Single-centre experience with an 8-mm tip catheter for radiofrequency catheter ablation of outflow tract ventricular...

Radiofrequency ablation (RFA) of outflow tract ventricular ectopic beats (OTVEBs) can be performed using a 4-mm or externally-cooled tip RFA catheter, but no data are available concerning the safety and efficacy of a large-tip (8-mm) catheter.

To evaluate the feasibility of using an 8-mm tip catheter in patients with OTVEBs.

In this prospective cohort study, the 8-mm tip catheter was tested in patients who were referred to our centre for RFA of symptomatic OTVEBs.

The mean age of the 16 patients recruited between September 2008 and March 2010 was 53±18 years and 56.3% were male. Mean left ventricular ejection fraction was 62±9%, mean ventricular ectopic beat width was 144±21 ms, and all patients had left bundle branch block. Fourteen patients had inferior axis QRS morphology and two had superior. The main symptoms were palpitations and pre-syncope. RFA parameters were: procedure time 94±35 min; duration of application 11±10 min; impedance 81±12 Ω; temperature 50±5 °C; and power 46±17 W. RFA succeeded in 15 over 16 patients (93.8%); and recurrence was seen in one patient after a mean follow-up time of 11±6 months. No complications were noted.

This preliminary study suggests that an 8-mm tip catheter may represent an alternative for RFA in patients with OTVEBs in whom a 4-mm tip was not successful. Larger randomized studies are therefore warranted.