Pulmonary vein isolation durability after very high-power short-duration ablation utilizing a very-close protocol - The FAST AND FURIOUS redo study.

Background: Very high-power short-duration (vHP-SD) radiofrequency (RF) ablation of atrial fibrillation (AF) treatment by pulmonary vein isolation (PVI) aims for safer, more effective and faster procedures. Although acute efficacy and safety for PVI was recently shown data on chronic PVI durability is limited. Here chronic PVI durability was evaluated during repeat electrophysiological procedures in patients after initial vHP-SD and conventional RF based PVI. Methods: A total of 25 consecutive patients with repeat left atrial procedures after initial vHP-SD based PVI were included in this study. Twenty-five patients with previous conventional RF based PVI and repeat left atrial procedures served as control (control group). Results: For index procedures the median RF time was 328 (277, 392) seconds (vHP-SD) and 1470 (1310, 1742) seconds (control); p < 0.001, the median procedure time was 55 (53, 68) minutes (vHP-SD) and 110 (94, 119) (control); p < 0.001). First pass isolation rate was 84 % (vHP-SD) and 88 % (control, p = 0.888). No differences for severe adverse events (vHP-SD: 1/25, 4 % vs. control: 0/25, 0 %; p = 0.676 were detected.Chronic durability of all PVs was assessed in vHP-SD: 16/25 (64 %) and control: 8/25 (32 %) patients (p = 0.023) and vHP-SD: 81 % and control: 62 % of PVs were found to be isolated (p = 0.003). For right PVs vHP-SD: 84 % vs. control: 60 % of PVs (p < 0.001) and for left PVs vHP-SD: 78 % vs. control: 64 % (p = 0.123) were found to be isolated. Conclusions: PVI solely utilizing vHP-SD via a very close-protocol provides fast, safe and effective acute PVI. High rates of chronically isolated pulmonary veins have been detected.

Impact of pulsed field ablation on intraluminal esophageal temperature.

INTRODUCTION: Atrio-esophageal fistula after esophageal thermal injury (ETI) is one of the most devastating complications of available energy sources for atrial fibrillation (AF) ablation. Pulsed field ablation (PFA) uses electroporation as a new energy source for catheter ablation with promising periprocedural safety advantages over existing methods due to its unique myocardial tissue sensitivity. In preclinical animal studies, a dose-dependent esophageal temperature rise has been reported. In the TESO-PFA registry intraluminal esophageal temperature (TESO) changes in a clinical setting are evaluated. METHODS: Consecutive symptomatic AF patients (62 years, 67% male, 61% paroxysmal AF, CHA2 DS2 Vasc Score 2) underwent first-time PFA and were prospectively enrolled into our registry. Eight pulse trains (2 kV/2.5 s, bipolar, biphasic, x4 basket/flower configuration each) were delivered to each pulmonary vein (PV). Two extra pulse trains per PV in flower configuration were added for wide antral circumferential ablation. Continuous intraluminal esophageal temperature (TESO) was monitored with a 12-pole temperature probe. RESULTS: Median TESO change was statistically significant and increased by 0.8 ± 0.6°C, p < .001. A TESO increase ≥ 1°C was observed in 10/43 (23%) patients. The highest TESO measured was 40.3°C. The largest TESO difference (∆TESO) was 3.7°C. All patients remained asymptomatic considering possible ETI. No atrio-esophageal fistula was reported on follow-up. CONCLUSION: A small but significant intraluminal esophageal temperature rise can be observed in most patients during PFA. TESO rise over 40°C is rare. The clinical implications of the observed findings need to be further evaluated.

Pulsed Field Ablation-Based Pulmonary Vein Isolation Using a Simplified Single-Access Single-Catheter Approach　- The Fast and Furious PFA Study.

BACKGROUND: Pulsed field ablation (PFA) is a non-thermal energy source with promising safety and efficacy advantages. We aimed to develop a convenient, safe, effective and fast method of pulmonary vein isolation (PVI) utilizing a penta-spline PFA catheter via a single femoral vein and a venous closure system.Methods and Results: Consecutive patients (n=50; mean age: 63.6±10.7 years, 38% female) presenting with AF (paroxysmal AF: 56%) underwent first-time PVI via PFA. A single ultrasound-guided femoral vein puncture and a single transseptal puncture were used. After PVI using the penta-spline PFA catheter, extra pulse trains were added to the posterior wall for wide antral circumferential ablation. A venous closure system was used and a Donati suture was performed. The pressure bandage was removed after 1 h. A total of 196 PVs were identified and isolated with PFA only. The mean procedural time was 27.4±6.6 min, and the mean dwelling time was 14.4±5.5 min. Time to ambulation was 3.3±3.1 h. No severe complications occurred. During a mean follow-up of 6.5±2.1 months, 41/50 patients (82%) remained in sinus rhythm. CONCLUSIONS: The combination of a single venous puncture, single transseptal puncture approach using PFA and vascular closure device resulted in a 100% rate of acute PVI and an extraordinarily fast procedure and time to ambulation. The rate of periprocedural complications was low.

Novel or established cryoballoon ablation system for pulmonary vein isolation: the prospective ICE-AGE-1 study.

AIMS: Catheter ablation with a cryoballoon (CB) provides effective and durable pulmonary vein (PV) isolation (PVI) associated with encouraging clinical outcome data. The novel POLARx CB incorporates unique features, which may translate into improved safety, efficacy, and outcomes. The ICE-AGE-1 study aimed to assess the efficacy, safety, and 1-year clinical follow-up of the POLARx CB in comparison to the Arctic Front Advance Pro CB (AF-CB4). METHODS AND RESULTS: A total of 103 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) who underwent POLARx-based PVI (POLARx group) were prospectively enrolled and were compared to 102 consecutive patients previously treated with the AF-CB4 (AF-CB4 group). The mean age was 68.7 ± 10.2 (POLARx) and 65.7 ± 12 (AF-CB4, P = 0.0551) years. A total of 412 (POLARx) and 404 (AF-CB4) PVs were identified. All PVs, except for one PV in the POLARx group, were successfully isolated. A significant difference regarding the mean minimal CB temperature reached using the POLARx CB (-56.1 ± 8.3°C) and AF-CB4 (-46.9 ± 10.1°C) was observed (P < 0.0001). Real-time PVI was visualized in 71% of PVs in the POLARx group and 46% of them in the AF-CB4 group (P < 0.001). The mean procedure time was comparable: 54.5 ± 17.1 min for POLARx and 59.4 ± 18.6 min for AF-CB4 (P = 0.0509). No differences were observed in terms of periprocedural complications. There were comparable rates in freedom of AF or atrial tachycardia recurrence after 12 months, beyond a 90-day long blanking period: 78.9% in the POLARx group vs. 77.2% in the AF-CB4 group (P = 0.804). CONCLUSION: The novel POLARx CB showed similar safety, efficacy, and 1-year recurrence-free survival rates compared to the AF-CB4. A higher rate of real-time electrical PV recordings and significantly lower balloon temperatures were observed using the POLARx as compared to AF-CB4.

Very high-power short-duration ablation for pulmonary vein isolation utilizing a very-close protocol-the FAST AND FURIOUS PVI study.

AIMS: The very high-power short-duration (vHP-SD) radiofrequency (RF) ablation concept of atrial fibrillation (AF) treatment by pulmonary vein isolation (PVI) aims for safer, more effective, and faster procedures. Utilizing conventional ablation, the 'close protocol' has been verified. Since lesion formation of vHP-SD ablation creates wider but shallower lesions we adapted the close protocol to an individualized and tighter 'very-close protocol' of 3-4 mm of inter-lesion distance (ILD) at the anterior and 5-6 mm at the posterior aspect of the left atrium using vHP-SD only. Here, we evaluated the safety and efficacy of vHP-SD ablation for PVI utilizing a very-close protocol in comparison with standard ablation. METHODS AND RESULTS: A total of 50 consecutive patients with symptomatic AF were treated with a very-close protocol utilizing vHP-SD (vHP-SD group). The data were compared with 50 consecutive patients treated by the ablation-index-guided strategy (control group). The mean RF time was 352 ± 81 s (vHP-SD) and 1657 ± 570 s (control, P < 0.0001), and the mean procedure duration was 59 ± 13 (vHP-SD) and 101 ± 38 (control, P < 0.0001). The first-pass isolation rate was 74% (vHP-SD) and 76% (control, P = 0.817). Severe adverse events were reported in 1 (2%, vHP-SD) and 3 (6%, control) patients (P = 0.307). A 12-month recurrence-free survival was 78% (vHP-SD) and 64% (control, P = 0.142). PVI durability assessed during redo-procedures was 75% (vHP-SD) vs. 33% (control, P < 0.001). CONCLUSIONS: PVI solely utilizing vHP-SD via a very-close protocol provides safe and effective procedures with a high rate of first-pass isolations. The procedure duration and ablation time were remarkably low. A 12-month follow-up and PVI durability are promising.

Distinguishing Incubation and Acute Disease Stages of Mild-to-Moderate COVID-19.

While numerous studies have already compared the immune responses against SARS-CoV-2 in severely and mild-to-moderately ill COVID-19 patients, longitudinal trajectories are still scarce. We therefore set out to analyze serial blood samples from mild-to-moderately ill patients in order to define the immune landscapes for differently progressed disease stages. Twenty-two COVID-19 patients were subjected to consecutive venipuncture within seven days after diagnosis or admittance to hospital. Flow cytometry was performed to analyze peripheral blood immune cell compositions and their activation as were plasma levels of cytokines and SARS-CoV-2 specific immunoglobulins. Healthy donors served as controls. Integrating the kinetics of plasmablasts and SARS-CoV-2 specific antibodies allowed for the definition of three disease stages of early COVID-19. The incubation phase was characterized by a sharp increase in pro-inflammatory monocytes and terminally differentiated cytotoxic T cells. The latter correlated significantly with elevated concentrations of IP-10. Early acute infection featured a peak in PD-1+ cytotoxic T cells, plasmablasts and increasing titers of virus specific antibodies. During late acute infection, immature neutrophils were enriched, whereas all other parameters returned to baseline. Our findings will help to define landmarks that are indispensable for the refinement of new anti-viral and anti-inflammatory therapeutics, and may also inform clinicians to optimize treatment and prevent fatal outcomes.

Single-dose SARS-CoV-2 vaccinations with either BNT162b2 or AZD1222 induce disparate Th1 responses and IgA production.

BACKGROUND: While vaccination programs against the severe acute respiratory syndrome virus 2 (SARS-CoV-2) are globally ongoing, disparate strategies for the deployment of spike antigen show varying effectiveness. METHODS: In order to explore this phenomenon, we sought to compare the early immune responses against AZD1222 and BNT162b2. SARS-CoV-2 seronegative participants received a single dose of either vaccine and were analyzed for immune cell, effector T cell, and antibody dynamics. RESULTS: AZD1222 induced transient leukopenia and major changes among innate and adaptive subpopulations. Both vaccines induced spike protein-specific effector T cells which were dominated by type 1 helper T cell responses following AZD1222 vaccination. A significant reduction of anti-inflammatory T cells upon re-stimulation was also restricted to AZD1222 vaccinees. While IgM and IgG were the dominant isotypes elicited by AZD1222, BNT162b2 led to a significant production of IgG and IgA. CONCLUSIONS: Our results suggest that the strategy for spike protein delivery impacts on how and to what extent immune priming against the main SARS-CoV-2 antigen proceeds.

Second-generation cryoballoon-based pulmonary vein isolation: Lessons from a five-year follow-up.

BACKGROUND: Pulmonary vein isolation (PVI) using the second-generation cryoballoon (CB2) for atrial fibrillation (AF) treatment has demonstrated encouraging procedural success rates and mid-term results. However, long-term follow-up data on outcome is sparse. The current study is reporting on five-year clinical outcomes following CB2-based PVI in patients with paroxysmal AF (PAF) and persistent AF (PersAF). METHODS: A total of 139 patients underwent index CB2-based PVI patients (PAF: n = 105, 76% and PersAF: n = 34, 34%) in two electrophysiology centers. Freeze-cycle duration was 240 s. After successful PVI a bonus freeze-cycle of the same duration was applied in the first 71 patients while the bonus-freeze was omitted in 68 following patients. Three patients (2.2%) were lost to follow-up. RESULTS: After a median follow-up duration of 60 months (interquartile range: 46, 72 months) 74/136 (54.4%) patients remained in stable sinus rhythm (PAF: 62/104, 59.6%; PersAF: 15/32, 46.9%). Significant differences were observed concerning 5-year clinical outcome between PAF and PersAF patients (p = 0.0315). After a mean of 1.32 ± 0.6 procedures (2nd and 3rd procedure by radiofrequency ablation) and a median follow-up duration of 60 (37, 68) months 90/136 (66.2%) patients remained in stable sinus rhythm (PAF: 72/104 (69.2%), PersAF: 21/32 (65.6%), p = 0.0276). For the comparison of bonus-freeze vs no-bonus-freeze protocols no differences were observed (53.5% vs 57.4%, p = 0.650). CONCLUSIONS: The five-year single-procedure success rate for CB2-based PVI was 54.4% and increased to 66.2% following repeat RF-based procedures. No differences were detected comparing bonus-freeze and no-bonus-freeze protocols.