Bundle branch aberrancy

Right bundle-branch aberrancy will have a triphasic rSR configuration in V and a triphasic qRS configuration inVg. 

Comparing PVC with right bundle-branch aberrancy... 

Left bundle-branch aberrancy will have a narrow R wave with a quick downstroke in leads V, and Vj, and no Q wave in Vg. 

Hypersensitivity or idiosyncrasy to quinidine or other cinchona derivatives manifested by thrombocytopenia, skin eruption or febrile reactions myasthenia gravis history of thrombocytopenic purpura associated with quinidine administration digitalis intoxication manifested by arrhythmias or AV conduction disorders complete heart block left bundle branch block or other severe intraventricular conduction defects exhibiting marked QRS widening or bizarre complexes complete AV block with an AV nodal or idioventricular pacemaker aberrant ectopic impulses and abnormal rhythms due to escape mechanisms history of drug-induced torsade de pointes history of long QT syndrome. 

Crijns HJ, Kingma JH, Gossehnk AT, Lie K. Comparison in the same patient of aberrant conduction and bundle branch reentry after dofetilide, a new selective class III antiarrhythmic agent. Pacing Clin Electrophysiol 1993 16(5 Pt 1) 1006-16. 

Bundle branch block and aberrant conduction were noted in children during halothane anesthesia (8). 

Ventricular aberrancy, or aberrant ventricular conduction, occurs when an impulse originating in the sinoatrial node, atria, or atrioventricular junction is temporarily conducted abnormally through the bundle branches. The abnormal conduction results in a bundle-branch block, usually because electrical impulses arrive at the bundle branches before the branches have been sufficiently repolarized. 

If the beat is triphasic, similar to a right bundle-branch block, suspect SVT with aberrancy. 

---