Clinical implications of atrioventricular and intraventricular conduction abnormalities II. Acute myocardial infarction.

The diagnostic criteria and the clinical implications of atrioventricular and intraventricular conduction defects have been reviewed. Information derived from His bundle electrocardiographic studies has been incorporated in the discussion and the importance of the site of block has been stressed. Defects in the trifascicular intraventricular conduction system and their relation to prognosis and to development of complete heart block are outlined. Data on the prognosis of conduction abnormalities during acute myocardial infarction are reviewed in depth and current indications for temporary and permanent pacemaker implantation are presented.