Unusual QRS pattern in pervenous right ventricular pacing
Lee, W.S.; Lee, D.F.; Chen, F.T.; Wu, T.C.
Journal of the Formosan Medical Association 85(9): 898-904
1986
ISSN/ISBN: 0371-7682 PMID: 3470435 Document Number: 283292
Four cases of unusual QRS pattern resembling right bundle branch block pattern were found on 12-lead electrocardiograms after implantation of permanent transvenous ventricular pacemaker. All of these showed dominant R wave in leads V1 and V2, and QS wave in leads V3 to V6. Three cases had wide and slurred R wave and 1 case had QS wave in lead 1; their main QRS vectors were upward and slightly formed. Recording the precordial leads V1 and V2 one intercostal space below the usual space, resulted in inscription of a QS complex, that is the usual left bundle branch block pattern that is seen ordinarily in leads V1 and V2 recorded in the 4th intercostal space, whereas recording the leads 1 space higher than usual enhanced the height of the R wave. This phenomena may be related to the relative position of the precordial leads against the heart by main QRS vector.