Isthmus Guided vs Anatomical Linear Ablation in the Treatment of Scar Related Atrial Tachycardia

Catheter based mapping of the electrical signals in the heart during atrial tachycardia can identify areas that require ablation in order to treat the arrhythmia. There are numerous methods by which to map atrial tachycardia. Isthmus guided ablation using Ripple Mapping is one such method, and has recently been demonstrated to improve diagnostic accuracy of mapping and therefore improve acute procedural outcomes (termination of the tachycardia).

However, it is not known if improved acute procedural outcomes translate into long-term benefits for patients. At present, the recurrence rate following atrial tachycardia ablation is near 30%. We hypothesise that isthmus guided ablation using Ripple Mapping can reduce long-term recurrence following ablation as improved diagnostic accuracy of mapping can lead to more targeted, less extensive, ablation.

Patients referred for catheter ablation of atrial tachycardia will be randomised to undergo the procedure by isthmus targeted approach using Ripple Mapping or conventional approach using local activation time. Otherwise, the catheters used to perform the mapping and ablation will be the same in both groups. After the procedure, follow up will occur at 1 year with a further Holter Montior. Any arrhythmia recurrence will be documented and the two arms will be compared for acute success, 12 month success, ablation required and procedure time.