title: [Hemiblocks: electrocardiographic diagnosis].
abstract: Left hemiblocks or fascicular blocks are conduction defects which lead to asynchronous left ventricular activation. The classical diagnostic criteria must be respected, especially the degree of left axial deviation in complete forms. Other, less well-known criteria, which include the widening of the QRS complex opposite the myocardial walls showing delayed activation, seem very useful for making the diagnosis. The real diagnostic difficulties lie in incomplete forms because the inferior limits of axial deviation in this type of conduction defect are not known and clinical progression is usually the decisive factor. Precise understanding of the clinical signs of hemiblock is useful in clinical practice for the discussion of the significance of Q waves in the right precordial leads or for explaining sudden changes in QRS axis or amplitude.
authors.affiliation: Service de cardiologie B, CHU Bichat, Claude-Bernard, Paris.
authors.forename: P E
authors.initials: PE
authors.lastname: Valère
mesh_terms: D002037:Bundle-Branch Block / Q000145:classification / Q000175:diagnosis*; D004562:Electrocardiography; D006801:Humans
vernacular_title: Les hémiblocs; diagnostic électrocardiographique.