Cardiac Monitoring Research Articles

Incidence of atrial fibrillation detected by an insertable cardiac monitor in a large real-world cohort of heart failure patients with reduced and preserved ejection fraction

Abstract Background Subcutaneous implantable cardiac monitors (ICM) have the capability to detect atrial fibrillation (AF) episodes with high degree of accuracy [1]. Objective We investigated the incidence of AF in patients implanted with an ICM and a clinical history of heart failure (HF) with reduced or preserved left ventricular ejection fraction (LVEF). Methods Patients with history of HF admissions who were implanted with an ICM were identified from the aggregated and de-identified electronic health record (EHR) database during 2007-2021. The device collected data were merged with the EHR data to create a de-identified database of real-world patients. Patients were included if they had ≥180 days of device follow-up. ICMs detect AF based on incoherence of RR intervals and absence of single p-wave between two R-waves [1]. All ICM detected AF episodes stored with at least 30 seconds of ECG at onset were adjudicated using an artificial intelligence (AI) model. The AI model was previously trained and validated using over 60K manually adjudicated episodes and was shown to have an accuracy of over 97% [2]. ICM detected AF episodes with AI model based true probability of AF ≥ 0.9 was analyzed. The Kaplan-Meier incidence curves for AF incidence as a function of episode duration, clinical history of AF, and LVEF are reported. Results A total of 1020 LINQ ICM patients with history of HF admission prior to implant were identified from the deidentified real-world dataset. LVEF was available in 889 (87%) patients, of whom 394 (44%) had EF <50%, and 495 (56%) had EF≥50%. NYHA class was available in 296 (29%) patients, of whom 39 (13%) were class I, 126 (43%) were class II, 112 (38%) were class III, and 19 (6%) were class IV. Patients had an average age of 68±13 years with 52% being males and had clinical history of hypertension in 95%, diabetes in 56%, coronary artery disease in 75%, AF in 57%, stroke/TIA in 51%, and renal dysfunction in 53%. A total of 911 patients with ≥180 days of follow-up (average follow-up of 25.8 months) were included. A total of 8407 episodes from 358 patients were classified by the AI model as true AF. The incidence of AF as a function of episode duration, clinical history of AF and reduced vs preserved LVEF are shown in Figures A, B, and C respectively. Incidence of AF, as detected by an ICM over 42 months of follow-up, was estimated to be 38% to 46% depending on AF episode duration. Estimated 42-month AF incidence was 23% in patients with no clinical history of AF. The 42-month AF incidence was 44% vs 47% in HF patients with reduced versus preserved LVEF. Conclusion Incidence of AF, as detected by an ICM over 3 years of follow-up, was estimated to be in close to half of ICM patients with history of HF events. Close to one fourth of the patients with no prior clinical history of AF had newly detected AF. AF incidence was similar in HF patients with preserved versus reduced LVEF in this real-world cohort.

Clinical validated risk prediction model for development of heart failure after contemporary breast cancer treatment

Abstract Background Patients receiving breast cancer (BC) treatment are at risk for heart failure and cardiomyopathy (HF/CM). European Society of Cardiology (ESC) cardio-oncology guidelines recommend baseline cardiovascular (CV) assessment, however, there is limited data about cardiotoxicity risk specific to patients with BC. Our aim was to develop and validate model for prediction of HF/CM in women receiving contemporary treatment for invasive early-stage BC. Methods We assembled a cohort women diagnosed with Stage I-III BC from 2008-2020 and followed through 2021 in a large health care plan. Women age >80, with history of HF/CM, and women who received both anthracyclines and trastuzumab were excluded, leaving N=26,044 for analysis. Study cohort was randomly split into derivation (60%) and validation (40%) datasets. Elastic-net penalized Cox proportional hazard model was created using the derivation dataset to select risk factors and to calculate the panelized coefficient which defined the HF/CM risk score. Risk score system was assessed by Hosmer-Lemeshow goodness-of-fit test and area under the ROC curve (AUC). Event rates of <5% constituted low risk; 5-14% moderate; and >15% high risk category. Incident HF/CM events were examined using Kaplan-Meier approach in derivation and validation datasets. Results HF/CM risk score had high discrimination ability and sufficiently good model of fit regarding HF/CM events (P value=0.163 and 0.667 from Hosmer–Lemeshow test;AUC 0.751 and 0.764, in derivation and validation sets, respectively). There were 10% of women in the high risk; 30% in moderate; and 60% in low-risk group. Variables associated with the higher HF/CM risk score included age, receipt of anthracycline-based chemotherapy or anti-HER2 therapy, presence of hypertension, diabetes, or history of other CV conditions at baseline. The score pattern showed major effect of age, with anthracycline and anti-HER2 therapy increasing the risk across all age groups (Figure 1). Kaplan-Meier analysis of incident HF/CM over 14 years after BC diagnosis showed significantly lower number of HF/CM events in low risk compared to moderate and high-risk score groups (p<0.0001, Figure 2). Conclusion Our robust risk prediction model for HF/CM among women with early-stage BC provides a new tool to identify women at higher CV risk and inform cardiac function monitoring during and after BC treatment. Our findings may guide further validation studies and build evidence for the cardiotoxicity risk stratification in patients with BC.Risk Score for HF/CM by Age/ChemoTxK-M curves of freedom from HF/CM

Cost impact of the use of a universal cardiac implantable electronic devices remote monitoring solution: results of the Evidence RM study

Abstract Background Remote monitoring (RM) is considered the standard of care for patients with cardiac implantable electronic devices (CIED). In 2023 the HRS/EHRA/APHPRS/LAHRS expert consensus highlighted the potential interest of alert-based monitoring and the use of a third-party platform for RM management. By lightening the RM workload for clinical staff, valuable time and resources can be redirected towards patient care. Purpose This study aims to assess the impact on healthcare expenditures of the adoption of a Universal, vendor-neutral, and alert-focused remote monitoring (RM) platform for CIED in France, as opposed to the Conventional RM conducted via device specific manufacturers' platforms. Methods This study utilizes the French National Health Database (SNDS) to evaluate the effectiveness of RM solutions among patients with implantable cardioverter defibrillators (ICD), including cardiac resynchronization therapy defibrillators (CRT-D). All patients under RM were categorized based on the type of monitoring, either the Universal RM or the Conventional RM. The analysis was conducted on year 2019 and included only patients maintaining consistent RM solutions and device types throughout the entirety of the study period. To mitigate potential biases, costs were adjusted according to age, gender, device type, year of first implantation, year of RM initiation, medical center experience with RM, and Elixhauser score for comorbidities. Results Study cohort consisted of 36,401 patients (age 67.3 ± 13.0 years / male 78.4% / CRT-D 40.1%), 1,482 patients followed using the Universal RM platform and 34,419 patients monitored with the Conventional RM solutions. The study findings revealed a 4% decrease in corrected total costs and a notable 17.8% reduction in hospital costs among patients utilizing the Universal RM. Analysis further identified that this decrease in hospital expenses was primarily influenced by a reduction of the costs associated with cardiovascular diseases. Conversely, the group utilizing the Universal RM experienced a 7.9% increase in total outpatient costs compared to Conventional RM, while ambulatory visit costs remained unchanged. As costs incurred by patients were not included, total costs may however be underestimated. Patients under the Universal RM solution may benefit of more proactive preventive measures delivered through outpatient care. By addressing issues preemptively, critical conditions may be averted, enhancing overall patient management, and diminishing hospital costs. The adoption of a third-party Universal platform may thus yield to cost savings, exemplified by a negative Incremental Cost-Effectiveness Ratio (ICER) of -103€ per Day Alive and Out of Hospital (DAOH) as observed in this study. Conclusions The use of a third-party Universal RM platform showed a positive impact in terms of costs reduction for the French healthcare system on this ICD population.

A new wearable cardiac acoustic monitoring technology for the evaluation of subclinical leaflet thrombosis after transcatheter aortic valve replacement: a pilot study

Abstract Background Subclinical leaflet thrombosis characterized by hypoattenuated leaflet thickening (HALT) and reduced leaflet motion (RLM) is a common complication after transcatheter aortic valve replacement (TAVR), whether it affects hemodynamic change is still debated. Purpose We attempted to use a novel wearable heart acoustic monitoring device, and combined multi-dimensional computed tomography (MDCT) and echocardiography to diagnose SLT and analyze the changes of transvalvular hemodynamics after TAVR. Methods Patients with severe symptomatic aortic stenosis and underwent successful TAVR were consecutively enrolled. Clinical data, acoustic cardiographic parameters including the frequency, amplitude, and energy of heart sounds , and imaging results were collected and analyzed by Core laboratory at pre- and post TAVR, and follow-up at one month and six month. According to severity of SLT at one month follow-up, we divided the patients into three groups: Group1: no SLT, Group2: mild SLT, defined as existed HALT did not qualify for Group 3, and Group 3: moderate to severe SLT, defined as at least 1 leaflet with HALT of grade 3 or 4 or RLM of ≥50%, or 2 leaflets with HALT of grade 2 or RLM of ≥50%. A consistency analysis of SLT presence between MDCT findings and acoustic cardiographic variables was performed using Kappa statistics. Results The study included 116 TAVR patients. The prevalence of SLT as detected by MDCT at one-month follow-up was 25%, with moderate to severe SLT representing 11.2% of cases. A significant decrease in aortic valve orifice area (AVA) (-0.2±0.48cm2 vs. -0.1±0.33cm2, p=0.009) and an increase in mean gradient (MG) (3.5±5.85 mmHg vs. 0.1±11.34mmHg, p=0.028) were observed in moderate to severe SLT group at one-month follow-up versus post-TAVR via echocardiography. However, no significant differences were found in the mild SLT or no SLT group. Acoustic cardiographic characteristics exhibited a distinct pattern with early systolic, baseless, and high-energy murmurs in patients with moderate to severe SLT, but not in the mild SLT or no SLT group. The sensitivity, specificity, and Kappa values for acoustic cardiography in diagnosing moderate to severe SLT were 81.82%, 83.33%, and 0.41, respectively. At the 6-month follow-up, MDCT showed that 11 (85%) patients with moderate to severe SLT who received anticoagulant therapy reached complete dissolution of SLT. Conclusion Moderate to severe SLT presented notably transvalvular hemodynamic influences following TAVR. Acoustic cardiography demonstrated specific characteristics of moderate to severe SLT, providing a valuable tool for SLT diagnosis and evaluation in clinical follow-up.Figure 1.Baseline characteristicsFigure 2.SLT and acoustic cardiography

To monitor or not after detected AF, this is a question: report from the consumer-led screening programme of long-term extension mAFA cohort

Abstract Background The consumer-led screening for atrial fibrillation (AF) is evolving with the widespread availability of wearables. Nonetheless, what the long-term impact on the individual's behavior of rhythm monitoring after detected AF is unclear. Objective To investigate the long-term impact on health behavior for the individuals using wearables for cardiac rhythm. Methods In the mobile technology supported screening and integrated care in atrial fibrillation (mobile atrial fibrillation application, mAFA programme), the general population freely decided to enter the screening programm with wristbands or watches across China. At least 14-day monitoring was proposed, the individuals with detected AF can consider to receive the mAFA App for AF care. The adherence of rhythm monitoring after detected AF with wearables was calculated, while the multinomial logistics regression model was utilised to analyze the independent factors associated with the adherence. Results There were 4337172 individuals entered into AF screening programme using wearables between Oct, 2018 and Feb 14, 2024. Among them, 22224 individuals (0.5%, 22224/4337172, mean age, SD, 55, 16 years old, male 82.4%) were monitored with AF episodes. There were 21223 individuals remaining the wearables use for rhythm monitoring after first AF identification. The time (days, median, interquartile ) using wearables for monitoring the pulse rhythm were 465 (130, 889) days. The time to first identified AF (days, median, interquartile) were 16 (1, 176) days. The continuing monitoring time since first identified AF (days, median, interquartile) were 290 (54, 668) days. The adherence of cardiac rhythm monitoring after detected AF with wearables (Figure): 96.0% individuals continued the rhythm monitoring using wearables during 30 days, 58.8% in 2 years, and 35.7% in 3 years and over. In the adjusted multinomial logistics regression model, the palpitation, hypertension, obstructive sleep apnea, heart failure, age and mAFA use were independently associated with the adherence for the individuals remaining the wearables use for rhythm monitoring after detected AF (all p<0.05). Conclusions The general population at risk were likely to receive long-term rhythm monitoring after detected AF, and the mAFA use, with the self-care support, was an independent factor for the continuing monitoring.

Next-generation public health surveillance: extreme heat event prediction and monitoring system

Abstract Background Extreme Heat Events (EHEs) are a growing threat to public health. The increase in the frequency of occurrence of once rarer EHEs and the rise in their average temperatures are dangerously drastic for public health outcomes. Despite this, existing public health surveillance (PHS) systems fail to leverage IoT and AI technologies to facilitate real-time, continuous monitoring of EHE indicators and its associated health risks. This study closes this gap by proposing a comprehensive PHS system that can, in real-time monitor and predict EHE indicators to provide timely alerts to public health authorities. Methods The EHE PHS system collects EHE detection metrics, including indoor temperature and humidity levels, from IoT sensors and thermostats to map them across Canada, primarily focusing on low-income communities. The system also integrates historical climate data (surface temperature, humidity, wind speed and direction, and air quality indicators) from Environment Canada. The system uses the data to train initial prediction models including CNN, LSTM and GNN. The validated model will be integrated into the system, enabling real-time EHE prediction. The output will be displayed in user-friendly visualizations on the EHE PHS system’s dashboard capabilities. Results The system allows for the analysis of real-time data through dashboards and provides alerts when certain indicators (e.g. excessive or prolonged heat) detrimental to public health outcomes are detected. The alerts enable valuable lead time for public health authorities to implement proactive measures, such as issuing heat advisories and deploying resources to vulnerable areas. Conclusions The EHE PHS system will serve as a blueprint for global public health researchers, utilizing IoT and AI technologies for proactive crisis prevention. This knowledge will inform the development of heat-resilient policies and set a precedent for global public health crisis prevention. Key messages • The proposed EHE PHS system uses AI and IoT technologies, to enhance EHE prediction, risk identification, and real-time monitoring for effective public health interventions. • By integrating advanced predictive models and environmental data, the system facilitates early detection of EHE risk, which can significantly mitigate the health impact on vulnerable populations.

How can the detection of AF be improved? Insights from patient journeys and primary care clinicians

Abstract Background Atrial fibrillation (AF) is underdiagnosed and it is estimated that a third of people with AF remain undiagnosed. AF is complex to detect because it can be intermittent and some patients are asymptomatic. When symptoms are present they can be non-specific. In the absence of a screening programme to detect AF it is important to identify ways to improve its detection of AF in order to reduce the risk of AF-related stroke. Purpose We conducted a qualitative study in primary care to explore the patient path to diagnosis of AF and identify ways to improve detection Methods We recruited patients with a recent diagnosis of AF (< 6 months) and interviewed them to understand their path to diagnosis. We interviewed GPs and practice nurses to explore their experience of detecting AF in primary care. The interviews were audio-recorded and transcribed, and the data were analysed using framework analysis. Results Thirty patients and ten primary care clinicians were interviewed. The presence and nature of symptoms experienced by patients and how they interpreted these were significant in the pathways to diagnosis. Patients with acute symptoms presented to A &E and had a quick diagnosis while asymptomatic patients were diagnosed incidentally. Patients with non-specific symptoms generally did not perceive the symptoms as serious, and many delayed seeing a healthcare professional. Their experiences in primary care aligned with findings from interviews with primary care clinicians, who acknowledged AF may not necessarily be the initial suspicion when a patient presents with certain non-specific symptoms. Primary care clinicians described narratives of good practice in the form of opportunistic pulse palpation, as well as challenges of detecting AF in primary care. These included lack of access to 24-hour ambulatory ECG in primary care and limited opportunities to detect AF due to healthcare assistants taking on more responsibilities. Conclusions A number of opportunities to improve the detection of AF can be drawn from these findings. Public education about AF, its signs and symptoms would increase patient knowledge and presentation to healthcare professionals. Standardizing good practice of opportunistic pulse palpation in primary care and training healthcare assistants to perform this is also indicated. Access to 24-hour ambulatory ECG in primary care will reduce delays in diagnosis. Further research on which patients are likely to have undiagnosed AF will facilitate detection in primary care.

Quality of life measures with etripamil self-administration for acute episodes of paroxysmal supraventricular tachycardia in a medically unsupervised setting: patient-reported outcomes from NODE-303

Abstract Background Etripamil nasal spray (NS) is a fast-acting, self-administered calcium-channel blocker in development for the conversion of AV-nodal dependent paroxysmal supraventricular tachycardia (PSVT) in a medically unsupervised setting. Prior studies show favorable safety and efficacy in converting single episodes of PSVT to sinus rhythm (SR). Purpose In NODE-303, patient-reported outcome (PRO) instruments assessed quality of life (QoL) over multiple etripamil-treated episodes of PSVT. Methods NODE-303 was an event-driven, multi-center, open-label Phase 3 study in North and South American patients with documented PSVT that evaluated the safety and efficacy of etripamil in PSVT termination, over multiple episodes and without the need for prior test dosing. Enrolled patients who perceived PSVT symptoms applied an ambulatory ECG cardiac monitoring system (CMS), performed a pre-trained vagal maneuver and, if symptoms persisted, self-administered etripamil NS 70 mg. A study amendment allowed a repeat dose (etripamil NS, 70 mg) if symptoms persisted 10 min after the first dose. Each patient could self-treat up to 4 episodes. Safety was assessed through adverse events, clinical data, and ECG CMS recordings. The Treatment Satisfaction Questionnaire for Medication (TSQM; validated for acute episodic assessments) and other PROs were administered, and healthcare utilization data were acquired. Patients completed PROs at baseline (BL), monthly, and per PSVT episode, which collected information on symptoms, episode characteristics, rescue medications, and emergency room visits. Additional PROs were the Brief Illness Perception Questionnaire (BIPQ), Cardiac Anxiety Questionnaire (CAQ), and 36-Item Short Form Health Survey (SF-36). Results There were higher proportions of patients reporting mild, minimal or no disease severity, every 6 months, than at BL; extremely severe, severe, and moderate disease severity was reported by smaller proportions of patients than at BL, though incomplete surveys at later visits may limit this analysis. Anxiety and stress about future PSVT episodes were consistently reduced from BL. Measures of treatment satisfaction, effectiveness, and convenience were consistent across multiple episodes, and were at levels considered favorable for the TSQM instrument (Table 1). Rates of emergency-room visits and hospital admissions across multiple, treated PSVT episodes were similar to those observed in trials assessing single episodes (Table 2). The BIPQ, CAQ or SF-36 had no notable changes from BL. Conclusions Etripamil self-administration was associated with patient-reported improvements in degree of disease severity, decreased anxiety and stress over future PSVT episodes, and levels of treatment satisfaction, effectiveness, and convenience considered favorable for respective PRO instrument. Using a symptom-prompted, self-administered treatment for PSVT could potentially improve QoL measures and reduce healthcare resource utilization.

Evaluating the feasibility of upper arm ECG for cardiac monitoring

Abstract Background Ambulatory electrocardiogram (ECG) monitoring is essential for detecting paroxysmal cardiac events and tracking long-term physiological parameters. However, traditional Holter devices are cumbersome, restrict movement, and can cause skin irritation, resulting in sub-optimal patient compliance during extended monitoring periods. Wearable devices utilizing non-conventional form factors are emerging as promising non-intrusive alternatives for ECG monitoring. Purpose To determine the optimal location for single-lead ECG acquisition on the upper arm and assess the feasibility of using dry electrode armbands for cardiac monitoring when coupled with robust ECG processing software. Methods Stationary ECGs from 20 healthy adult participants were recorded across a two-phase data collection protocol and processed with clinically validated ECG software. In the first phase, the average signal amplitudes of wet-electrode ECGs obtained from 30 different configurations across the mid-brachial and proximal-brachial regions of the upper arm were assessed. In the second, the performance of two proprietary dry-electrode armbands, featuring either a single-point or three-point electrode strap, were evaluated on the optimal upper arm configuration using QRS detection and heart rate (HR) metrics. Comparative analysis was performed throughout using data simultaneously acquired on a gold standard Holter device in modified lead III (MLIII) configuration. Performance metrics were calculated relative to manually generated signal annotations. Results Wet-electrode-acquired ECGs from the proximal-brachial region exhibited significantly higher average signal amplitudes (0.12 ± 0.06 mV) compared to those from the mid-brachial region (0.05 ± 0.04 mV) of the upper arm (p < 0.05). The optimal configuration (A-F), positioned at the lateral and medial extents of the proximal-brachial region, demonstrated comparable average signal amplitudes (0.16 ± 0.07 mV, 0.16 ± 0.06 mV, 0.19 ± 0.08 mV) for single-point dry, three-point dry, and wet-electrode setups, respectively. Upon processing with ECG software, data from optimal dry-electrode configurations showed excellent average QRS sensitivity and specificity of 98.2% and 98.9% for the one-point strap, and 98.9% and 99.8% for the three-point strap, respectively. HR metrics from the optimized dry-electrode setups were comparable in accuracy to those derived from the reference Holter device, with the average HR error being similar across the three-point dry electrode strap (0.57% ± 0.28%), one-point dry electrode strap (1.16% ± 1.46%), and Holter device (0.74% ± 1.50%). Conclusion(s) Optimized upper arm single-lead ECG with dry electrodes can yield signals with sufficient amplitude and quality for automated ECG analysis. Coupled with robust ECG signal processing software, the cardiac metrics obtained from the optimized upper arm setups exhibited comparable performance to those derived from medical Holter data.

Impaired myocardial energetics in both sarcomere positive and negative HCM are linked to arrhythmic risk

Abstract Background Impaired myocardial energetics play a pivotal role in the complex pathophysiology of hypertrophic cardiomyopathy (HCM), and are thought to be mediated by energy-costly sarcomeric mutations and mitochondrial dysfunction (1). Two thirds of HCM patients, however, do not possess pathogenic sarcomeric mutations (2) and instead develop the condition due to a combination of increased polygenic susceptibility and comorbidities. Whether energetic impairment, a target of novel HCM treatments (e.g., myosin modulators such as Mavacamten), similarly affects sarcomere mutation positive (Sarc+) and negative (Sarc-) HCM remains unclear, as does the association between impaired energetics and markers of arrhythmic risk such as hypertrophy severity, cardiac function and non-sustained ventricular tachycardia (NSVT). This study aimed to investigate differences in resting myocardial energetics between Sarc+ and Sarc- HCM by measuring the phosphocreatine-to-adenosine triphosphate (PCr/ATP) ratio using phosphorus magnetic resonance spectroscopy (31P-MRS) and explore the association between impaired energetics and markers of arrhythmic risk in HCM. Methods We recruited one hundred (100) participants (80 non-obstructive HCM patients and 20 age- and sex-matched controls). Myocardial energetics were assessed using 31P-MRS to measure the PCr/ATP ratio. Cardiac magnetic resonance (CMR) imaging including cine, T1 (ShMOLLI), quantitative pixel-wise perfusion mapping (3) and late gadolinium enhancement (LGE) imaging was also performed. In addition, HCM patients underwent 7-day ECG monitoring to document NSVT episodes (3 beats ≥120 bpm). Results HCM patients had impaired myocardial energetics (PCr/ATP ratio) relative to controls (HCM 1.64±0.36 vs controls 1.97±0.32 p<0.001). PCr/ATP ratios did not differ between Sarc+ and Sarc- HCM even after adjustment for confounders including age, hypertrophy and fibrosis burden (Sarc+ 1.64 [1.50-1.78] vs Sarc- 1.64 [1.52-1.77], p=0.993). PCr/ATP ratio showed no correlation with maximum wall thickness (p=0.257), left ventricular ejection fraction (p=0.727) or myocardial perfusion reserve (p=0.851), but did inversely correlate with global longitudinal strain (r=-0.3, p=0.025). Reduced PCr/ATP was associated with presence of fibrosis (LGE+ 1.58±0.35 vs LGE- 1.79±0.37 p=0.025) and with NSVT, independent of age or fibrosis burden (NSVT+ 1.54 [1.40-1.67] vs NSVT- 1.73 [1.62-1.86], p=0.046). Conclusion Myocardial energetics are similarly impaired in Sarc+ and Sarc- HCM, and are independently associated with impaired contractility, greater fibrosis severity and heightened arrhythmic risk. Our findings provide novel mechanistic insights into the potentially favourable response of HCM patients to energy-sparing myosin modulator therapies irrespective of genotype and highlight the potential for cardiac energetics to serve as a marker of arrhythmic risk.

Impact of obesity and early recurrence of atrial fibrillation on very late recurrence following cryoballoon pulmonary vein isolation

Abstract Background Obesity and early recurrence of atrial fibrillation (ERAF) post cryoballoon (CB) pulmonary vein isolation (PVI) both portend a lower 1-year success rate of ablation. Even after an initial successful ablation, about 1/3 of patients develop a very late recurrence (VLR) of AF, defined as the first AF recurrence more than a year after ablation (excluding an initial 90 day blanking period [BP]). The impact of obesity and ERAF on VLR is still unknown. Purpose To evaluate the impact of obesity and ERAF on VLR following CB PVI. Methods We enrolled consecutive patients with symptomatic AF who underwent CB PVI and had an implantable loop recorder for long-term ECG monitoring. We identified patients who had no AF recurrence (outside the BP) in the first-year post ablation. ERAF was defined as any episode of AF recorded in the first 90 days post ablation. Patients were grouped as either obese (BMI ≥ 30 kg/m2) or non-obese (BMI <30 kg/ m2). AF recurrences after 1-year post-ablation were ascertained using the loop recorder. Results From the initial cohort of 210 patients, 109 (52%) patients (64 ± 10 years; 75 [68%] male; 64 [59%] PAF; CHA2DS2-VASc 2.3 ± 1.4, 38 [35%] with obesity and 41 [38%] had ERAF) were AF-free during the first year. During a follow-up of 961 ± 196 days, 51 (47%) patients had VLR. Non-obese patients without ERAF had the best outcome (Figure). In multivariate analysis, obesity and ERAF were the only significant predictors of VLR (Table). As compared to non-obese patients without ERAF, obese patients with ERAF had a 4-fold greater likelihood of VLR. Conclusions About 50% of patients have no AF recurrence in the first year after CB PVI. Non-obese patients have the best outcome regardless of ERAF occurrence. On the other hand, obese patients with ERAF almost always have VLR.

Digital devices for heart rhythm monitoring in atrial fibrillation patients scheduled for elective electrical cardioversion. Kardiover study

Abstract Introduction the management of patients with recent-onset atrial fibrillation (AF) is to achieve sinus rhythm (SR) by electrical or pharmacological cardioversion (CV). However, frequently SR is spontaneously restored, making scheduled admission and/or transesophageal echocardiogram (TEE) unnecessary and therefore causing misutilization of healthcare resources. Emerging medical technology has allowed for accurate heart rhythm monitoring. Objective to evaluate the diagnostic ability of a smart device ECG monitor to detect spontaneous conversion to SR in AF patients, preventing unnecessary admission and providing an earlier management. Methods A prospective multicenter study (Kardiover study) was designed including patients with paroxysmal, persistent or first diagnosed AF scheduled for elective electrical CV in cardiology departments of 7 hospitals in Spain. Patients were asked to submit ECG recordings to a central Corelab daily, twice a day and whenever they present symptoms, until CV (spontaneous or scheduled) and a week afterwards. Whenever a spontaneous conversion to SR was detected, investigators were contacted to confirm SR and abort admission, likewise when AF recurrence after CV was detected. Patients’ satisfaction was evaluated using a test for perceived utility and value, convenience, and accessibility. Results A total of 74 patients were enrolled (age 62 ± 10 years). Twenty-two patients (30%) showed spontaneous conversion to SR correctly detected by the devices. 86% of the spontaneous CV occurred during the first week. Among 52 patients admitted for CV, 45 (88%) were discharged in SR. During follow up after conversion to SR (spontaneous or electrical), recurrences of AF occurred in 24 patients (34%). At the end of the follow-up 51 patients (69%) remained in SR. Due to the early detection of spontaneous conversion to SR, a total of 22 admissions and 16 TEE were prevented and these resources used for other patients. Patients’ adherence to the protocol in regard to ECG recording transmissions was high, the CoreLab received 93% of the expected transmissions. Patient’s overall satisfaction was also high with a punctuation of 9.1 over 10 in the feedback test. Conclusion Digital devices for heart rhythm monitoring can optimize the management of AF patients scheduled for CV, preventing unnecessary admissions and providing a more rational use of healthcare resources.Baseline characteristicsStudy design and results

Weight change does not impact long-term outcomes following cryoballoon pulmonary vein isolation

Abstract Background Weight loss has been suggested to reduce frequency and burden of atrial fibrillation (AF) in overweight patients (pts). However, there are limited data on weight loss impact on outcomes in pts with AF who have undergone pulmonary vein isolation (PVI). Purpose To understand the impact of weight change on long-term outcomes, as assessed by freedom from recurrent AF in pts undergoing cryoballoon (CB) PVI. Methods We enrolled consecutive pts with AF who underwent CB PVI; all had implantable loop recorders (ILR) for long-term ECG monitoring. The cohort was divided into 4 groups based on weight change 1-year post ablation: (1) optimal weight loss (OWL) – weight decrease ≥ 10%; (2) minimal weight loss (MWL) - weight loss (WL) 3-9% weight decrease; (3) no weight change (NWC) - weight change < 3%, (4) weight gain (WG) ≥ 3% weight increase. We assessed for AF recurrence after excluding a 3-month post-ablation blanking period. Results Out of a total of 322 pts who underwent ablation, 241 (75%) pts (69 ± 10 years; 159 (66%) male; 133 (55%) PAF; CHA2DS2-VASc 2.7 ± 1.5; BMI 30 ± 5) had weight information available at ablation and last follow-up. All were off antiarrhythmics by 1 year. There were no differences in the 4 cohorts with respect to baseline characteristics. During the first year, about ¼ of pts were able to lose ≥ 3% of weight but only 8 pts (3%) were able to lose ≥ 10%. AF recurred in 153 (63%); they were older, more likely to have persistent AF (PeAF), and a higher CHA2DS2-VASc score. However, weight change did not impact outcome (Figure). In a multivariate Cox Regression hazards analysis, PAF vs. PeAF at ablation was the only factor associated with any recurrence at follow-up (Figure). Conclusions Post CB PVI only about ¼ of pts are able to lose weight. Weight changes in the first-year post ablation in obese pts did not alter outcomes with respect to likelihood of recurrent AF. These data should be taken into account when considering catheter ablation.

Validation of diagnostic wearable ECG data from high-risk patients and integration into the atrial fibrillation catheter ablation pathway

Abstract Background Wearables like the Apple Watch (AW) offer non-invasive, long-term monitoring and patient-led, single-lead ECG recordings. Although validated for Atrial Fibrillation (AF) detection in the general population, the accuracy and clinical utility of the single-lead ECG recording feature for the diagnosis of AF has not been evaluated in patients at high risk of atrial arrhythmias.(1) An evaluation of the accuracy of the Wearable-derived labels is important to determine the feasibility of integrating AW-based remote monitoring into clinical pathways. Objective To evaluate the accuracy and data burden from AW-based, patient-led ECG monitoring in patients undergoing AF catheter ablation. Methods Patients referred for first-time AF catheter ablation to the Study Institution between January 2022 and March 2023 were invited to enrol in the AF Follow-up with Apple Watch (AFFU-AW) Trial. Patients randomised to the active arm of the study received 12 months of post-ablation follow-up using a loaned Apple Watch. Participants underwent an education session and were asked to perform daily ECGs; sending through any labelled as AF, inconclusive, or in the context of symptoms. The accuracy of the automated ECG labelling was determined against blinded, independent labelling by two experienced Electrophysiologists. Results 1093 remote transmissions were emailed in for evaluation from 52 patients to the Study team. This was a median of 6 [2, 17] per patient and a receiver burden of 2 [1, 4] ECGs per day. 475 were categorised by the AW as AF with a sensitivity of 0.71 and specificity of 0.96 compared to expert labelling. 342 (31%) were not categorised by the wearable, with an ‘inconclusive’ interpretation (161 [47%]) or ‘high heart rate’ (108 [32%]) as the most cited reasons. 178 (55%) of the uncategorised ECGs were subsequently overread as AF. Accompanying symptoms were reported with 324 (30%) ECGs, most commonly palpitations. Conclusion This is the first reported evaluation of the AF diagnostic feature based on AW ECG recordings as part of a remote patient rhythm surveillance pathway after catheter ablation. The high positive predictive value of ‘Sinus Rhythm’ and ‘AF’ labels and the high specificity of the ‘AF’ label are comparable to diagnostic algorithms in implantable loop recorders.(2) The source code to automate data curation and structured databasing of wearable ECGs has been made available for care providers to integrate the service into device monitoring workflows.(3)

Impact of dapagliflozin on supraventricular and ventricular arrhythmias, assessed by Holter ECG, in patients with heart failure with reduced ejection fraction

Abstract Background & Introduction Dapagliflozin has significantly reduced morbidity & mortality in patients with heart failure with reduced ejection fraction (HFrEF) (1). Some studies reported supraventricular & ventricular arrhythmia suppression, but Holter ECG was underused, hindering precise assessment of arrhythmia burden. Purpose We aim to assess the impact of dapagliflozin on reduction of arrhythmia in HFrEF at 1 year follow-up (FU) by Holter ECG. Methods This is a single center, prospective study. We have screened 219 HFrEF patients, but only 156 patients were enrolled with LVEF <40% in sinus rhythm from December 2021 to July 2023. All patients had dapagliflozin 10 mg once/day tablet with the standard HF therapy. Clinical evaluation, NYHA evaluation, 6-minute walking test (6MWT), echocardiogram, 24-hours Holter ECG and laboratory work-up were done at baseline, and FU at 6 months and 12 months. Results Males constituted 61.5% of study population; mean± SD participants’ age was 56.8 ± 8.6 years. The most common comorbidities were: ischemic etiology (63.3%), dilated cardiomyopathy (28.1%), hypertension (27.3%), smokers (14.7%), and type II diabetes (31.4%). LVEF was ≤ 35% in 85.9% of patients. We have reported (7.69%) deaths during 1-year FU, and 4 patients (2.56%) didn't complete 1-year FU. Main clinical and echocardiographic findings (baseline vs. 1-year FU): NYHA FC III& ambulant IV dropped from (42.9 to 32.9%), P value<0.05. Distance walked in 6MWT improved from 191.52 ± 75.37 to 219.35 ± 71.51 mean± SD meters, P value<0.05. E/e improved (9.4 to 8.3 cm/s, P value <0.01), LVEF improved (31.3 to 36.4%, P value<0.05). HF emergency: [HF visits dropped (23.7 to 19.2%) and HF hospitalization dropped (11.1 to 7.8%)], P value<0.05. Holter ECG (baseline vs. 1-year FU): Supraventricular Arrhythmia: [Paroxysmal AF reduced (56.2 to 47.6%), frequent PACs (≥ 10%) dropped (3.8 to 1.4%) & Intermittent 1st degree heart block dropped (12.5 to 7.3%)] P value <0.01. Ventricular Arrhythmia: [PVCs >5%-<10% dropped (16% to 9.3%), Frequent PVCs >10% dropped (3.2 to 1.4%), and NSVT dropped (7.8 to 3.1%)], P value <0.01. Stepwise logistic regression multivariable model aiming to predict the occurrence of ventricular and supraventricular arrhythmias has indicated a direct linear correlation with male gender, smoking, body mass index, left atrial volume, and a history of myocardial infarction. Conversely, there is an inverse relationship with systolic blood pressure, 6MWT distance, LVEF, and the administration of dapagliflozin (OR 0.72 [0.61 - 1.07], P value <0.01) concerning the likelihood of supraventricular and ventricular arrhythmias. Conclusions Dapagliflozin has demonstrated significant improvement in functional and echocardiographic parameters in HFrEF patients. Furthermore, it has effectively decreased the incidence of supraventricular and ventricular arrhythmias, identified through 24-hour Holter ECG monitoring during 1-year follow-up.

Validation of chest-belt ECG evaluation using artificial intelligence

Abstract Background Simple, cheap wearables for long-term ECG monitoring with automatic analysis of all measurements using a bespoke artificial intelligence (AI) are scarce. Annotated single-lead ECG data from a chest-belt are missing. Methods We have developed a complex software environment to acquire raw ECG data from the Polar H10 chest-belt, and a bespoke, original AI to detect artifacts, QRS complexes and the presence of atrial fibrillation (AF) from chest-belt recordings. Original manually annotated ECG recordings from real patients from cardiology departments using the chest-belt and a public MIT-BIH database as reference were used for validation. Results QRS determination by AI (version Q4/23) in evaluating MIT-BIH database of ECG samples had a 97.67 % sensitivity and a 97.73 % positive predictive value. AF in MIT-BIH database was detected by AI with 90.31 % sensitivity and 92.09 % positive predictive value. To assess AI accuracy in ECG from a chest-belt, 150 consecutive measurements using Polar H10 chest-belt (215 hours of ECG recordings in total) from individual patients were included in the analysis. Patients were not limited in any physical activity during measurements. 7.15 % of the length of all recordings (15.4 hours) was assessed as noise by AI and excluded from the analysis. AF lasting longer than 30 seconds was present in 14 of 150 (9.3 %) manually evaluated recordings. QRS determination by AI in evaluating manually annotated chest-belt data had 99.76 % sensitivity and 99.74 % positive predictive value. AF in manually annotated chest-belt data was detected by AI with 92.86 % sensitivity and 100 % positive predictive value. Conclusion A chest-belt can be used to reliably detect QRS complexes and the presence of atrial fibrillation with high accuracy when using a bespoke artificial intelligence for the evaluation. Commonly available devices capable of long ECG measurements could be used for patient-empowered screening for important arrhythmias.Atrial fibrillation on chest-belt ECG

Effects of baroreceptor reflex modification on efficacy of ablation for atrial fibrillation

Abstract Background The autonomic nervous system (ANS) plays a significant role in atrial fibrillation (AF). Catheter ablation (CA) is a well-established treatment method for AF and significantly affects ANS, including baroreceptors (BR) function. However, little is known about the changes in the BR function caused by radiofrequency (RF) or cryo-energy (CB) influence the efficacy of AF ablation. Purpose To assess one-year efficacy of CA of AF in relation to BR function modification and type of ablation energy used. Methods The study group consisted of 78 patients (25 females, mean age 58±9 years) with paroxysmal AF and first CA (39 patients (RF group) and 39 (CB group)). The BR function was assessed non-invasively using tilt testing and three parameters: event count (BREC) depicting overall BR activity, slope mean depicting BR sensitivity (BRS) and BR effectiveness index (BEI). The efficacy of CA was assessed at 3, 6, and 12 months after CA using 24-hour Holter ECG recordings and dedicated scale (University of Toronto Atrial Fibrillation Severity Scale (AFSS)). Results After CA, BR function decreased in the whole group (mean BREC 12.0±3.0-22.0 vs 6.0±3.0-18.0, p=0.004; mean BRS 4.8±3.6-6.8 vs 4.0±3.0-5.8, p=0.014; mean BEI 18.7±8.3-27.4 vs 12.0±5.1-21.0, p=0.009). BREC was significantly more decreased in the CB vs RF (mean 12.0±3.0-22.0 vs 6.0±3.0-18.0, p=0.004). Similar trend was noted for BRS and BEI. On repeated Holter ECG monitorings efficacy of CB and RF was similar (89.7% vs 82.9% p=0.502, 89.7 vs 85.7%; p=0.727 and 84.6 vs 80%; p=0.602, respectively). According to AFSS, the AF symptoms were significantly reduced in both groups (CB baseline vs 3, 6 a and 12 months, respectively (median): 6.0 (IQR 2.0 – 13.0) vs 2.5 (IQR 1.0 – 4.0), p<0.001; 6.0 (IQR 2.0 – 13.0) vs 1.5 (IQR 0.0 – 4.0), p<0.001; 6.0 (IQR 2.0 – 13.0) vs 1.5 (IQR 0.0 – 4.0), p=0.002; RF baseline vs 3, 6 and 12 months, respectively (median): 10.5 (IQR 5.0 – 14.0) vs 7.0 (IQR 1.0 – 12.0), p=0.173; 10.5 (IQR 5.0 – 14.0) vs: 6.0 (IQR 2.0 – 12.0), p=0.015; 10.5 (IQR 5.0 – 14.0) vs 6.5 (IQR 2.0 – 12.0), p=0.005). After the adjustment for baseline there was no significant differencies between both groups (Table). Conclusions CA significantly affected BR function. These changes were more pronounced following CB than RF CA. However, the efficacy of RF and CB was similar.

Premature ventricular contraction burden measured by an insertable cardiac monitor and the incidence of ventricular tachycardia and fibrillation

Abstract Background Insertable cardiac monitors (ICM) have the capability to continuously monitor premature ventricular contraction (PVC) burden over time [1] as well as detect ventricular tachycardia and fibrillation (VT/VF). Objective We investigated the association of PVC burden with incidence of VT/VF in a large real-world cohort of patients implanted with ICMs. Methods Patients implanted with an ICM for various reasons for monitoring and PVC detection turned on were included from the ICM manufacturer's de-identified data warehouse. Patients were included if they had at least 90 days of PVC burden follow-up. Tachycardia episodes that were detected by the ICM were first classified as VT/VF, SVT, or oversensing using an artificial intelligence (AI) model that was pre-trained using over 60,000 manually adjudicated ICM detected tachycardia episodes. If the AI model output probability for VT/VF was greater than 0.2, then those episodes were manually adjudicated for incidence of non-induced spontaneous VT/VF. The PVC burden trends recorded by the device were divided into 4 mutually exclusive patient groups: (1) 0% PVC burden on all days, (2) 1-4% PVC burden on ≥1 day, (3) 5-9% PVC burden on ≥1 day, and (4) >10% PVC on ≥1 day. The incidence rate of spontaneous VT/VF was compared between the PVC burden patient groups using a Generalized Estimating Equations model with negative binomial distribution. Time to first spontaneous VT/VF occurrence after the first day of occurrence of PVC burden for the respective PVC burden groups were estimated using Kaplan-Meier analysis and the groups were compared using the Cox proportional hazards model. Results A total of 5,521 patients were included in the analysis. Patients had an average age of 69±15 years and 49.8% being males. There was a total of 33,393 tachycardia episodes from 2,641 patients that were detected by the ICM. After AI model probability-based adjudications, 691 spontaneous VT/VF episodes were identified from 277 patients. Patients with ≥1 day of PVC burden of 1-4%, 5-9%, and ≥10% were associated with 2.9, 7.3, and 7.8 times increased incidence rate of VT/VF episodes during follow-up period relative to patients with 0% PVC burden on all days of follow-up (Figure A). Kaplan Meier curves for incidence of first spontaneous VT/VF episode for the four groups following occurrence of the first day of qualifying PVC burden for the respective groups are shown in figure B. Patients with a day of PVC burden ≥10% were 3.5 times more likely to develop VT/VF in the future compared to patients with 0% PVC burden on all days. Conclusion Days with high PVC burden, as detected by an ICM with continuous PVC detection capability, were associated with increased risk of VT/VF events in a group of real-world patients implanted with ICMs. PVC burden measured by ICMs may be a risk stratification tool for further investigation to prevent sudden cardiac arrest.

Cardiological monitoring during BTK inhibitor, ICI, and RAF/MEK inhibitor therapy: the single-center prospective registry for cardiovascular events under new cancer therapies (RECENT)

Abstract Background The advent of novel targeted cancer therapies have revolutionized cancer treatment. However, concerns about their impact on cardiovascular health persist and current guidelines recommend cardiac monitoring. Yet, prospective data on incidence rates of cardiovascular events are lacking. The Registry for Cardiovascular Events under new cancer Therapies (RECENT) aims to systematically assess clinical as well as subclinical cardiovascular incidents in patients undergoing these novel therapies to identify baseline risk factors and derive individualized monitoring strategies. Methods This ongoing single-center prospective registry enrolls cancer patients receiving BTK inhibitors, ICI, or RAF/MEK inhibitors. Baseline cardiovascular assessment, risk stratification according to HFA-ICOS risk score, and follow up visits for 12 months at three-monthly intervals (including ECG, biomarkers and echocardiography) during treatment are conducted. Treatment-related events, in particular hypertension, arrhythmias, cancer therapy-related cardiac dysfunction (CTRCD), and (peri-) myocarditis, as defined according to current guideline recommendations, are recorded. Results We report data of the first 85 patients (60.9 ± 14.7 years, 52.9% male) included in this ongoing registry. Of those, 17/85 patients received treatment with BTK inhibitors (20%), 45/85 with ICI (53%) and 23/85 with RAF/MEK inhibitors (27%). Most common treatment indication were dermatological (39/85, 45.9%), hematologic (17/85, 20%), urological (13/85, 15.3%) and head and neck (11/85, 12.9%) cancers. Before treatment, the majority of patients were stratified as low-risk (31/85) or moderate-risk (32/85), and 22/85 (25.9%) as high-risk. 7/85 (8.2%) patients were newly diagnosed with cardiovascular disease at baseline visit, resulting in a change in risk category and subsequent initiation of cardiovascular treatment. This includes 3 patients who had been initially categorized as low-risk and would not have been referred for further cardiac workup due to current guideline recommendations. The six months follow up visit has been completed in 44/85 patients. Among these, 1/20 patients (5%) with ICI developed a perimyocarditis and 2/11 patients (18.2%) with BTK inhibitors developed atrial fibrillation. 1/13 patients (7.7%) with RAF/MEK inhibitor therapy, classified as low-risk at baseline, developed asymptomatic CTRCD, which resolved after initiation of cardioprotective drug therapy. Conclusion This interim analysis of the RECENT registry indicates benefit of a structured baseline cardiac assessment prior to cancer treatment in all patients, irrespective of the initial risk stratification. Contrary to current guidelines, which recommend routine echocardiographic monitoring in patients receiving RAF/MEK inhibitors only in high-risk patients, the current data advocate for extending this also to low-risk patients to detect subclinical deterioration of the cardiovascular status.

Survival and predictors of mortality in patients with heart failure in the cardiology department of the Center Hospitalier Basse Terre in Guadeloupe: historical cohort study

BackgroundDespite the progress made in recent years in the treatment of Acute Heart Failure (AHF), its prognosis remains poor in the developing country. The objective of this study is to analyze the survival and predictors of mortality of patients with acute heart failure in the cardiology department of the Basse Terre Hospital Center in Guadeloupe.Methodsthis was a historical cohort study carried out over a period from June 2021 to June 2022, targeting all acute heart failure patients undergoing cardiac monitoring in the cardiology department of the Basse Terre Hospital Center in Guadeloupe. Sociodemographic, clinical, biological characteristics and outcome (recovery or death) were studied. Survival was described using the Kaplan Meier method α = 5%.Resultsthis study involved 242 acute heart failure patients whose median age was 75 years and the majority were male (sex ratio 2 M/1F). Among these patients, 14.9% died, the most common cause of death was cardiogenic shock (52.8%). After adjustment, tobacco consumption (aHR: 2.90; 95% CI: 1.36–8.09), Chronic Kidney Disease (aHR: 2.52; 95% CI: 1.22–5.20), infection (aHR: 2.14; 95CI %: 1.99–4.58), hyponatremia (aHR: 1.90; 95% CI: 1.10–2.86), mitral regurgitation (aHR: 3.04; 95% CI: 1.98–9.47) and N-terminal pro Brain Natriuretic Peptide > 10000ng/ml (aHR: 2.57; 95% CI: 1.21–5.49) were independently associated with the risk of death in heart failure patients.ConclusionAcute heart failure leads to high mortality, mainly due to cardiogenic shock and factors of multiple organ failure.