Introduction

Pulmonary vein isolation (PVI) using radiofrequency (RF) energy is standard of care in patients with drug-refractory atrial fibrillation (AF) but remains a challenging and time-consuming procedure even in experienced hands. A novel bidirectional steerable sheath (Carto Vizigo®, Biosense Webster, Irvine, USA) was introduced allowing its real-time visualization in the 3D-Mappingsystem (Carto 3®, Biosense Webster, Irvine, USA) during ablation.

Aim

This study aimed to assess the acute procedural success of PVI using the visualized sheath and to compare the performance with a matched control group receiving PVI with conventional, non-steerable sheaths.

Methods

All patients between 09/2019 and 02/2021 who underwent PVI using the visualized sheath were included in the study. All received RF-PVI, additional lesions were performed according to the presence of low-voltage zones or left atrial macroreentrant-tachycardia (LAMRT). The patients were followed in our outpatients clinic via 96h-Holter-ECG 3, 6 and 12 months after the procedure. Arrhythmia recurrence was defined as any AF/atrial tachycardia (AT) episode lasting >30s after a blanking period of 3 months. Procedural data were compared to a matched cohort consisting of patients receiving PVI with conventional sheaths.

Results

A total number of 100 patients underwent RF-PVI using the visualized sheath. Mean age was 66.18±10.3 years, 65% were male and 70% suffered of persistent AF. The PVI was the index procedure in 77 patients. Left atrial substrate modification was added in 45 patients (15% septal line, 4% roof line, 8% box-lesion). All procedures were conducted without any major complications. The total procedure duration as well as the total fluoroscopy time and dose were significant longer in the control group than in the testing group (148.95min±33.28 vs. 106.74min±24.36; p<0.001; 10.36min±5.17 vs. 7.38min±2.77; p<0.001 and 1402.56(cGy)*cm²±886 vs. 550.42(cGy)*cm²±546; p<0.001, respectively). The difference between the procedure duration was mainly driven by a prolonged left atrial dwell time (108min±24 vs. 69min±16; p<0.001). During a mean follow-up of 13±5months, the overall procedural success was 92%.

Conclusion

Catheter ablation for AF using the novel visible sheath in conjunction with a 3D mapping system is safe and effective and leads to a relevant decrease of procedure duration and fluoroscopy time and dose during the ablation procedure. The integration of the new device into the clinical workflow for AF ablation under routine conditions was benefitial in terms of procedural parameters, but not for patient outcome.