Incessant Ventricular Tachycardia with a Right Bundle‐Branch Block Pattern and Left Axis Deviation Abolished by Catheter Manipulation

Abstract
A 22-year-old man underwent electrophysiological evaluation for incessant wide QRS complex tachycardia with a pattern of right bundle-branch block and left axis deviation. The right and left ventricles were enlarged and hypokinetic consistent with dilated cardiomyopathy. Ventricular tachycardia was diagnosed by demonstrating capture and fusion beats, atrioventricular dissociation, and His potential activation that began after the onset of each QRS complex. Atrial extrastimuli and rapid atrial pacing failed to terminate the tachycardia and, although ventricular stimulation was successful, the tachycardia spontaneously restarted after one or two sinus beats. The tachycardia was unexpectedly abolished during catheter manipulation in the left ventricle and has not recurred during three-years of follow-up. The picture of a cardiomyopathy resolved. The ease with which the tachycardia was abolished by catheter manipulation implicate a therapeutic potential for catheter ablation of this type of tachycardia.