CASE SUMMARY:A 58-year-old man underwent surgical resection of a left atrial myxoma with concomitant mitral valve repair. Postoperatively, progressive atrioventricular conduction disturbances were observed, evolving from Wenckebach periodicity to a multilevel atrioventricular block. TAKE-HOME MESSAGE:This case underscores the importance of a detailed electrocardiographic analysis to identify multilevel atrioventricular block and to avoid misclassification as complete atrioventricular block, with implications for prognosis and management.

Background:Catheter ablation for atrial arrhythmias is a common procedure with the possibility of causing complications, typically involving vascular access sites or cardiac tamponade. However, hepatic haemorrhage as a complication of cardiac catheter ablation is extremely rare. We present a case of life-threatening intra-abdominal bleeding originating from a hepatic vein following a catheter ablation for atrial tachycardia. Case summary:A 67-year-old man with a history of mitral valve repair and multiple ablation procedures for atrial fibrillation, atrial flutter, and macro-reentrant atrial tachycardia (MRAT) underwent a redo catheter ablation for MRAT. After the procedure, he developed right flank pain, hypotension, and a drop in haemoglobin. Imaging revealed extensive hemoperitoneum, originating near the right hepatic vein. Angiography of the visceral arteries was performed on which no major source of bleeding was identified. Because of persisting haemodynamic instability, the patient underwent emergency laparoscopy during which a capsular venous bleeding on the caudal liver surface was identified, likely caused by transient guidewire passage and injury in the hepatic veins. The bleeding was cauterized, and abdominal lavage was performed to clear the hemoperitoneum. He was transferred to the ICU for vasopressor support. Anticoagulation was restarted 1 week later, and the patient was discharged in stable condition. Conclusion:This case highlights a rare but serious complication of catheter ablation. Prompt recognition of intra-abdominal haemorrhage and a multidisciplinary approach involving cardiology, radiology, and surgery were crucial for a successful outcome. Operators should remain vigilant for atypical bleeding complications in ablation procedures and be prepared to initiate rapid intervention.

Aims:Electrical activation mapping is essential for identifying ablation targets in the treatment of cardiac arrhythmias. This study investigates high-frame-rate (HFR) speckle-tracking echocardiography (STE) as a non-invasive alternative to conventional electrophysiologic studies for constructing mechanical activation maps and defining left ventricular (LV) activation onset. Methods and results:Twenty healthy volunteers (HV) and 25 patients with a biventricular pacemaker (BiV) underwent HFR ultrasound scanning. Patients were scanned during BiV on and off, hence reintroducing native activation-left bundle branch block (LBBB) pattern. Five patients were additionally scanned after changing the LV lead pacing pole. A custom-made 2D-HFR-STE algorithm tracked the cardiac wall in the three conventional apical echocardiographic views. Strain rate (SR) curves were computed for each wall segment in a 16-segment LV model to measure the time between electrical and mechanical activation (i.e. time between QRS onset and first positive-to-negative zero-crossing in the SR curve). The timings were displayed in a bull's-eye plot, representing each subject's activation map. For most HV, activation started from mid-anteroseptum, at 23 ± 5 ms, spreading basal-inferolaterally at 50 ± 8 ms. During BiV off, the average septal activation was 36 ± 2 ms; the average lateral was 81 ± 21 ms (P < 0.01). During BiV on, the respective times were 53 ± 6 ms and 52 ± 6 ms (P = 0.3). Altering the LV lead pacing pole changed the lateral wall activation onset accordingly. Conclusion:HFR-STE was able to map normal activation, measure the known septal-to-lateral LBBB dyssynchrony, and identify the paced segment in 92% of the cases. HFR-STE could be a promising tool in constructing LV activation maps.

Advances in surgical techniques have substantially improved survival in patients with repaired tetralogy of Fallot (ToF). However, residual lesions following repair may lead to long-term complications, including arrhythmias and the need for device therapy. We conducted a retrospective single-center cohort study including patients who underwent surgical repair of ToF between 1960 and the present. Patients were categorized into three treatment eras (<1980, 1980-2000, >2000). Data on surgical strategy, mortality, arrhythmias, and cardiac implantable electronic device (CIED) implantation were collected from institutional databases. A total of 640 patients were included, of whom 360 (56.3%) underwent transannular patch (TAP) repair and 280 (43.7%) underwent non-TAP repair. Overall mortality was 7.2%, with cardiac causes accounting for 41.3% of deaths. Arrhythmias occurred in 14.4% of patients and were more frequently observed in those who underwent TAP repair (18.8%). CIED implantation was required in 7.5% of patients, most commonly implantable cardioverter defibrillators. The incidence of arrhythmias decreased across treatment eras, whereas overall survival did not differ significantly between eras. Long-term survival after surgical repair of ToF is favorable. Arrhythmias remain an important late complication, particularly in patients who underwent TAP repair, although their frequency appears to have decreased in more recent treatment eras. These findings underscore the long-term impact of initial surgical strategy on arrhythmic outcomes.

BACKGROUND:Rate-dependent left bundle branch block (LBBB) during exercise testing is traditionally considered a potential marker of coronary artery disease (CAD), yet the long-term prognosis remains uncertain. This study assessed the long-term outcomes of patients presenting with rate-dependent LBBB during exercise testing. METHODS:In this retrospective single-centre cohort study, all bicycle exercise tests performed between 2000 and 2022 were reviewed. Patients with transient LBBB developing during exercise and resolving during recovery were included. Baseline characteristics, diagnostic work-up, and long-term outcomes were collected. The primary endpoint was progression to permanent LBBB. Secondary endpoints included new-onset left ventricular systolic dysfunction, cardiac implantable electronic device (CIED) implantation, and all-cause mortality. RESULTS:Among 46,089 patients undergoing 51,220 exercise tests, 68 patients (0.15%) exhibited rate-dependent LBBB. Median age was 59.7 years (54.6-68.4) and 59.4% were male. CAD was present in 29.4%, while baseline heart failure was present in 11.8%. Rate-dependent LBBB occurred at a median heart rate of 126 bpm. During a median follow-up of 12.8 years (8.7-20.2), permanent LBBB developed in 36 patients (52.9%), with cumulative incidence of 46.5% at 10 years. New-onset systolic dysfunction occurred in 12 patients (17.6%), most often after or concurrent with permanent LBBB. CIED implantation was required in 12 patients (17.6%). All-cause mortality was 29.4% (8.1% at 10 years), with age as only independent predictor. CONCLUSIONS:Rate-dependent LBBB is uncommon but frequently progresses to permanent LBBB and is associated with subsequent systolic dysfunction. These findings suggest that rate-dependent LBBB may represent an early manifestation of intrinsic conduction system disease.

Background Risk stratification for ventricular arrhythmia in congenital heart disease (CHD) remains challenging, and the role of programmed ventricular stimulation is incompletely defined. Objective This study evaluated long-term outcomes after electrophysiology study (EPS) for ventricular arrhythmia assessment in CHD practice. Methods Retrospective, single-center cohort study including consecutive patients with structural CHD who underwent EPS with programmed ventricular stimulation for ventricular arrhythmia evaluation between 1995 and 2022. Baseline characteristics were compared between inducible (EPS+) and non-inducible (EPS-) patients. The primary outcomes were a composite of all-cause mortality and heart transplantation (HTX) and a composite ventricular arrhythmia (VA) outcome. Results Among 174 patients, median age at EPS was 33.8 years (IQR 24.1-46.1), 65 (37.4%) were female, 106 (60.9%) had conotruncal CHD, and 37 (21.3%) were EPS+. EPS+ patients more often had conotruncal CHD, abnormal RVEF, and longer PR and QRS duration. During a median follow-up of 13.0 (8.1-19.4) years, there was no significant difference in mortality/HTX (EPS+ 24.3% vs EPS- 18.2%, log-rank p=0.924) or VA outcome (EPS+ 27.0% vs 12.4%, log-rank p=0.113) between EPS+ and EPS- patients. After a median time of 2.8 (0.3-4.5) years 28 EPS- patients (20.4%) received an ICD. Of these, 16 (57.1%) received the ICD for out-of-hospital cardiac arrest or sustained ventricular tachycardia. Conclusions In patients with CHD referred for EPS for ventricular arrhythmia evaluation, a positive EPS was associated with a distinct phenotype but not with worse long-term mortality/HTX or VA outcome. A negative EPS did not exclude clinically relevant arrhythmic risk.

BACKGROUND:Stereotactic arrhythmia radioablation (STAR) is a novel, non-invasive treatment for therapy-refractory ventricular tachycardia (VT). In STAR, a high dose of radiation is used to non-invasively target and treat the VT substrate. Initial studies indicate promising VT burden reduction, but comprehensive efficacy and safety evaluations remain limited. METHODS:A systematic review (Preferred Reporting Items for Systematic Reviews and Meta-Analyses/Meta-analysis Of Observational Studies in Epidemiology guidelines) included studies on STAR for monomorphic VT identified up to 30 June 2024 via MEDLINE and EMBASE. Outcomes assessed were freedom of VT, percentage reduction in VT episodes and implantable cardioverter-defibrillator (ICD) shocks per month, survival and adverse events (AEs). Meta-analyses included prospective and retrospective studies only, using random-effects models with double arcsine transformation. Subgroup analyses by study design and planning target volume (PTV) were performed. AEs were qualitatively analysed and classified by organ system, severity and causality. RESULTS:The meta-analysis included 215 patients from 22 studies (age 66.0±4.4 years, 85.9% men, left ventricular ejection fraction 29.8±5.0%, 52.2% ischaemic cardiomyopathy, mean follow-up of 11.9±6.6 months). The overall survival was 69.6% (95% CI 62.6% to 76.2%). VT episodes and ICD shocks/month reduced by 81.5% (95% CI 64.2% to 94.8%) and 84.7% (95% CI 65.1% to 98.1%), respectively. However, only 23.1% (95% CI 10.7% to 37.7%) were VT-free at the end of follow-up. There were no significant differences in clinical outcomes between prospective and retrospective studies, nor between studies with high PTV and low PTV. A total of 352 AEs were reported in 280 patients, with a mean of 1.26 AE per patient. Of these AEs, 50.6% were classified as severe, though only 9.7% were likely STAR-related. CONCLUSIONS:STAR significantly reduces VT episodes and ICD shocks, offering symptomatic relief. However, high recurrence rates and severe AEs underscore the need for protocol optimisation and multidisciplinary collaboration to improve STAR's safety and efficacy in VT management.

AIMS:Chronotropic incompetence (CI), defined as the inability of the heart to appropriately increase its rate in response to exercise, is associated with exercise intolerance and adverse events. However, the diagnostic criteria for CI vary widely, limiting their clinical applicability and comparability across studies. Here we aim to systematically map the current definitions of CI and the prediction models used to estimate age-predicted maximal heart rate (APMHR). We illustrate how this diagnostic variability affects the identification of CI in patients enrolled in a cardiac rehabilitation program. METHODS:A scoping review systematically identified all published definitions of CI and prediction models for APMHR. A retrospective study evaluated the agreement between definitions in patients participating in cardiac rehabilitation. RESULTS:A total of 86 studies were included. Seventeen distinct methods to define CI were identified, ranging from absolute or relative peak heart rate parameters to approaches incorporating workload. In many cases, the applied cut-off values lacked a rationale. In parallel, numerous APMHR formulas were identified, differing by sex, age category, fitness level, clinical status, and the use of beta-blocker therapy, showing limited accuracy. In the clinical setting agreement between four major definitions was poor and pairwise comparisons between them showed significant differences in classification. CONCLUSION:Current methods to define CI and predict APMHR are inconsistent and problematic. This review provides a practical framework for selecting a context-appropriate definition and formula. It identifies current methodological gaps and highlights the need for future research to establish a consensus definition of CI.

BACKGROUND:Atrial fibrillation (AF) is a common arrhythmia with high morbidity and mortality. Pulsed-field ablation (PFA) is an emerging non-thermal treatment for AF, offering potential advantages over conventional radiofrequency ablation (RFA) and cryoballoon ablation (CBA) in terms of safety and efficacy. METHODS:This systematic review, registered in PROSPERO and conducted in line with PRISMA-P guidelines, assessed the efficacy and safety of PFA compared to conventional ablation methods (radiofrequency and cryoballoon) for treating paroxysmal AF in adults. A comprehensive literature search (2019-2025) was performed across multiple databases, with independent screening, data extraction, and bias assessment conducted by two reviewers using validated tools (RoB 2 and ROBINS-I), culminating in a qualitative synthesis due to study heterogeneity. RESULTS:PFA demonstrates promising efficacy in paroxysmal AF, with freedom from atrial arrhythmias at 12 months comparable to CBA and RFA. It also shows comparable first-pass pulmonary vein isolation (PVI) rates and shorter procedure time. Safety outcomes are favourable, with low incidence of adverse events, including no reported atrioesophageal fistulas, low rates of coronary spasm (0.14%) and haemolysis-related kidney injury (0.03%). CONCLUSION:PFA is an effective and safe alternative to traditional ablation techniques in paroxysmal AF. Further research through large-scale registries and long-term surveillance is needed to address rare complications and fully assess its safety profile.

Aims Developing an integrated care pathway for atrial fibrillation (AF) patients is of pivotal importance, given the different treatment strategies. Moreover, knowledge about the condition is an important factor in engaging patients in their care. Patient education formed the core of the integrated AF-EduCare/AF-EduApp approach. The main aim of this manuscript is to report the impact of this approach on AF and risk factor (RF)-related knowledge and self-care awareness. Methods and results Atrial fibrillation patients (n = 1232) were randomized to standard care (SC) or three educational interventions: in-person, online, or app-based education. Patients in the intervention groups received targeted education based on their responses to the Jessa Atrial fibrillation Knowledge Questionnaire (JAKQ) and a Self-Care Questionnaire (SCQ) presented at different time points. Patients who received educational follow-up reached a significantly higher knowledge score (in-person: 86.5 +/- 13.2%; online: 82.5 +/- 19.3%; app: 80.1 +/- 15.0%) than the SC group (65.3 +/- 16.6%) after 12/18 months (P < 0.001). The knowledge rapidly improved with the first sessions (i.e. 3 months) and remained sustained in all education groups. Patients with RF at baseline showed a slight but significant increase in awareness about their RF through education [e.g. no knowledge of last measured systolic blood pressure compared between education vs. SC: odds ratio of 0.45 (P = 0.012)], a change that was not seen in SC patients. Nevertheless, patients keep under-estimating the presence of their own RFs compared with objective documentation in their medical record (e.g. hypertension). Conclusion The JAKQ and SCQ are good instruments to provide targeted education to AF patients in daily clinical care. Knowledge level increases clinically significantly, but the impact on awareness about personal risk factors remains unsatisfactory.

Introduction:Patients with atrial septal defect (ASD) and patent foramen ovale (PFO) are prone to atrial arrhythmias due to structural and surgical alterations. While radiofrequency catheter ablation (RFCA) is a common treatment, arrhythmia recurrence remains a clinical challenge. This study aimed to assess arrhythmia patterns, procedural outcomes, and long-term recurrence following electrophysiological interventions. Methods:A retrospective cohort study was performed at a tertiary center including patients with ASD or PFO undergoing invasive electrophysiological procedures. Clinical and procedural data were extracted from medical records. Arrhythmias were classified based on electrocardiographic and electrophysiological findings. Kaplan-Meier analysis was used to assess event-free survival for arrhythmia recurrence. Results:Among 87 patients (57.5 % female, median age 46.4 years), 82.8 % underwent RFCA as the first intervention. The most common arrhythmias were non-cavo-tricuspid isthmus (CTI) dependent intra-atrial reentrant tachycardia (35.4 %) and atrial fibrillation (18.6 %). Acute procedural success was achieved in 97.2 % of patients. Recurrence-free survival after the first RFCA was 83.6 % at 1 year, 64.2 % at 3 years, and 60.0 % at 5 years. After the last RFCA, recurrence-free survival improved to 88.3 % at 1 year and 74.3 % at 5 years. Conclusion:In patients with ASD and PFO, RFCA is safe and acutely effective but followed by arrhythmia recurrence in a quarter of patients. The evolving arrhythmic substrate highlights the need for early intervention strategies and emerging technologies to optimize long-term outcomes in this patient population.

Background Atrial arrhythmias (AA) and heart failure (HF) are major causes of hospitalisation in adult congenital heart disease (ACHD). This study aimed to evaluate the temporal relationship between AA and HF onset, the association between HF and the success of radiofrequency ablation (RFA), and how HF influences outcomes in patients with AA.Methods In this single-centre retrospective cohort study, data from 3995 patients with ACHD were analysed. Dates of first AA and HF presentations were documented, and outcomes of RFA, including acute and long-term success, were assessed. All-cause mortality was compared between patients with AA and those with both AA and HF.Results The median age at last follow-up was 33 years (IQR 26-42). AA was observed in 348 patients (8.7%), and HF in 256 (6.4%). Among patients who developed both AA and HF (n=130), AA preceded HF in 79% of cases, with a median interval of 6 years (IQR 2-13) before HF diagnosis. In the remaining cases, AA occurred after HF diagnosis (median 2 years, IQR 1-6). RFA was performed in 119 patients (34.2%), 45 of whom had HF. Two years after RFA, 72% of patients were free from AA recurrence. Patients without HF had higher acute success rates (98% vs 90%) and lower recurrence rates (48% vs 76%) than those with HF. Patients with AA with HF had worse overall survival compared with those without HF.Conclusions In patients with ACHD, AA frequently precedes HF by several years. RFA can be an effective treatment for AA, but acute success is lower and recurrence rate higher when HF is present.

Aims Trials on integrated care for atrial fibrillation (AF) showed mixed results in different AF populations using various approaches. The multicentre, randomized AF-EduCare trial evaluated the effect of targeted patient education on unplanned cardiovascular outcomes. Methods and results Patients willing to participate were randomly assigned to in-person education, online education, or standard care (SC) and followed for minimum 18 months. Education focused on four aspects of integrated AF care: (i) knowledge on AF and oral anticoagulation; (ii) reinforcement of medication adherence; (iii) awareness about risk factors; and (iv) reachability for AF-related questions. The primary endpoint was the composite of cumulative events of unplanned cardiovascular hospitalizations and consultations, emergency department visits for cardiovascular reasons, and cardiovascular death. A total of 1038 patients (69.8 +/- 9.2 years) were followed up for 26.9 +/- 9.4 months. Education (both in-person and online) significantly improved AF-related knowledge compared to SC (P < 0.001), increased patient awareness about risk factors, led to high medication adherence, and encouraged patients to ask health-related questions. However, in-person education did not show an effect on the primary outcome compared to SC [HR 1.02 (0.91-1.14); P = 0.80] that was also not the case when comparing online education vs. SC [HR 1.18 (0.95-1.46), P = 0.65]. Exploratory subgroup analyses showed a heterogeneous effect over the centres, but a positive impact of in-person education in patients with asymptomatic AF, being 70 years old or younger, and without a history of heart failure. Conclusion AF-EduCare showed that intensive targeted patient education did not lead to less unplanned cardiovascular events in the AF patient population as a whole, although subgroups might benefit.