Background: Atrial fibrillation (AF) recurrence following catheter ablation remains high. Recent studies have shown a relation between epicardial adipose tissue and AF. epicardial adipose tissue secretes several proinflammatory and anti-inflammatory adipokines that directly interact with the adjacent myocardium. The aim of the current study was to evaluate whether posterior left atrial (LA) adipose tissue attenuation, as marker of inflammation, is related to AF recurrences after catheter ablation. Methods: Consecutive patients with symptomatic AF referred for first AF catheter ablation who underwent computed tomography were included. The total epicardial adipose tissue and posterior LA adipose tissue were manually traced and adipose tissue was automatically recognized as tissue with Hounsfield units (HU) between −195 and −45. The attenuation value of the posterior LA adipose tissue was assessed, and the population was divided according to the mean HU value (−96.4 HU). Results: In total, 460 patients (66% male, age 61±10 years) were included in the analysis. After a median follow-up of 18 months (interquartile range, 6–32), 168 (37%) patients had AF recurrence. Patients with higher attenuation (≥−96.4 HU) of the posterior LA adipose tissue showed higher AF recurrence rates compared with patients with lower attenuation (<−96.4 HU; log-rank test P =0.046). Univariate analysis showed an association between AF recurrence and higher posterior LA adipose tissue attenuation (≥−96.4 HU; P <0.05). On multivariable analysis, posterior LA adipose tissue attenuation (hazard ratio, 1.26 [95% CI, 0.90–1.76]; P =0.181) remained a promising predictor of AF recurrence following catheter ablation. Conclusions: Posterior LA adipose tissue attenuation is a promising predictor of AF recurrence in patients who undergo catheter ablation. Higher adipose tissue attenuation might signal increased local inflammation and serve as an imaging biomarker of increased risk of AF recurrence. Graphic A graphic abstract is available for this article.

Aims: Clinical studies with protocol-mandated workflow and monitoring have analysed performance of pulsed field ablation (PFA) for treating atrial fibrillation (AF). The FARADISE registry captures global use of the pentaspline PFA catheter in real-world clinical practice with a follow-up of 3 years. Methods and results: FARADISE is a prospective, non-randomized, multi-national registry (NCT05501873) that enrolled subjects clinically indicated for ablation using the pentaspline PFA catheter per medical judgement and hospital standard-of-care. Procedural characteristics, safety, and clinical effectiveness up to 12-months were collected. In total, 1158 AF patients received PFA across 48 centres in 21 countries (64 ± 11 years, 33% female, 90% de novo, 65% paroxysmal AF). Pulmonary vein isolation (PVI)-only procedures were performed in 80.8% of paroxysmal vs. 57.5% for non-paroxysmal patients (P < 0.01). Median procedure, left atrial dwell, and fluoroscopy times were 51[40–70], 31[24–41], and 12[8–17] min, respectively. The rate of early onset serious adverse events was 1.5% and did not differ by ablation strategy or AF indication. At 1-year, clinical effectiveness was 80.8% for paroxysmal AF and 67.7% for non-paroxysmal AF, with no difference within indication by lesion set (paroxysmal: 81.2% PVI-only vs. 79.0% PVI+, P = 0.65; non-paroxysmal: 67.5% PVI-only vs. 67.7% PVI+, P = 0.79). Acute results reinforce a short procedural learning curve with no difference in 1-year effectiveness by operator experience. Conclusion: The FARADISE registry provides a snapshot of real-world clinical use of the pentaspline PFA catheter. Acute results demonstrate favourable procedural and safety outcomes regardless of AF indication. One-year outcomes are encouraging, with no differences seen within indication based on ablation strategy.

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.

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 <0.0001) times were shorter with 90- versus 50-W procedures, while the number of radiofrequency applications was higher with 90 versus 50 W (77 versus 67; 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.

Introduction: Our pilot study aimed to evaluate the role of local impedance drop in lesion formation during pulmonary vein isolation with a novel contact force sensing ablation catheter that records local impedance as well and to find a local impedance cut-off value that predicts successful lesion formation. Materials and methods: After completing point-by-point radiofrequency pulmonary vein isolation, the success of the applications was evaluated by pacing along the ablation line at 10 mA, 2 ms pulse width. Lesions were considered successful if loss of local capture was achieved. Results: Out of 645 applications, 561 were successful and 84 were unsuccessful. Compared to the unsuccessful ablation points, the successful applications were shorter (p = 0.0429) and had a larger local impedance drop (p<0.0001). There was no difference between successful and unsuccessful applications in terms of mean contact force (p = 0.8571), force-time integral (p = 0.0699) and contact force range (p = 0.0519). The optimal cut-point for the local impedance drop indicating successful lesion formation was 21.80 Ohms on the anterior wall [AUC = 0.80 (0.75–0.86), p<0.0001], and 18.30 Ohms on the posterior wall [AUC = 0.77 (0.72–0.83), p<0.0001]. A local impedance drop larger than 21.80 Ohms on the anterior wall and 18.30 Ohms on the posterior wall was associated with an increased probability of effective lesion creation [OR = 11.21, 95%CI 4.22–29.81, p<0.0001; and OR = 7.91, 95%CI 3.77–16.57, p<0.0001, respectively]. Conclusion: The measurement of the local impedance may predict optimal lesion formation. A local impedance drop > 21.80 Ohms on the anterior wall and > 18.30 Ohms on the posterior wall significantly increases the probability of creating a successful lesion.

Purpose: To evaluate factors associated with pseudoaneurysm (PSA) development. Methods: Between January 2016 and May 2020, 30,196 patients had invasive vascular radiological or cardiac endovascular procedures that required arterial puncture. All patients with PSA were identified. A matched (age, gender, and type of the procedure) control group of 134 patients was created to reveal predictors of PSA formation. Results: Single PSAs were found in 134 patients. Fifty-three PSAs developed after radiological procedures (53/6555 [0.8%]), 31 after coronary artery procedures (31/18038 [0.2%]), 25 after non-coronary artery cardiac procedures (25/5603 [0.4%]), and 25 due to procedures in which the arterial puncture was unintended. Thirty-four PSAs (25.4%) were localized to the upper extremity arteries (vascular closure device [VCD], N = 0), while 100 (74.6%) arose from the lower extremity arteries (VCD, N = 37). The PSA prevalence was 0.05% (10/20478) in the radial artery, 0.1% (2/1818) in the ulnar artery, 1.2% (22/1897) in the brachial artery, and 0.4% (99/22202) in the femoral artery. Treatments for upper and lower limb PSAs were as follows: bandage replacement (32.4% and 14%, respectively), ultrasound-guided compression (11.8% and 1%, respectively), ultrasound-guided thrombin injection (38.2% and 78%, respectively), and open surgery (17.6% and 12%, respectively). Reintervention was necessary in 19 patients (14.2%). The prevalence of PSA for the punctured artery with and without VCD use was 37/3555 (1%) and 97/27204 (0.4%), respectively (OR, 2.94; 95% CI, 1.95–4.34; P<0.001). The effect of red blood cell (RBC) count (P<0.001), hematocrit value (P<0.001), hemoglobin value (P<0.001), international normalized ratio (INR; P<0.001), RBC count—INR interaction (P = 0.003), and RBC count—VCD use interaction (P = 0.036) on PSA formation was significant. Conclusion: Patients in whom the puncture site is closed with a VCD require increased observation. Preprocedural laboratory findings are useful for the identification of patients at high risk of PSA formation.