The right ventricular tachycardias

A variety of tachycardias originate from the right ventricle or use right v entricular structures as part of their circuit. They are characterized by a left bundle branch block pattern. Many of these tachycardias are relativel y easy targets for radiofrequency catheter ablation. Ventricular tachycardi a (VT) is the most common manifestation of arrhythmogenic right ventricular dysplasia, an often familial disease that can cause sudden death. Catheter ablation, antiarrhythmic drugs, or an implantable cardioverter-defibrillat or may be used as therapy. Idiopathic right ventricular tachycardia has a b enign course. It most often arises from the septal region of the right vent ricular outflow tract. II commonly presents as nonsustained, repetitive mon omorphic VT. The success rate of catheter ablation is greater than 90%. Bun dle branch reentry occurs in patients with cardiomyopathy and His-Purkinje disease. It uses the right bundle branch anterogradely and the Ic ft bundle branch retrogradely. The QRS is very similar during VT and sinus rhythm. I t can be cured by catheter ablation of the right bundle branch. VT seldom o riginates from the right ventricle in patients with coronary artery disease , idiopathic cardiomyopathy or myocarditis. Atriofascicular (so-called Maha im) fibers can sustain antidromic AV reentrant tachycardia. They represent an accessory AV node and His-Purkinje-like conduction system with atrial in sertion in the right free wall near the tricuspid annulus and distal insert ion directly into the right bundle branch. The accessory connection is abla ted at the level of the tricuspid ring.