DIAGNOSTIC DE L'HEMIBLOC POSTERIEUR GAUCHE A LA PHASE AIGUE DE L'INFARCTUS DU MYOCARDE

Pure left posterior hemiblock (without an associated block of the right branch) in the acute phase of a myocardial infarction appears to occur more frequently than is suggested in the literature. The diagnosis requires the exclusion of factors which obtain during the initial phase of the clinical entity known as a 'myocardial infarction', and which may themselves produce similar modification in the QRS complex, namely: 1. the block associated with an 'electrical lesion' in the posteroinferior position 2. a 'focal' block in a posteroinferior myocardial infarction 3. 'electrical necrosis' of the lateral wall of the left ventricle. Where an attempt has been made to establish diagnostic criteria, electrophysiological studies are necessary in order to verify their accuracy.