Esophageal Endoscopy After Catheter Ablation of Atrial Fibrillation Using Ablation-Index Guided High-Power: Frankfurt AI-HP ESO-I.

OBJECTIVES: This study sought to investigate the safety profile of a novel ablation index-guided high-power short-duration (AI-HP) pulmonary vein isolation (PVI) in terms of endoscopic esophageal lesions. BACKGROUND: The risk of esophageal injury during PVI is a major concern while ablating the posterior wall for patients with atrial fibrillation. Luminal esophageal temperature (LET) rise during ablation is a surrogate for esophageal lesion development. METHODS: A total of 122 consecutive symptomatic atrial fibrillation patients underwent AI-HP PVI (50 W throughout the ablation, AI anterior wall/posterior wall: 550/400). All patients were under LET monitoring (cutoff LET 39°C) during the ablation procedure, and patients with LET rise received esophageal endoscopy examination 1 to 3 days after the ablation. Ablation lesion data of the sites with LET rise were analyzed. RESULTS: Procedural PVI success rate was 100%. Per procedure, the mean radiofrequency ablation time, procedural time, and fluoroscopic time were 11.9 ± 2.7 min, 54.8 ± 9 min, and 5.5 ± 1.6 min. The incidence of LET >39°C was 47%, and the mean peak LET was 41.2 ± 1.8°C. The rate of endoscopic detected lesion was 2 of 57 (3.5%). No perforation or atrial-esophageal fistula was found. The mean contact force, application duration, impedance drop, and AI values at the sites with LET rise were 22.1 ± 8.9 g, 7 ± 2.4 s, 9.4 ± 4.6 Ω, and 419 ± 44.6. CONCLUSIONS: AI-HP (50 W) ablation appears to be a highly efficient ablation technique for PVI. The incidence of esophageal injury during AI-HP PVI seems markedly low. AI-HP ablation targeting AI 400 in combination with multisensor esophageal temperature monitoring for the left atrial posterior wall appears safe and efficient.

Cryoballoon pulmonary vein isolation in treating atrial fibrillation using different freeze protocols: The "ICE-T 4 minutes vs 3 minutes" propensity-matched study (Frankfurt ICE-T 4 vs. 3).

BACKGROUND: Time-to-isolation (TTI) guided second-generation cryoballoon (CB2) ablation has been shown to be effective for pulmonary vein isolation (PVI). OBJECTIVE: The objective of this paper is to compare the safety and clinical outcome of CB2 PVI using the TTI guided 4 minutes vs 3 minutes freeze protocol. METHODS: This was a propensity-matched study based on an institutional database. Symptomatic atrial fibrillation (AF) patients who underwent CB2 PVI and systematic follow-up were consecutively included. RESULTS: A total of 573 patients were identified, of them 214 (107 matched-pairs) symptomatic AF (paroxysmal AF: 61%, persistent AF: 39%) patients (age: 67.7 ± 11.2 years) were analyzed. The baseline characteristics were comparable between the two groups. Procedural time was significantly longer in the 4 minutes group compared to 3 minutes group (67.2 ± 21.8 vs 55.9 ± 16.9 minutes, P < .0001). During a mean follow-up of 2 years, the 4 minutes group was associated with a significantly higher rate of freedom from arrhythmia recurrence compared with the 3 minutes group (66.4% vs 56.1%, P = .009), which was mainly driven by patients with persistent AF. The multivariate regression showed that the 4 minutes freeze was the independent predictor of freedom from arrhythmia recurrence. During the repeat procedure, the 4 minutes group was associated with a significantly higher rate of durable PVI. There was no difference regarding procedural adverse events between the two groups. CONCLUSION: As compared with the 3 minutes freeze, the TTI guided 4 minutes freeze is associated with a significantly higher rate of arrhythmia-free and durable PVI without compromising the safety profile, patients with persistent AF may benefit from the TTI guided 4 minutes freeze more pronouncedly.

Catheter ablation of atrial fibrillation using ablation index-guided high power (50 W) for pulmonary vein isolation with or without esophageal temperature probe (the AI-HP ESO II).

BACKGROUND: High-power, short-duration ablation for pulmonary vein isolation (PVI) in the treatment of atrial fibrillation (AF) facilitates the procedure and improve effectiveness; however, esophageal injury remains a safety concern. OBJECTIVE: The purpose of this study was to investigate the role of luminal esophageal temperature (LET) monitoring during high-power ablation for PVI in terms of endoscopic esophageal lesion. METHODS: Patients with symptomatic AF underwent ablation index-guided high-power (AI-HP) PVI (50 W; AI anterior wall/posterior wall: 550/400). In the first consecutive set of patients, an insulated esophageal temperature probe was used for LET monitoring (cutoff LET >39°C) (group A). In the second consecutive set of patients, the probe was not used (group B). All patients were scheduled to undergo esophageal endoscopy 1-3 days after ablation. RESULTS: A total of 120 patients (60 group A; 60 group B) were included in the study (mean age 67.8 years; 64% male). Baseline characteristics and procedural outcomes were similar between the 2 groups. Procedural PVI was achieved in all patients. First-pass PVI rate was 96.6%. Mean procedural radiofrequency (RF) time was 11.5 minutes, mean procedural time was 55.5 minutes, and fluoroscopic time was 5.6 minutes. Mean contact force at the LA posterior wall was 23 g, and mean RF ablation time at the LA posterior wall was 3.2 minutes. Two patients in group A and 1 patient in group B had endoscopic small esophageal lesions (P = .99). No serious procedural adverse events were observed. CONCLUSION: Among patients undergoing AI-HP (50 W) PVI, the incidences of ablation-related endoscopic esophageal lesion in patients with and those without use of a temperature probe for LET monitoring (cutoff 39°C) were comparably low.

Rapid down modulation of P-selectin glycoprotein ligand-1 (PSGL-1, CD162) by G-CSF in humans.

BACKGROUND: In vitro and animal studies suggest a critical role for P-selectin glycoprotein ligand-1 (PSGL-1) in the regulation of WBC adhesion and neutrophil counts. As WBC activation decreases PSGL-1 expression on WBCs in vitro, the effects of G-CSF on PSGL-1 expression were examined. STUDY DESIGN AND METHODS: Two different G-CSF doses (1 and 5 microg/kg IV) were compared with high-dose dexamethasone (1 mg/kg twice daily) and placebo in a randomized, double-blind, four-way cross-over trial in eight healthy volunteers. Surface expression of WBC adhesion molecules was quantified by flow cytometry. RESULTS: Both G-CSF and dexamethasone led to a delayed down regulation of L-selectin. In contrast, G-CSF rapidly down regulated PSGL-1 expression on neutrophils within 90 minutes, whereas neither dexamethasone nor placebo had an effect. Similarly, incubation of WBCs with clinically relevant G-CSF concentrations (60 microg/L) for 90 minutes down modulated PSGL-1 expression on neutrophils and enhanced CD11b expression, compatible with a direct PSGL-1 down regulation by G-CSF-induced neutrophil activation. Similar to G-CSF, GM-CSF down regulated PSGL-1 in vitro. Both drugs induced shedding of soluble PSGL-1, supporting the concept that proteolytic cleavage is a potential mechanism of PSGL-1 down regulation on neutrophils. CONCLUSION: G-CSF, but not dexamethasone, down regulates PSGL-1 expression on the surface of neutrophils in humans. This could also partly explain the synergistic effects when both drugs are combined for optimal mobilization of neutrophils for clinical granulocyte transfusion programs.