Smartphone app-based approximation of time spent with atrial fibrillation and symptoms in patients after catheter ablation: data from the TeleCheck-AF project.

AIMS: Reduction of atrial fibrillation (AF) burden is the preferred outcome measure over categorical AF rhythm recurrence after AF ablation. In this sub-analysis of the TeleCheck-AF project, we tested the feasibility of smartphone app-based approximation of time spent with AF and/or symptoms. METHODS AND RESULTS: Patients scheduled for at least one teleconsultation during the 12-month follow-up after AF ablation were instructed to use a smartphone photoplethysmography-based application for simultaneous symptom and rhythm monitoring three times daily for 1 week. Proxies of time spent with AF and/or symptoms (% recordings, load, and % days), temporal aggregation of AF and/or symptoms (density), and symptom-rhythm correlation (SRC) were assessed. In total, 484 patients (60% male, 62 ± 9.9 years) were included. Adherence, motivation, and patient satisfaction were high. %AF recordings, AF load, and %AF days (rs = 0.88-0.95) and %symptom recordings, symptom load, and %symptom days (rs = 0.95-0.98) showed positive correlations. The SRC correlated negatively with time spent with symptoms (rs = -0.65-0.90) and with time spent with AF (rs = -0.31-0.34). In patients with paroxysmal AF before ablation and AF during the monitoring period, 87% (n = 39/44) had a low-density score <50% ('paroxysmal AF pattern') while 5% (n = 2/44) had a high-density score >90% ('persistent AF pattern'). Corresponding numbers for patients with persistent AF before ablation were 48% (n = 11/23) and 43% (n = 10/23), respectively. CONCLUSION: On-demand, app-based simultaneous rhythm and symptom assessment provides objective proxies of time spent with AF and/or symptoms and SRC, which may assist in assessing AF and symptom outcomes after AF ablation.

Accuracy and comprehensibility of chat-based artificial intelligence for patient information on atrial fibrillation and cardiac implantable electronic devices.

AIMS: Natural language processing chatbots (NLPC) can be used to gather information for medical content. However, these tools contain a potential risk of misinformation. This study aims to evaluate different aspects of responses given by different NLPCs on questions about atrial fibrillation (AF) and clinical implantable electronic devices (CIED). METHODS AND RESULTS: Questions were entered into three different NLPC interfaces. Responses were evaluated with regard to appropriateness, comprehensibility, appearance of confabulation, absence of relevant content, and recommendations given for clinically relevant decisions. Moreover, readability was assessed by calculating word count and Flesch Reading Ease score. 52, 60, and 84% of responses on AF and 16, 72, and 88% on CIEDs were evaluated to be appropriate for all responses given by Google Bard, (GB) Bing Chat (BC) and ChatGPT Plus (CGP), respectively. Assessment of comprehensibility showed that 96, 88, and 92% of responses on AF and 92 and 88%, and 100% on CIEDs were comprehensible for all responses created by GB, BC, and CGP, respectively. Readability varied between different NLPCs. Relevant aspects were missing in 52% (GB), 60% (BC), and 24% (CGP) for AF, and in 92% (GB), 88% (BC), and 52% (CGP) for CIEDs. CONCLUSION: Responses generated by an NLPC are mostly easy to understand with varying readability between the different NLPCs. The appropriateness of responses is limited and varies between different NLPCs. Important aspects are often missed to be mentioned. Thus, chatbots should be used with caution to gather medical information about cardiac arrhythmias and devices.

A novel screening tool to unmask potential interference between S-ICD and left ventricular assist device.

INTRODUCTION: In patients with a left ventricular assist device (LVAD), the subcutaneous implantable cardioverter-defibrillator (S-ICD) can be an alternative to transvenous ICD systems due to reduced risk of systemic infection, which could lead to extraction of the ICD as well as the LVAD. S-ICD eligibility is lower in patients with LVAD than in patients with end-stage heart failure without LVAD. Several reports have shown inappropriate S-ICD therapy in the coexistence of LVAD and S-ICD. The aim of the present study was to evaluate S-ICD eligibility in patients with LVAD using the established electrocardiogram (ECG)-based screening test as well as a novel device-based screening test to identify potentially inappropriate S-ICD sensing in this specific patient cohort. METHODS AND RESULTS: The present study included 115 patients implanted with an LVAD. The standard ECG-based screening test and a novel device-based screening test were performed in all patients. Eighty patients (70%) were eligible for S-ICD therapy with the standard ECG-based screening test. Performance of the novel device-based screening test identified device-device interference in 14 of these 80 patients (12%). CONCLUSION: Using a novel extended device-based S-ICD screening method, a small number of patients with LVAD deemed eligible for S-ICD with the standard ECG-based screening test exhibit device-device interference. Careful S-ICD screening should be performed in patients with LVAD, who are candidates for S-ICD therapy, to prevent inappropriate sensing or ICD therapy.

Use of the wearable cardioverter-defibrillator (WCD) and WCD-based remote rhythm monitoring in a real-life patient cohort.

The wearable cardioverter-defibrillator (WCD) was introduced to provide protection from sudden cardiac death (SCD) in patients with transiently elevated risk or during ongoing risk stratification. Benefits and clinical characteristics of routine WCD use remain to be assessed in larger patient populations. This study aims to identify determinants of WCD compliance, therapies, and inappropriate alarms in a real-life cohort. A total of 106 cases (68.9% male) were included between 11/2010 and 04/2016. WCD therapies, automatically recorded arrhythmia episodes, inappropriate WCD alarms, patient compliance, and outcome after WCD prescription were analyzed. Median duration of WCD use was 58.5 days. Average daily wearing time was 22.7 h. Compliance was reduced in patients ≤ 50 years. Three patients received WCD therapies (2.8%). In one case ventricular fibrillation (VF) was appropriately terminated with the first shock. Two patients received inappropriate WCD therapies due to WCD algorithm activation during ventricular pacemaker stimulation. One patient died of asystole while carrying a WCD (0.9%). Additional arrhythmias detected comprised self-terminating sustained ventricular tachycardia (VT; 2.8%), non-sustained VT (2.8%), and supraventricular arrhythmias (5.7%). Inappropriate WCD alarms due to over-/undersensing occurred in 77/106 patients (72.6%), of which 41 (38.7%) experienced ≥ 10 inappropriate WCD alarms during the prescription period. Thirteen patients (12.3%) displayed a mean of > 1 inappropriate alarms/day. WCD use was associated with high compliance and provided protection from VT/VF-related SCD. The majority of patients experienced inappropriate WCD alarms. Alterations in QRS morphology during pacemaker stimulation require consideration in WCD programming to prevent inappropriate alarms.

[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.

Baroreflex activation therapy in advanced heart failure: A long-term follow-up.

AIMS: Baroreceptor activation therapy (BAT) is a promising new treatment strategy for patients with heart failure with reduced ejection fraction (HFrEF). It provides symptomatic relief, improvement in left ventricular function and reduction of cardiac biomarkers. Data regarding the long-term effect of BAT on HFrEF are scarce. This retrospective, monocentric study aimed to assess long-term outcome in patients who underwent BAT. METHODS: Patients with HFrEF who received BAT at Hannover Medical School between 2014 and 2023 were followed until the latest available follow-up. Symptom burden, echocardiography and laboratory testing were assessed before BAT implantation and in subsequent follow-ups. RESULTS: Twenty-three patients (mean age 66 ± 10 years, 83% male) with HFrEF were included in the study. Aetiology of heart failure was ischaemic in 70%. The majority of patients (96%) suffered from New York Heart Association (NYHA) III with a mean left ventricular ejection fraction (LVEF) of 23 ± 8% and N-terminal pro-B-type natriuretic peptide (NT-proBNP) of 2463 ± 2922 pg/mL. A complication occurred in one patient during BAT implantation (4%). The mean follow-up was 3 ± 2 (max. 7.5) years. BAT reduced NYHA classification in 12 patients (52%) after 1 year, of which one patient remained in ameliorated NYHA for 7.5 years. Echocardiographic evaluation revealed significant improvement in LVEF by 9 ± 9% after 1 year (P < 0.001) and by 11 ± 9% (P = 0.005) after 2 years. In addition, BAT mildly reduced NT-proBNP in the first 2 years [non-significantly after 1 year by 396 ± 1006 pg/mL and significantly after 2 years by 566 ± 651 pg/mL (P = 0.039)]. Seven patients reaching the recommended replacement time underwent device exchange. Four patients died during observation time. CONCLUSIONS: BAT resulted in a substantial reduction in NYHA classification and improvement in LVEF that lasted over long-term follow-up in many patients. NT-proBNP level decreased interim in long-term follow-up. These findings highlight the long-term efficacy and potential benefits of BAT as a therapeutic intervention for patients with HFrEF.

[How to: clinical use of antiarrhythmic drugs]. / How to: Antiarrhythmika in der klinischen Anwendung.

Antiarrhythmic drugs are important for the noninvasive rhythm control therapy of heart rhythm disorders. Antiarrhythmic drugs, which can be categorized into subgroups based on their different effects on ion channels, are clinically used for various types of arrhythmias. Knowledge about these specific electrophysiological effects contributes to a better understanding in order to select the correct drug for each specific arrhythmia. This review summarizes mechanisms, indications, contraindications, and side effects of the different antiarrhythmic drugs and, thus, supports their adequate use in daily clinical routine.

The patient perspective on remote monitoring of implantable cardiac devices.

Aims: Remote monitoring for patients with cardiac implantable electronic devices (CIEDs) is well established in clinical routine and recommended by current guidelines. Nevertheless, data regarding patients' perceptions are limited. Therefore, this study aims to analyze the patient perspectives on the remote monitoring of cardiac devices in Germany. Methods and results: Patients with CIEDs and remote monitoring of all current manufacturers from three German centers were asked to participate. The questionnaire consisted of 37 questions regarding the patients' individual use and perspectives on remote monitoring. Survey participation was anonymous and on a voluntary basis. A total of 617 patients (71.6% men) participated. Most patients reported feeling well informed (69.3%) and reported having unchanged or improved coping (98.8%) since the start of remote monitoring. At least 39.7% of patients experienced technical problems regarding the transmitter, whereas most patients (60.3%) reported that they never noted technical issues. Older patients had significantly less interest than younger patients in using their own smartphones for data transfer (p < 0.001). Conclusion: Patients with remote follow-up of CIED reported that they felt well informed about the remote monitoring approach. Remote monitoring can support coping with their disease. With remote monitoring, patients experienced a prolongation of intervals of in-person follow-up visits, and especially younger patients would appreciate smartphone-based data transfer of their CIEDs.

Performance and feasibility of three different approaches for computer based semi-automated analysis of ventricular arrhythmias in telemetric long-term ECG in cynomolgus monkeys.

Computer-based analysis of long-term electrocardiogram (ECG) monitoring in animal models represents a cost and time-consuming process as manual supervision is often performed to ensure accuracy in arrhythmia detection. Here, we investigate the performance and feasibility of three ECG interval analysis approaches A) attribute-based, B) attribute- and pattern recognition-based and C) combined approach with additional manual beat-to-beat analysis (gold standard) with regard to subsequent detection of ventricular arrhythmias (VA) and time consumption. ECG analysis was performed on ECG raw data of 5 male cynomolgus monkeys (1000 h total, 2 × 100 h per animal). Both approaches A and B overestimated the total number of arrhythmias compared to gold standard (+8.92% vs. +6.47%). With regard to correct classification of detected VA event numbers (accelerated idioventricular rhythms [AIVR], ventricular tachycardia [VT]) approach B revealed higher accuracy compared to approach A. Importantly, VA burden (% of time) was precisely depicted when using approach B (-1.13%), whereas approach A resulted in relevant undersensing of ventricular arrhythmias (-11.76%). Of note, approach A and B could be performed with significant less working time (-95% and - 91% working time) compared to gold standard. In sum, we show that a combination of attribute-based and pattern recognition analysis (approach B) can reproduce VA burden with acceptable accuracy without using manual supervision. Since this approach allowed analyses to be performed with distinct time saving it represents a valuable approach for cost and time efficient analysis of large preclinical ECG datasets.

Patient motivation and adherence to an on-demand app-based heart rate and rhythm monitoring for atrial fibrillation management: data from the TeleCheck-AF project.

AIMS: The aim of this TeleCheck-AF sub-analysis was to evaluate motivation and adherence to on-demand heart rate/rhythm monitoring app in patients with atrial fibrillation (AF). METHODS AND RESULTS: Patients were instructed to perform 60 s app-based heart rate/rhythm recordings 3 times daily and in case of symptoms for 7 consecutive days prior to teleconsultation. Motivation was defined as number of days in which the expected number of measurements (≥3/day) were performed per number of days over the entire prescription period. Adherence was defined as number of performed measurements per number of expected measurements over the entire prescription period.Data from 990 consecutive patients with diagnosed AF [median age 64 (57-71) years, 39% female] from 10 centres were analyzed. Patients with both optimal motivation (100%) and adherence (≥100%) constituted 28% of the study population and had a lower percentage of recordings in sinus rhythm [90 (53-100%) vs. 100 (64-100%), P < 0.001] compared with others. Older age and absence of diabetes were predictors of both optimal motivation and adherence [odds ratio (OR) 1.02, 95% coincidence interval (95% CI): 1.01-1.04, P < 0.001 and OR: 0.49, 95% CI: 0.28-0.86, P = 0.013, respectively]. Patients with 100% motivation also had ≥100% adherence. Independent predictors for optimal adherence alone were older age (OR: 1.02, 95% CI: 1.00-1.04, P = 0.014), female sex (OR: 1.70, 95% CI: 1.29-2.23, P < 0.001), previous AF ablation (OR: 1.35, 95% CI: 1.03-1.07, P = 0.028). CONCLUSION: In the TeleCheck-AF project, more than one-fourth of patients had optimal motivation and adherence to app-based heart rate/rhythm monitoring. Older age and absence of diabetes were predictors of optimal motivation/adherence.

Stereotactic radioablation for ventricular tachycardia.

Non-invasive stereotactic radioablation of ventricular tachycardia (VT) substrate has been proposed as a novel treatment modality for patients not eligible for catheter-based ablation or in whom this approach has failed. Initial clinical results are promising with good short-term efficacy in VT suppression and tolerable side effects. This article reviews the current clinical evidence for cardiac radioablation and gives an overview of important preclinical and translational results. Practical guidance is provided, and a cardiac radioablation planning and treatment workflow based on expert consensus and the authors' institutional experience is set out.

[Interpretation of photoplethysmography: a step-by-step guide]. / Interpretation der Photoplethysmographie: Schritt für Schritt.

By applying photoplethysmography (PPG), the camera of the mobile phone can be used to remotely assess heart rate and rhythm, which was widely used in conjunction with teleconsultations within the TeleCheck-AF project during the coronavirus disease 2019 (COVID-19) pandemic. Herein, we provide an educational, structured, stepwise practical guide on how to interpret PPG signals. A better understanding of PPG recordings is critical for the implementation of this widely available technology into clinical practice.

[The ECG is the key]. / Das EKG ist der Schlüssel.

A 35-year-old man experienced respiratory agony while sleeping followed by a generalized seizure. Subsequent exclusively neurological diagnostics showed no pathological findings. Four months later, the patient suffered a sudden cardiac death due to ventricular fibrillation, which he survived without neurological deficit. After initially unremarkable diagnostics, the diagnosis could be made electrocardiographically. Following a special pharmacological therapy, the patient remained free from further episodes of ventricular fibrillation in the long-term follow-up.

Eligibility for subcutaneous implantable cardioverter-defibrillator in patients with left ventricular assist device.

PURPOSE: The subcutaneous implantable cardioverter-defibrillator (S-ICD) could be a promising alternative to the conventional transvenous ICD in patients with LVAD due to its reduced risk of infection. However, surface ECG is altered following LVAD implantation and, since S-ICD detection is based on surface ECG, S-ICD could be potentially affected. The aim of the present study was to analyze S-ICD eligibility in patients with LVAD. METHODS: Seventy-five patients implanted with an LVAD were included in this prospective single-center study. The ECG-based screening test and the automated screening test were performed in all patients. RESULTS: Fifty-five (73.3%) patients had either a positive ECG-based or automated screening test. Out of these, 28 (37.3%) patients were found eligible for S-ICD implantation with both screening tests performed. ECG-based screening test was positive in 50 (66.6%) patients; automated screening test was positive in 33 (44.0%) patients. Three ECG-based screening tests could not be evaluated due to artifacts. With the automated screening test, in 9 (12.0%) patients, the test yielded no result. CONCLUSIONS: Patients implanted with an LVAD showed lower S-ICD eligibility rates compared with patients without LVAD. With an S-ICD eligibility rate of maximal 73.3%, S-ICD therapy may be a feasible option in these patients. Nevertheless, S-ICD implantation should be carefully weighed against potential device-device interference. Prospective studies regarding S-ICD eligibility before and after LVAD implantation are required to further elucidate the role of S-ICD therapy in this population.

Eligibility for subcutaneous implantable cardioverter-defibrillator in adults with congenital heart disease.

AIMS: Patients with adult congenital heart disease (ACHD) carry an increased risk for sudden cardiac death. Implantable cardioverter-defibrillator (ICD) therapy may be challenging in these patients due to anatomical barriers, repeated cardiac surgery, or complicated transvenous access. Thus, the subcutaneous ICD (S-ICD) can be a promising alternative in this patient population. Patients with ACHD show significant electrocardiogram (ECG) abnormalities, which could affect S-ICD sensing because it depends on surface ECG. METHODS AND RESULTS: One hundred patients with ACHD were screened for S-ICD eligibility. Standard ECG-based screening test and automated S-ICD screening test were performed in all patients. Sixty-six patients (66%) were male. Underlying congenital heart disease (CHD) was mainly CHD of great complexity (71%) and moderate complexity (29%), including repaired tetralogy of Fallot (20%), which was the most common entity. Thirty-seven patients (37%) already had a pacemaker (23%) or ICD (14%) implanted. Automated screening test identified 83 patients (83%) eligible for S-ICD implantation in either left parasternal position (78%) or right parasternal position (75%). Absence of sinus rhythm, QRS duration, and a paced QRS complex were associated with S-ICD screening failure in univariate analysis. Receiver operating characteristic curve and multivariate analysis revealed a QRS duration ≥148 ms as the only independent predictor for S-ICD screening failure. CONCLUSIONS: Patients with ACHD show satisfactory eligibility rates (83%) for S-ICD implantation utilizing the automated screening test, including patients with CHD of high complexity. S-ICD therapy should be considered with caution in ACHD patients with a QRS duration ≥148 ms and/or need for ventricular pacing.

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.

[It's all over! : Complications in the EP lab and their solutions]. / Jetzt ist alles aus! : Komplikationen im EPU-Labor und ihre Lösungen.

In cardiac electrophysiology, invasive procedures like catheter ablations or device implantations are getting increasingly complex. This poses challenges especially for electrophysiologists in training, not only to learn how to perform the procedure, but also how to manage possible complications. The present article uses exemplary case studies to present how to control complications and how to avoid them. The presented cases deal with complications such as air embolism in left atrial procedures, iatrogenic vascular injuries such as aortic dissection or dissection of the coronary sinus, complications and challenges with lead revisions, and pericardial tamponade. In each case, measures for avoidance as well as practical guidance for management are shown when the respective complication occurs.