Co-Author(s):
Stefania Riva, MD
Francesca Pizzamiglio, MD
Maria Antonietta Dessanai, MD
Valentina Ribatti, MD, PhD
Giulia Vettor, MD
Massimo Moltrasio, MD
Claudio Tondo, MD, FESC, FHRS
Centro Cardiologico Monzino IRCCS University of Milan
Via Parea 4 Milano
Introduction | Objectives: Pulmonary vein isolation (PVI) is the cornerstone of catheter-based therapy for patients(Pts) with atrial fibrillation (AF). Single-shot techniques were introduced to improve the procedure. A new multi-electrode radiofrequency balloon catheter (RFB) provides PVI with its 10 irrigated, flexible gold electrodes. The concurrent use of a 10-pole circular diagnostic catheter provides real-time PV recordings. We analyzed time-dependent changes in procedural parameters, acute success, complication rates during our initial experience in subjects with drug refractory, symptomatic, paroxysmal AF.
Methods: 6 patients (age 63.5±6,8 yrs, 33.3% male) underwent PVI using the RFB under conscious sedation. Esophageal temperature monitoring and phrenic nerve pacing were performed in all patients. Based on animal Lab and first human experiences, baseline impedance (90-110) and baseline temperature (< 31C°) were set as indicators of optimal electrode-tissue contact. Accordingly, contiguous lesion formation when simultaneously ablating from adjacent electrodes were strongly identified by impedance drop and temperature rise. Intracardiac echocardiography confirmed optimal balloon positioning and stability during RF delivery. Radiofrequency energy was delivered simultaneously from all electrodes, up to 20 s posteriorly and 60 s anteriorly.
Results: 8.3±4.82 applications were delivered per patient; PVI was achieved in 100% of the 23 targeted PVs. An example of the balloon positioning both on Carto system and on echo is shown in Figure 1. The balloon dwell time was 37.5±24.5 min. The overall procedure time was 68.3±32.9 min, and the fluoroscopy time was 12.3±5.2min. The first-pass isolation was achieved in 79.6% of the assessed PVs; with additional RFB applications to the remaining 5 PVs, all PVs were isolated. Mean time to isolation was 17.5+ 10.6 sec, obtained in all cases combining the recordings from the decapolar catheter and the balloon electrodes. Acute reconnection was provoked in only 2 PVs. No acute or delayed complications occurred.
Conclusions: This preliminary experience demonstrated a remarkable acute safety profile and effectiveness of the new RFB.
AFS 2021-48