Aims: A novel three-dimensional mapping platform combined with a lattice-tip catheter that can toggle between monopolar pulsed field ablation (PFA) and radiofrequency energy delivery was recently launched. So far, the system was predominantly applied in general anaesthesia (GA), not in deep sedation. Methods and results: Patients with symptomatic paroxysmal or persistent atrial fibrillation (AF) were enrolled, and pulmonary vein isolation (PVI) and ablation of additional linear lesion sets were performed either in GA or in deep sedation. Pulsed field ablation was applied exclusively to perform ipsilateral PVI. A total of 63 patients (35% female, 75% persistent AF, mean age 64 ± 9 years) were included in the analysis with 23 patients treated in GA and 40 patients in deep sedation. Acute efficacy was comparable in both groups with a PVI rate of 100%. Additional 74 lesion sets were performed in the total cohort. Mean procedure and lab occupancy time in the GA and deep sedation group was 96 ± 24 min vs. 100 ± 23 min (P = 0.52) and 165 ± 40 min vs. 131 ± 35 min (P = 0.0008). Mean dose area product was 489 (216;1093) vs. 452 (272;882) cGycm2 in the GA and the deep sedation group (P = 0.82). There was one conversion from deep sedation to GA. There were no map shifts observed in any group. Pericardial tamponade occurred in one patient of the deep sedation group. Conclusion: The use of a novel ablation platform in conjunction with a lattice-tip catheter in deep sedation is feasible, effective, and associated with significantly shorter lab occupancy time when compared with GA.

Background and Aims: Vascular access site complications are the most common procedure-related adverse event of atrial fibrillation catheter ablation. Whether ultrasound-guided femoral venous puncture reduces these vascular access complications remains uncertain. Methods: In this investigator-initiated, multicentre, open-label, superiority trial, patients undergoing atrial fibrillation or left atrial tachycardia catheter ablation were randomized to an ultrasound-guided venous puncture strategy (intervention group) or to a conventional venous puncture group guided by palpation (control group). The composite primary outcome was the occurrence of venous access site complications until 30 days after the procedure, defined as arteriovenous fistula, false aneurysm, or access site bleeding requiring intervention or leading to prolonged hospitalization. Secondary endpoints included procedure duration, puncture duration, procedure-related stroke/transient ischaemic attack within 30 days, number of unintended arterial punctures, and number of failed venous access attempts, as well as hospital stay duration. Results: In six centres, 986 patients were randomized. A total of 496 patients were assigned to the ultrasound-guided puncture group, and 490 patients to the conventional puncture group. The trial was stopped for efficacy, following the first interim analysis after enrolment of half of the planned patients. The composite primary outcome occurred in 3 patients (0.6%) in the intervention group and 16 patients (3.3%) in the control group (risk ratio 0.19; 95% confidence interval 0.05–0.63; P = .002). Additionally, ultrasound-guided venous puncture significantly reduced the rate of an unintended arterial puncture (2% vs 16%, P < .0001) and the rate of unsuccessful venous access attempts requiring crossover to the other group (0.2% vs 8.2%, P < .0001). Conclusions: Ultrasound-guided venous access for atrial fibrillation ablation procedures significantly reduced vascular access site complications. ULYSSES ClinicalTrials.gov number: NCT06403527.

Aims: Pulsed field ablation (PFA) is a non-thermal energy modality for ablation of atrial fibrillation (AF). Although PFA has demonstrated an excellent overall safety profile, increasing evidence suggests an association with intravascular haemolysis, and acute kidney injury (AKI). However, the extent of haemolysis across different PFA catheters remains poorly characterized and warrants further investigation. Methods and results: We prospectively enrolled 239 patients undergoing AF ablation using the pentaspline (n = 107), balloon-in-basket (n = 71), or lattice-tip (n = 61) catheter. Laboratory markers of haemolysis, myocardial injury, renal function and haemoglobin were collected pre- and 24h post-procedure. Significant haptoglobin depletion was observed exclusively with pentaspline, [pre 99.8 mg/dL (70.2–122) vs. post 55.7 mg/dL (23.2–91.8); P < 0.001] Reductions with the lattice-tip (P = 0.074) and the balloon-in-basket (P = 0.201) catheter did not reach statistical significance. AKI was only observed with the pentaspline catheter (pentaspline: 4.9%; balloon-in-basket: 0.0%; lattice tip: 0.0%; P = 0.020). Myocardial markers increased across all groups, but significantly higher in pentaspline and balloon-in-basket (P = n.s.) vs. lattice-tip (P < 0.001 vs. pentaspline, P < 0.001 vs. balloon in basket). Conclusion: In this large cohort, contemporary PFA systems appear safe but catheter design influences the extent of haemolysis, AKI, and myocardial injury. The pentaspline catheter was associated with the greatest haemolytic effect and higher transient AKI, without clinically relevant reductions in haemoglobin or persistent renal impairment. Higher levels of myocardial injury in the pentaspline and balloon-in-basket groups correspond to the larger lesion footprints of these devices.

Aims: Previous clinical studies on pulmonary vein isolation (PVI) with a radiofrequency balloon (RFB) reported safe and effective procedures using conventional ablation settings with 20/60 s RF delivery via posterior/anterior (PST/ANT) electrodes. The latest evidence suggests that reducing the application time to 15 s (s) on the posterior wall when facing the oesophageal region is as effective as applying 20 s. To prospectively assess whether reducing RF time on PST/ANT segments to 15/45 s can ensure sufficient quality of lesion metrics and compare the new shortened ablation settings with the conventional one in terms of safety, and effectiveness at 1-year. Methods and results: A total of 641 patients from seven European centres were enrolled in a collaborative registry, with 374 in the conventional RF delivery group and 267 in the shortened RF delivery group. Procedural outcomes, lesion metrics, and safety profiles were assessed and compared between the groups. Freedom of any atrial tachycarrythmias at one year was 85.4% and 88.2% in the SHRT and CONV groups, respectively. The shortened RF delivery strategy was associated with significantly shorter procedure times (median 63.5 vs. 96.5 min, P < 0.001) and shortened fluoroscopy exposure (median 10.0 vs. 14.0 min, P < 0.001) compared to conventional delivery. Efficacy metrics, including first-pass isolation rates and time to isolation, were comparable between groups. Shortened RF delivery was associated with a lower incidence of procedural complications (1.4% vs. 5.3%, P = 0.04) and optimized thermal characteristics. Conclusion: Analyses from the COLLABORATE registry demonstrate that shortening RF energy delivery times to 15/45 s (PST/ANT) during PVI with the RFB resulted in comparable freedom from recurrent atrial tachyarrhythmia compared to conventional delivery times with comparable efficiency and safety.