A RAndomized Trial to compare the acute reconnection after pulmonary vein ISolation with Laser-BalloON versus radiofrequency Ablation: RATISBONA trial.

INTRODUCTION: Dormant conduction and acute reconnection in the pulmonary veins (PV) during a PV isolation can be detected by performing an adenosine provocation test (APT). Visually guided laser balloon ablation (VGLB) creates deep transmural lesions, thus causing less acute reconnection. This study compared the acute PV reconnection rate after isolation with VGLB or with RF using an APT. METHODS AND RESULTS: Patients with paroxysmal AF were randomized to PVI with the VGLB or RF ablation. Each PV underwent an APT at least 20 minutes after successful isolation with injection of 18 mg adenosine. Primary endpoint was the difference between the two ablation methods regarding acute PV reconnection rate detected with APT. A total of 50 patients were randomized into the study (25 VGLB). The basic characteristics and mean procedure time were not different between the two groups. Note that 96% of the 97 targeted PVs in the VGLB group and 98% of the 96 targeted PVs in the RF group could be isolated (P  =  0.41). APT was performed at similar times (after 28 minutes in VGLB-arm vs. after 31.5 minutes in RF-arm; P  =  0.12). Significantly less PVs were reconnected during APT in the VGLB group than in the RF group (10 PV [10.8%] vs. 29 PV [30.9%]; P  =  0.001). CONCLUSION: The acute PV reconnection rate is significantly less after PVI with VGBL than with RF. The clinical significance of this apparently better procedural efficiency of the VGBL ablation should be assessed with new randomized studies looking at AF recurrence.

Unmasking the dormant pulmonary vein conduction with adenosine administration after pulmonary vein isolation with laser energy.

AIMS: The isolation of the pulmonary veins (PVs) is the mainstay of atrial fibrillation (AF) ablation, which with current ablation techniques can be achieved in almost all cases. Reconnection of PVs constitutes the most frequent cause of AF recurrence. Visually guided laser balloon ablation (VGLA) is a novel system with very high rate of persistence of pulmonary vein isolation (PVI) three months after the first procedure shown in preclinical and clinical studies. We aimed to determine the acute efficiency of the laser energy during PVI with the help of adenosine provocation. METHODS AND RESULTS: Twenty-six patients (19 male; mean age 64 ± 9 years) with symptomatic paroxysmal AF were included in the study. Pulmonary vein isolation was performed using the VGLA system. After successful PVI, we studied the effects of intravenous adenosine (18 mg) on activation of each PV at least 20 min after PVI. A total of 104 PVs were targeted. The balloon catheter could not be placed in two PVs. Of the remaining 102 PVs 99 (97% of the ablated PVs) could be successfully isolated. Adenosine was administered for each isolated PV in 25 patients. Only six PVs (6.7%) in five patients (20%) showed a PV reconnection during adenosine provocation. CONCLUSION: Pulmonary vein isolation with VGLA is a feasible technique for PVI with a very effective acute lesion formation. The clinical significance of this low reconnection rate has to be determined.