Click on image to view larger version.

Figure 4 Example of a successful ablation of an idiopathic ventricular tachycardia (VT) from the great cardiac vein via the coronary sinus. (A) The electrogram recorded from the ablation catheter precedes the QRS complex by 45 ms. (B) A 12-lead surface ECG of the idiopathic VT is shown at the left half of the panel. On the right half, a perfect pacemap obtained at the successful ablation site is shown. (C and D) Coronary sinus (CS) electroanatomic activation maps during idiopathic VT are shown. Red color indicates the earliest activation time. The dark red dot represents the successful ablation site (ABL) in the great cardiac vein. AV = aortic valve area; CSO = coronary sinus ostium; GCV = great cardiac vein. (E and F) Radiograms show the successful ablation site. LAD = left anterior descending artery; LCX = left circumflex artery. Other abbreviations as in Figures 2 and 3.