Ventricular tachycardia idiopathic

Ventricular tachycardia (VT) is defined by three or more repetitive PVCs occurring at a rate greater than 100 beats/min. It occurs most commonly in acute myocardial infarction (MI) other causes are severe electrolyte abnormalities (e.g., hypokalemia), hypoxemia, and digitalis toxicity. The chronic recurrent form is almost always associated with underlying organic heart disease (e.g., idiopathic dilated cardiomyopathy or remote MI with left ventricular [LV] aneurysm). 

Verapamil is useful for slowing the ventricular response to atrial tachyarrhythmias, such as atrial flutter and fibrillation. Verapamil is also effective in arrhythmias supported by enhanced automaticity, such as ectopic atrial tachycardia and idiopathic left ventricular tachycardia. 

Schmitt C, Brachmann J, Schols W, Beyer T, Kubler W. Proarrhythmischer Effekt von Ajmalin bei idiopathischer ventrikularer Tachykardie. [Proarrhythmic effect of ajma-line in idiopathic ventricular tachycardia.] Dtsch Med Wochenschr 1989 114(3) 99-102. 

Most but not all forms of recurrent ventricular tachycardia occur in patients with extensive heart disease. Ventricular tachycardia occurring in a patient without heart disease is sometimes referred to as idiopathic ventricular tachycardia and may take several forms. " Fascicular tachycardia arises from a fascicle of the left bundle branch (usually posterior) and usually is not associated with severe underlying heart disease. Calcium channel blockers (but not adenosine) are effective in terminating an acute episode of fascicular ventricular tachycardia. Ventricular outflow tract tachycardia (usually originating from the right ventricular outflow tract and thus abbreviated RVOT) originates from near the pulmonic valve (or uncommonly the aortic) and also occurs in patients with normal LV without discernible cardiac disease. Unlike other forms of ventricular tachycardia, RVOT... 

Ablation may treat bundle-branch reentry and fascicular forms of ventricular tachycardia effectively (142-144). Ablation of Purkinje fibers may reduce the risk of idiopathic ventricular fibrillation initiated by a PVC (76) and some forms of ventricular tachycardia (145). Substrate modification can reduce specific forms of recurrent monomorphic ventricular tachycardias in patients with structural heart disease (138,146-149), particularly if the patient is having storms of tachycardia Therefore, occasionally, ablation performed during electrophysiology testing can modify the ventricular tachycardia recurrences... 

Ablation of ventricular tachycardia with complete cure is possible for idiopathic right ventricular outflow tract tachycardia, for idiopathic left ventricular tachycardia from the apical septum, for ventricular tachycardia due to Tetralogy of Fallot, and for bundle branch reentrant tachycardias. Ablation can be effective for ventricular tachycardia with other associated structural heart disease, but no evidence indicates that it will decrease the risk of death. 

---