[Discriminative analysis in detecting cardiac insufficiency in myocardial infarct on the basis of the values of stroke volume and blood lactic acid level].

In 203 patients with large focal and transmural myocardial infarctions the cardiac output was studied by means of the dye dilution method, as well as the content of the lactic (Barker and Summerson's technique) and pyruvic acids (Travina's technique). Along with the growth of cardiac insufficiency a fall was observed in the cardiac and stroke indices, and a growing content of the lactic and pyruvic acids and of the L/P factor. The stroke index and the blood lactate level proved to be the most informative values. With a stroke index below 24 ml/m2 all patients with myocardial infarction displayed signs of cardiac insufficiency, while with a stroke index above 54.2 ml/m2 cardiac insufficiency was lacking. A stroke index falling between 24 and 54.2 ml/m2 was observed in both the patients with cardiac insufficiency, and in those without it. A lactic acid content above 31.8 mg% was always concomitant with cardiac insufficiency. With the lactic acid level ranging from 16 to 31.8 mg% the probability of cardiac insufficiency was doubtful.