Real world data on the use of the QDOT Micro catheter for atrial fibrillation ablation across different centers in Europe: the AIR HPSD multicentric Registry

The QDOT Micro catheter (Biosense Webster, Inc CA) enables the ablation in the Qmode+ modality (90 W for 4 sec) and/or in the Qmode modality, 50 W ablation index (AI)-guided. Several studies have described that both modalities of very high-power short duration (vHPSD) ablation improve procedural efficiency without compromising the efficacy and the safety of the pulmonary vein isolation (PVI), however they were from single centers or had a limited sample size. To date, data from large multicentric registries are still lacking.

We aimed to report real world data on acute efficacy and safety from a large cohort of atrial fibrillation (AF) patients ablated in the AIR HPSD registry.

The AIR HPSD Registry is a multicentric study including AF patients undergoing their first PVI procedure by mean of the QDOT Micro catheter across 22 European centers. The ablation modality (hybrid/ Qmode+) and the type of anesthesia were left to operators’ preference. The main outcomes investigated were: the rate of PVI, the rate of first pass isolation (FPI), the procedural and 30-days complications.

Overall, 917 patients with a mean age of 62±10 years were enrolled, of these 28% were women and 70% had paroxysmal AF. As for the comorbidities, 45% were hypertensive, 9% had diabetes mellitus, 3% chronic kidney disease and 11% ischemic heart disease. In 44% of patients exclusively the Qmode+ modality was adopted, 25% of patients were ablated under general anesthesia (GA), while the remaining was ablated under conscious/deep sedation. The PVI was reached in all patients and in 25% of patients the cavo-tricuspid isthmus ablation was additionally performed. The rate of FPI was 75%. The procedural time was 106±42 min while the fluoroscopy time was 5,4±7,2 min. The overall rate of complication was 1,4%: pericardial effusion/pericarditis (38%), vascular complications (23%), cardiac tamponade (15%) and 8% air embolism. Furthermore, 2 patients experienced pulmonary vein stenoses at 30-day follow up.

The real world data from the AIR HPSD Registry show that the vHPSD ablation performed in a large cohort of AF patients by mean of the QDOT Micro catheter leads to high rates of acute efficacy with a good safety profile.