DISCUSSION
Catheter ablation is a very effective and demanding technique in the treatment for cardiomyopathy patients with VT storms, especially those with frequent ICD shocks. However, those who were failed by combined endocardial and epicardial ablation are a unique population with very high mortality. Searching for solutions to control VTs in such tough patients is rather important. We report our experience of direct RF ablation with intramyocardial ethanol injection via surgical approach to treat the patients with recurrent VT despite multiple endocardial and/or epicardial ablations. The key findings of this study are as follows: (1) in some patients with non-ischemic cardiomyopathy, VTs were of true intramural origin which explain their refractory property to both endocardial and epicardial ablation (Supplementary Figure 2); (2) surgical RF ablation allowed manual pressure of the catheter against the epicardium, yielding more effective lesions than percutaneous epicardial ablation; (3) intramural ethanol injection produced homogenized tissue necrosis and was a safe and effective strategy for VT elimination.