Gábor Orbán

Aims: Point-by-point radiofrequency catheter ablation is commonly used for pulmonary vein isolation (PVI) in atrial fibrillation (AF). Very high power short duration (vHPSD) technology offers similar efficacy to high power short duration (HPSD) with reduced procedure times. A major complication of thermal ablation is atrio-oesophageal fistula (AEF), with oesophageal lesions and gastroparesis indicating increased risk. A direct comparison of HPSD and vHPSD regarding thermal safety is lacking. This randomized, single-centre study aimed to compare the thermal safety of vHPSD to HPSD and identify anatomical and biophysical predictors of thermal injury (ClinicalTrials.gov ID: NCT06617442). Methods and results: Patients undergoing first-time PVI for AF were randomized to either HPSD (50 W) or vHPSD (90 W). The study followed a non-inferiority design, with the primary endpoint being a composite of oesophageal mucosal lesion and gastroparesis, assessed via endoscopy within 15 days post-procedure. Pre-procedural computed tomography scans were analysed for anatomical risk factors. Among 100 patients (50 per group), the primary endpoint occurred in 7 (14%) of the vHPSD group and 6 (12%) of the HPSD group (estimated mean difference −2%, lower bound of one-sided 95% CI −0.13), confirming non-inferiority. A smaller inter-lesion distance on the posterior wall was associated with increased risk (3.76 mm vs. 4.16 mm, P = 0.042). Conclusion: Pulmonary vein isolation using 90 W (vHPSD) applications was non-inferior to the 50 W (HPSD) power setting in terms of oesophageal safety. A smaller inter-lesion distance on the posterior wall was predictive of oesophageal injury.

Background: Mineralocorticoid receptor antagonists (MRAs) are core therapy in chronic heart failure (HF) and reduce all-cause mortality and sudden cardiac death. However, direct comparisons of spironolactone and eplerenone in the context of ventricular arrhythmia recurrence are lacking. This study aims to compare the effects of these two MRAs on all-cause mortality and recurrence of sustained monomorphic ventricular tachycardia (VT) in patients with HF. Methods: We analysed data of HF patients with left ventricular ejection fraction (LVEF) below 50%, hospitalised for sustained monomorphic VT and receiving MRA therapy at discharge. We performed propensity score matching for 13 variables, including medical history, medication and arrhythmia presentation. The endpoints were all‐cause mortality and VT recurrence. Results: Among the 292 patients who met the selection criteria, 202 were included in the final analysis after propensity score matching, representing 69% of the eligible cohort. Median age was 67 (61–74) years and 87% were male. The median LVEF was 30% (25%–35%). The median follow‐up duration was 32 (18–36) months, with a minimum follow‐up of 1 year. During follow-up, 70 patients died, while VT recurrence was observed in 86 patients. There was no significant difference in all-cause mortality between the two MRAs (HR 0.98 (0.62 to 1.57), p=0.94). However, eplerenone was associated with a significantly lower risk of VT recurrence compared with spironolactone (HR 0.42 (0.26 to 0.66), p<0.001, Fine-Gray adjusted HR 0.36 (0.22 to 0.59), p<0.001). Conclusions: In HF patients with sustained monomorphic VT, eplerenone was associated with fewer VT recurrences than spironolactone, without differences in all-cause mortality.

Aims: We hypothesize that sinus rhythm (SR) maintenance in persistent atrial fibrillation (AF) patients taking anti-arrhythmic drugs (AADs) after pre-procedural electrical cardioversion (ECV) could predict outcomes after catheter ablation procedures. Methods and results: 219 persistent AF patients on AADs underwent ECV 1–6 months before ablation. Patients were categorized into two groups according to their response to ECV: patients in whom SR was restored and maintained until the ablation procedure (ECV-SR group), and patients with AF recurrence before the procedure (ECV-AF group). Then, 1:1 propensity score matching was used to create study groups (94–94 patients). The efficacy outcomes of the present study were freedom from atrial tachyarrhythmia on/off AADs following a single ablation procedure and recurrence of persistent AF. The median follow-up duration was 42 (20–73) months. Freedom from atrial tachyarrhythmia at 36 months was lower in the ECV-AF group compared to ECV-SR patients (31.4% vs. 51.2%, respectively; crude HR = 2.58, 95% CI = 1.58–3.70, P < 0.001). The most frequent pattern of atrial arrhythmia recurrence was persistent AF in the ECV-AF group and paroxysmal AF in the ECV-SR group. Freedom from persistent AF at 36 months was 54% and 84.3%, respectively (crude HR = 3.72, 95% CI = 1.94–7.14, P < 0.001). Differences in the risk of the efficacy outcomes were similar after multi-variable adjustment and in all analysed subgroups, including pulmonary vein isolation (PVI)-only procedures. Conclusion: Our findings indicate that the positive response to pre-procedural ECV may be a valuable marker for identifying persistent AF patients in whom a PVI-only strategy is sufficient.

Introduction Catheter ablation using pulsed-field energy may penetrate deeper into scarred tissue than thermal energies; however, evidence regarding its role in treating ventricular arrhythmias (VA) is limited. In this prospective study, we report our current experience on pulsed-field ablation (PFA) with pentaspline catheter for the treatment of premature ventricular contractions (PVC) originating from the right ventricular outflow tract (RVOT) and scar-related ventricular tachycardias (VT). Methods Consecutive VA patients who underwent PFA with Farapulse system were enrolled. Eight patients underwent ablation for idiopathic RVOT PVCs, and 6 patients with structural heart disease underwent ablation for scar-related VTs. The recurrence of arrhythmias was assessed by 24-hour Holter electrocardiography monitoring or implantable cardioverter defibrillator interrogation. Results Fourteen patients were enrolled, age 51±13 years, 11 were man, 4 had previously failed radiofrequency ablation. Procedural and fluoroscopy times were 76±44 minutes and 9 (4–20) minutes, respectively. The median number of PFA applications was 16 (12-19) in the VT group and 8 (7-8) in the PVC group. Acute procedural success was achieved in 86% of patients. During a mean follow-up of 136±73 days, freedom from VT was 67% and a PVC burden Conclusions The ablation of idiopathic RVOT PVCs and scar-related VTs with the pentaspline PFA catheter is feasible with good acute and mid-term efficacy observed in our cohort. Further research involving larger cohorts and longer follow-up periods is needed to analyse the safety and define the role of PFA in VAs.

Background: Recurrences due to discontinuity in ablation lines are substantial after pulmonary vein isolation (PVI) with radiofrequency ablation for atrial fibrillation. Data are scarce regarding the durability predictors for very high-power short-duration (vHPSD, 90 W/4 s) ablation. Methods: A total of 20 patients were enrolled, who underwent 90 W PVI and a mandatory remapping procedure at 3 months. First-pass isolation (FPI) gaps, and acute pulmonary vein reconnection (PVR) sites were identified at the index procedure; and chronic PVR sites were identified at the repeated procedure. We analyzed parameters of ablation points (n = 1357), and evaluated their roles in predicting a composite endpoint of FPI gaps, acute and chronic PVR. Results: In total, 45 initial ablation points corresponding to gaps in the ablation lines were analyzed. Parameters associated with gaps were interlesion distance (ILD), baseline generator impedance, mean current, total charge, and loss of catheter–tissue contact. The optimal ILD cut-off for predicting gaps was 3.5 mm anteriorly, and 4 mm posteriorly. Conclusions: Biophysical characteristics dependent on generator impedance could affect the efficacy of vHPSD PVI. The use of smaller ILDs is required for effective and durable PVI with vHPSD compared to the consensus targets with lower power ablation, and lower ILDs for anterior applications seem necessary compared to posterior points.

Background: Atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) is predominantly attributed to pulmonary vein reconnection (PVR). Predictors of AF recurrence have been widely studied; however, data are scarce on procedural parameters that predict chronic PVR. We aimed to study PVR rates and predictors of PVR. Methods: We retrospectively included 100 patients who underwent repeated ablation due to AF recurrence after initial PVI with the CARTO system. PVR was determined during the repeated procedure by electrophysiological evaluation, and initial procedural characteristics predicting PVR were studied, including adherence to the CLOSE protocol, use of high power, first-pass isolation (FPI), and baseline generator impedance (BGI). Results: Thirty-eight patients underwent initial CLOSE-guided PVI, and sixty-two underwent initial non-CLOSE PVI. A repeat procedure was performed 23 ± 16 months after the initial procedure. In total, PVR was found in 192 of 373 PVs (51.5%), and all PVs were isolated in 17/100 (17%) patients. Factors associated with all PVs being isolated were adherence to the CLOSE protocol, a higher power setting, the presence of bilateral FPI, and lower BGI (88% vs. 28%, p < 0.0001; 37.5 W vs. 30 W, p = 0.0276; 88.2% vs. 40.4%, p = 0.0007; and 127.6 Ω vs. 136.6 Ω, p = 0.0027, respectively). In initial procedures with adherence to the CLOSE protocol, the FPI rate was significantly higher (73.7% vs. 25%, p < 0.0001), while there were no significant differences in terms of procedure time and left atrial dwell time (81 vs. 85 min, p = 0.83; and 60 vs. 58 min, p = 0.08, respectively). BGI ≥ 130 Ω (AUC = 0.7403, sensitivity: 77.1%, specificity: 68.8%, p = 0.0032) was associated with a significantly higher probability of PVR (OR = 6.757; p < 0.0001). In multivariable analysis, independent predictors for PVR were non-adherence to the CLOSE protocol and BGI ≥ 130 Ω. Conclusions: Our findings indicate that adherence to the CLOSE protocol and baseline generator impedance < 130 Ω during AF ablation are independent predictors of PVI durability.

BACKGROUND: High-power short-duration ablation has shown impressive efficacy and safety for pulmonary vein isolation (PVI); however, initial efficacy results with very high power short-duration ablation were discouraging. This study compared the long-term durability of PVI performed with a 90- versus 50-W power setting. METHODS: Patients were randomized 1:1 to undergo PVI with the QDOT catheter using a power setting of 90 or 50 W. Three months after the index procedure, patients underwent a repeat electrophysiology study to identify pulmonary vein reconnections. Patients were followed for 12 months to detect AF recurrences. RESULTS: We included 46 patients (mean age, 64 years; women, 48%). Procedure (76 versus 84 minutes; P =0.02), left atrial dwell (63 versus 71 minutes; P =0.01), and radiofrequency (303 versus 1040 seconds; P P =0.01). There was no difference in first-pass isolation (83% versus 82%; P =1.0) or acute reconnection (4% versus 14%; P =0.3) rates between 90 and 50 W. Forty patients underwent a repeat electrophysiology study. Durable PVI on a per PV basis was present in 72/78 (92%) versus 68/77 (88%) PVs in the 90- and 50-W energy setting groups, respectively; effect size: 72/78−68/77=0.040, lower 95% CI=−0.051 (noninferiority limit=−0.1, ie, noninferiority is met). No complications occurred. There was no difference in 12-month atrial fibrillation-free survival between the 90- and 50-W groups ( P =0.2). CONCLUSIONS: Similarly high rates of durable PVI and arrhythmia-free survival were achieved with 90 and 50 W. Procedure, left atrial dwell, and radiofrequency times were shorter with 90 W compared with 50 W. The sample size is too small to conclude the safety and long-term efficacy of the high and very high-power short-duration PVI; further studies are needed to address this topic. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05459831.

Cerebral thrombo-embolism is a dreaded complication of pulmonary vein isolation (PVI) for atrial fibrillation; its surrogate, silent cerebral embolism (SCE) can be detected by diffusion-weighted brain magnetic resonance imaging (bMRI). Initial investigations have raised a concern that very high-power, short-duration (vHPSD; 90 W/4 s) temperature-controlled PVI with the QDOT Micro catheter may be associated with a higher incidence of SCE compared with low-power long-duration ablation. We aimed to assess the incidence of procedural complications of vHPSD PVI with an emphasis on cerebral safety. We enrolled 328 consecutive patients undergoing their PVI procedure using vHPSD. A subgroup of 61 consecutive patients underwent diffusion-weighted bMRI within 24 h of the procedure, and incidence and predictors of SCE were studied. The mean procedure time and left atrial dwell time for the overall cohort were 69.6 ± 24.1 and 46.5 ± 21.5 min, respectively. First-pass isolation was achieved in 82%. No stroke or transient ischaemic attack occurred. Silent cerebral embolism was identified in 5 of 61 patients (8.2%). Silent cerebral embolism following procedures was significantly associated with lower baseline generator impedance (105.8 vs. 112.6 Ω, P < 0.0001) and with intermittent loss of catheter–tissue contact during ablation (14.1% vs. 6.1%, P < 0.0001). Very high-power, short-duration PVI is a safe technique with an excellent acute success rate. Silent cerebral embolism incidence in our cohort was below the previously reported range, with no clinically overt cerebral complications. Lower baseline generator impedance and loss of contact during ablation may contribute to a higher risk of SCEs.

Remote monitoring (RM) is the newest function of cardiac implantable electronic devices (CIEDs). In our observational retrospective analysis, we aimed to assess whether telecardiology could be a safe alternative to routine outpatient examinations during the COVID-19 pandemic. The in- and outpatient visits, the number of acute cardiac decompensation episodes, the RM data from CIEDs, and general condition were examined via questionnaires (KCCQ, EQ-5D-5L). Regarding the enrolled 85 patients, the number of personal patient appearances was significantly lower in the year following the pandemic outbreak compared to the previous year (1.4 ± 1.4 and 1.9 ± 1.2, p = 0.0077). The number of acute decompensation events was five before and seven during lockdown (p = 0.6). Based on the RM data, there was no significant difference in heart failure (HF) markers (all related p > 0.05); only patient activity increased after restrictions were lifted compared to that before the lockdown (p = 0.03). During restrictions, patients reported increased anxiety and depression compared to their previous state (p < 0.001). There was no subjective change in the perception of HF symptoms (p = 0.7). Based on the subjective perception and CIED data, the quality of life of patients with CIED did not deteriorate during the pandemic, but their anxiety and depression intensified. Telecardiology may be a safe alternative to routine inpatient examination.