Cardiologia Croatica, Vol. 6 No. 12, 2011.
Other
Bundle branch reentrant ventricular tachycardia – Ventricular tachycardia circulating through the branches – Two case studies.
Vedran Velagić
; University Hospital Centre Zagreb, Zagreb, Croatia
Davor Puljević
; University Hospital Centre Zagreb, Zagreb, Croatia
Abstract
Bundle branch reentrant ventricular tachycardia (BBRVT) is a rare form of long-term monomorphic ventricular tachycardia (VT), which predominantly occurs in patients with severe, primary dilated cardiomyopathy. Since this is a fast frequency VT resulting in hemodynamic instability, presyncope and syncope are common presenting symptoms. In the basic ECG in patients with this arrhythmia we find intraventricular disorders of conduction in type left bundle branch block (LBBB) and often PQ prolongation. Also, VT is usually of LBBB morphology, with heart rate over 200/min, while QRS morphology does not significantly differ in sinus rhythm and the arrhythmia itself. These characteristics of the patients and the tachycardia should make us consider of this special type of tachycardia. Definitive diagnosis is made by electrophysiological study to prove that a circular mechanism of tachycardia uses bundle of His and the left and right branch of the conducting system of the heart. Prolonged HV interval as a marker of slowed conduction through the bundle of His and more distal parts of the conducting system is one of the main characteristics of this tachycardia. The ablation of right bundle branch is curative in this arrhythmia. The most common complication of ablation is a total AV block that occurs in 10-30% of cases, which requires the implantation of permanent heart electrostimulator. Due to the basic disease of the heart and the possibility of other types of VTs, these patients show after successful ablation the indication for implantation of cardioverter-defibrillator for primary prevention of sudden cardiac death. Here we present two recent cases of BBRVT.
Keywords
ventricular tachycardia; left bundle branch block; electrophysiological study
Hrčak ID:
74635
URI
Publication date:
15.11.2011.
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