Gold tip ablation facilitates acute pulmonary vein isolation. A prospective randomized pilot study

Abstract

Background: Pulmonary vein isolation (PVI) is the standard treatment for drug-refractory paroxysmal atrial fibrillation (PAF). Effective lesion formation is determined by ablation power, ablation time and contact force enabling a better energy transfer into tissue. Moreover, animal experiments suggest that gold tip catheters may provide larger lesion volume by enabling larger energy deployment avoiding tip electrode overheating. Objective: To compare the acute procedural performance of an irrigated gold tip catheter (Alcath Flux G Extra, Biotronik; Au) with an irrigated Pt/Ir catheter (Alcath Flux, Biotronik; Pt). Methods: Twenty patients (11male, mean age 62±11 yrs) with a history of PAF were enrolled and underwent PVI in a prospective randomized fashion in two groups. After double transseptal access and 3D mapping (EnSite) circumferential PVI was performed using the Au or Pt catheter at a maximum power of 40W and a flush rate of 17-25ml/min. Maximal tip temperature was set at 43°C. Acute procedural endpoint was complete electrical PVI proven by a circular mapping catheter. Results: Acute electrical PVI was achieved in all patients. The total procedure time was 81±13 and 120±35 min in the Au and Pt group, respectively (p=0.01). Total ablation time was significantly shorter in the Au group 963±276 s versus 2085±1137 (p=0.01). Ablation energy and mean catheter tip temperature were significantly lower in the Au group 28682±8129 Ws versus 47974±23966 Ws (p=0.01) and 47±2°C versus 41±2 °C. The mean ablation power delivered was 30±2 with Au and 23±4 with Pt, respectively (p=0.0002). Conclusion: Gold tip ablation demonstrated superior acute efficacy expressed by shorter procedure times due to more efficient ablation power delivery with less catheter tip heating. Long-term results will be presented.