Comparison of 3 RF Delivery Modes of the QDOT Catheter for Paroxymal Atrial Fibrillation (AF) Ablation

Pulmonary vein isolation (PVI) is the main treatment of paroxysmal and persistant atrial fibrillation.

PVI is achieved by point-by-point radiofrequency ablation that creates flexible lesion set within targeted area.

PVI using standard ablation catheter with limited power (50W) have been described in case series with favorable efficacy and safety.

QDOTMicro™ is a radiofrequency ablation catheter that incorporates advanced, high-energy ablation, improved temperature monitoring, optimized irrigation, and higher signal resolution.

QDOT Micro™ provides several options regarding radiofrequency administration :

• Q-MODE : provides high power short duration (HPSD) unitl 50W radiofrequency,
• Q-MODE+ : provides very high power very short duration (vHSPD) until 90W radiofrequency,
• Hybrid Q-MODE/Q-MODE+ : is a combination of two methods. In our experience, stability is a prerequisite for PVI with QDOT Micro™.

Small series have described encouraging results (85% isolation, unpublished data) with stabilization tools such as low-volume ventilation or apnea, high-rate simualtion, Vizigo bi-directional sheath (Vizigo™).

Recently, preliminary animal data argue in favor or reducing the interpoint distance with QDOT™.

To date, there is no study comparing the 3 options of radiofrequency delivery. The aim of our study is to prospectively compare the efficacity and safety of the 3 options of radiofrequency delivery with QDOT Micro™, with systematic use of catheter stabilization tools and tighter lesions.

The same device is used in all three randomisation groups. The difference between the intervention is the intensity of the radiofrequency applied.

Inclusion criteria

• Patient aged 18 or over
• First atrial fibrillation ablation
• Paroxysmal atrial fibillation defined as atrial fibrillation lasting less than 48 hours
• Early atrial fibrillation defined as atrial fibrillation lastiing between 7 days and 3 months
• At least one episode of atrial fibrillation in the year preceding study entry
• Patient affiliated to a health insurance

Exclusion criteria

• History of atrial fibrillation ablation (surgery or catheter)
• Documented left atrial thrombus
• Left atrial (LA) diameter > 60mm / LA area > 35cm2 / Left atrial volulme index (LAVI) > 45ml/m2
• N/STEMI replacement or angioplasty or valve within 3 months prior to registration
• Any contraindication mentioned in the instructions for use of the QDOT MICRO™ bidirectional navigation catheter
• Patient unable to understand study information
• Patient deprived of liberty by judicial or administrative decision