Introduction: T he subendocardial region is highly vulnerable to hypoperfusion and ischemia. Therefore, given the specific situation of a severe coronary artery disease, a temporary drop in the level of oxygen (i.e. hypotension, anemia, pneumonia) or a temporary need of supplementary oxygen (in atrial tachycardia and hypertension) may cause clinically undetectable suben-docardial lesions. Three cases of mitral valve papillary muscle necrosis were operated on in the CVD clinic, one of them being in cardiorespiratory arrest Methods: Myocardium tissue samples underwent ori-entation and paraffin embedding, with 0.5 u sections being stained with HE, PAS-Alcian, Gomory and Tri-crom Mason, according to staining methods indicated by the producer. Pictures were taken with the ACCU-SCOPE microscope.
Results: In the first case, the papillary muscle remo-ved by surgery indicated a ten-day-old AMI with pe-ripheral centripetal macrophagic digestion. In the se-cond case, the post-mortem macroscopic examination showed a 24-hour-old acute subendocardial infarction of the mitral valve anterior papillary muscle. In the third case, doctors confirmed a seven-to-ten-day-old AMI in the subendocardial region and intramural an-terior papillary muscle. In the fourth case, the anterior papillary muscle showed an acute myocardial infarcti-on of 10- 14 days old.
Conclusions: In the first case, the favorable postope-rative evolution proves that surgical intervention sho-uld start as early as possible after precordial pains. In the second case, legal medicine teaches us that the first manifestation of an AMI could be sudden death. The third case indicates a transitory drop in the myocardial oxygen supply during long operations. The fourth case, the patient showed signs of precipitation and precordi-al pain, but the doctors failed to apply the right treat-ment and she died.