[Endo- and epicardial catheter ablation preventing ventricular tachycardia: impact of substrate modification]

Challenges encountered during catheter ablation of ventricular tachycardia (VT) include hemodynamic instability and lack of inducibility. Recent approaches guided by electroanatomic mapping demonstrated the feasibility of VT ablation during sinus rhythm. We analyzed the data from 40 consecutive patients who were referred to the Elisabethinen Hospital Linz for VT ablation. Ablation target sites were identified by using pace-, electroanatomic, and specific VT-related potential mapping. All clinical VTs were eliminated by catheter ablation in 38 of 40 patients within 43 procedures. Epicardial mapping and ablation via a subxiphoid percutaneous access was necessary in 3 patients. In total, 4 out of 14 patients with a history of frequent ICD shocks received additional ICD discharges during follow-up (n = 2:ICD-shock; n = 2:antitachycardia-pacing). Combining pace-, activation-, entrainment-, and substrate-mapping is useful for VT prevention by catheter ablation. A subxiphoid percutaneous approach is useful in some patients for extensive mapping and ablation at the epicardial surface of the heart.