1

Aortic Stenosis

“Senile” calcific aortic stenosis.

Degeneration and calcification of bicuspid aortic valve.

Chronic Rheumatic Heart Disease

Aortic valve structure

Endocardium

Ventricular side

Elastic fibers in black

Fibrosa

Spongiosa

Calcification

2

Aortic insufficiency due to aortic dissection

• Hypertension• Connective tissue disorders

Marfan’s: 1 in 5000.70-85% familial (Autosomal dominant)Fibrillin-1 (15q21) ~ 500 distinct

mutations

Medial degeneration without atherosclerosis

Mitral Stenosis

• Chronic Rheumatic Heart Disease

• (Rare) Mitral annular calcificationMyxoma

Acute Rheumatic FeverImmunologically mediated, following 1-6

weeks after pharyngitis with Group A Streptococcus in 3% of those infected.

?Antibodies ? Hypersensitivity reaction induced by streptococcal M proteins with cross-reaction with similar antigenic determinants in joints, heart, skin, CNS.

Clinical Diagnosis: revised Jones criteria

Acute Rheumatic Fever

PancarditisPericarditisMyocarditis (Aschoff body)Endocarditis with sterile vegetations

Death in acute rheumatic fever is very rare (<1%) and due to cardiac involvement

3

Aschoff body of acute rheumatic carditis: a cardiac granuloma

Acute rheumatic fever: involvement of mitral chordae tendineae

Native chordae bound together by fibrous tissue in chronic rheumatic mitral valve disease

Chronic Rheumatic Heart Disease

Follows Acute Rheumatic Heart Disease by decades.MV involved in 65-70%MV & AV in 25%

Mitral stenosis, aortic stenosis.Arrhythmias (A. fib. with left atrial enlargement).Heart failure.Predisposed to infective endocarditis.

4

Chronic Rheumatic Heart Disease: “Fishmouth”deformity of the mitral valve

Mitral Valve Prolapse• 2 populations: women in 20s; men in 40-50s; the

gross and microscopic appearances of the valves are the same.

• Most are asymptomatic• Mid-systolic click• Rarely: chest pain, dyspnea, fatigue, or psychiatric

manifestations• ~3% have complications:

Infective endocarditisMitral insufficiencyThrombus formation with embolizationArrhythmia/sudden death (unknown mechanism)

Normal (aortic) valve structure

Myxomatous, prolapsing mitral valve

“Myxomatous” mitral valve

5

Acute endocarditis of mitral valve

Rupture of MV papillary muscle with inferior wall MI

The following 6 slides on valve prostheses were not presented in

the lecture on 1-4-06

Heart Valve Prostheses: Complications

• Mechanical: component failure• Bioprostheses: degeneration with

calcification• Both: Paravalvular leak, endocarditis.

Thrombosis and tissue overgrowth are less common in bioprostheses than in mechanical valves.

Bioprosthetic (Hancock)valve: Degeneration and tissue overgrowth

6

Thrombus occluding AV prosthesis

Thrombus covering mitral valve prosthesis (viewed from opened left atrium

Endocarditis (arrows on vegetations) of ball valve prosthesis (Starr-Edwards)