Fluoroscopic differentiation between leaflet escape (LE) and valve thrombosis (VT) of the Edwards-Duromedics mitral valve.

Although differential diagnosis between LE and VT of an Edwards-Duromedics mitral valve can be suspected on clinical, phonocardiographic and echocardiographic bases, we propose that fluoroscopy is the rapid, non-invasive test to distinguish between both conditions if properly conducted and interpreted: with adequate orientation of the X-ray beam, the presence of both leaflets and their range of motion can be reliably assessed.

Normally and abnormally functioning left-sided porcine bioprosthetic valves after long-term implantation in patients: distinct spectra of histologic and histochemical changes.

This morphologic study (X-ray examination of gross specimens, histologic study and histochemical staining) compares two groups of explanted left-sided bioprosthetic valves: group I, 6 valves with normal cusp function and group II, 10 valves with significant dysfunction. Implantation periods ranged from 26 to 79 months. A computerized descriptive statistical method (principal component analysis) is used to analyze the qualitative results. Although qualitatively identical alterations are observed in both groups, the findings in the deep layers of the cusps of severe collagen breakdown, intensive fibrin penetration and various degrees of calcification are restricted to group II. Other findings of interest in both groups include amyloid deposits (four cases) and layering of fusiform host cells on the cusp surface (three cases). The computerized study shows that individuals of one clinical group are morphologically different from those of the other. Mechanical stress may contribute to surface alterations early after implantation, while further collagen breakdown and macrophagic activity result in deep penetration of plasma components and fibrin. Subsequent calcification is likely to be dystrophic rather than metabolic. Colonization of the cuspal surface by endothelial cells after long-term implantation of bioprosthetic valves expresses a new type of relation between host and bioprosthesis.

Histopathology of the aortic valve in patients with a previous history of acute rheumatic fever. An analysis of 63 surgical specimens.

In a series of 63 surgical patients with a positive history of rheumatic fever and whose aortic valve was removed either singly or in combination with other valves, the histological examination of the aortic valves showed functional lesions in 22 cases (35%). Organic lesions of inflammatory origin, destruction of the architecture with scarring and presence of hypertrophic vessels, were observed in 19 valves (30%). The other cases were doubtful. This ratio was identical in uni- and plurivalvular involvement. Anatomic aspects and significance of microscopic lesions of the aortic valves were discussed. The role of microthrombi and turbulent flow in the pathogenesis of the functional lesions is stressed. The authors conclude that there is no correlation between the anatomic aspects of the aortic valve deformity and the presence of histologically proven organic lesions of inflammatory origin. This provides support to the current opinion that rheumatic carditis is mainly a disease of the mitral valve.