Massive thrombotic occlusion of the large pulmonary arteries.

P ULMONARY heart disease resulting from thrombotic occlusion of the small pulmonary arteries due to repeated emboli has been recognized for some years," 2 and the occurrence of repeated "silent" emboli to the lungs has been reported by Owen and associates.3 Massive thrombosis of the large pulmonary arteries is infrequently considered in the differential diagnosis of obscure cases of right-sided heart failure, although over 200 cases have been described in the literature. The first report apparently was that of H6lie in 1837,4 while Savacool and Charr5 collected 88 cases from the literature and added 12 of their own. Brenner6 found 4 cases in 100 unselected autopsies, and Middleton7 found 53 cases in autopsies over a period of 16 years at the Wisconsin General Hospital. In 5 of the 12 cases of widespread repeated pulmonary emboli reported by Owen and associates,3 the occlusion involved the large branches of the pulmonary artery. The condition has recently been reviewed by Magidson and Jacobson8 who have added 7 more cases. Massive thrombotic occlusion of the main pulmonary arteries has usually been described in association with other diseases, notably pulmonary tuberculosis, carcinoma of the lung, congenital heart disease, and various forms of acquired heart disease. It may, however, occur in the absence of any other disorder, but few cases have been diagnosed in life. The object of this paper is to present a total