[Morphological changes in the lungs in myocardial infarct].

Morphologica lesions in the lungs were studied in 48 rabbits with experimental myocardial infarction and in 17 fatal cases where death occurred at various intervals after the onset of myocardial infarction. The study revealed 4 interrelated stages of morphological lesions in the lungs due to the development of myocardial infarction: (1) hypoatelectasis, (2) classical atelectasis, (3) the stage of alveolitis, (4) the stage of bronchopneumonia. A certain regularity was established in the dynamics of the oxidative-reductive enzymes in alveolar cells: early in the disease the activity of succinate-, malate- and lactatedehydrogenase decreased but by the end of the 1st week began to recover. In cases where atelectasis was complicated by bronchopneumonia the activity of succinatedehydrogenase again decreased.