absence of streptococci from the lesions support the concept that R.F result
from immune response against the bacteria.

Acute rheumatic carditis is characterized by inflammatory changes only in single outer layer of heart

endocardium involvement isnot commonin Rheumatic fever and if occur mitral and aortic
valves are common.

Chronic rheumatic heart disease is characterized by reversible deformity of one or more cardiac valves,

Valvular stenosis and regurgitation lead to heart failur and infective endocaridtis.

Stenosis is more than regurgitation and is most common cause of mitral stenosis.

In Chronic rheumatic mitral valvulitis the right atrium is dilated and hypertrophied, mural thrombi may be present which's source of
systemic emboli

In mitral regurgitation, the deformed mitral leaflets are retracted and the added
volume load on the left ventricle causes left ventricular atrophy

Infective endocarditis is infection of cardiac myocytes resulting in the formation of an adherent mass of thrombotic debris and organism

Subacute endocarditis:associated with infection of the valves by high virulent
microorganism as staphylococcus aureus

Acute endocarditis cause rapidly
progressive infection with few local host reaction

Subacute endocarditis:- infection of normal valves accompanied by the development of a local inflammatory reaction and granulation tissue in the affected valve.

The most common abnormalities of valve predispose to infective endocarditis
are prosthetic valve, chronic rheumatic heart disease, DACS and mitral valve
prolapse

Infective endocarditis is a particularly easy to eradicate

the inflammatory response to the
infection is relatively scant, so that even a virulent organism can proliferate in
uncontrolled fashion

The hall mark of infective endocarditis is the presence of Aschoff bodies

All are true regard to morphology of infective endocarditis EXCEPT

Systemic emboli may occur due to friable nature of the vegetation sites, and •
abscesses usually develop at the sites of such infarcts because of embolic
fragments contain large number of virulent organism

Non bacterial thrombotic endocarditis is valvular lesions that are sterile and do
not contain microorganism.

Endothelial abnormalities and hyper-coagulable states predispose to development,of Non bacterial thrombotic endocarditis