A comparison between multipolar mapping and conventional mapping of atrial tachycardias in the context of atrial fibrillation ablation.

Background: Activation mapping can be challenging and time-consuming in patients with multiple atrial tachycardias (ATs).

Aims: To compare multielectrode mapping using a dedicated mapping catheter - PentaRay (Biosense Webster Inc.) - and the conventional technique for mapping ATs in the context of atrial fibrillation (AF) ablation.

Methods: All procedures where PentaRay mapping of AT were used - after or during persistent AF ablation - were analysed. These were compared to a historical group - using conventional mapping.

Results: A mean of 449±520 points within 14±6min were acquired per AT in the PentaRay group (n=17) versus 42±18 points (P<0.0001) within 33±25min (P=0.04) in the conventional group (n=17). All 25 AT isthmuses were easily identified and ablated in the PentaRay group (100%) versus 20/23 (87%) in the conventional group (P=0.056). The ablation time was shorter in the PentaRay group (760±540 vs 1347±962 s; P=0.037). However, procedure and fluoroscopy times were not significantly different between the PentaRay and conventional groups: 253±77 vs 267±73min (P=0.80) and 13.1±8.0min vs 15.1±10.0min (P=0.98), respectively. Recurrence occurred in less patients in the PentaRay group (0 vs 23.5%; P=0.033) during a mean follow-up of nearly 1 year.

Conclusion: In patients with multiple ATs, multielectrode PentaRay mapping was faster than the conventional technique, with less radiofrequency delivery and a better mid-term outcome.