[Idiopathic ventricular tachycardia responsive to verapamil. Presentation of 3 cases and review of the literature].
Recently a unique clinical entity has been suggested in subjects without apparent heart disease presenting with recurrent ventricular tachycardia (VT) characterized by RBBB + LAH electrocardiographic pattern, relatively slow rate, induction by atrial stimulation, and interruption by verapamil. According to these characteristics, three cases (2 M and 1 F, aged 18, 33 and 66 years) are presented in this study. They have had palpitations from one to twenty years, but not syncopal episodes. During VT the cycle length ranged from 300 to 480 msec. VT was terminated both by verapamil and by ajmaline. VT was inducible in 3/3 cases by incremental atrial pacing when cycle length of pacing became similar to that of spontaneous VT; in 2/3 cases VT was induced by programmed right atrial stimulation and in 2/3 cases by programmed ventricular stimulation. Serial electrophysiological studies for pharmacological and therapeutic evaluation applied to 1/3 cases showed: amiodarone given orally (200 mg/die) for two months prevented the induction of VT while verapamil, propranolol, mexiletine, and propafenone tested intravenously were ineffective. In the remaining two patients amiodarone, tested only intravenously, was not effective to prevent the induction of VT but lengthened its cycle length. All patients received amiodarone orally (200 mg/die) and were followed for 2,7 and 8 years respectively. Two of them had no more episodes of VT and one, while asymptomatic, continued to present with. The electrophysiological mechanism of this form of VT cannot be identified with certainty, but many data suggest a reentry in the posterior fascicle of left bundle branch as the most probable mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)
D000293:Adolescent; D000328:Adult; D000368:Aged; D000404:Ajmaline / Q000627:therapeutic use; D000638:Amiodarone / Q000627:therapeutic use; D002037:Bundle-Branch Block / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D013610:Tachycardia / Q000188:drug therapy* / Q000503:physiopathology; D014700:Verapamil / Q000627:therapeutic use*
D000404:Ajmaline; D014700:Verapamil; D000638:Amiodarone
Tachicardia ventricolare idiopatica sensibile al verapamil. Presentazione di tre casi e revisione della letteratura.