Morphological identification of right ventricular failure in cases of fatal pulmonary thromboembolism.

Pulmonary thromboembolism is a life-threatening event potentially determining right ventricular failure. Even if the pathophysiology of this phenomenon has been widely investigated, no morphological demonstration of right ventricular ischemic damage determining right ventricular failure in cases of fatal pulmonary embolism has been reported till now. We performed an immunohistochemical investigation with the markers fibronectin and C5b-9 in 26 cases of fatal pulmonary thromboembolism (16 ♀, 10 ♂, mean age 56.4 years), as well as in 25 cases of myocardial infarction (16♀, 9♂, mean age 60.8 years) and 20 cases of hanging (3♀, 17♂, mean age 40.8 years). In each case, at least one tissue slide from both cardiac ventricles (free wall of the right ventricle, anterior and/or posterior wall of the left ventricle) was prepared. The reactions were semiquantitatively classified and the groups compared. In the study group, the occurrence of ischemic changes at the right ventricle was significantly higher than in cases of myocardial infarction and global hypoxia due to hanging. The determining aspect of the immunohistochemical examination is the identification of the prevalent ischemic lesion at the right ventricle compared to the left one. This may indicate the primary involvement of the right ventricle thus demonstrating a right ventricular failure.