Successful Radiofrequency Catheter Ablation of Incessant Ventricular Tachycardia with a Delta Wave-like Beginning of the QRS Complex.

Ventricular tachycardia with a delta wave-like beginning of the QRS complex is considered to be refractory to endocardial catheter ablation because it originates from the epicardial region. A 45-year-old woman had incessant ventricular tachycardia with a delta wave-like beginning of the QRS complex which was resistant to several antiarrhythmic drugs. The origin of the arrhythmia was at the mitral annulus on the antero-lateral left ventricular wall. The earliest endocardial activation preceded the QRS complex by 18 msec. After 7 sec of endocardial radiofrequency application ventricular tachycardia was terminated. During a 2 year follow-up ventricular tachycardia did not recur and only small numbers of premature ventricular contractions (< 100/day) were noted. VT with delta wave-like QRS morphology which originates from the basal region of the ventricle may be treated successfully with radiofrequency catheter ablation using an endocardial approach.