain (LARS) is a sensitive measurement for early detection of LA dysfunction. However, the prognostic value of LARS is not well established in patients with HFrEF. Methods LARS was measured with speckle tracking echocardiography in patients who had a first echocardiographic diagnosis of reduced LVEF (≤45%). Patients with prior history of atrial fibrillation (AF) were excluded. The primary endpoint was newly onset AF, while the composite endpoint of newly onset AF and all-cause mortality was chosen as the secondary endpoint. The study population was divided into two groups according to the optimal threshold value of baseline LARS (derived from spline curve analysis) (Figure 1) and event-free survival rates were compared by the Kaplan-Meier method. Results A total of 997 patients (mean age 62±13 years, 73% men) were analyzed. At baseline, LA volume index was significantly larger (41±17 vs. 32±12 ml/m2, p&amp;lt;0.001), and LA reservoir function significantly more impaired (9±3.1 vs. 21±6.3%, p&amp;lt;0.001) in patients with LARS ≤14% compared to patients with LARS &amp;gt;14%. During a median follow-up of 60 months (interquartile range [IQR] 29–60 months), newly onset AF occurred in 75 patients (7.5%), while 254 patients (25.5%) experienced the composite endpoint of newly onset AF and all-cause mortality. The 5-year event-free survival rates for both endpoints were significantly lower in the LARS ≤14% group compared to LARS &amp;gt;14% group (Figure 1A for new onset AF and Figure 2B for the composite endpoint of newly onset AF and all-cause mortality). After adjustment for important risk factors, including HF treatments and echocardiographic predictors, baseline LARS remained independently associated with a higher risk of development of AF (HR=0.89, 95% CI 0.85–0.94, p&amp;lt;0.001) and the composite of newly onset AF and all-cause mortality (HR=0.93, 95% CI 0.91–0.96, p&amp;lt;0.001). Conclusions Baseline LARS is associated with long-term prognosis in patients with HFrEF and the association is independent from various clinical and echocardiographic predictors. Funding Acknowledgement Type of funding sources: None.