{"title":"[Basics in the EP lab-how and when to pace?]","authors":"Ann-Kathrin Kahle, Christian Meyer","doi":"10.1007/s00399-026-01153-6","DOIUrl":"10.1007/s00399-026-01153-6","url":null,"abstract":"<p><p>Electrical stimulation is a central tool in the evaluation and management of arrhythmias in the electrophysiological laboratory. Targeted atrial and ventricular pacing maneuvers allow induction, mechanistic characterization, and termination of arrhythmias. This provides important insights into the involved conduction pathways, anatomical location, and the underlying arrhythmogenic substrate, thereby forming the basis for a tailored ablation strategy. A structured approach even prior to the first stimulation maneuver establishes the foundation for successful diagnosis and therapy (ensuring stable catheter positions, optimal signal quality, and reliable capture). Understanding fundamental principles such as incremental, programmed, burst and overdrive stimulation is essential for accurate interpretation of electrophysiological responses. The consolidation of knowledge over the past three decades has helped ensure that, today, a few key maneuvers are usually sufficient to enable a rapid and reliable diagnosis. These play a key role in differentiating regular narrow-complex tachycardias, distinguishing wide-complex tachycardias, and identifying reentrant vs. nonreentrant mechanisms. They are also indispensable for assessing procedural endpoints after ablation, including confirmation of noninducibility of the clinical tachycardia or successful pulmonary vein isolation. The present review further outlines practical solutions to common challenges such as inconsistent pacing responses, far-field signals, and nonreproducible arrhythmia induction. Overall, systematic application of pacing maneuvers enables precise mechanistic classification of tachycardias and significantly contributes to safe, efficient, and individualized electrophysiological therapy.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"338-351"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147935464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stefano Bordignon, Boris Rudic, Alexander Langanke Kohls, Nils Malte Sönksen, Sara Würfel, Benedikt Götsch, Ulrich Hink
{"title":"Differential diagnosis of wide-complex tachycardia: ventricular or supraventricular?","authors":"Stefano Bordignon, Boris Rudic, Alexander Langanke Kohls, Nils Malte Sönksen, Sara Würfel, Benedikt Götsch, Ulrich Hink","doi":"10.1007/s00399-026-01163-4","DOIUrl":"10.1007/s00399-026-01163-4","url":null,"abstract":"<p><p>Wide-complex tachycardia (WCT) represents one of the most challenging diagnoses in clinical cardiology and emergency medicine, requiring rapid and accurate differentiation between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) with aberrant conduction. Misclassification carries significant clinical consequences, as the two entities differ substantially in prognosis and management. This review aims to provide a comprehensive overview of the electrocardiographic approach to the differential diagnosis of WCT, with particular focus on the physiological rationale underlying the diagnostic criteria included in the major diagnostic algorithms. A thorough understanding of these electrocardiographic principles remains essential for any physician encountering WCT in clinical practice.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"271-279"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148680712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wilhelm Haverkamp, Gerhard Hindricks, Nils Strodthoff
{"title":"[AI-Assisted ECG diagnostics : Classical test statistics still apply].","authors":"Wilhelm Haverkamp, Gerhard Hindricks, Nils Strodthoff","doi":"10.1007/s00399-026-01158-1","DOIUrl":"10.1007/s00399-026-01158-1","url":null,"abstract":"<p><p>Artificial intelligence (AI) is revolutionizing electrocardiography with impressive performance metrics. However, these figures can be misleading if classical test statistics-particularly pretest probability-are not considered. Bayes' theorem demonstrates that even excellent AI algorithms can produce numerous false-positive results when disease prevalence is low. Likelihood ratios provide prevalence-independent assessment; calibration and clinical net benefit complement discrimination metrics such as area under the curve (AUC). Physicians must understand the epidemiological context of their patient populations and interpret AI results critically-not noncritically adopt algorithmic decisions.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"321-326"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13503445/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148303979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoe Vogel, Carmen Kolokowsky, Roman Michalski, Daniel Sedding, Arash Arya
{"title":"Value of the 12-lead ECG to localize the origin of ventricular tachycardia.","authors":"Zoe Vogel, Carmen Kolokowsky, Roman Michalski, Daniel Sedding, Arash Arya","doi":"10.1007/s00399-026-01167-0","DOIUrl":"10.1007/s00399-026-01167-0","url":null,"abstract":"<p><p>The 12-lead electrocardiogram (ECG) recorded during ventricular tachycardia (VT) remains a simple, universally available tool for VT localization. In idiopathic VT, QRS morphology and polarity often reflect the site of earliest activation and can facilitate targeted mapping. In patients with structural heart disease, however, the surface ECG predominantly represents the VT exit region rather than the critical diastolic isthmus; thus, its main clinical value lies in regionalization and in planning ablation strategy and access. A pragmatic stepwise interpretation integrating V1 morphology, precordial transition (V1-V6), and the frontal plane axis can localize VT in most cases, although accuracy is influenced by scar size, conduction abnormalities, antiarrhythmics, and variable exit sites. Emphasis is placed on estimating epicardial or intramural involvement using interval- and morphology-based criteria-especially in nonischemic cardiomyopathy-and on integrating ECG findings with cardiac scar imaging. Key disease-specific ECG patterns are highlighted. Electrocardiographic imaging, automated ECG analysis, and artificial intelligence (AI)-based localization approaches may further improve VT localization.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"288-300"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148702646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"In memoriam Dr. Heinz Friedrich Pitschner.","authors":"Jörg Neuzner, Ulrich Michel","doi":"10.1007/s00399-026-01162-5","DOIUrl":"10.1007/s00399-026-01162-5","url":null,"abstract":"","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"363-364"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148537721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Imaging phenotypes and substrates in ventricular tachycardia.","authors":"Pranav Bhagirath, Ivo Roca-Luque","doi":"10.1007/s00399-026-01161-6","DOIUrl":"10.1007/s00399-026-01161-6","url":null,"abstract":"<p><p>Ventricular tachycardia (VT) remains challenging, as the underlying substrate is heterogeneous and not adequately described by scar burden alone. Imaging is increasingly used to identify structural heart disease, characterize myocardial abnormality, and support VT ablation planning. Distinct imaging findings reflect specific myocardial phenotypes and substrate architectures, such as ischemic scar, nonischemic fibrosis, inflammatory injury, and fibrofatty remodelling. These phenotypes do not represent the same arrhythmic substrate and do not carry the same implications for mechanism, procedural strategy, or follow-up. This review discusses VT in terms of imaging phenotype and substrate rather than scar alone. It also summarizes how imaging can define substrate location, depth, tissue composition, and spatial distribution, and how this may improve understanding of the arrhythmic ventricle. The therapeutic implications of this framework are then discussed, including relevance for treatment planning, interpretation of treatment effect, and assessment of recurrence. Finally, current limitations and future directions of imaging-based substrate assessment in VT are addressed.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"312-320"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148563534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K Weipert, K Roussopoulos, M Tsiakou, A Schuster, D Gündüz, D Erkapic
{"title":"[Ablation of an atrioventricular nodal reentrant tachycardia and a focal left atrial tachycardia in azygos continuation].","authors":"K Weipert, K Roussopoulos, M Tsiakou, A Schuster, D Gündüz, D Erkapic","doi":"10.1007/s00399-026-01134-9","DOIUrl":"10.1007/s00399-026-01134-9","url":null,"abstract":"<p><p>A 35-year-old woman with atrioventricular nodal reentrant tachycardia (AVNRT) and focal atrial tachycardia was found to have a rare congenital interruption of the inferior vena cava with azygos continuation. Slow-pathway ablation was successfully performed via the azygos vein. A second ablation of the left atrial tachycardia was successfully performed via transseptal access using an RF wire and a short steerable sheath via the right jugular vein. This case illustrates the successful use of an alternative access in complex venous anatomy.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":"327-332"},"PeriodicalIF":0.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13503457/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146222078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luca Nolte, Corinna Lenz, Max Olav Schrage, Hinrich Schroer
{"title":"Pseudo-pacemaker syndrome triggered by atrioventricular hysteresis algorithm activation in a patient with left bundle branch area pacing: a case report.","authors":"Luca Nolte, Corinna Lenz, Max Olav Schrage, Hinrich Schroer","doi":"10.1007/s00399-026-01166-1","DOIUrl":"https://doi.org/10.1007/s00399-026-01166-1","url":null,"abstract":"<p><p>Atrioventricular (AV) hysteresis algorithms are designed to minimize unnecessary ventricular pacing. This case report describes a young patient with left bundle branch area pacing (LBBAP) in whom activation of an AV-hysteresis algorithm resulted in excessive prolongation of AV intervals, leading to ineffective AV synchrony and recurrence of symptoms consistent with a pseudo-pacemaker syndrome despite permanent pacemaker implantation, including dizziness and near-syncope. The case highlights the importance of careful device programming, particularly in patients undergoing conduction system pacing.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148834619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Karl-Heinz Ladwig, Andreas Götte, Luise Ankerhold, Karoline Lukaschek
{"title":"[The role of psychosocial risk factors in the development and course of atrial fibrillation].","authors":"Karl-Heinz Ladwig, Andreas Götte, Luise Ankerhold, Karoline Lukaschek","doi":"10.1007/s00399-026-01170-5","DOIUrl":"https://doi.org/10.1007/s00399-026-01170-5","url":null,"abstract":"<p><strong>Background: </strong>Psychosocial risk factors are well established in the development of cardiovascular disease. However, their role in the onset and progression of atrial fibrillation (AF) has not yet been systematically summarised.</p><p><strong>Objective: </strong>To present the current evidence on psychosocial risk factors associated with the development and course of AF.</p><p><strong>Methods: </strong>A scoping review of epidemiological and population-based studies as well as relevant meta-analyses was conducted. Studies addressing psychosocial risk factors, including social, occupational, and psychological stressors, sleep disturbances, depression, anxiety disorders, and stress-related disorders were included.</p><p><strong>Results: </strong>Consistent associations were reported particularly for depression, insomnia, and work-related stress. For depression, risk increases ranging from 15% to 58% were reported. Large population-based cohort studies consistently demonstrated risk increases of 26% to 36% for insomnia. In addition, associations were observed for adverse childhood experiences, anxiety disorders, and post-traumatic stress disorder. Evidence regarding loneliness and social isolation was inconsistent. Proposed underlying mechanisms include autonomic, endocrine, and inflammatory pathways.</p><p><strong>Conclusion: </strong>Available evidence suggests that psychosocial factors make a relevant contribution to the development and maintenance of AF. Consideration of psychosocial stressors may complement current approaches to AF risk stratification and prevention. The existing evidence supports a stronger integration of psychosocial risk factors into future epidemiological research and clinical care concepts.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148801472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[33 years of pacemaker longevity-an unusual case].","authors":"Martin Koval, Timur Kyashif, Torsten Doenst","doi":"10.1007/s00399-026-01164-3","DOIUrl":"https://doi.org/10.1007/s00399-026-01164-3","url":null,"abstract":"<p><p>We report on an 86-year-old patient whose unipolar single-chamber pacemaker (Vitatron Ceryx 623), implanted in 1991 due to sinus node arrest, had been continuously active for 33 years without any replacement of the pacemaker unit. No routine outpatient check-up had been carried out for over a decade. The ECG revealed asynchronous ventricular pacing (VOO) at a fixed rate of 50/min, consistent with the manufacturer's defined EOS fallback mode. Despite the failure to switch modes, the patient remained clinically event-free. Upon replacement of the device, complete shell-like calcification of the pocket (\"porcelain pocket\") was observed; the lead measurements (stimulation threshold 0.5 V/0.4 ms, sensing 7.2 mV, impedance 351 Ω) were excellent, thus the lead was left in place. This case illustrates the remarkable long-term performance of older devices and leads, at the same time it underlines the need for a regular follow-up and the risks of asynchronous pacing in EOS mode.</p>","PeriodicalId":52403,"journal":{"name":"Herzschrittmachertherapie und Elektrophysiologie","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148708541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}