Nevertheless, access from the coronary venous vasculature may be challenging because of the complex anatomy of the cardiac venous system. Although the distance between the coronary veins and left ventricular myocardium may be significant (up to 20 mm), the range of the ThermoCool electrodes allows reaching the arrhythmia source from the epicardial aspect, making ablation successful. In addition, recent long-term observations from ventricular ablations in the LVS region using a bipolar technique show reduction in unattainable arrhythmias [83].