Necessity of epicardial ablation for ventricular tachycardia after sequential endocardial approach

- Necessity of epicardial ablation after a thorough endocardial approach by a sequential ablation protocol in SHD.
- High acute and long-term success rates by sole endocardial ablation regarding VT freedom with a maximum risk reduction.
- Significance of conventional mapping and stim-QRS interval for determination of ablation sites, termination and success.

BackgroundCatheter ablation (CA) of ventricular tachycardia (VT) is an important treatment option in patients with structural heart disease (SHD) and implantable cardioverter defibrillator (ICD). A subset of patients requires epicardial CA for VT.ObjectiveThe purpose of the study was to assess the significance of epicardial CA in these patients after a systematic sequential endocardial approach.MethodsBetween January 2009 and October 2012 CA for VT was analyzed. A sequential CA approach guided by earliest ventricular activation, pacemap, entrainment and stimulus to QRS-interval analysis was used. Acute CA success was assessed by programmed ventricular stimulation. ICD interrogation and 24 h-Holter ECG were used to evaluate long-term success.ResultsOne hundred sixty VT ablation procedures in 126 consecutive patients (114 men; age 65 ± 12 years) were performed. Endocardial CA succeeded in 250 (94%) out of 265 treated VT. For 15 (6%) VT an additional epicardial CA was performed and succeeded in 9 of these 15 VT. Long-term FU (25 ± 18.2 month) showed freedom of VT in 104 pts (82%) after 1.2 ± 0.5 procedures, 11 (9%) suffered from repeated ICD shocks and 11 (9%) died due to worsening of heart failure.ConclusionsDespite a heterogenic substrate for VT in SHD, endocardial CA alone results in high acute success rates. In this study additional epicardial CA following a sequential endocardial mapping and CA approach was performed in 6% of VT.Thus, due to possible complications epicardial CA should only be considered if endocardial CA fails.