Abstract: Massive pulmonary embolism is a embolic embolism and thrombosis in the pulmonary trunk and the left or right pulmonary arterier. In the 5 cases of massive pulmonary embolism, 4 of them were pulmonary thrombosis associated with chronic pulmonary heart disease and the pulmonary hypertension and andere case of pulmonary embolism occurred in a patient with kidney carcinoma. Sudden death appeared in 5 cases. None of the patients were correctly diagnosed before death as to the massive pulmonary embolism. In the this paper the incidence, pathogenesis, pathologic changes and clinical manifestation of massive pulmonary embolism were discussed.

Key words: pulmonary trunk, pulmonary artery, massive pulmonary embolism