高血压英文ppt精品课件valvularheart

Valvular Heart Disease,Dr. Randa Al-Harizy Prof. of Internal Medicine,Tricuspid Valve,MITRAL STENOSIS Almost all mitral stenosis is due to rheumatic heart disease. It is much more common in women. Other causes include: Lutembacher's syndrome, which is the combination of acquired mitral stenosis and an atrial septal defect, carcinoid tumours and SLE.,Valvular Heart Disease,PATHOPHYSIOLOGY When the normal valve orifice area is reduced to 1 cm2, severe mitral stenosis is present. To maintain cardiac output, the left atrial pressure increases and left atrial hypertrophy and dilatation occur. Consequently, pulmonary venous, pulmonary arterial and right heart pressures also increase, followed by pulmonary oedema. Pulmonary hypertension leads to right ventricular hypertrophy, dilatation and failure resulting in tricuspid regurgitation.,Valvular Heart Disease,COMPLICATIONS OF MITRAL STENOSIS Atrial fibrillation Systemic embolization Pulmonary hypertension Pulmonary infarction Chest infections Infective endocarditis (rare) Tricuspid regurgitation Right ventricular failure,Valvular Heart Disease,SYMPTOMS Usually there are no symptoms until the valve orifice is moderately stenosed (i.e. has an area of 2 cm2). Because of pulmonary venous hypertension and recurrent bronchitis, progressively severe dyspnoea develops. A cough productive of blood-tinged, frothy sputum and occasionally frank haemoptysis may occur. Right heart failure and its symptoms of weakness, fatigue and abdominal or lower limb oedema. Atrial fibrillation, giving rise to palpitations. Atrial fibrillation may result in systemic emboli.,Valvular Heart Disease,SIGNS Face: mitral facies or malar flush. Pulse: a small-volume pulse, may be an irregularly irregular pulse. Jugular veins: Distension of jugular veins in right heart failure.Palpation: There is a tapping impulse felt parasternally on the left side (palpable first heart sound). A sustained parasternal impulse due to right ventricular hypertrophy may also be felt. Auscultation: loud first heart sound, and 'opening snap'. This is followed by a low-pitched 'rumbling' mid-diastolic murmur at the apex with presystolic accentuation.,Valvular Heart Disease,INVESTIGATIONS Chest X-ray: small heart with an enlarged left atrium, Pulmonary venous hypertension, a calcified mitral valve, signs of pulmonary oedema or pulmonary hypertension. ECG: shows a bifid P wave or AF, features of right ventricular hypertrophy (right axis deviation and perhaps tall R waves in V1) Echocardiogram: assessment of the mitral valve apparatus and calculation of mitral valve area, also determines left atrial and right ventricular size and function. Estimate of pulmonary artery pressure Cardiac catheterization,Valvular Heart Disease,TREATMENT Mild mitral stenosis may need no treatment other than prompt therapy of attacks of bronchitis. Antibiotic prophylaxis for infective endocarditis. Mild dyspnoea is treated with low doses of diuretics. Atrial fibrillation requires treatment with digoxin and anticoagulation to prevent atrial thrombus and systemic embolization. If pulmonary hypertension develops, surgical relief of the mitral stenosis is advised. Surgical treatment includes; Trans-septal balloon valvotomy, Closed valvotomy, Open valvotomy or Mitral valve replacement.,Valvular Heart Disease,CAUSES The most common cause is rheumatic heart disease (50%) and a prolapsing mitral valve. Other causes include; aortic valve disease, acute rheumatic fever, myocarditis, dilated cardiomyopathy, hypertensive heart disease, ischaemic heart disease, infective endocarditis, hypertrophic cardiomyopathy, SLE, Marfan's syndrome, Ehlers-Danlos syndrome, rupture of the chordae tendineae (e.g.due to myocardial infarction).,MITRAL REGURGITATION,PATHOPHYSIOLOGY Regurgitation into the left atrium produces left atrial dilatation but little increase in left atrial pressure. With acute mitral regurgitation the left atrial v wave is greatly increased and pulmonary venous pressure rises to produce pulmonary oedema. Since a proportion of the stroke volume is regurgitated, the stroke volume increases to maintain the forward cardiac output and the left ventricle therefore enlarges.,MITRAL REGURGITATION,SYMPTOMS Mitral regurgitation can be present for many years before any symptoms occur. The increased stroke volume is sensed as a 'palpitation'. Dyspnoea and orthopnoea develop owing to left ventricular failure. Fatigue and lethargy develop because of the reduced cardiac output. In the late stages of the disease the symptoms of right heart failure also occur and eventually lead to congestive cardiac failure. Cardiac cachexia may develop. Thromboembolism is less common than in mitral stenosis, but subacute infective endocarditis is much more common.,MITRAL REGURGITATION,SIGNS Laterally displaced (forceful) diffuse apex beat and a systolic thrill (if severe). Soft first heart sound. Pansystolic murmur, radiating widely over the precordium and into the axilla. Prominent third heart sound. The signs related to atrial fibrillation, pulmonary hypertension, and left and right heart failure develop later in the disease.,