Prolonged His-Q interval in chronic bifascicular block. Relation to impending complete heart block.
- 1 January 1976
- journal article
- case report
- Published by Wolters Kluwer Health in Circulation
- Vol. 53 (1) , 47-55
- https://doi.org/10.1161/01.cir.53.1.47
Abstract
Although prolonged infra-His conduction time in bifascicular block is suspected of denoting trifascicular disease, adquate documentation is lacking concerning the correlation between lengthened His-Q interval (H-Q) and the risk of development of complete heart block (CHB). H-Q in conducted sinus beats in patients with bifascicular block associated with Mobitz II or intermittent CHB represents the approximation of maximal H-Q prolongation prior to onset of trifascicular block. To assess this relationship between prolongation of H-Q and trifascicular block, His bundle electrocardiography (HBE) was performed in 50 patients with chronic bifascicular block exhibiting Mobitz II block or transient CHB. Mobitz II or episodic CHB was shown in all patients: within two days prior to HBE in 45/50 patients; in 39/50 patients during HBE; and following HBE in five patients. In 49/50 patients H-Q was prolonged (greater than 55 msec) and in 47 this interval was substantially lengthened (65 msec or greater). Since marked H-Q prolongation in conducted sinus beats was documented in nearly all patients with bifascicular block associated with intermittent complete trifascicular block, we conclude that a considerably lengthened H-Q interval in bifascicular block is not only a usual prerequisite but strong evidence, for impending complete heart block.Keywords
This publication has 17 references indexed in Scilit:
- Significance of first degree heart block (prolonged P-R interval) in bifascicular blockThe American Journal of Cardiology, 1974
- Bifascicular block: A clinical and electrophysiologic studyAmerican Heart Journal, 1973
- The magnitude of risk of developing complete heart block in patients with LAD-RBBBAmerican Heart Journal, 1973
- Intraventricular conduction time (H-V interval) during antegrade conduction in patients with heart blockThe American Journal of Cardiology, 1973
- Antiarrhythmic Agents1 IDrugs, 1973
- Patterns and mechanisms of QRS normalization in patients with Wolff-Parkinson-White syndromeThe American Journal of Cardiology, 1971
- Assessment of atrioventricular conduction in left and right bundle branch block using his bundle electrograms and atrial pacingThe American Journal of Cardiology, 1971
- Intraventricular trifascicular blocks. Review of the literature and classificationAmerican Heart Journal, 1969
- Character, cause, and consequence of combined left axis deviation and right bundle branch block in human electrocardiogramsAmerican Heart Journal, 1969
- The electrocardiographic diagnosis of bilateral bundle branch block in relation to heart blockProgress in Cardiovascular Diseases, 1964