Aortic Stenosis
“Senile” calcific aortic stenosis.
Degeneration and calcification of bicuspid aortic valve.
Chronic Rheumatic Heart Disease
Endocardium
Fibrosa
Spongiosa Elastic fibers in black
Aortic valve structure Ventricular side
1 Calcification
2 3 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
4 Medial degeneration without atherosclerosis
Mitral Stenosis
• Chronic Rheumatic Heart Disease
• (Rare) Mitral annular calcification Myxoma
5 Acute Rheumatic Fever Immunologically 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
Pancarditis Pericarditis Myocarditis (Aschoff body) Endocarditis with sterile vegetations
Death in acute rheumatic fever is very rare (<1%) and due to cardiac involvement
6 Aschoff body of acute rheumatic carditis: a cardiac granuloma
Acute rheumatic fever: involvement of mitral chordae tendineae
7 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.
8 9 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 endocarditis Mitral insufficiency Thrombus formation with embolization Arrhythmia/sudden death (unknown mechanism)
10 Normal (aortic) valve structure
Myxomatous, prolapsing mitral valve
11 “Myxomatous” mitral valve
12 Acute endocarditis of mitral valve
13 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
14 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
15 Thrombus occluding AV prosthesis
16 Thrombus covering mitral valve prosthesis (viewed from opened left atrium
Endocarditis (arrows on vegetations) of ball valve prosthesis (Starr-Edwards)
17