Fascicular conduction blocks and their relationship to complete heart block in Nigerians

Following electrocardiographic analysis, isolated or combined blocks in the intraventricular trifascicular system including predivisional left bundle branch block with left posterior hemiblock in Nigerians are presented and the underlying causes reviewed. The rarity of complete heart block, despite the not uncommon fascicular blocks, is of interest and may be related to the population age structure considering the invariably slow rate of degeneration of conduction fibres in the system.