Initial experience with the high-density mesh ablation catheter for pulmonary vein isolation.

BACKGROUND

Pulmonary vein isolation (PVI) is usually performed with multiple point-by-point radiofrequency ablation with a second multielectrode circular mapping catheter to validate isolation. We evaluated a 30-mm high-density mesh electrode (HDMA) for mapping and PVI in patients with recurrent atrial fibrillation (AF).

METHODS

In 13 patients (validation group) up to three pulmonary veins (PVs) were targeted with the HDMA. A circular mapping catheter was used to validate PVI. PVI was completed with a CARTO-guided approach (Biosense Webster, Diamond Bar, CA, USA) followed by a voltage remap. In 11 patients (feasibility group) the HDMA catheter was evaluated as a stand-alone mapping and ablation tool.

RESULTS

The diagnostic accuracy of the HDMA catheter to evaluate PVI was 100%. The encircled low-voltage area (<0.15 mV) after HDMA-guided PVI was smaller compared to CARTO-guided PVI. In the feasibility group 76% of the PVs could be isolated. Complete isolation of all PVs was feasible in five patients (45%) with a mean procedure and fluoroscopy time of respectively 180 +/- 39 minutes and 40 +/- 14 minutes. After 1 year 64% of the patients were free of symptomatic AF.

CONCLUSIONS

The HDMA electrode is a reliable mapping tool to validate PVI. The majority of PVs can be isolated, but on a patient basis touch-up ablations are necessary in more than 50% of the cases. Therefore, modifications in catheter design are required. The small area of voltage abatement points to an ostial left atrium-pulmonary vein disconnection. Initial clinical results in a small number of patients are promising.