Heart valve disease– classification, etiology, pathogenesis, and clinical manifestations
Heart valve diseases (valvulopathies ) involve structural or functional abnormalities of one or more heart valves, leading to stenosis (narrowing) and/or regurgitation (insufficiency).
Classification
By type of dysfunction
By valve involved
- Mitral valve disease.
- Aortic valve disease.
- Tricuspid valve disease.
- Pulmonary valve disease (rare, mostly congenital).
Etiology
Acquired causes
- Rheumatic fever: common cause of mitral stenosis.
- Degenerative (senile) calcific changes: aortic stenosis in elderly.
- Infective endocarditis: leads to regurgitation (valve destruction).
- Myxomatous degeneration: mitral valve prolapse.
- Atherosclerosis: contributes to calcific aortic stenosis.
Congenital causes
- Bicuspid aortic valve → predisposed to early stenosis.
- Congenital valve dysplasia.
Pathogenesis
Stenosis
- Progressive fibrosis and/or calcification of valve leaflets → restricted opening.
- Increased pressure gradient across the stenotic valve → upstream chamber hypertrophy (e.g., left atrial hypertrophy in mitral stenosis).
- Decreased downstream flow → reduced cardiac output.
Regurgitation
- Valve incompetence → backward flow of blood during systole (AV valves) or diastole (semilunar valves).
- Volume overload in the upstream chamber → chamber dilation and eccentric hypertrophy.
- Over time → heart failure and atrial arrhythmias (especially in mitral disease).