Pulsed field ablation (PFA) is an emerging technology for the treatment of atrial fibrillation (AF), for which pre-clinical and early-stage clinical data are suggestive of some degree of preferentiality to myocardial tissue ablation without damage to adjacent structures. Here in the MANIFEST-17K study we assessed the safety of PFA by studying the post-approval use of this treatment modality. Of the 116 centers performing post-approval PFA with a pentaspline catheter, data were received from 106 centers (91.4% participation) regarding 17,642 patients undergoing PFA (mean age 64, 34.7% female, 57.8% paroxysmal AF and 35.2% persistent AF). No esophageal complications, pulmonary vein stenosis or persistent phrenic palsy was reported (transient palsy was reported in 0.06% of patients; 11 of 17,642). Major complications, reported for ~1% of patients (173 of 17,642), were pericardial tamponade (0.36%; 63 of 17,642) and vascular events (0.30%; 53 of 17,642). Stroke was rare (0.12%; 22 of 17,642) and death was even rarer (0.03%; 5 of 17,642). Unexpected complications of PFA were coronary arterial spasm in 0.14% of patients (25 of 17,642) and hemolysis-related acute renal failure necessitating hemodialysis in 0.03% of patients (5 of 17,642). Taken together, these data indicate that PFA demonstrates a favorable safety profile by avoiding much of the collateral damage seen with conventional thermal ablation. PFA has the potential to be transformative for the management of patients with AF.

Background: Pulmonary vein isolation (PVI) has become the cornerstone treatment of atrial fibrillation (AF). While in cryoablation cell damage is caused by thermal effects, lately, pulsed field ablation (PFA) has been established as a novel non-thermal tissue-specific ablation modality for PVI. However, data comparing outcomes of patients undergoing either PFA or cryoballoon ablation (CBA) for primary PVI are sparse. Methods: Consecutive patients with AF undergoing PVI by either CBA or PFA were included in the analysis. The primary outcome was the time to AF/AT recurrence. For secondary outcomes, clinical and periprocedural parameters were compared. Results: In total, outcomes of 141 AF patients treated by PFA (94 patients) or CBA (47 patients) were compared. After 365 days, 70% of patients in the PFA group and 61% of patients in the CBA group were free from AF/AT (HR 1.35, 95% CI 0.60–3.00; p = 0.470). No deaths occurred. While symptoms alleviated in both groups, only after PFA, we observed significant improvement of left atrial volume index (PFA group baseline: 40 [31;62] ml/m², PFA group follow-up: 35 [29;49] ml/m²; p = 0.015), NT-pro BNP levels (PFA group baseline: 1106 ± 2479 pg/ml, PFA group follow-up: 1033 ± 1742 pg/ml; p = 0.048), and left ventricular ejection fraction (LVEF) (PFA group baseline: 55 [48;60] %, PFA group follow-up: 58 [54;63] %; p = 0.006). PVI by PFA was the only independent predictor of LVEF improvement. Conclusion: In our study, we show that CBA and PFA for PVI are of similar efficacy when it comes to AF recurrence. However, our findings suggest that PFA rather than CBA might induce left atrial reverse remodeling thereby contributing to left ventricular systolic function.

Aims: Catheter ablation of ventricular arrhythmias (VA) has proven to be an effective therapeutic option for secondary arrhythmia prophylaxis. We sought to assess the procedural efficacy, safety and in-hospital mortality of a large patient cohort with and without structural heart disease undergoing VA ablation. Methods: A total of 1417 patients (804 patients with structural heart disease) undergoing 1792 endo- and epicardial procedures were analyzed. Multivariable risk factor analysis for occurrence of major complications and intrahospital mortality was obtained and a score to allow preprocedural risk assessment for patients undergoing VA ablation procedures was established. Results: Major complication occurred in 4.4% of all procedures and significantly more often in patients with structural heart disease than in structurally normal hearts (6.0 vs. 1.8%). The frequency of these periprocedural complications was significantly different between procedures with sole right ventricular and a combination of RV and LV access (0.5 vs. 3.1%). The most common complication was cardiac tamponade in 46 cases (3.0%). Intrahospital death was observed in 32 patients (1.8%). Logistic regression model revealed presence of ischemic heart disease, epicardial ablation, presence of oral anticoagulation or dual antiplatelet therapy as independent risk factors for the occurrence of complications or intrahospital death, while a history of previous heart surgery was an independent predictor with a decreased risk. Based on this analysis a risk score incorporating 5 standard variables was established to predict the occurrence of complications and intrahospital mortality. Conclusions: Safety of VA catheter ablation mainly relies on patient baseline characteristics and the type of access into the ventricles or epicardial space.

Introduction: Pericardial access for ablation of ventricular arrhythmias (VA) can be gained either by an anterior-oriented or inferior-oriented epicardial puncture under fluoroscopical guidance. We retrospectively sought to assess the safety of these two puncture techniques and the incidence of epicardial adhesions and introduce our algorithm for management of pericardial tamponade. Methods and results: In 211 patients (61.4 ± 15.6 years, 179 males; 84.8%) 271 epicardial ablation procedures of VA were performed using either an anterior- or inferior-oriented approach for epicardial access. Puncture-related complications were systematically analyzed. Furthermore, the incidence of adhesions was evaluated during first and repeated procedures. A total of 34/271 (12.5%) major complications occurred and 23/271 (8.5%) were directly related to epicardial puncture. The incidence of puncture-related major complications in the anterior and inferior group was 4/82 (4.9%) and 19/189 (10.1%), respectively. Pericardial tamponade was the most common major complication (15/271; 5.5%). Collateral damages of adjacent structures such as liver, colon, gastric vessels and coronary arteries occurred in 6/189 (3.2%) patients and only within the inferior epicardial access group. Adhesions were documented in 19/211 (9%) patients during the first procedure and in 47.1% if patients had 2 or more procedures involving epicardial access. Conclusion: Anterior-oriented epicardial puncture shows an observed association to a reduced incidence of pericardial tamponades and overall puncture-related complications in epicardial ablation of VA. In cases of repeated epicardial access adhesions increase significantly and may lead to ablation failure.

Aims: The aim of this study was to analyse tamponades following electrophysiological procedures regarding frequency and mortality in a high-volume centre and to identify independent predictors for severe tamponades. Methods and results: We performed a retrospective study on 34 982 consecutive patients undergoing diagnostic electrophysiological studies or catheter ablation of cardiac arrhythmias. The combined endpoint was defined as severe tamponade. Criteria for severe tamponade included surgical repair, repeat pericardiocentesis, cardiopulmonary resuscitation, intrahospital death or death during follow-up, and thrombo-embolic events or complications due to therapeutic management. Multivariate analysis was performed to identify independent predictors for severe tamponade. A total of 226 tamponades were identified. Overall frequency of tamponades was 0.6%. Procedures requiring epicardial approach had the highest rate of tamponades (9.4%). Twenty-nine patients with tamponade underwent surgery (12.8% of all tamponades and 21.4% of tamponades during epicardial procedures). Overall tamponade-related mortality was 0.03% (9 deaths). Fifty-six patients (24.8%) experienced severe tamponade. Independent risk factors for severe tamponades were endocardial ablation of ventricular tachycardia, epicardial approach, balloon device ablation, high aspiration volume during pericardiocentesis and structural heart disease. Conclusion: The frequency of tamponades is strongly dependent on the type of procedure performed. Overall tamponade-related mortality was low but significantly higher in patients undergoing epicardial procedures. Surgical backup should be considered for patients undergoing complex ventricular tachycardia ablation and left atrial ablation procedures.