Focus Location

iDevice icon Ventricular (RVOT) Focus Ablation

Having failed to control her symptoms with medical therapy, she was offered and accepted attempted ablation of her RVOT focus.

A composite EP surface ECG showing the intrinsic bigeminal rhythm on the left (25mm/s paper speed), with a pace-map on the right (50mm/s paper speed; pacing from Abl2 electrode) is given below.

Is the ablation cather (Abl2) correctly located at the RVOT focus?

Remember that a 12 out of 12 surface ECG match is required between the intrinsic ventricular rhythm (i.e. ectopic beats) and the pace-map to confirm co-location.

Quick Question

Given that lead I is not a match between the intrinsic ectopic and the pace-train, with a positive QRS on the intrinsic ECG and negative on the paced beat, the ablation (pacing) catheter needs to be moved to try and improve the ECG match.

The focus is known to be in the RVOT on the basis of the surface ECG.

Is the following statement true or false? 

In order to improve the surface ECG match, the ablation catheter needs to be moved to the left of the patient (i.e. towards the septum).

True False     

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