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.

Self-Reported Mobile Health-Based Risk Factor and CHA2DS2-VASc-Score Assessment in Patients With Atrial Fibrillation: TeleCheck-AF Results.

INTRODUCTION: The TeleCheck-AF approach is an on-demand mobile health (mHealth) infrastructure incorporating mobile app-based heart rate and rhythm monitoring through teleconsultation. We evaluated feasibility and accuracy of self-reported mHealth-based AF risk factors and CHA2DS2-VASc-score in atrial fibrillation (AF) patients managed within this approach. MATERIALS AND METHODS: Consecutive patients from eight international TeleCheck-AF centers were asked to complete an app-based 10-item questionnaire related to risk factors, associated conditions and CHA2DS2-VASc-score components. Patient's medical history was retrieved from electronic health records (EHR). RESULTS: Among 994 patients, 954 (96%) patients (38% female, median age 65 years) completed the questionnaire and were included in this analysis. The accuracy of self-reported assessment was highest for pacemaker and anticoagulation treatment and lowest for heart failure and arrhythmias. Patients who knew that AF increases the stroke risk, more often had a 100% or ≥80% correlation between EHR- and app-based results compared to those who did not know (27 vs. 14% or 84 vs. 77%, P = 0.001). Thromboembolic events were more often reported in app (vs. EHR) in all countries, whereas higher self-reported hypertension and anticoagulant treatment were observed in Germany and heart failure in the Netherlands. If the app-based questionnaire alone was used for clinical decision-making on anticoagulation initiation, 26% of patients would have been undertreated and 6.1%-overtreated. CONCLUSION: Self-reported mHealth-based assessment of AF risk factors is feasible. It shows high accuracy of pacemaker and anticoagulation treatment, nevertheless, displays limited accuracy for some of the CHA2DS2-VASc-score components. Direct health care professional assessment of risk factors remains indispensable to ensure high quality clinical-decision making.

On-demand mobile health infrastructures to allow comprehensive remote atrial fibrillation and risk factor management through teleconsultation.

BACKGROUND: Although novel teleconsultation solutions can deliver remote situations that are relatively similar to face-to-face interaction, remote assessment of heart rate and rhythm as well as risk factors remains challenging in patients with atrial fibrillation (AF). HYPOTHESIS: Mobile health (mHealth) solutions can support remote AF management. METHODS: Herein, we discuss available mHealth tools and strategies on how to incorporate the remote assessment of heart rate, rhythm and risk factors to allow comprehensive AF management through teleconsultation. RESULTS: Particularly, in the light of the coronavirus disease 2019 (COVID-19) pandemic, there is decreased capacity to see patients in the outpatient clinic and mHealth has become an important component of many AF outpatient clinics. Several validated mHealth solutions are available for remote heart rate and rhythm monitoring as well as for risk factor assessment. mHealth technologies can be used for (semi-)continuous longitudinal monitoring or for short-term on-demand monitoring, dependent on the respective requirements and clinical scenarios. As a possible solution to improve remote AF care through teleconsultation, we introduce the on-demand TeleCheck-AF mHealth approach that allows remote app-based assessment of heart rate and rhythm around teleconsultations, which has been developed and implemented during the COVID-19 pandemic in Europe. CONCLUSION: Large scale international mHealth projects, such as TeleCheck-AF, will provide insight into the additional value and potential limitations of mHealth strategies to remotely manage AF patients. Such mHealth infrastructures may be well suited within an integrated AF-clinic, which may require redesign of practice and reform of health care systems.

Evaluation of different magnetic resonance imaging techniques for the assessment of active left atrial emptying.

OBJECTIVES: There is currently no agreement on the best method of assessing active left atrial (LA) emptying. This study evaluated the relative merits of cine- and velocity encoded (VENC) magnetic resonance imaging (MRI) for the assessment of active LA emptying. METHODS: Total LA emptying volume (TLAEV) and active LA stroke volume (ALASV) were assessed in 107 consecutive patients using cine-MRI and transmitral flow measurements by VENC-MRI. The fraction of active LA emptying (ALAEF) was calculated as the ratio of ALASV to TLAEV. LA and left ventricular (LV) output were calculated by multiplying TLAEV and LV stroke volume by heart rate, respectively. RESULTS: Intra- and inter-observer variances were significantly larger for cine-MRI than for VENC-MRI measurements of ALASV (24.7 mL(2) vs. 3.7 mL(2) and 57.7 mL(2) vs. 4.2 mL(2); P < 0.0001). Biplane cine-MRI underestimated TLAEV (mean difference -57 ± 32 %; P < 0.0001) and ALASV (mean difference -24 ± 51 %; P < 0.0001) but overestimated ALAEF (mean difference 31 ± 54 %, P < 0.0001) compared with VENC-MRI. There was significantly better agreement between LV output and LA output measured by VENC-MRI compared with LA output measured by cine-MRI (mean difference 0.30 ± 1.12 L/min vs. -2.05 ± 1.44 L/min; P < 0.0001). CONCLUSION: VENC-MRI is the more appropriate method of assessing active LA emptying and its use should be favoured.

Propofol sedation administered by cardiologists without assisted ventilation for long cardiac interventions: an assessment of 1000 consecutive patients undergoing atrial fibrillation ablation.

AIMS: Patients can expect a cure from atrial fibrillation (AF) with ablation. Procedural safety and success depend on patient comfort, compliance, and immobility. This is difficult to achieve with benzodiazepine and opiate boluses that are the mainstay of current practice. We sought to determine the safety and efficacy of propofol infusion sedation administered to patients without assisted ventilation for AF ablation. METHODS AND RESULTS: Procedural data from 1000 consecutive patients undergoing AF ablation were analysed. Sedation with 2% propofol was used in all procedures without assisted ventilation and was administered, monitored, and controlled by electrophysiologists. Primary outcome measures were adverse sedative affects including (i) respiratory depression (SpO(2)< 90% for >20 s) and (ii) persistent hypotension [systolic blood pressure (SBP)<90 mmHg at minimum sedation level]. Secondary endpoints included full recovery within 60 min and procedural complications. Of 1000 ablations, 506 ablations were performed for persistent and 494 for paroxysmal AF. Average patient age was 60.1 ± 11.3 years (72.3% male). Propofol was commenced in all patients at a mean infusion rate of 18.5 ± 4.8 mL/h with a mean baseline SBP of 140.3 ± 19.9 mmHg. Mean procedure time was 148.7 ± 57.7 min. Adverse sedative effects necessitating cessation of propofol and switch to midazolam bolus sedation occurred in 15.6% of patients (13.6% due to persistent hypotension, 1.9% due to respiratory depression, and 0.1% due to hypersalivation). Patients who had persistent hypotension were older (62.9 ± 11.2 vs. 60.0 ± 11.4 years, P= 0.011) and more likely to be female (39.5 vs. 23.7%, P< 0.001) than those who tolerated propofol. Patient age correlated to maximum blood pressure drop with propofol (R(2)= 0.101, P< 0.001) and inversely correlated to mean propofol infusion rate (R(2)= 0.066, P< 0.001). No procedures were abandoned due to adverse effects of sedation. All patients recovered within 60 min. Serious procedural complications, unrelated to sedation, occurred in 0.5%, all of whom had pericardial tamponade successfully treated with percutaneous pericardiocentesis. CONCLUSIONS: Sedation with 2% propofol infusion administered by cardiologists without assisted ventilation is safe, effective, and practical for use in AF ablation without serious or residual complications. In this setting, persistent hypotension is the most common acute adverse effect requiring cessation of propofol in ∼14%.