Search Results (90)

Ventricular tachycardia and sudden cardiac death remain the principal late causes of mortality in repaired tetralogy of Fallot. Clinical practice is evolving from a “reactive” paradigm centered on defibrillator therapy and post-event ablation toward a “proactive” paradigm targeting slowly conducting anatomical isthmuses before clinical arrhythmias become manifest. Monomorphic ventricular tachycardia in this population typically occurs due to a discrete, anatomically defined set of slowly conducting isthmuses bounded by surgical patches or incisions and valve annuli. Substrate-targeted catheter and surgical ablation are technically feasible, safe, and associated with high arrhythmia-free survival when complete bidirectional block is achieved. The current indication for “proactive” ablation is for substrate evaluation before transcatheter pulmonary valve replacement, after which endocardial access to the dominant isthmus may be permanently obscured. Pulmonary valve replacement alone does not abolish the arrhythmogenic substrate, thus providing the rationale for combining valve intervention with proactive ablation. This narrative review discusses substrate biology, risk stratification, comparative outcomes of reactive and proactive ablation strategies, and the role of pulmonary valve replacement. It also proposes an operational pathway integrating both approaches within shared decision-making. The ongoing CATAPULT-TOF study and subsequent multicenter work will determine the populations in which proactive substrate evaluation should become routine. Full article

Background: The presence of left atrial fibrosis is a marker of advanced remodeling and is associated with a worse outcome after pulmonary vein isolation (PVI). Conventional fluoroscopy-only cryoballoon ablation (CBA) lacks this prognostic information. The addition of electroanatomical mapping (EAM) using the inner lumen spiral catheter allows accurate voltage assessment of the left atrial posterior wall. However, the value of the finding of posterior wall low-voltage zones (pwLVZs) is unknown. Purpose: To study the value of left atrial voltage maps during CBA by comparing clinical and procedural characteristics and clinical outcome between patients with and without pwLVZs. Methods: A cohort of 250 consecutive patients who underwent index CBA for atrial fibrillation was analyzed. All patients underwent pre- and post-procedural EAM using the Achieve^TM catheter and EnSite^TM mapping system. The presence of LVZs was evaluated at the postprocedural voltage map of the posterior wall. Clinical success was defined as freedom from documented AF or atrial tachycardia (AT) >30 s after 1 year. Results: PwLVZs were found in 41/250 (16.4%) of patients. Patients with pwLVZs were older (69.3 ± 8.5 vs. 64.2 ± 10.4; p = 0.003), more frequently female (63.4% vs. 32.5%; p < 0.001) and had higher CHA₂DS₂-VASc scores (3.0 ± 1.6 vs. 2.0 ± 1.5; p < 0.001). The incidence of obesity (31.7% vs. 25.8%; p = 0.048), structural heart disease (35.5% vs. 17.4%; p = 0.021) and persistent AF (68.3% vs. 43.8%; p = 0.004) was higher in the pwLVZs group. Kaplan–Meier analysis of clinical outcome showed a higher recurrence rate in the pwLVZs group. The finding of pwLVZs was a predictor of atrial arrhythmia recurrence during follow-up (HR 2.583; 95%CI: 1.334–5.002; p = 0.005). Conclusions: In CBA facilitated by integrated EAM, pwLVZ was associated with older age, female sex, higher CHADS-VASc scores, obesity, structural heart disease and persistent AF. The finding of pwLVZs is predictive of a worse clinical outcome. Full article

Background: Epicardial mapping and ablation of ventricular tachycardia (VT) are used in different clinical situations but pericardial adhesions following prior cardiac surgery or previous epicardial procedures may limit a percutaneous approach. The objective of this case series is to evaluate the safety and feasibility of a hybrid approach with surgical epicardial access as a valid alternative when pericardial space is not accessible percutaneously. Methods: After a complete preprocedural evaluation, four patients with prior cardiac surgery underwent hybrid VT ablation under general anesthesia. Surgical subxiphoid access was performed in three cases and one patient was subjected to median resternotomy for concomitant open-heart surgery. Epicardial electroanatomic voltage maps were acquired using the CARTO 3 system (Biosense Webster) or NavX (St. Jude Medical) and VT ablations with irrigated catheters were performed. The procedural endpoint was VT non-inducibility and/or LAVA/LP abolition. Results: No serious periprocedural complications occurred after hybrid VT ablation. Three patients had no complex ventricular arrhythmias after a median follow-up of 43 months. A symptomatic sustained VT relapsed in one patient, without requiring a redo ablation procedure but responded to escalation of antiarrhythmic therapy. Conclusions: A carefully planned hybrid VT ablation with surgical epicardial access is a safe and feasible procedure in patients with epicardial scar-related re-entry circuits and pericardial adhesions that limit a percutaneous approach. Full article

Background/Objectives: The management of ventricular arrhythmias (VAs) within cardiac intensive care units (CICUs) is undergoing a significant transformation. This review aims to analyze the historical transition from a narrow focus on arrhythmia-specific treatments toward on the multidisciplinary heart rhythm team. Methods: A narrative revies was conducted. Results: Effective management of electrical storm (ES) requires prompt attenuation of sympathetic hyperactivity, with a preference for non-selective beta-blockers and the implementation of deep sedation. The use of mechanical circulatory support (MCS) has emerged as a mechanical antiarrhythmic strategy by facilitating ventricular unloading and reducing myocardial wall stress. Furthermore, early catheter ablation, guided by 3D electroanatomical mapping and advanced imaging, has proven superior to salvage procedures for stabilizing the arrhythmic substrate. Finally, the integration of palliative care ensures ethical stewardship during refractory shock. Conclusions: Modern VAs management in the CICUs represents a convergence of technology, biology, and multidisciplinary coordination. Full article

Background/Objectives: Electroanatomic mapping (EAM) provides high-resolution spatial and electrogram information, but the prognostic utility of quantitative EAM features has not been systematically evaluated with contemporary artificial intelligence (AI) methods. We investigated whether an AI analysis of quantitative EAM exports from the CARTO system enhances the prediction of major arrhythmic events (MAEs). Methods: In this retrospective, multicenter cohort study, 248 consecutive patients undergoing left ventricular EAM at four tertiary electrophysiology centers were analyzed. Numerical EAM descriptors (spatial coordinates, unipolar/bipolar voltages, local activation time, impedance) were transformed into derived metrics, including local activation heterogeneity (GR), late-potential extent (LAT), bipolar–unipolar discrepancy (VLT), and low-amplitude scar extent (Scar Areas), and were spatially normalized via spherical projection. Clinical, anamnestic, and imaging variables were integrated. Machine learning and deep learning models were trained with an 80:20 train/test split and evaluated using three-fold cross-validation. Performance metrics included area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, and precision. Results: Models incorporating both clinical and AI-processed EAM features achieved high discriminatory performance (test AUC up to 0.92; accuracy up to 0.896). Specificity was consistently high (≈0.97–0.998), whereas sensitivity remained modest (≈0.39–0.58). Among the EAM-derived features, GR was the most consistently informative predictor across algorithms and analyses; VLT, LAT, and Scar Areas also contributed substantially. Regionally, basal sub-mitral, subaortic, and posterolateral basal-to-mid zones exhibited the strongest associations with MAEs. Conclusions: AI-driven quantitative analysis of left ventricular EAM exports augments risk stratification for MAEs beyond conventional clinical and binary EAM descriptors. Reflecting local conduction heterogeneity, GR emerged as the dominant EAM predictor. Prospective validation in larger, disease-specific cohorts and real-time integration within EAM platforms are warranted. Full article

Background/Objectives: Transcatheter ablation assisted by three-dimensional (3D) electroanatomical mapping (EAM) is the elective treatment for atrioventricular nodal reentrant tachycardia (AVNRT) in children and adolescents. In this population of patients, the most frequently employed EAM strategies are the low-voltage bridge (LVB) strategy and sinus rhythm propagation mapping (SRPM). However, the exact pathophysiology and anatomy of the AVNRT reentrant circuits are still poorly understood. The aim of this study was to investigate the relationship between SRPM and LVB and to shed light on nodal physiology in children and adolescents affected by AVNRT. Methods: We retrospectively collected data on pediatric patients who underwent cryoablation for AVNRT assisted by high-density 3D EAM by using the LVB strategy; maps were reviewed by two independent electrophysiologists and the SRPM was described. SRPM was defined as typical when only one collision area was identified and atypical whenever either no or ≥ two collision areas were localized. Results: Twenty-eight consecutive patients (11.3 ± 3.3 years) were enrolled. All procedures were acutely successful. Overall, atypical SRPM was present in 10 patients (35.7%), and it did not correlate with the presence of multiple SPs or electrophysiological data. Moreover, we observed an imperfect concordance between SRPM and LVB (only in 10/18 patients). When SRPM and LVB were assessed in different locations, the LVB identified the effective cryoablation site in more cases than SRPM (4/8 vs. 1/8). Lastly, in cases of double collision, one collision area co-localized with the LVB and the effective cryoablation spot, whereas the other was located superiorly, closer to the His bundle. Conclusions: Atypical sinus rhythm propagation in the Koch’s triangle is a frequent finding in pediatric AVNRT patients. In this series, LVB showed closer concordance with the successful cryolesion site than retrospectively reconstructed SRPM. Full article

Background: Atrioventricular (AV) nodal re-entrant tachycardia (AVNRT) is strongly related to the anatomy and physiology of the AV nodal and junctional area. Objectives: This study aims to precisely ascertain the localization of structures within Koch’s triangle by employing the recording of nodal potentials in conjunction with the integration of three-dimensional electrical maps merged with computed tomographic images. Methods: Five consecutive patients with typical AVNRT and an available cardiac computed tomographic scan were enrolled. High-resolution mapping was performed prior to the initial ablation attempt. Results: The low-frequency, low-amplitude humped nodal potential was consistently detected within the presumed compact node location, found in the superior septal area in three patients and in the mid-paraseptal region in two cases. The length of the region was 4.5 ± 1.2 mm, with its width measured at 2.7 ± 0.6 mm (distance from the atrioventricular membranous septum = 3 ± 0.8 mm). The nodal potential was consistently recorded alongside the slow pathway potential in the infero-septal region, anterior to the orifice of the coronary sinus (distance from the slow pathway potential to the site of His potential = 15 ± 3.2 mm). This suggests that the slow pathway electrogram likely represented the medial or distal portion of the inferior nodal extension, rather than the node itself. In all patients, successful ablation was achieved, requiring a median of 5 [4–6] radiofrequency deliveries. No procedural complications were encountered. Conclusions: This study, which integrates three-dimensional electroanatomical maps with reconstructed computed tomographic datasets and utilizes specific anatomical landmarks, provides a reliable and accurate estimation of the atrioventricular conduction axis components in relation to the Koch’s pyramid boundaries. Full article

Management of ventricular tachycardia (VT) requires an integrated approach combining invasive therapy and cardiac imaging. This article reviews the principal imaging modalities and their integration with electroanatomical mapping systems to plan and guide procedures and to assess the success of VT ablation during follow-up. The central role of imaging in optimizing the efficacy and safety of VT ablation is emphasized. Studies demonstrating that imaging-supported workflows can improve substrate localization, reduce procedural times and radiation exposure, and lower recurrence rates are highlighted. Current limitations and future challenges are also discussed. Full article

Atrioventricular (AV) node ablation represents an established therapeutic option in the management of atrial fibrillation (AF) and other atrial tachyarrhythmias, particularly in patients with symptomatic tachycardia who remain unresponsive or intolerant to pharmacological therapy. The procedure is often considered in cases of refractory arrhythmias, antiarrhythmic drugs intolerance, or tachycardiomyopathy, and plays a key role in optimizing outcomes in patients undergoing cardiac resynchronization therapy, where achieving adequate biventricular pacing is otherwise compromised by rapid ventricular responses. Traditionally, AV node ablation is performed using radiofrequency energy delivered at the region of the His bundle, guided by the earliest His potential recordings. However, the anatomical complexity of the AV node and Koch’s triangle poses important challenges, including the risk of incomplete ablation, persistence of conduction, lack of reliable junctional escape rhythms, and increased risk of proarrhythmia. Recent advances in high-resolution mapping and electroanatomical guidance have enabled a more precise anatomical approach, selectively targeting the compact AV node while reducing collateral injury. These developments offer the potential for improved procedural safety, long-term efficacy, and a more standardized strategy for patient management. This review summarizes current evidence, techniques, and clinical implications of AV node ablation, highlighting its role in the evolving landscape of arrhythmia treatment. Full article

Background: Artificial Intelligence (AI) is a transformative innovation designed to enable machines to perform tasks typically requiring human intelligence. Among various medical fields, cardiology—and particularly electrophysiology—has seen rapid integration of AI technologies. The ability of AI to analyze large and complex datasets is reshaping diagnostic and therapeutic approaches. Objectives: This review aims to provide a comprehensive overview of AI models and their applications in cardiac electrophysiology. The focus is on understanding how AI contributes to clinical practice through ECG interpretation, arrhythmia detection, atrial mapping, and catheter ablation, while also exploring its limitations and future potential. Methods: The review discusses various AI approaches, including Machine Learning (ML) and Deep Learning (DL), and highlights relevant literature illustrating their implementation in electrophysiological settings. Key clinical applications are examined thematically, with a narrative synthesis of current capabilities, technologies, and outcomes. Results: AI-based tools have demonstrated effectiveness in identifying supraventricular arrhythmias like atrial fibrillation (AF) and atrial flutter (AFL), as well as complex conditions such as ventricular tachycardias (VTs) and long QT syndrome (LQTS). In procedural contexts, AI enhances electro-anatomical mapping, reduces operative time, and supports tailored post-ablation management. Discussion: While AI offers clear advantages in diagnostic accuracy and procedural efficiency, challenges remain regarding data security, ethical transparency, and clinical adoption. Addressing these limitations will be crucial for integrating AI into routine electrophysiology and maximizing its potential in future cardiology practice. Full article

Background: Pulse field ablation (PFA) is a novel ablation technology with efficacy and safety, potentially making it a preferred ablation technology for persistent atrial fibrillation (AF). There is no optimal procedural workflow established to optimize efficacy, limiting the number of PFA applications and risks of the procedure. Due to the importance of optimal catheter–tissue contact for effective pulse field ablation, a workflow combining superior left atrial intracardiac echo (ICE) imaging and electroanatomic mapping (EAM) is an attractive strategy for PFA of persistent AF. Methods: A detailed procedural workflow was developed for fluoroscopy-free PFA using a pentaspline ablation catheter supported by left atrial ICE and EAM, and a case series of its execution in 30 consecutive patients with persistent AF is presented. All patients underwent pulmonary vein and posterior wall isolation as the index procedure, followed by additional ablation targeting non-pulmonary vein triggers and other inducible atrial arrhythmias. Results: Left atrial ICE imaging and EAM guided procedure resulted in successful isolation of the pulmonary veins and posterior wall in all patients, with additional ablation of spontaneous arrhythmias or non-pulmonary triggers if induced. There were no major complications of the procedure. Average procedure times and short-term efficacy were comparable with reported PFA outcomes using traditional imaging techniques. Conclusions: Fluoroscopy-free PFA guided by left-sided ICE for persistent AF can be performed with superior catheter–tissue contact imaging in a safe manner with a comparable procedural time and short-term efficacy as reported with the use of other imaging modalities. Full article

Background/Objectives: Atrial fibrillation (AF) is the most common sustained arrhythmia, with catheter ablation outcomes differing significantly between paroxysmal and persistent forms. While pulmo-nary vein isolation (PVI) remains the cornerstone of ablation, persistent AF is often associ-ated with atrial remodeling and non-pulmonary vein triggers, reducing procedural success rates and necessitating repeat interventions. However, in selected patients with minimal atrial substrate, a single PVI may achieve durable rhythm control. This case report illus-trates such a scenario in a young patient with persistent AF and tachyarrhythmia-induced cardiomyopathy (TIC). Methods: A 42-year-old previously healthy male presented with newly diagnosed persistent AF complicated by TIC and heart fail-ure (left ventricular ejection fraction [LVEF] 25%). Despite rate control, anticoagulation, guideline-directed heart failure therapy, amiodarone pretreatment, and two failed electrical cardioversions, the patient remained symptomatic. Elec-troanatomic mapping was performed to assess atrial substrate prior to radiofrequency ablation. Results: Mapping revealed no extensive low-voltage zones, indicating absence of significant atrial fibrosis. During ablation, si-nus rhythm was restored spontaneously with a single application targeting the infero-posterior aspect of the right infe-rior pulmonary vein. No additional arrhythmogenic substrate was identified. The patient maintained sinus rhythm throughout 14 months of follow-up, with marked clinical improvement, normalization of LVEF (55%), regression of atrial and ventricular enlargement, and resolution of heart failure symptoms. Quality of life, assessed by the ASTA question-naire, improved from 24 to 0 points. Conclusions: This case highlights that even in therapy-resistant persistent AF with severe structural and functional cardiac impairment, arrhythmia may be driven by discrete pulmonary vein-dependent mechanisms. Careful patient selection, particu-larly in younger individuals without advanced atrial remodeling, can identify those in whom PVI alone achieves durable rhythm control and reverse cardiac remodeling. Full article

Background: The VARIPULSE platform is an advanced Pulsed Field Ablation (PFA) system fully integrated with electro-anatomical mapping system, employing a variable loop circular catheter (VLCC) for atrial fibrillation (AF) ablation. The objective of the study is to assess for the first time the feasibility, safety, and procedural impact of AI (artificial intelligence)-assisted ICE (intracardiac echocardiography) mapping with the CARTOSOUND FAM Module compared with conventional electroanatomical mapping during PFA. Methods: In this retrospective, multicenter study, 157 consecutive patients undergoing PFA for paroxysmal or persistent AF were included. Patients were divided into two groups: ICE-guided cohort (n = 64) and non-ICE-guided cohort (n = 93). Propensity score matching (PSM) was used to adjust for baseline differences. Results: AI-assisted ICE mapping was feasible in all cases. Compared with conventional mapping, it significantly reduced LA (left atrium) mapping time (median 5 vs. 8 min; p < 0.001), LA dwell time (33.5 vs. 38.5 min; p = 0.001), and fluoroscopy time (7.5 vs. 14 min; p < 0.001). The total number of PFA applications was similar across groups (p = 0.136). No major adverse events occurred in either cohort during the procedure or within the first month of follow-up. Conclusions: AI-assisted ICE mapping using the CARTOSOUND FAM Module enables accurate anatomical reconstruction and significantly optimizes procedural efficiency in PFA. This approach supports further development toward radiation-sparing and potentially fluoroscopy-free PFA workflows. For the first time, it addresses a gap in the current evidence regarding the use of ICE in PFA, building on evidence already established for radiofrequency ablation procedures. Full article

Percutaneous coronary intervention (PCI) is a widely performed revascularisation procedure for coronary artery disease. Although effective, its reliance on fluoroscopy and iodinated contrast exposes patients and operators to risks of radiation and nephrotoxicity. As PCI techniques have become more complex, interest has grown in imaging methods that reduce dependence on fluoroscopy and contrast. Electro-anatomical mapping systems (EAMS), developed for catheter navigation in electrophysiology, enable real-time three-dimensional visualisation without the need for fluoroscopy or contrast. By adapting coronary guidewires as electrodes, EAMS can reconstruct vessel anatomy and track interventional tools in real time. EAMS have demonstrated feasibility and safety in device implantation, and early studies suggest their applicability to PCI, where they may mitigate radiation and contrast exposure by providing an alternative method for guidewire and stent visualisation. This review provides a narrative overview of current evidence, outlining the technical principles, applications in device implantation, and the emerging role of EAMS in coronary intervention. Full article

Background/Objectives: For many years, catheter ablation (CA) has been a cornerstone in atrial fibrillation (AF) rhythm control therapy; however, recurrence remains common. Multiple parameters have been proposed to quantify AF arrhythmogenic substrate, yet reliable predictors of long-term outcomes are lacking. To assess the value of non-invasive amplified P-wave duration (PWD), echocardiographic parameters, biomarkers, and electroanatomical mapping (EAM) were used in predicting left atrial (LA) fibrosis and arrhythmia recurrence after CA. Methods: We included 196 patients undergoing first CA for paroxysmal or persistent AF. Amplified 12-lead ECG PWD parameters [Pmax, Pmin and left atrial P-wave (LAP)], echocardiographic parameters, and biomarkers were assessed pre-procedure. We measured low-voltage areas (LVA, 0.2–0.5 mV) on high-density voltage EAM during sinus rhythm as a surrogate of fibrosis. Freedom from arrhythmia was evaluated at 6 and 12 months. Results: Patients with LVA on EAM had prolonged Pmax (148 vs. 135 ms, p < 0.0001), Pmin (111 vs. 101.5 ms, p = 0.0001), LAP (73.5 vs. 55.5 ms, p < 0.0001), larger LA diameter (p = 0.0002), area (p = 0.0365) and volume (p = 0.004), higher E/E’ (p = 0.0007) and E/A ratios (p = 0.037), more mitral regurgitation (p = 0.0315), and higher pro-BNP levels (p = 0.0094). Univariate analysis showed 12-month recurrence rates higher with greater Pmax, Pmin, LAP, LVA presence and extent; however, in multivariate analysis, only P-wave parameters remained independently associated with recurrence. Conclusions: Prolonged PWD parameters strongly reflect LA substrate (Pmax, Pmin) and independently predict post-ablation AF recurrence (Pmax, Pmin, and LAP). LA size, diastolic dysfunction, and mitral regurgitation were associated with LA fibrosis, while pro-BNP was associated with both fibrosis and arrhythmia recurrence. Integrating these simple, non-invasive markers into a multimodal assessment alongside EAM could improve pre-procedural risk stratification and guide individualized ablation strategies. Full article