title: Right bundle-branch block unmasking a myocardial infarction.
abstract: A patient with an acute anteroseptal myocardial infarction and intermittent right bundle-branch block is presented. Abnormal Q waves in right precordial leads were only observed during right bundle-branch block. In the absence of right bundle-branch block, depolarization of the right ventricular free wall concealed the abnormal Q waves typical of an anteroseptal infarct. Right bundle-branch block, by preventing early activation of the right ventricular free wall, facilitated the correct diagnosis and localization of the infarction.
authors.affiliation: Department of Internal Medicine, University of Florida College of Medicine, Gainesville 32610-0277, USA.
authors.forename: Mario D
authors.initials: MD
authors.lastname: Gonzalez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002037:Bundle-Branch Block / Q000150:complications* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology