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by auy body detaclied and transported from the interior of the heart, 

 or of some vessel. Thrombi occur as the result of an injury to the 

 wall of the vessel, or may follow its compression or dilatation ; they 

 may result from some alteration of the wall of the vessel by disease, or 

 by the retardation of the circulation. These formations may occur 

 during life, in the heart, arteries, veins, or in the portal sj'stem. 

 When a portion of fibrin coagulates in one of the arteries and is car- 

 ried along by the circulation, it will be arrested, of course, in the 

 capillaries, if not before; when in the veins it may not be stopped 

 until it reaches the lungs; and when in the portal sj-stcm the capilla- 

 ries of the liver will prevent its further progress. The formation of 

 tlirombi may act primarily by causing partial or complete obstruction, 

 and secondarily, either by larger or smaller fragments becoming- 

 detached from their end, and by being carried along by the circula- 

 tion of the blood to remote vessels, embolism; or b}' the coagulum 

 becoming softened and converted into pus, constituting suppurative 

 phlebitis. These substances occur most frequently in those affections 

 characterized by great exhaustion or debility, as j)neumonia, purpura 

 hemorrhagica, endocarditis, phlebitis, puerperal fever, hemorrhages, 

 etc. These concretions may form suddenly and produce instantane- 

 ous death byretai'^ing the blood current, or they may arise gradually, 

 in which case the thrombi maybe organized and attaclied to the walls 

 of the heart, or they may §often, and fragments of them (emboli) may 

 be carried awaj'. The small, wart-like excrescences, occurring some- 

 times in endocarditis, may occasionally form a foundation on which a 

 thrombi may develop. 



Sipnptoms. — When heart clot or thrombus exists in the right side 

 the return of blood from the body and the aeration in the lungs are 

 impeded, and if death occurs it is owing to sjTicoiJe rather than to 

 strangulation in pulmonary respiration. There will be hurried and 

 gasping breathing, ijaleness and coldness of the surface of the bod}^ 

 a feeble and intermittent or fluttering pulse, and fainting. When a 

 fibrinous coagulum is carried into the j)ulmonary arterj' from the right 

 side of the heart, the indications are a swelling and infiltration of the 

 lungs and pulmonary apoplexy. When the clot is situated in the left 

 canities of the heart or in the aorta, death, if it occurs, takes place 

 either suddenly or at the end of a few hours from coma. 



Pathology. — When a coagulum is observed in the heart it may 

 become a question whether it was formed during life or after death. 

 The loose, dark coagula, so often found after death, are polypi. If 

 the dej)osition has taken i)lacc during the last moments of life, the 

 fibrin viill be isolated and soft, but not adherent to the walls; if it be 

 isohited, dense, and adherent or closely intertwined with the muscles 

 of the paiDillse and tendinous cords, the deposition has occurred more 

 or less remote from the act of dying. Occasionally the fibrin may be 

 seen lining one of the cavities of tlio heart, like a false endocardium, 



