Search Results (192)

Background: The influence of the initial ablation modality on pulmonary vein (PV) reconnection and substrate characteristics in redo procedures for recurrent atrial fibrillation (AF) remains unclear. We assessed how different thermal strategies—ablation index (AI)-guided radiofrequency (RF) versus cryoballoon (CB) ablation—affect remapping findings during redo pulmonary vein isolation (PVI). Methods: We included patients undergoing redo ablation between 2015 and 2024 with high-density electroanatomic mapping. Initial PVI modalities were retrospectively classified as low-power, long-duration (LPLD) RF; high-power, short-duration (HPSD) RF; or second-/third-generation CB. Reconnection sites were mapped using multielectrode catheters. Redo PVI was performed using AI-guided RF. Segments showing PV reconnection were reisolated; if all PVs remained isolated and AF persisted, posterior wall isolation was performed. Results: Among 195 patients (LPLD: 63; HPSD: 30; CB: 102), complete PVI at redo was observed in 0% (LPLD), 23.3% (HPSD), and 10.1% (CB) (p < 0.01 for LPLD vs. HPSD). Reconnection patterns varied by technique; LPLD primarily affected the right carina, while HPSD and CB showed reconnections at the LSPV ridge. Organized atrial tachycardia was least frequent after CB (12.7%, p < 0.002). Conclusion: Initial ablation strategy significantly influences PV reconnection and post-PVI arrhythmia patterns, with implications for redo procedure planning. Full article

Background/Objectives: Pulmonary vein isolation (PVI) via cryoballoon ablation (CBA) is a recommended therapeutic strategy for patients with symptomatic paroxysmal and persistent atrial fibrillation (AF) who are refractory to antiarrhythmic drugs. Although PVI has demonstrated efficacy in reducing AF recurrence and improving patients’ quality of life, its impact on respiratory function is not well understood, particularly in patients with comorbid conditions. The aim of the study was to search for functional predictors of the respiratory system in the process of evaluating the efficiency of clinical assessment of CBA in patients with AF. Methods: We conducted a prospective study on 42 patients with symptomatic AF who underwent CBA, assessing their respiratory function through spirometry before and 30 days after the procedure. Exclusion criteria included pre-existing lung disease and cardiac insufficiency. The impact of variables such as body mass index (BMI), coronary artery disease (CAD) and heart failure (HF) on spirometry parameters was analyzed using statistical tests. Results: No significant changes were observed in overall post-PVI spirometry parameters for the full cohort. However, post hoc analyses revealed a significant decline in ΔMEF₇₅ in patients with CAD and BMI ≥ 30 kg/m², whereas ΔFEV₁/FVCex was significantly increased in patients with HF, as well as in patients with ejection fraction (EF) < 50%. Conclusions: CBA for AF does not universally affect respiratory function in the short term, but specific subgroups, including patients with CAD and a higher BMI, may require post-procedure respiratory monitoring. In addition, PVI may improve lung function in patients with HF and reduced EF. Full article

Background: Pulsed field ablation (PFA) is a novel non-thermal modality for pulmonary vein isolation (PVI) in atrial fibrillation (AF), offering myocardial selectivity through irreversible electroporation while sparing surrounding structures. However, concerns have emerged regarding potential subclinical hemolysis, reflected by alterations in biochemical markers such as lactate dehydrogenase (LDH). Methods: We conducted a retrospective, single-center study involving 249 patients undergoing PVI: 121 treated with PFA (PulseSelect or FARAPULSE) and 128 with radiofrequency (RF) ablation (PVAC catheter). Laboratory parameters were assessed at baseline, post-procedure, and at discharge, including hemoglobin, hematocrit, red blood cell (RBC) count, platelet count, creatinine, and LDH. The primary endpoint was the variation in blood cell indices; the secondary endpoint was the evaluation of LDH and hematocrit changes. Statistical analysis included t-tests and chi-square tests. Results: Baseline characteristics and pre-procedural labs did not differ significantly between groups. No significant changes in hemoglobin, hematocrit, RBC count, platelet count, or creatinine were observed post-ablation or at discharge. However, LDH levels significantly increased in the PFA group both post-procedurally and at discharge (p < 0.001), without concurrent changes in other blood cell parameters. Conclusions: PFA and RF ablation yield comparable hematological profiles after PVI, with no significant impact on key blood cell parameters. Nonetheless, the consistent rise in LDH levels in the PFA group suggests mild, subclinical hemolysis or tissue injury due to more extensive lesions. While supporting the hematologic safety of PFA, these findings underscore the need for further studies to assess the clinical significance of these biochemical alterations, particularly in high-risk patients or extensive ablation settings. Full article

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation, especially effective in patients with paroxysmal AF, where the pulmonary veins (PVs) are the primary triggers. More complex arrhythmogenic mechanisms are involved in persistent AF (PsAF), and PVI alone may not be sufficient. Personalized, substrate-based ablation strategies are increasingly used and can significantly enhance outcomes in PsAF patients. While radiofrequency ablation remains the gold standard, cryoablation provides effective PVI, and pulsed field ablation is emerging as a safer, promising alternative. Advanced mapping techniques may better target scar areas responsible for arrhythmogenesis, optimizing procedural results. While still in development, artificial intelligence and machine learning enable more personalized and precise ablation strategies and may improve long-term outcomes. Full article

Background: Epicardial adipose tissue (EAT) may contribute to the pathogenesis of atrial fibrillation (AF). The attenuation of EAT assessed by means of computed tomography (CT) may reflect the severity of local tissue inflammation. This study aimed to systematically analyze the relationship between the attenuation of EAT surrounding the left atrium (LA-EAT) and AF recurrence after catheter ablation (CA). Methods: Five databases were searched up to April 10, 2025. Original studies involving adult patients with paroxysmal or persistent AF undergoing CA were included if they provided quantitative measurements of LA-EAT attenuation on cardiac CT before ablation. Results: A total of seven retrospective observational studies with 2440 patients were included in the analysis. The percentage of male participants ranged from 60.9% to 73.0%, and the mean or median age of patients varied from 57.5 to 68.2 years. The mean body mass index across studies ranged from 24.0 to 32.4 kg/m². A pooled analysis of all included trials demonstrated that the mean LA-EAT attenuation in the AF recurrence group was −78.97 ± 15.34 HU, which was less negative compared to the non-recurrence group (−81.37 ± 15.46 HU; mean difference [MD] = 2.22; 95% confidence interval [CI]: 0.84 to 3.61; p = 0.002). Conclusions: LA-EAT attenuation is significantly more positive in patients experiencing AF recurrence compared to those without recurrence following CA procedures. Full article

Background: Atypical atrial flutter (AFL) is a complex clinical challenge, particularly in patients with prior atrial fibrillation (AF) treated with pulmonary vein isolation (PVI). Arrhythmias involving the vein of Marshall (VOM) often require extensive lesion sets, including ethanol infusion, to effectively target the epicardial substrate. To minimize tissue damage, an alternative strategy has been proposed, emphasizing advanced electroanatomical mapping, entrainment maneuvers, and highly targeted ablation techniques. Case Presentation: We describe a 72-year-old woman with recurrent atrial arrhythmias following pulmonary vein isolation (PVI), who presented with palpitations as her primary symptom. After ineffective pharmacological therapy, she underwent a catheter ablation procedure. Electroanatomical mapping revealed significant left atrial scarring and suggested a macroreentrant circuit involving the VOM. Entrainment maneuvers confirmed the VOM’s involvement. A single targeted endocardial ablation guided by the ablation index terminated the arrhythmia within 12 s, without the need for ethanol infusion or extensive lesion sets. Discussion: This case underscores the VOM’s role in sustaining atypical AFL post-PVI and highlights the effectiveness of precise electroanatomical mapping combined with targeted endocardial ablation. Unlike broader ablation or ethanol infusion strategies, a focused lesion at the critical isthmus achieved arrhythmia termination with minimal tissue damage. Conclusions: Endocardial ablation at the site of entrainment can safely and effectively treat VOM-related AFL, offering symptom relief and restoration of sinus rhythm. This approach may reduce procedural risks and expand the feasibility of VOM-related arrhythmia management in centers without access to ethanol infusion. Full article

Background: Pulsed field ablation (PFA) is a safe and effective method for pulmonary vein isolation (PVI) in atrial fibrillation (AF) patients. However, most first-generation PFA catheters are not integrated with 3D mapping systems, requiring fluoroscopy for guidance. The use of X-ray technologies, however, poses significant health risks to both patients and operating staff. Recently, a new variable-loop PFA catheter (VLC) with full 3D mapping integration allows for a novel fluoroscopy-free approach to PVI. In that regard, the aim was to evaluate and optimize a zero-fluoroscopy workflow for PVI using the VLC. Methods: Two workflows were described and compared: a conventional zero-fluoroscopy approach using a complete 3D left atrial map before ablation, and an optimized ‘mapping-on-the-fly’ approach that combines mapping and ablation into a continuous, real-time process for each pulmonary vein rather than performing them sequentially. Results: Forty-one pulmonary veins were successfully treated without fluoroscopy in 10 patients (20% female, median age 61 [IQR 55.5–66.8] years). Three patients underwent the conventional workflow, while seven received the optimized workflow. The ‘mapping-on-the-fly’ approach significantly reduced procedural time (median 68 vs. 144 min, p = 0.017) and left atrial dwell time (46 vs. 107 min, p = 0.016). No fluoroscopy-related complications occurred. Conclusions: PVI using the fully 3D-integrated VLC can be safely and efficiently performed without fluoroscopy. The optimized ‘mapping-on-the-fly’ workflow improves procedural efficiency. Full article

Background: Inflammation plays an important role in the initiation of atrial fibrillation (AF) and the development of fibrosis following pulmonary vein isolation (PVI). We aimed to investigate whether early post-PVI levels of C-reactive protein (CRP), white blood cells, tumour necrosis factor alpha (TNF-α) and transforming growth factor beta 1 (TGF-ß1) are associated with long-term arrhythmia recurrence. Methods: This prospective observational study included 48 patients with paroxysmal AF undergoing PVI. Peripheral venous blood samples were collected on the day of hospitalisation (T0), immediately after the procedure (T1) and after 24 h (T2), seven days (T3) and one month (T4) following the procedure. Blood samples were obtained from the coronary sinus (CS) before and after PVI. CRP levels, leukocyte (LKc) and neutrophile (Neu) counts were determined. TGF-β1 and TNF-α were analysed using the enzyme-linked immunosorbent assay (ELISA). After discharge, follow-up visits were scheduled at seven days and one-, three-, six-, nine- and twelve-months post-ablation, with 24 h Holter monitoring at each visit. Results: Patients were allocated into a recurrent and a non-recurrent group. Baseline characteristics did not differ between the groups, except for the duration of AF, which was found to be a significant arrhythmia recurrence predictor. Patients in the non-recurrent group had statistically significantly higher LKc at all time points, and Neu at T2 and T3. CRP and TGF-β1 concentrations were significantly higher in the non-recurrent group, while TNF-α concentration was significantly higher in the recurrent group at the T2 time point. Significantly higher concentrations of CS TNF-α at T1 and TGF-β1 at T0 and T1 were documented in the non-recurrent group. Conclusions: The study shows that an enhanced inflammatory response early after PVI, characterised by increased CRP, WBC and TGF-β1 levels, may play a protective role against late arrhythmia recurrence. Full article

Background/Objectives: Left atrial diverticula (LADs) have been reported to potentially be associated with arrhythmic substrates, thromboembolic events, and complications during catheter ablation for atrial fibrillation (AF), but their clinical significance remains unclear. This study aimed to assess the prevalence, location, and potential relationship with complications during AF catheter ablation using preoperative CT. Methods: This study included 595 consecutive patients undergoing AF catheter ablation at Keio University Hospital from April 2021 to February 2024. Preoperative ECG-gated cardiac MDCT scans were analyzed to assess the presence and location of the LAD. Intraoperative adverse events were documented, and the association between the LAD and mechanical complications, such as a cardiac perforation and tamponade, was evaluated. Results: A total of 595 patients undergoing catheter ablation for AF or atrial tachycardia (AT) were included, with 210 (35.3%) found to have an LAD. No significant differences in age, sex, body mass index, or arrhythmia type were observed between patients with or without an LAD. LADs were most commonly located in the anterior region of the right superior pulmonary vein (53.4% of cases), followed by the anterior region of the left superior pulmonary vein (15% of cases). Perioperative complications occurred in 12 cases (2.0%), with 7 in the LAD group and 5 in the non-LAD group. Mechanical complications were observed exclusively in the LAD group (n = 4), with three of the cases associated with LADs. In all cases, LADs were present in the anterior region of the right superior pulmonary vein and were caused by the accidental insertion of an angiographic catheter into the LAD during pulmonary venography before insertion of the ablation catheter into the left atrium. However, all cases were hemodynamically stable, and the procedures were completed as planned. Conclusions: LADs are a more common anatomical structure than generally recognized and may be associated with mechanical complications during AF catheter ablation. Identifying the presence of an LAD on preoperative CT is crucial for predicting potential risks. Full article

Background: Atrial flutter (AFL) is a macro-reentrant tachycardia classified as cavotricuspid isthmus (CTI)-dependent or non-CTI-dependent based on its reliance on the CTI for conduction. CTI dependence can present as type I ECG (sawtooth flutter waves in inferior leads and positive P-waves in V1) or type II ECG (absence of these characteristics). This study aimed to identify clinical and electrophysiological parameters to improve CTI dependence prediction in AFL. Methods: Patients at the Ulm University Heart Center between 2010 and 2019 with AFL undergoing electrophysiological studies and ablation were enrolled. Clinical and electrophysiological parameters such as age, gender, prior comorbidities, interventions, and medication use were analyzed. Results: The study included 383 patients, with 70% presenting with type I ECG AFL. CTI dependence was observed in 242 (90.3%) type I ECG patients and 52 (45.2%) type II ECG patients. CTI-dependent AFL patients were younger and had fewer comorbidities. Predictors for CTI dependence in type I ECG included male gender (p = 0.006), absence of beta-blocker use (p = 0.031), no prior atrial fibrillation (p = 0.035), and no prior pulmonary vein isolation (p < 0.001). In type II ECG, predictors for CTI dependence included younger age (p = 0.016), male gender (p = 0.007), absence of arterial hypertension (p = 0.036), and longer atrial cycle length (p < 0.001). Conclusions: Identifying clinical and electrophysiological parameters enhances the ability to predict CTI dependence in AFL, offering valuable insights for tailored diagnostic and therapeutic approaches. Coupling these parameters with ECG findings holds promise for refining prediction accuracy and optimizing patient care. Full article

Objectives: Atrial fibrillation (AF) is the most common sustained arrhythmia associated with stroke, heart failure, and increased mortality. Due to its efficacy and safety, cryoballoon ablation (CBA) is widely accepted for rhythm control; however, long-term AF recurrence remains a challenge. Continuous monitoring with implantable loop recorders (ILRs) enhanced by artificial intelligence (AI) can detect both symptomatic and asymptomatic episodes, potentially optimizing patient management. This analysis assessed the long-term effectiveness of CBA in maintaining sinus rhythm and investigated the role of ILR-guided monitoring in enhancing therapeutic decisions. Methods: Data from 91 patients with paroxysmal or persistent atrial fibrillation (AF) who underwent pulmonary vein isolation using cryoballoon ablation at four Italian centers between April 2022 and April 2024 were analyzed. All patients received an insertable loop recorder (ILR) before or during hospitalization for ablation, allowing for the continuous remote monitoring of arrhythmias. Baseline demographics, procedural details, AF occurrence, AF burden (calculated as the total duration of all AF episodes occurring within a day and categorized by episode duration), therapeutic adjustments, and the effect of artificial intelligence (AI) on data processing were evaluated. Results: The cohort’s average age was 62.4 years, with 24.2% of participants being female. Physician-confirmed AF recurrence was noted in 26.7% of patients at 12 months and 49.5% at 24 months. The device data indicated a daily AF burden of ≥6 min in 47.2% at 12 months, with 25.9% surpassing 1 h. AI algorithms decreased false-positive alerts by 21%, resulting in an estimated saving of 19 clinician hours. In patients with pre-ablation ILR data, the median AF burden significantly decreased from 7% to 0.2% (p = 0.017). ILR-guided monitoring affected treatment adjustments, leading to the discontinuation of antiarrhythmic therapy in 36 patients and redo ablations in 8. Conclusions: Continuous ILR monitoring, combined with AI-driven analysis, enables the detection of AF recurrences and burden, thereby facilitating timely therapeutic adjustments. Full article

Catheter ablation (CA) was found to outperform antiarrhythmic drug therapy (AAD), and it is a key treatment for rhythm control for patients with symptomatic atrial fibrillation (AF). Nevertheless, the procedure’s effectiveness is limited by recurrence rates. Identifying determinants of effective ablation is critical for optimizing patient selection, operative results, and long-term rhythm management strategies. In this state-of-the-art review, we have comprehensively discussed the various factors that can determine the recurrence of AF after a successful CA. Full article

Atrial fibrillation (Afib) recurrence after catheter ablation (CA) remains a significant clinical challenge, driven by a complex and dynamic interplay of structural, electrical, and autonomic mechanisms. While pulmonary vein isolation (PVI) is the cornerstone of CA, recurrence rates remain substantial, highlighting the need to understand the evolving pathophysiology beyond PV reconnection. Post-ablation changes, including inflammation, edema, oxidative stress, and ischemia, create a transient proarrhythmic state that may contribute to early recurrence. Over time, atrial remodeling, fibrosis, and residual autonomic activity further sustain arrhythmogenicity. Additionally, epicardial adipose tissue promotes atrial myopathy, accelerating disease progression, particularly in patients with risk factors such as older age, female sex, obesity, hypertension, obstructive sleep apnea, and heart failure. The multifactorial nature of Afib recurrence underscores the limitations of a “one-size-fits-all” ablation strategy. Instead, a patient-specific approach integrating advanced mapping techniques, multimodal imaging, and computational modeling is essential. Artificial intelligence (AI) and digital twin models hold promise for predicting recurrence by simulating individualized disease progression and optimizing ablation strategies. However, challenges remain regarding the standardization and validation of these novel approaches. A deeper understanding of the dynamic interconnections between the mechanisms driving recurrence is crucial for improving long-term CA outcomes. This review explores the evolving nature of Afib recurrence, emphasizing the need for a precision medicine approach that accounts for the continuous interaction of pathophysiological processes in order to refine patient selection, ablation strategies, and post-procedural management. Full article

(1) Objective: To examine the efficiency and efficacy of using endovascular mapping and pulsed field ablation in the setting of a hybrid video-assisted thoracoscopic atrial fibrillation (AF) ablation procedure. (2) Methods: Eleven consecutive patients underwent hybrid video-assisted thoracoscopic epicardial ablation and left atrial appendage exclusion followed by endocardial ablation using pulsed field ablation energy. The completeness of epicardial and endocardial lesion sets were assessed using 3D electro-anatomical mapping. (3) Results: Left atrial appendage (LAA) exclusion and durable pulmonary vein isolation (PVI) and posterior wall isolation (PWI) were achieved in all patients. The endovascular part of the necessary lesion set using PFA energy was successful in 100% of the patients. All patients remained in SR during the 12-month follow-up period. (4) Conclusions: Our study confirms the feasibility of using endovascular pulsed field ablation to complete previously performed epicardial lesion sets during the hybrid AF ablation procedures, without extending the procedure time or increasing the risk of complications. Full article

Background/Objectives: Pulmonary vein isolation (PVI) is the cornerstone in the treatment of atrial fibrillation (AF). Despite initially successful PVI patients experience recurrence of AF potentially due to reconnection of pulmonary veins (PVs). However, a certain number of patients present with recurrent AF, despite durable PVI. The optimal ablation strategy for these patients has yet to be discerned. The aim of this study was to compare outcomes for different ablation strategies for recurrent AF despite persistent PVI. Methods: All redo procedures for the recurrence of atrial fibrillation from March 2018–May 2023 were analyzed. Only patients with proven durable PVI (entrance/exit block and high density (HD) mapping) who received linear ablation or CFAE (complex fractionated atrial electrogram)/low-voltage area ablation were included. Patients were excluded if re-PVI or ablation of atrial tachycardia (AT) was necessary. In all procedures, a 3D-HD map and radiofrequency ablation (RFA) were performed. The ablation strategy was at the operators’ discretion. Data from a routinely performed 12-month follow-up were obtained. Results: A total of 847 repeat ablation procedures for atrial arrhythmias were analyzed. In 170 (20.1%) procedures, all PVs were still isolated. Of these, 51 (30.0%) patients were excluded due to AT or because they did not receive further left atrial linear ablation or substrate modification. In total, 119 patients were included in the final analysis, and 71 out of 119 patients (59.7%) were male. The majority (89 patients, 74.8%) suffered from persistent AF. In 72 patients (60.5%), LA-scar (voltage < 0.4 mV) was detectable (81.9% persAF). The ablation strategies were either linear ablation (n = 55), a non-linear substrate modification strategy (CFAE ablation/ablation of low-voltage areas, n = 21) or a combination of both (n = 43). In the Kaplan–Meier analysis, none of the ablation strategies showed a significantly superior outcome. After 370.0 ± 144.9 days, 56.0% (48.1% vs. 61.9% vs. 62.8%, p = 0.3) were free from any arrhythmia. 15.4% vs. 9.5% vs. 9.3% developed an AT (p = 0.3). Left atrial dilatation correlated with recurrence of AF. Conclusions: In patients suffering from a recurrence of AF despite durable pulmonary vein isolation, different substrate modification strategies did not show any superiority for one or the other. Despite the necessity of additional ablation beyond PVI, the optimal ablation strategy has yet to be determined to improve the outcome of redo procedures. Full article