Pathology: Normal mitral valve area (MVA): 4-6 cmAcute rheumatic feverImmune-mediated inflammation of valves- the leaflets thickened- the commissures fused- thickening and shortening of chordae tendineae: Narrowing of mitral valve orifice
Pathology • Normal mitral valve area (MVA): 4-6 cm2 • Acute rheumatic fever • Immune-mediated inflammation of valves – the leaflets thickened – the commissures fused – thickening and shortening of chordae tendineae • Narrowing of mitral valve orifice
Pathophysiology: MVA 2 cm?: increased left atrialpressure(LAP) is necessaryfor normaltransmitralflow MVA 1cm?: LAP 25 mm Hg required→PVP and PCWP↑→>exertional dyspnea: ChronicelevationofLAP-→>pulmonaryandtricuspidpulmonaryhypertension,regurgitation → right heart failure
Pathophysiology • MVA 2 cm2 : increased left atrial pressure (LAP) is necessary for normal transmitral flow • MVA 1cm2 : LAP 25 mm Hg required→ PVP and PCWP→exertional dyspnea • Chronic elevation of LAP→pulmonary hypertension, tricuspid and pulmonary regurgitation → right heart failure
: Progressive dilation of the LA predisposes:- Mural thrombi: embolize in 20% of patientsPatients at high risk.over35years old: Atrial fibrillation with a low cardiac outpu: large LA appendage- Atrial fibrillation:in up to 40% of patients decreases cardiac output by 20%
• Progressive dilation of the LA predisposes: – Mural thrombi: embolize in 20% of patients Patients at high risk: • over 35 years old • Atrial fibrillation with a low cardiac output • large LA appendage. – Atrial fibrillation: • in up to 40% of patients • decreases cardiac output by 20%
Clinical Manifestations. Histories of rheumatic fever, murmur·Dyspnea: Palpitations· Chest pain: Hemoptysis: a late finding·Edema: Thromboembolism: may be 1st symptom
Clinical Manifestations • Histories of rheumatic fever, murmur • Dyspnea • Palpitations • Chest pain • Hemoptysis: a late finding • Edema • Thromboembolism: may be 1st symptom
Physical Exam? Low-pitched diastolicrumbleOpening snapS, T, Atrial fibrillation, P,Coexistent murmurs. RV heave: Elevated neck veins, hepatomegaly, ascitespedal edemaThromboembolic events
Physical Exam • Low-pitched diastolic rumble • Opening snap • S1, Atrial fibrillation, P2 • Coexistent murmurs • RV heave • Elevated neck veins, hepatomegaly, ascites, pedal edema • Thromboembolic events