Cotton emboli (cellulose II polymorph, "rayon") of the coronary arteries

Foreign-body granulomas within intramyocardial arteries in a transcoronary safety assessment in pigs

Foreign-body granulomas within intramyocardial arteries were detected in three domestic pigs (Sus scrofa domestica) in a routine transcoronary safety assessment study. The foreign bodies stained light grayish-blue by hematoxylin and eosin (H&E) and were strongly birefringent by polarized light microscopy. By their morphological features, they were identified as cotton fibers. Embolization of foreign-body material into the myocardial arteries following catheter-based procedures is an unusual event, and its occurrence may lead to granulomatous foreign-body reaction and misinterpretation of histological results.

Granulomatous inflammation of the heart

Morphologic characteristics of granulomatous inflammation in the heart and pericardium are discussed. In rheumatic fever, two types of myocardial lesion are present--a nonspecific myocarditis and a specific lesion characterized by granulomas known as Aschoff's nodules. The latter undergo a cycle of development and resolution; in their mature stage, they contain Aschoff's cells which are uni- or multinucleated histiocytes with a serrated nuclear chromatin bar. Ultrastructural studies do not suggest a relationship between these cells and cardiac or smooth muscle cells. In metabolic disorders, granulomas occur in Farber's disease (lipogranulomatosis), gout (in which tophi are associated with calcific deposits and with a foreign body cellular reaction), the various syndromes of oxalosis (in which oxalate deposits also lead to a foreign body reaction), and in chronic granulomatous disease of childhood. Foreign body giant-cells can also be found in association with calcification of necrotic myocytes and in the syndromes of "cholesterol pericarditis." Well-developed granulomas occur in sarcoidosis, giant cell myocarditis, as a reaction to foreign bodies and devices implanted within the cardiovascular system, and in certain diseased caused by infective agents (tuberculosis, fungal and parasitic disorders). Infiltration of the heart by nongranulomatous masses of histiocytes can occur in Whipple's disease, Niemann-Pick disease, the hyperlipoproteinemias, Gaucher's disease, and in proliferative disorders of the mononuclear phagocyte system (juvenile xanthogranuloma, Chester-Erdheim syndrome, and malignant histiocytosis).

Calcific deposits developing in a bovine pericardial bioprosthetic valve 3 days after implantation

Calcific deposits, localized in a thin layer of thrombus covering the cuspal surfaces, were present 3 days after implantation in a valved pulmonic conduit that contained an Ionescu-Shiley bovine pericardial valve and was placed in a 29-year-old man with double outlet right ventricle, valvular and infundibular pulmonic stenosis, and ventricular septal defect. Factors that may have contributed to such a rapid calcification were the relatively young age of the patient, the development of acute renal insufficiency postoperatively, and the administration of large amounts of calcium chloride intravenously during blood transfusions and during episodes of cardiac arrest.