[Recurrent ventricular tachycardias following myocardial infarction: linear ablation strategy using an electroanatomical mapping system].

BACKGROUND AND AIM OF STUDY

The implantable cardioverter defibrillator (ICD) is the therapy of choice for patients with ventricular tachycardia (VT) after myocardial infarction. In some patients frequent ICD shocks occur, often resulting in clinical problems, if antiarrhythmic drugs insufficiently suppress them. Our aim was to describe electro-anatomical mapping and ablation techniques in patients with VTs, in which conventional strategy treatments have failed.

PATIENTS AND METHODS

17 patients (69.5 +/- 8 years, 12 male) were included. During 3 months before ablation the number of ICD shocks was 21 +/- 8 (mean +/- SD). Using an electro-anatomical mapping system (CARTO), activation mapping was performed in 12 patients during hemodynamically tolerable, stable VT. In 5 cases with "non-mappable" VT only voltage mapping during sinus rhythm was obtained. The aim was to characterize the underlying scar tissue precisely in order to modify the substrate with an individual strategic linear lesion, thus preventing re-induction of VT.

RESULTS

Procedure time was 184 +/- 9 minutes, fluoroscopy time totalled 19 +/- 9 minutes. Lesion lines were established with 13 +/- 9 ablation pulses. In 15 patients (88 %) acute ablation of the VT was successful. During a follow-up of 8 +/- 7 months, 2 patients had a recurrence of the VT. Two patients developed a VT with a different morphology. In another case ventricular fibrillation occurred. No major complications were observed.

CONCLUSION

Electro-anatomical mapping combined with an individual linear ablation strategy is a safe and effective method to prevent symptomatic VT in patients after myocardial infarction.