Impact of real-time contact force and impedance measurement in pulmonary vein isolation procedures for treatment of atrial fibrillation

Pulmonary vein isolation (PVI) is an established procedure to treat atrial fibrillation (AF). New techniques are necessary to improve procedural parameters like shortening of procedure duration. Real-time contact force (CF) catheters are new tools aiming to improve PVI by optimizing electrode-tissue contact and generating more effective lesions. Objective of this study was to investigate the influence on procedural parameters and clinical outcome by using a CF catheter for PVI. PVI was performed on 67 consecutive patients using a CF catheter (n = 32) or a standard ablation catheter (SAC, n = 35). Study endpoints included number of energy applications, impedance drop, fluoroscopy time, and left atrial (LA) procedure time and freedom from AF after 6 and 12 months. Procedural endpoint was reached in all patients with a similar clinical outcome (freedom from AF) in both groups 6 months (62.9 vs. 62.5 %) and 12 months post PVI (59.4 vs. 62.9 % in CF vs. SAC group, respectively). However, CF-guided ablation resulted in a greater fall of impedance (6.58 +/- A 0.33 vs. 9.09 +/- A 0.53 Omega, *** p < 0.001), lower number of energy applications (44.20 +/- A 3.67 vs. 34.06 +/- A 3.11, * p < 0.05), reduction of LA procedure time (95.52 +/- A 7.35 vs. 78.08 +/- A 7.23* min) and a significant reduction of fluoroscopy time (51.4 +/- A 3.3 vs. 33.0 +/- A 2.7*** min). In addition, a detailed analysis showed a significant correlation between quantitative impedance drop and amount of CF applied, suggesting more efficient lesion creation by CF-guided ablation. Use of CF catheters in PVI has a beneficial effect on procedural parameters, probably by improving efficacy of transmural lesion formation.