Incidence, implications, and management of sense-B-noise failure in subcutaneous cardioverter-defibrillator patients: insights from a large multicentre registry.

AIMS: Subcutaneous implantable cardioverter-defibrillators (S-ICDs) offer potentially distinct advantages over transvenous defibrillator systems. Recent randomized trials showed significantly lower lead failure rates than transvenous ICD. Still, S-ICDs remain associated with the risk of inappropriate shocks (IAS). While previous studies have reported varying causes of IAS, this study explores a rare cause of IAS, referred to as 'sense-B-noise.' It was recently described in case series, but its incidence has not been studied in a large cohort of S-ICD patients. METHODS AND RESULTS: We retrospectively reviewed data from patients implanted with S-ICD models 1010, A209, and A219 between October 2009 and July 2023 across nine centres in Europe and the USA. The analysis concentrated on determining the incidence and understanding the implications of sense-B-noise events. Sense-B-noise represents a rare manifestation of distinct electrogram abnormalities within the primary and alternate sensing vectors. Data were collected from medical records, device telemetry, and manufacturer reports for investigation. This registry is registered on clinicaltrials.gov (NCT05713708). Subcutaneous implantable cardioverter-defibrillator devices of the 1158 patients were analysed. The median follow-up time for all patients was 46 (IQR 23-64) months. In 107 patients (9.2%) ≥1 IAS was observed during follow-up. Sense-B-noise failure was diagnosed in six (0.5 and 5.6% of all IAS) patients, in all patients, the diagnosis was made after an IAS episode. Median lead dwell time in the affected patients was 23 (2-70) months. To resolve the sense-B-noise defect, in three patients reprogramming to the secondary vector was undertaken, and two patients underwent system removal with subsequent S-ICD reimplantation due to low amplitude in the secondary vector. In one patient, the secondary vector was initially programmed, and subsequently, an S-ICD system exchange was performed due to T-wave-oversensing IAS episodes. CONCLUSION: This multicentre analysis' findings shed light on a rare but clinically highly significant adverse event in S-ICD therapy. To our knowledge, we provide the first systematic multicentre analysis investigating the incidence of sense-B-noise. Due to being difficult to diagnose and limited options for resolution, management of sense-B-noise is challenging. Complete system exchange may be the only option for some patients. Educating healthcare providers involved in S-ICD patient care is crucial for ensuring accurate diagnosis and effective management of sense-B-noise issues.

Occurrence of Premature Battery Depletion in a Large Multicenter Registry of Subcutaneous Cardioverter-Defibrillator Patients.

AIMS AND BACKGROUND: Subcutaneous implantable cardioverter-defibrillators (S-ICD) have become established in preventing sudden cardiac death, with some advantages over transvenous defibrillator systems, including a lower incidence of lead failures. Despite technological advancements, S-ICD carriers may suffer from significant complications, such as premature battery depletion (PBD) which led to an advisory for nearly 40,000 patients. This multicenter study evaluated the incidence of PBD in a large set of S-ICD patients. METHODS: Data from patients implanted with S-ICD models A209 and A219 between October 2012 and July 2023 across 9 centers in Europe and the USA was reviewed. Incidence and implications of PBD, defined as clinically observed sudden drop in battery longevity were analyzed and compared to PBD with the definition of battery depletion within 60 months. Prospectively collected clinical data was obtained retrospectively from medical records, device telemetry, and manufacturer reports. This registry is listed on clinicaltrials.gov (NCT05713708). RESULTS: Of the 1,112 S-ICD devices analyzed, 547 (49.2%) were equipped with a potentially affected capacitor linked to PBD occurrence, currently under FDA advisory. The median follow-up time for all patients was 46 (IQR 24-63) months. Clinically suspected PBD was observed in 159 (29.1%) of cases, with a median time to generator removal or replacement of 65 (IQR 55-72) months, indicative of significant deviations from expected battery lifespan. Manufacturer confirmation of PBD was made in 91.7% of devices returned for analysis. No cases of PBD were observed in devices that were not under advisory. CONCLUSION: This manufacturer-independent analysis highlights a notable incidence of PBD in patients equipped with S-ICD models under advisory and the rate of PBD in this study corresponds to the rate currently estimated by the manufacturer. To the best of our knowledge this provides the largest contemporary peer-reviewed study cohort investigating the actual incidence of PBD in S-ICD patients. These findings emphasize the importance of post-market registries in collaboration between clinicians and the manufacturer to optimize safety and efficacy in S-ICD treatment.

Catheter-based pulmonary vein isolation fails to prevent transient atrial arrhythmogenic changes related to acute obstructive respiratory events in a porcine model.

AIMS: Pulmonary vein isolation (PVI) is the corner stone of modern rhythm control strategies in patients with atrial fibrillation (AF). Sleep-disordered breathing (SDB) is prevalent in more than 50% of patients undergoing AF ablation, and studies have indicated a greater recurrence rate after PVI in patients with SDB. Herein, we study the effect of catheter-based PVI on AF in a pig model for SDB. METHODS AND RESULTS: In 11 sedated spontaneously breathing pigs, obstructive apnoeas were simulated by 75 s of intermittent negative upper airway pressure (INAP) applied by a negative pressure device connected to the endotracheal tube. Intermittent negative upper airway pressures were performed before and after PVI. AF-inducibility and atrial effective refractory periods (aERPs) were determined before and during INAP by programmed atrial stimulation. Pulmonary vein isolation prolonged the aERP by 48 ± 27 ms in the right atrium (RA) (P < 0.0001) and by 40 ± 34 ms in the left atrium (LA) (P = 0.0004). Following PVI, AF-inducibility dropped from 28 ± 26% to 0% (P = 0.0009). Intermittent negative upper airway pressure was associated with a transient aERP-shortening (ΔaERP) in both atria, which was not prevented by PVI (INAP indued ΔaERP after PVI in the RA: -57 ± 34 ms, P = 0.0002; in the LA: -42 ± 24 ms, P < 0.0001). Intermittent negative upper airway pressure was associated with a transient increase in AF-inducibility (from 28 ± 26% to 69 ± 21%; P = 0.0008), which was not attenuated by PVI [INAP-associated AF-inducibility after PVI: 58 ± 33% (P = 0.5)]. CONCLUSION: Transient atrial arrhythmogenic changes related to acute obstructive respiratory events are not prevented by electrical isolation of the pulmonary veins, which partially explains the increased AF recurrence in patients with SDB after PVI procedures.

Temporal association of ventricular arrhythmias and respiratory events in heart failure patients with central sleep apnoea.

In contrast to obstructive sleep apnoea, the peak of sympathetic tone in central sleep apnoea occurs during the hyperventilation phase. To explore the temporal association of premature ventricular complex (PVC) burden in the context of the apnoea/hypopnoea-hyperpnoea cycle, the duration of apnoea/hypopnoea was defined as 100 %. We assessed the PVC burden throughout the apnoea/hypopnoea-hyperpnoea cycle during the periods of ±150 % in 50 % increments before and after the apnoea/hypopnoea phase. In this subanalysis of 54 SERVE-HF patients, PVC burden was 32 % higher in the late hyperventilation period (50-100 % after apnoea/hypopnoea) compared to the apnoea/hypopnoea phase.

Electrocardiographic markers in patients with type 2 diabetes and the role of diabetes duration.

BACKGROUND: The association between type 2 diabetes and electrocardiographic (ECG) markers are incompletely explored and the dependence on diabetes duration is largely unknown. We aimed to investigate the electrocardiographic (ECG) changes associated with type 2 diabetes over time. METHODS: In this cross-sectional study, we matched people with type 2 diabetes 1:1 on sex, age, and body mass index with people without diabetes from the general population. We regressed ECG markers with the presence of diabetes and the duration of clinical diabetes, respectively, adjusted for sex, age, body mass index, smoking, heart rate, diabetes medication, renal function, hypertension, and myocardial infarction. RESULTS: We matched 988 people with type 2 diabetes (332, 34% females) with as many controls. Heart rate was 8 bpm higher (p < 0.001) in people with vs. without type 2 diabetes, but the difference declined with increasing diabetes duration. For most depolarization markers, the difference between people with and without type 2 diabetes increased progressively with diabetes duration. On average, R-wave amplitude was 6 mm lower in lead V5 (p < 0.001), P-wave duration was 5 ms shorter (p < 0.001) and QRS duration was 3 ms (p = 0.03). Among repolarization markers, T-wave amplitude (measured in V5) was lower in patients with type 2 diabetes (1 mm lower, p < 0.001) and the QRS-T angle was 10 degrees wider (p = 0.002). We observed no association between diabetes duration and repolarization markers. CONCLUSIONS: Type 2 diabetes was independently associated with electrocardiographic depolarization and repolarization changes. Differences in depolarization markers, but not repolarization markers, increased with increasing diabetes duration.

Longer and better lives for patients with atrial fibrillation: the 9th AFNET/EHRA consensus conference.

AIMS: Recent trial data demonstrate beneficial effects of active rhythm management in patients with atrial fibrillation (AF) and support the concept that a low arrhythmia burden is associated with a low risk of AF-related complications. The aim of this document is to summarize the key outcomes of the 9th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). METHODS AND RESULTS: Eighty-three international experts met in Münster for 2 days in September 2023. Key findings are as follows: (i) Active rhythm management should be part of the default initial treatment for all suitable patients with AF. (ii) Patients with device-detected AF have a low burden of AF and a low risk of stroke. Anticoagulation prevents some strokes and also increases major but non-lethal bleeding. (iii) More research is needed to improve stroke risk prediction in patients with AF, especially in those with a low AF burden. Biomolecules, genetics, and imaging can support this. (iv) The presence of AF should trigger systematic workup and comprehensive treatment of concomitant cardiovascular conditions. (v) Machine learning algorithms have been used to improve detection or likely development of AF. Cooperation between clinicians and data scientists is needed to leverage the potential of data science applications for patients with AF. CONCLUSIONS: Patients with AF and a low arrhythmia burden have a lower risk of stroke and other cardiovascular events than those with a high arrhythmia burden. Combining active rhythm control, anticoagulation, rate control, and therapy of concomitant cardiovascular conditions can improve the lives of patients with AF.

Cardiovascular disease and risk in COPD: a state of the art review.

INTRODUCTION: Chronic Obstructive Pulmonary Disease (COPD) and cardiovascular diseases (CVD) commonly co-exist. Outcomes of people living with both conditions are poor in terms of symptom burden, receiving evidence-based treatment and mortality. Increased understanding of the underlying mechanisms may help to identify treatments to relieve this disease burden. This narrative review covers the overlap of COPD and CVD with a focus on clinical presentation, mechanisms, and interventions. Literature up to December 2023 are cited. AREAS COVERED: 1. What is COPD 2. The co-existence of COPD and cardiovascular disease 3. Mechanisms of cardiovascular disease in COPD. 4. Populations with COPD are at risk of CVD 5. Complexity in the co-diagnosis of COPD in those with cardiovascular disease. 6. Therapy for COPD and implications for cardiovascular events and risk. 7. Cardiovascular risk and exacerbations of COPD. 8. Pro-active identification and management of CV risk in COPD. EXPERT OPINION: The prospective identification of co-morbid COPD in CVD patients and of CVD and CV risk in people with COPD is crucial for optimizing clinical outcomes. This includes the identification of novel treatment targets and the design of clinical trials specifically designed to reduce the cardiovascular burden and mortality associated with COPD. Databases searched: Pubmed, 2006-2023.

Clinical Predictors of Device-Detected Atrial Fibrillation During 2.5 Years After Cardiac Surgery: Prospective RACE V Cohort.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a frequent complication after cardiac surgery that is associated with late atrial fibrillation (AF) recurrences (late-POAF) and increased morbidity and long-term mortality. OBJECTIVES: This study sought to determine device-detected POAF incidence and to identify clinical variables associated with POAF, both in patients with and without preoperative AF history. METHODS: A total of 133 consecutive patients undergoing cardiac surgery were prospectively enrolled and continuously monitored with an implantable loop recorder for 2.5 years after surgery. Preoperative transthoracic echocardiography, 12-lead electrocardiogram, blood biomarkers, and clinical data were analyzed to develop prediction models for early- and late-POAF. RESULTS: In patients without preoperative AF history, early-POAF within the first 90 postoperative days occurred in 41 (47.1%) of 87 patients. Late-POAF after the first 90 postoperative days occurred in 22 (25%) of 87 patients, and 20 of these patients also had early-POAF during the first 90 days (20 of 22 [91%]). Increased right atrial minimum volume indexed for body surface area (RAVImin) and early-POAF were independently associated with late-POAF. A prediction model for late-POAF, which included RAVImin >11 mL/m2, age >65 years, and early-POAF, achieved an area under the curve of 0.82 (95% CI: 0.72-0.92). For patients with preoperative AF-history, late-POAF recurrences were frequent (22 of 33 [67%]). Increased RAVImin was independently associated with a higher incidence of late-POAF. CONCLUSIONS: In patients with and without AF history, late-POAF recurrences are frequent, including in patients undergoing surgical AF ablation. In patients with no history of AF, late-POAF might be predicted with excellent accuracy by using a combination of preoperative variables. In patients with a history of AF, signs of advanced AF substrate (eg, increased right atrial volumes) were associated with long-term AF recurrences. [Reappraisal of Atrial Fibrillation: Interaction Between Hypercoagulability, Electrical Remodeling, and Vascular Destabilisation in the Progression of AF; NCT03124576].

[Characterization of atrial fibrillation burden using wearables]. / Charakterisierung der Vorhofflimmerlast mittels Wearables.

The characterization of atrial fibrillation (AF) according to current guidelines categorically refers to the differentiation between paroxysmal, persistent, and permanent AF. A more precise characterization of AF, including the evaluation of AF burden, is playing an increasingly significant role in both scientific research and clinical practice. Digital devices, especially those with the capability of passive (semi-)continuous recording, can contribute to a more accurate quantification of AF burden. Particularly in patients with an already established diagnosis of AF, the evaluation of AF burden can be used to monitor the success of antiarrhythmic therapy including antiarrhythmic drugs or pulmonary vein isolation. However, important questions remain unanswered: In addition to a uniform, evidence-based definition of AF burden, clinically relevant cut-offs for AF burden and resulting therapeutic consequences (e.g., subclinical AF) need to be elaborated. Furthermore, the establishment and evaluation of care structures for assessing and integrating AF burden in clinical care, especially by incorporating data from wearable medical devices, should take place.

The impact of Twitter/X promotion on visibility of research articles: Results of the #TweetTheJournal study.

Aim: Social media (SoMe) are emerging as important tools for research dissemination. Twitter/X promotion has been shown to increase citation rates in well-established journals. We aimed to test the effect of a SoMe promotion strategy on the Mendeley reader counts, the Altmetric Attention Score and the number of citations in an upcoming open-access journal. Methods: The #TweetTheJournal study is a randomized, controlled study. Articles published in seven subsequent issues of the International Journal of Cardiology Heart & Vasculature (April 2021-April 2022) were randomized to a Twitter/X promotion arm (articles were posted four times) and to a control arm (without active posting). Articles with accompanied editorials were excluded. Primary endpoint of the study was Mendeley reader count, secondary endpoints were Altmetric Attention Score and number of citations. Follow-up was one year. Results: SoMe promotion of articles showed no statistically significant difference in Mendeley reader counts or number of citations at one year follow up. SoMe promotion resulted in a statistically significant higher Altmetric Attention Score in the intervention compared to the control group (RR 1.604, 95 % CI 1.024-2.511, p = 0.039). In the overall group, Altmetric Attention Score showed a correlation with Mendeley reader counts (Spearman's ρ = 0.202, p = 0.010) and Mendeley reader counts correlated significantly with number of citations (Spearman's ρ = 0.372, p < 0.001). Conclusion: A dedicated SoMe promotion strategy did not result in statistically significant differences in early impact indicators as the Mendeley reader count in a upcoming journal, but increased the Altmetric Attention Score.

Atrial fibrillation: epidemiology, screening and digital health.

Atrial fibrillation (AF) is highly prevalent with a lifetime risk of about 1 in 3-5 individuals after the age of 45 years. Between 2010 and 2019, the global prevalence of AF has risen markedly from 33.5 million to 59 million individuals living with AF. Early detection of AF and implementation of appropriate treatment could reduce the frequency of complications associated with AF. International AF management guidelines recommend opportunistic and systematic screening for AF, but additional data are needed. Digital approaches and pathways have been proposed for early detection and for the transition to early AF management. Mobile health (mHealth) devices provide an opportunity for digital screening and should be part of novel models of care delivery based on integrated AF care pathways. For a broad implementation of mHealth-based, integrated care for patients with chronic diseases as AF, further high quality evidence is necessary. In this review, we present an overview of the present data on epidemiology, screening techniques, and the contribution of digital health solutions to the integrated management of AF. We also provide a systemic review on current data of digital and integrated AF management.

Inhibition of the acetylcholine-regulated potassium current prevents transient apnea-related atrial arrhythmogenic changes in a porcine model.

BACKGROUND: More than 50% of patients with atrial fibrillation (AF) suffer from sleep disordered breathing (SDB). Obstructive respiratory events contribute to a transient, vagally mediated atrial arrhythmogenic substrate, which is resistant to most available antiarrhythmic drugs. OBJECTIVE: The purpose of this study was to investigate the effect of pharmacologic inhibition of the G-protein-gated acetylcholine-regulated potassium current (IK,ACh) with and without acute autonomic nervous system activation by nicotine in a pig model for obstructive respiratory events. METHODS: In 21 pigs, SDB was simulated by applying an intermittent negative upper airway pressure (INAP). AF inducibility and atrial effective refractory periods (aERPs) were determined before and during INAP by an S1S2 atrial pacing-protocol. Pigs were randomized into 3 groups-group 1: vehicle (n = 4); group 2: XAF-1407 (IK,ACh inhibitor) (n = 7); and group 3: nicotine followed by XAF-1407 (n = 10). RESULTS: In group 1, INAP shortened aERP (ΔaERP -42.6 ms; P = .004) and transiently increased AF inducibility from 0% to 31%. In group 2, XAF-1407 prolonged aERP by 25.2 ms (P = .005) during normal breathing and prevented INAP-induced aERP shortening (ΔaERP -3.6 ms; P = .3) and AF inducibility. In group 3, INAP transiently shortened aERP during nicotine perfusion (ΔaERP -33.6 ms; P = .004) and increased AF inducibility up to 61%, which both were prevented by XAF-1407. CONCLUSION: Simulated obstructive respiratory events transiently shorten aERP and increase AF inducibility, which can be prevented by the IK,ACh-inhibitor XAF-1407. XAF-1407 also prevents these arrhythmogenic changes induced by obstructive respiratory events during nicotine perfusion. Whether IK,ACh channels represent a target for SDB-related AF in humans warrants further study.

Changes in healthcare utilisation during implementation of remote atrial fibrillation management: TeleCheck-AF project.

AIM: To evaluate changes in healthcare utilisation and comprehensive packages of care activities and procedures (referred in the Netherlands to as 'diagnose-behandelcombinatie (DBC) care products) during the implementation of the TeleCheck-AF approach (teleconsultation supported by app-based heart rate/rhythm monitoring) in a Dutch atrial fibrillation (AF) clinic. METHODS AND RESULTS: In the Maastricht University Medical Centre+ AF Clinic, data on healthcare utilisation and DBC care products for patients consulted by both a conventional approach in 2019 and the TeleCheck-AF approach in 2020 were analysed. A patient experience survey was performed. Thirty-seven patients (median age 68 years; 40% women) were analysed. With the conventional approach, 35 face-to-face consultations and 0 teleconsultations were conducted. After the implementation of TeleCheck-AF, the number of face-to-face consultations dropped by 80% (p < 0.001) and teleconsultations increased to 45 (p < 0.001). While 42 electrocardiograms (ECGs) and 25 Holter ECGs or echocardiograms were recorded when using the conventional approach, the number of ECGs decreased by 71% (p < 0.001) and Holter ECGs or echocardiograms by 72% (p < 0.001) with the TeleCheck-AF approach. The emergency department patient presentations showed no statistically significant change (p = 0.33). Overall, 57% of medium-weight DBC care products were changed to light-weight ones during implementation of the TeleCheck-AF approach. Patient satisfaction with the TeleCheck-AF approach was high. CONCLUSION: The implementation of TeleCheck-AF led to a change in healthcare utilisation, a change from medium-weight to light-weight DBC care products and a reduction in patient burden. These results created the basis for a new reimbursement code for the TeleCheck-AF approach in the Netherlands.

Network analysis of the social media activities around the #TeleCheckAF project.

Aims: TeleCheck-AF is a novel remote on-demand mobile health infrastructure around teleconsultations for patients with atrial fibrillation. Social media (SoMe) communication on Twitter contributed to the dissemination of this healthcare innovation by using the hashtag #TeleCheckAF. This study aims to analyse the SoMe network behind #TeleCheckAF and determine the key opinion leaders. Methods and results: Publicly available data on actors and interactions around the hashtag #TeleCheckAF were collected by web scraping from the platform Twitter. With tools based on social network analysis, a social network was created, different communities were identified, and key opinion leaders were determined by their centrality in the network. The SoMe network consisted of 413 086 accounts with 636 502 ties in 22 different communities. A total of 287 accounts that diffused information and/or used the TeleCheck-AF infrastructure were analysed in depth. Those accounts involved users from >15 different countries and multidisciplinary professions. Further, 20 opinion leaders were identified, including four official accounts of societies and associated journals among key opinion leaders. Peaks in #TeleCheckAF tweets were seen after (virtual) conferences and other activities involving national and international cardiology societies. Social network analysis of the TeleCheck-AF Twitter hashtag revealed a wide, multidisciplinary potential reach for the diffusion of a healthcare innovation. Conclusion: Official society SoMe accounts can amplify the dissemination of research findings by featuring abstract presentations during conferences and published manuscripts. This underlines the synergistic effects between traditional and SoMe-based research dissemination strategies for novel healthcare approaches, such as the TeleCheck-AF project.

Adherence to a handheld device-based atrial fibrillation screening protocol is associated with clinical outcomes.

OBJECTIVE: To evaluate adherence and adherence consistency to the handheld ECG device-based screening protocol and their association with adverse cerebral and cardiovascular outcomes in two systematic atrial fibrillation (AF) screening programmes. METHODS: In 2012 (Systematic ECG Screening for Atrial Fibrillation Among 75-Year Old Subjects in the Region of Stockholm and Halland, Sweden (STROKESTOP) study) and 2016 (Stepwise mass screening for atrial fibrillation using N-terminal pro b-type natriuretic peptide (STROKESTOP II) study), half of all 75- and 76-year-old inhabitants of up to two Swedish regions were invited to participate in a systematic AF screening programme. Participants were instructed to perform 30-second measurements twice daily in STROKESTOP and four times daily in STROKESTOP II for 2 weeks. Adherence was defined as the number of measurements performed divided by the number of measurements asked, whereas adherence consistency was defined as the number of days with complete registrations. RESULTS: In total, 6436 participants (55.7% female) from STROKESTOP and 3712 (59.8% female) from STROKESTOP II were included. Median adherence and adherence consistency were 100 (92-100)% and 12 (11-13) days in STROKESTOP and 90 (75-98)% and 8 (3-11) days in STROKESTOP II. Female sex and lower education were factors associated with both optimal adherence and adherence consistency in both studies. In STROKESTOP, low adherence and adherence consistency were associated with higher risk of adverse cerebral and cardiovascular outcomes (HR for composite primary endpoint 1.30 (1.11 to 1.51), p=0.001), including stroke (HR 1.68 (1.22 to 2.32), p=0.001) and dementia (1.67 (1.27 to 2.19), p<0.001). CONCLUSIONS: Adherence to twice daily handheld ECG measurements in STROKESTOP was higher than to four times daily measurements in STROKESTOP II. Female sex and lower educational attainment were associated with ≥100% adherence and adherence consistency. Low adherence and adherence consistency were associated with a higher risk of adverse outcomes.