Aims: To analyse procedural results and clinical outcome of paroxysmal atrial fibrillation (AF) ablation using the 30 and 35 mm high-density mesh ablator (HDMA, Bard Electrophysiology).
Methods and results: Sixty-four consecutive patients were ablated with the HDMA catheter (26 with the 30 mm, 38 with the 35 mm device). If pulmonary vein (PV) isolation was unsuccessful, ablation was continued using a conventional 4 mm ablation catheter. Success was defined as freedom of AF at 6 months after a single procedure without antiarrhythmic drugs. PV isolation could be obtained in 84/106 (79%) PVs in the 30 mm group vs. 149/153 (97%) PVs in the 35 mm group (P < 0.001). All non-isolated veins were successfully isolated with the conventional 4 mm ablation catheter. Freedom of AF at 6 months was 19% in the 30 mm group vs. 18% in the 35 mm group (P = NS). During a repeat procedure in 19 patients, 69% of the PVs were reconnected with an incremental LA-PV delay of 11 ± 15 ms compared with baseline.
Conclusion: (i) Compared with the 30 mm, the 35 mm HDMA catheter proves to be more efficient in obtaining acute pulmonary vein isolation, (ii) despite these promising procedural results, the clinical outcome is disappointing and (iii) the high reconnection rate and the limited delay in PV potentials suggest that PV isolation with the HDMA catheter is not permanent.