Incidence and predictors of thermal oesophageal and vagus nerve injuries in Ablation Index-guided high-power-short-duration ablation of atrial fibrillation: a prospective study.

AIMS: High-power-short-duration (HPSD) ablation is an effective treatment for atrial fibrillation but poses risks of thermal injuries to the oesophagus and vagus nerve. This study aims to investigate incidence and predictors of thermal injuries, employing machine learning. METHODS AND RESULTS: A prospective observational study was conducted at Leipzig Heart Centre, Germany, excluding patients with multiple prior ablations. All patients received Ablation Index-guided HPSD ablation and subsequent oesophagogastroduodenoscopy. A machine learning algorithm categorized ablation points by atrial location and analysed ablation data, including Ablation Index, focusing on the posterior wall. The study is registered in clinicaltrials.gov (NCT05709756). Between February 2021 and August 2023, 238 patients were enrolled, of whom 18 (7.6%; nine oesophagus, eight vagus nerve, one both) developed thermal injuries, including eight oesophageal erythemata, two ulcers, and no fistula. Higher mean force (15.8 ± 3.9 g vs. 13.6 ± 3.9 g, P = 0.022), ablation point quantity (61.50 ± 20.45 vs. 48.16 ± 19.60, P = 0.007), and total and maximum Ablation Index (24 114 ± 8765 vs. 18 894 ± 7863, P = 0.008; 499 ± 95 vs. 473 ± 44, P = 0.04, respectively) at the posterior wall, but not oesophagus location, correlated significantly with thermal injury occurrence. Patients with thermal injuries had significantly lower distances between left atrium and oesophagus (3.0 ± 1.5 mm vs. 4.4 ± 2.1 mm, P = 0.012) and smaller atrial surface areas (24.9 ± 6.5 cm2 vs. 29.5 ± 7.5 cm2, P = 0.032). CONCLUSION: The low thermal lesion's rate (7.6%) during Ablation Index-guided HPSD ablation for atrial fibrillation is noteworthy. Machine learning based ablation data analysis identified several potential predictors of thermal injuries. The correlation between machine learning output and injury development suggests the potential for a clinical tool to enhance procedural safety.

Coherent mapping of atrial tachycardias in patients with congenital heart disease.

AIMS: Coherent mapping (CM) uses a new algorithm to identify critical conduction isthmuses of atrial tachycardias (ATs). We analysed our experience of ablation of AT in patients with congenital heart disease (CHD) with this new technology. METHODS AND RESULTS: All patients with CHD who had CM of AT using the high-density mapping PENTARAY™ catheter and three-dimensional electroanatomic mapping system Carto3 between June 2019 and June 2021 were included retrospectively (n = 27). As a control group, 27 patients with CHD and mapping of AT without CM between March 2016 and June 2019 were included. In total, 54 ablation procedures were performed in 42 patients [median age 35 (interquartile range, IQR 30-48) years] and 64 ATs were induced and mapped (thereof 50 AT intraatrial re-entrant tachycardia and 14 AT ectopic AT). The median procedure duration was 180 (120-214) min and median fluoroscopy time was 10 (5.2-14) min. Acute success was 100% (27/27) in the Coherence group and 74% (20/27) in the non-Coherence group (P = 0.01). During follow-up [median 26 (12-45) months], AT recurred in 28/54 patients, thereof 15 patients needed a re-ablation procedure. Log-rank test showed no difference in recurrence rate between the two groups (P = 0.29). Three minor complications occurred (5.5%). CONCLUSION: Mapping of AT in patients with CHD using the PENTARAY™ mapping catheter and the CM algorithm led to excellent acute success. All ATs were possible to map and no complications related to the PENTARAY™ mapping catheter were observed. Thus, the use of the CM algorithm represents a promising tool in patients with CHD and complex AT.

Cardiac tamponade complicating ventricular arrhythmia ablation: Real life data on incidence, management, and outcome.

BACKGROUND AND OBJECTIVE: Cardiac tamponade during ablation procedures is a life-threatening complication. While the incidence and management of tamponade in atrial fibrillation ablation have been extensively described, the data on tamponade during ventricular ablations are very limited. The purpose of this study is to shed light on the incidence, typical perforation sites, and optimal management as observed through real-life data in a tertiary referral center for ventricular ablation. METHODS AND RESULTS: Consecutive patients with structural heart disease undergoing ventricular tachycardia ablation from 2008-2020 were analyzed. Of the 1078 patients undergoing 1287 ventricular ablation procedures, 20 procedures (1.5%) were complicated by cardiac tamponade. In all but one patient, the tamponade was treated with emergent pericardial drainage, while nine patients eventually underwent surgical repair. The perforation occurred during transseptal or subxiphoid puncture in six patients, during ventricle mapping in two patients, and during ablation in five patients (predominantly basal left ventricle). Steam pop as definite perforation cause could only be established in two patients. Regardless of the management of the complication, all patients survived to discharge. CONCLUSION: Cardiac tamponade during ventricular ablation occurred in 1.5% of the procedures. In nine patients cardiac repair was necessary. Perforation was mostly associated with subxiphoid puncture or ablation of the basal left ventricle.

Relevance of Chronic Total Occlusion for Outcome of Ventricular Tachycardia Ablation in Ischemic Cardiomyopathy.

Background: Catheter ablation of ventricular tachycardia (VT) in patients with ischemic cardiomyopathy (ICM) is an effective tool to prevent VT recurrences. Chronic total occlusion (CTO) represents a clinically relevant entity in ICM patients and is an independent predictor of ventricular arrhythmia and mortality. The effects of CTO on the outcome of VT ablation are not well-studied. Objective: This analysis aimed to identify the impact of CTO, revascularized, or not revascularized, on the outcome of VT ablation. Methods and Results: Of 385 consecutive subjects with ICM-VT who underwent catheter VT ablation for monomorphic VT at Heart Center Leipzig between 2008 and 2017, 108 patients without CTO and 191 patients with CTO were included in the analysis. Within a median follow-up time of 557 days (IQR 149, 1095), VT recurred in 77 (40%) patients in the CTO and 40 (37.0%) in the non-CTO cohort (p = 0.62). In a multivariable model, a 10% stepwise change in LVEF as well as ICD on admission was associated with VT recurrence (HRadj 1.82, 95% CI 1.04-3.18 and HRadj 1.35, 95% CI 1.23-1.61, respectively). Of the CTO cohort before ablation, 45% had received revascularization, which was independently associated with a higher risk for VT recurrence (HR 2.12, 95% CI 1.35-3.34) as compared to nonrevascularized CTO. Conclusion: In ICM patients with and without CTO, VT ablation was associated with equal effectiveness with regard to VT recurrence. However, in revascularized CTO patients, the risk of recurrence of VT after ablation was significantly increased.

Outcomes following cardiac sympathetic denervation in patients with structural heart disease and refractory ventricular arrhythmia.

AIM: Cardiac sympathetic denervation (CSD) has been introduced as a bailout therapy in patients with structural heart disease and refractory ventricular arrhythmias (VAs), but available data are scarce. Purpose of this study was to estimate immediate results, complications, and mid-term outcomes of CSD following recurrent VA after catheter ablation. METHODS AND RESULTS: Adult patients who underwent CSD in the Heart Center Leipzig from March 2017 to February 2021 were retrospectively analysed. Follow-up (FU) was executed via implantable cardioverter defibrillator (ICD) interrogation, telephone interviews, and reviewing medical records. Twenty-one patients (age 63.7 ± 14.4 years, all men, 71.4% non-ischaemic cardiomyopathy, left ventricular ejection fraction 31.6 ± 12.6%) received CSD via video-assisted thoracoscopic surgery (90.5% bilateral, 9.5% left-sided only). Indication for CSD was monomorphic ventricular tachycardia in 76.2% and ventricular fibrillation in 23.8 with 71.4% of patients presenting with electrical storm before index hospitalization. Procedure-related major complications occurred in 9.5% of patients. In-hospital adverse events not related to surgery were common (28.6%) and two patients died during the index hospital stay. During FU (mean duration 9.1 ± 6.5 months), five more patients died. Of the remaining patients, 38.5 and 76.9% were free from any VA or ICD shocks, respectively. CONCLUSIONS: The CSD showed additional moderate efficacy to suppress VAs, when performed as a bailout therapy after previously unsuccessful catheter ablation. At 9 months, it was associated with freedom of ICD shocks in two-thirds of patients. In a population with many comorbidities, the rate of CSD-related complications was acceptable, although there was an overall high risk of procedure unrelated adverse events and death.

A novel ECG finding in patients with epicardial infarct-associated ventricular tachycardia: a case series.

OBJECTIVES: This study analyzes the incidence, characteristics, and ECG morphology of ventricular tachycardia (VT) in post-infarction patients undergoing epicardial VT ablation. BACKGROUND: Ablation of recurrent VTs in patients with ischemic cardiomyopathy is typically performed endocardially. In rare cases, epicardial access is required to achieve non-inducibility. METHODS AND RESULTS: The study evaluated the baseline characteristics, procedural data, and ECG morphology of clinical VT in patients undergoing epicardial VT ablation. From the initial 491 patients with coronary heart disease (CHD) and recurrent VTs undergoing ablation at the Heart Center of Leipzig, Germany, between 2012 and 2020, only 39 patients required an additional epicardial access. In 17 patients, the VTs were associated with infarction scar, while the remaining patients had concomitant CHD without infarction-associated scar and were excluded from the analysis. A propensity match study was performed at a 1:2 ratio for these 17 patients, with 34 patients of the initial cohort as a control group to evaluate the differences in baseline characteristics, procedural data, and ECG morphology of the VTs. The specific VT morphology of negative concordance and superior axis in patients with inferior scar as well as the history of VT ablation were independent predictors of the need for epicardial access. CONCLUSIONS: In addition to previous endocardial ablation, VT ECG morphology with negative concordance and superior axis in post-infarction patients with inferior scar predicted the need for epicardial VT ablation.

[Catheter ablation of ventricular tachycardias in patients with ischemic cardiomyopathy]. / Katheterablation ventrikulärer Tachykardien bei Patienten mit ischämischer Kardiomyopathie.

Radiofrequency (RF) ablation is an effective treatment option of scar-related ventricular tachycardias (VT) in patients with ischemic cardiomyopathy. Several studies proved the benefit of VT catheter ablation, which has become routine in most electrophysiology laboratories. This article provides practical instructions to perform a VT catheter ablation. The authors describe conventional and substrate-based mapping and ablation strategies as well as concepts for image integration. This article continues a series of publications created for education in advanced electrophysiology.

[Practical guide for safe and efficient cryoballoon ablation for atrial fibrillation : Practical procedure, tips and tricks]. / Leitfaden zur sicheren und effizienten Kryoballon-Vorhofflimmerablation : Praktisches Vorgehen, Tipps und Tricks.

In the current guidelines on treatment of atrial fibrillation, cryoballoon-based catheter ablation of atrial fibrillation is recommended in addition to radiofrequency ablation and has become established as a standard procedure in the clinical routine of many centers for index pulmonary vein isolation. A safe, simplified and often durable pulmonary vein isolation can be achieved by a systematic approach. This review article provides a practical guide for all steps of cryoballoon-based pulmonary vein isolation, including preprocedural preparation and postinterventional follow-up. Both cryoballoon systems currently available on the market are considered.

LV Pseudoaneurysm With Concomitant Mitral Valve Defect After LV Summit Ablation: A Rare Late Complication.

A 25-year-old male patient with highly symptomatic, monomorphic, premature ventricular contractions presented for repeat ablation after failed endocardial ablation. Three weeks after excessive endocardial and epicardial ablation on the left ventricular summit, the patient was admitted again with tamponade following a pseudoaneurysm on the ablation site. (Level of Difficulty: Advanced.).

Gender differences in patients with structural heart disease undergoing VT ablation.

INTRODUCTION: This study sought to examine gender differences in patients with structural heart disease (SHD) referred for ablation of ventricular tachycardia (VT). BACKGROUND: Female patients are often underrepresented in large studies. Significant differences in the clinical presentation, treatment, and prognosis of female patients have been described in previous studies. METHODS AND RESULTS: We investigated 88 female patients with SHD undergoing VT ablation (mean age 59 years, 56% nonischemic cardiomyopathy, mean left ventricular ejection fraction 35%, 82% in electrical storm). A case-control study with 88 male patients was performed and the results regarding clinical and procedural characteristics, acute and long-term results of the two groups were compared. The female patients had more arrhythmogenic substrate, as they more commonly presented with electrical storm (p = .016) and had a higher number of inducible VT morphologies during the procedure (p = .018). Moreover, the female patients were less likely to have an optimized heart failure medical treatment at baseline (p = .030) and required more time from the first manifestation of the VT to ablation referral (p = .034). Although fewer epicardial ablations were performed in female patients (p = .019), the two groups showed similar results regarding VT noninducibility as ablation endpoint (p = .844), major procedure-related complications (p = .719) and freedom from VT during follow-up (p = .268). Moreover, the overall mortality in the two groups was similar (p = .176). Advanced NYHA class was associated with worse transplant and assist-device-free survival in the female group. CONCLUSION: Female patients presenting for VT ablation had more arrhythmogenic substrate and were less likely to have an optimized heart failure medical treatment. Nevertheless, the procedural acute and long-term outcomes between the two genders were similar.

Epicardial ablation of ventricular tachycardia in patients with structural heart disease: a single-centre experience over 12 years.

AIMS: Epicardial ablation has risen to an essential part of the treatment of ventricular tachycardias (VTs). In this study, we report the efficacy, risks, and current trends of epicardial ablation in structural heart disease as reported in a tertiary single centre over a 12-year period. METHODS AND RESULTS: Two hundred and thirty-six patients referred for VT ablation underwent a successful epicardial access and were included in the analysis (89% non-ischaemic cardiomyopathy, 90% males, mean age 60 years, mean left ventricular ejection fraction 38.4%). After performing epicardial ablation the clinical VTs were eliminated in 87% of the patients and 71% of the cohort achieved freedom from VT during 22-month follow-up. Twelve patients (5%) suffered major procedure-related complications. Until the end of follow-up 47 (20%) patients died, 9 (4%) underwent a left ventricular assist device implantation and 10 (4%) patients received a heart transplantation. Antiarrhythmic drugs at baseline and during follow-up were independent predictors of VT recurrence. Atrial fibrillation, renal dysfunction, worse New York Heart Association class, and antiarrhythmic drugs at follow-up were associated with worse survival in our cohort. CONCLUSION: In this large tertiary single-centre experience, percutaneous epicardial access was feasible in the large majority of the cohort with acceptably low complications rates. A combined endo-/epicardial approach resulted in 87% acute and 71% long-term success. Further studies are needed to clarify the role of routine combined endo-/epicardial ablation in these complex cardiomyopathies.

Role of assist device implantation and heart transplantation in the long-term outcome of patients with structural heart disease after catheter ablation of ventricular tachycardia.

INTRODUCTION: Ablation of ventricular tachycardias (VTs) in patients with structural heart disease (SHD) has been associated with advanced heart failure and poor survival. METHODS AND RESULTS: This matched case-control study sought to assess the difference in survival after left ventricular assist device (LVAD) implantation and/or heart transplantation (HTX) in SHD patients undergoing VT ablation. From the initial cohort of 309 SHD patients undergoing VT ablation (187 ischemic cardiomyopathy, mean age 64 ± 12 years, ejection fraction of 34 ± 13%), 15 patients received an LVAD and nine patients HTX after VT ablation during a follow-up period of 44 ± 33 months. Long-term survival after LVAD did not differ from the matched control group (p = 0.761), although the cause of lethal events was different. All post-HTX patients survived during follow-up. CONCLUSION: In this matched case-control study on patients with SHD undergoing VT ablation, patients that received LVAD implantation had similar survival compared to the control group after 4­year follow-up, while the patients with HTX had a significantly better outcome.

VT ablation in geriatric patients with structural heart disease: Should there still be an age limit?

INTRODUCTION: This study sought to examine the feasibility and outcome of ablation of ventricular tachycardias (VTs) in a contemporary cohort of geriatric patients with structural heart disease (SHD). BACKGROUND: Geriatric patients are often underrepresented in large studies. As frailty is becoming an increasing problem, we need to examine the best course of action for this population. METHODS AND RESULTS: We investigated 68 SHD-patients ≥ 75 years old undergoing VT-ablation (men 88%, ischemic cardiomyopathy 77%, electrical storm 72%, mean left ventricular ejection fraction 31%) and divided the cohort into two groups: 75-79 years old (n = 51) and ≥80 years old (n = 17). The two groups showed similar results regarding noninducibility as ablation endpoint (p = .693), major procedure-related complications (p = .488), and VT-recurrence (p = .882) during the 39-month follow-up. At the end of the follow-up, 10 patients in the octogenarian group (59%) versus 16 patients of the other group (31%) died. CONCLUSION: Geriatric patients with SHD including octogenarians showed similar results regarding procedural endpoints, freedom of VT, and major procedure-associated complications after VT-ablation. When ablation is indicated, age alone should not be an inhibiting factor to treat these patients.

Impact of electroanatomical mapping-guided lead implantation on procedural outcome of His bundle pacing.

AIMS: Conventional His bundle pacing (HBP) can be technically challenging and fluoroscopy-intense, particularly in patients with His-Purkinje conduction disease (HPCD). Three-dimensional electroanatomical mapping (EAM) facilitates non-fluoroscopic lead navigation and HB electrogram mapping. We sought to assess the procedural outcome of routine EAM-guided HBP compared with conventional HBP in a real-world population and evaluate the feasibility and safety of EAM-guided HBP in patients with HPCD. METHODS AND RESULTS: We included 58 consecutive patients (72 ± 13 years; 71% male) who underwent an attempt to conventional (EAM- group; n = 29) or EAM-guided (EAM+ group; n = 29) HBP between June 2019 and April 2020. The centre's learning curve was initially determined (n = 40 cases) to define the conventional control group and minimize outcome bias favouring EAM-guided HBP. His bundle pacing was successful in 26 patients (90%) in the EAM+ and 27 patients (93%) in the EAM- group (P = 0.64). The procedure time was 90 (73-135) and 110 (70-130) min, respectively (P = 0.89). The total fluoroscopy time [0.7 (0.5-1.4) vs. 3.3 (1.4-6.5) min; P < 0.001] and fluoroscopy dose [21.9 (9.1-47.7) vs. 78.6 (27.2-144.9) cGycm2; P = 0.001] were significantly lower in the EAM+ than EAM- group. There were no significant differences between groups in His capture threshold (1.2 ± 0.6 vs. 1.4 ± 1.0 V/1.0 ms; P = 0.33) and paced QRS duration (113 ± 15 vs. 113 ± 17 ms; P = 0.89). In patients with HPCD, paced QRS duration was similar in both groups (121 ± 15 vs. 123 ± 12 ms; P = 0.77). The bundle branch-block recruitment threshold tended to be lower in the EAM+ than EAM- group (1.3 ± 0.7 vs. 1.8 ± 1.2 V/1.0 ms; P = 0.31). No immediate procedure-related complications occurred. One patient (2%) experienced lead dislodgement during 4-week follow-up. CONCLUSION: Implementation of routine EAM-guided HBP lead implantation is feasible and safe in a real-world cohort of patients with and without HPCD and results in a tremendous reduction in radiation exposure without prolonging procedure time or increasing procedure-related complications.

Prediction of low-voltage areas using modified APPLE score.

AIMS: The presence of low-voltage areas (LVAs) in patients with atrial fibrillation (AF) reflects left atrial (LA) electroanatomical substrate, which is essential for individualized AF management. However, echocardiographic anteroposterior LA diameter included into previous LVAs prediction scores does not mirror LA size accurately and impaired left ventricular ejection fraction (LV-EF) is not directly associated with atrial myopathy. Therefore, we aimed to compare a modified (m)APPLE score, which included LA volume (LAV) and LA emptying fraction (LA-EF) with the regular APPLE score for the prediction of LVAs. METHODS AND RESULTS: In patients undergoing first AF catheter ablation, LVAs were determined peri-interventionally using high-density maps and defined as signal amplitude <0.5 mV. All patients underwent cardiovascular magnetic resonance imaging before intervention. The APPLE (one point for Age ≥ 65 years, Persistent AF, imPaired eGFR ≤ 60 mL/min/1.73 m2, LA diameter ≥ 43 mm, and LVEF < 50%) and (m)APPLE (last two variables changed by LAV ≥ 39 mL/m2, and LA-EF < 31%) scores were calculated at baseline. The study population included 219 patients [median age 65 (interquartile range 57-72) years, 41% females, 59% persistent AF, 25% LVAs]. Both scores were significantly associated with LVAs [OR 1.817, 95% CI 1.376-2.399 for APPLE and 2.288, 95% CI 1.650-3.172 for (m)APPLE]. Using receiver operating characteristic curves analysis, the (m)APPLE score [area under the curve (AUC) 0.779, 95% CI 0.702-0.855] showed better LVAs prediction than the APPLE score (AUC 0.704, 95% CI 0.623-0.784), however, without statistically significant difference (P = 0.233). CONCLUSION: The modified (m)APPLE score demonstrated good prognostic value for LVAs prediction and was comparable with the regular APPLE score.

Predictors of long-term mortality after catheter ablation of ventricular tachycardia in a contemporary cohort of patients with structural heart disease.

AIMS: Ablation of ventricular tachycardias (VTs) in patients with structural heart disease has been established in the past decades as an effective and safe treatment. However, the prognosis and long-term outcome remains poor. METHODS AND RESULTS: We investigated 309 patients with ischaemic cardiomyopathy (ICM) and non-ischaemic cardiomyopathy (NICM) (186 ICM, 123 NICM; 271 males; mean age 64.1 ± 12 years; ejection fraction 34 ± 13%) after ≥1 VT ablations over a mean follow-up period of 34 ± 28 months. Electrical storm was the indication for 224 patients (73%), whereas 86 patients (28%) underwent epicardial as well as endocardial ablation. During follow-up, 132 patients (43%) experienced VT recurrence and 97 (31%) died. Ischaemic cardiomyopathy and NICM patients showed comparable results, regarding procedural endpoints, complications, VT recurrence and survival. The Cox-regression analysis for all-cause mortality revealed that the presence of higher left ventricular end-diastolic volume (LVEDV; P < 0.001), male gender (P = 0.018), atrial fibrillation (AF; P < 0.001), chronic obstructive pulmonary disease (COPD; P = 0.001), antiarrhythmic drugs during the follow-up (P < 0.001), polymorphic VTs (P = 0.028), and periprocedural complications (P = 0.001) were independent predictors of mortality. CONCLUSION: Ischaemic cardiomyopathy and NICM patients undergoing VT ablation had comparable results regarding procedural endpoints, complications, VT recurrence and 3-year mortality. Higher LVEDV, male gender, COPD, AF, polymorphic VTs, use of antiarrhythmics, and periprocedural complications are strong and independent predictors for increased mortality. The PAINESD score accurately predicted the long-term outcome in our cohort.

Oesophageal Probe Evaluation in Radiofrequency Ablation of Atrial Fibrillation (OPERA): results from a prospective randomized trial.

AIMS: The aim of the study was to determine the incidence of oesophageal lesions after radiofrequency ablation (RFA) of atrial fibrillation (AF) with or without the use of oesophageal temperature probes. METHODS AND RESULTS: Two hundred patients were prospectively randomized into two groups: the OPERA+ group underwent RFA using oesophageal probes (SensiTherm™); the OPERA- group received RFA using fixed energy levels of 25 W at the posterior wall without an oesophageal probe. All patients underwent post-interventional endoscopy and Holter-electrocardiogram after 6 months. (Clinical.Trials.gov: NCT03246594). One hundred patients were randomized in OPERA+ and 100 patients in OPERA-. The drop-out rate was 10%. In total, 18/180 (10%) patients developed endoscopically diagnosed oesophageal lesions (EDEL). There was no difference between the groups with 10/90 (11%) EDEL in OPERA+ vs. 8/90 (9%) in OPERA- (P = 0.62). Despite the higher power delivered at the posterior wall in OPERA+ [28 ± 4 vs. 25 ± 2 W (P = 0.001)], the average EDEL size was equal [5.7 ± 2.6 vs. 4.5 ± 1.7 mm (P = 0.38)]. The peak temperature did not correlate with EDEL size. During follow-up, no patient died. Only one patient in OPERA- required a specific therapy for treatment of the lesion. Cumulative AF recurrence after 6 (3-13) months was 28/87 (32%) vs. 34/88 (39%), P = 0.541. CONCLUSION: This first randomized study demonstrates that intraoesophageal temperature monitoring using the SensiTherm™ probe does not affect the probability of developing EDEL. The peak temperature measured by the thermoprobe seems not to correlate with the incidence of EDEL. Empiric energy reduction at the posterior wall did not affect the efficacy of the procedure.