On the electrocardiographic diagnosis of biventricular infarctions

To diagnose posterior and anterior biventricular infarctions it is necessar y to record from right and left thoracic and high abdominal unipolar leads. These supplementary leads are dependable, can be repeated as many times as needed and show the evolution from signs of myocardial injury to those of dead tissue (Q waves of 0.04 sec or more). This electrocardiographic evolut ion increases the diagnostic value of the electrical exploration, since the injury current can be observed also in other conditions. The diagnosis of right ventricular infarction can be established even in the presence of RBB B. Signs of a dead zone in the free right ventricular wall are more frequen tly observed in posterior biventricular infarctions than in anterior ones. In these cases, the signs of subepicardial injury are more accentuated in t he right thoracic unipolar leads than in V-3, indicating anterior sight ven tricular involvement. These signs are also observed in experimental studies made in animals. This electrocardiographic exploration opens a wide field for the diagnosis of myocardial infarction, particularly in biventricular i nvolvement, including old myocardial scars, and in discarding signs of peri carditis manifested only by the upward displacement of the ST segment. A re view of the medical literature concerning diagnosis of biventricular infarc tions is presented.