Diseases of the valves of the heart. Rheumatic disease. Cardiomiopathy

♦ Usually due to hematogenously transmitted infections by bacteria:

– Most commonly Streptococcus (viridans, bovis,fecalis), which is less virulent than Staphylococcus aureus

♦ Approximately 30% occur on normal valves

♦ Usually there is some predisposition, such as:

– Cardiac abnormality which creates turbulence, and presumably endothelial injury, such as valve stenosis/regurgitation, prosthesis, septal defects)

– Clinical circumstance, such as immune suppression, cancers

– IV drug use may lead to infectious endocarditis, usually of right sided valves

♦ Complications of infectious endocarditis include valve insufficiency (or stenosis less commonly), septic systemic embolization

♦ Grossly, friable vegetaions on side of direct flow, often near free edge, composed of thrombus material and bacteria (or fungi, etc.)

♦ Non-bacterial thombotic endocarditis (marantic en_x0002_docarditis):

– Occurs in setting of cancer (especially mucinous adenocarcinoma) or other systemic wasting illness

– May embolize

– Grossly, small or large fibrin masses, without organisms, present at lines of closure on the aortic or mitral valves

– Microscopically, fibrin and entrapped red blood cells, no inflammation

♦ Libman-Sacks disease (verrucous endocarditis):

– Seen in systemic lupus erythematosus (SLE)

– Multiple small leaflet vegetations, usually on non_x0002_flow side (ventricular surface) of mitral and/or tricuspid valves

– Microscopically, fibrin intermixed with cellular debris and scattered inflammatory cells

Micropreparation

Rheumatic acute warty endocarditis.
Hematoxylin and eosin staining:
a - thrombotic overlays (warts) on the surface of the mitral valve,
devoid of endothelial cover;
b - lymphohistiocytic infiltrates in the valve leaflet;
c - full-blooded vessels
Focus of necrosis, valve leaflets
without sting and imposition
fresh blood clots, without
signs of an organization with
limited number of colonies Microorganisms.
• At the base of the clots of the valves
Clapon Gusto; infiltrated neutrophilic leukocytes.
• myocardial vessels, microbial emboli
• Around the embolus infiltrated
leukocytes.