VALVULAR HEART DISEASE
Mitral StenosisEtiology of Mitral Stenosis
Rheumatic heart disease: 77-99% of all cases Congenital: rareMS- Pathophysiology
Progressive fibrosis ,thicking ,calcifications of of valve leaflets and fusion of commisures leads to gradual narrowing of mitral valve orifice,symptoms begin at areas less than 2 cm2. Restricted blood flow from LA to LV and LA pressure rises -Leads to left atrial enlargement and atrial fibrillation(very common) Pulmonary congestion(reduced lung compliance) pulmonary venous hypertension –Progressive and gradual rise in pulm.venous HTN leads to increase pulm.vascular resistance and pulm.arterial HTN leading to RVH-later RV dilatation and RT heart Failure .SYMPTOMS
AsymptomaticBreathlessness (pulmonary congestion) dominant •Fatigue (low cardiac output) • Palpitation (atrial fibrillation) • Haemoptysis (pulmonary congestion, pulmonary embolism) •Cough (pulmonary congestion) • Chest pain (pulmonary hypertension) • Oedema, ascites (right heart failure)Thromboembolic complications(e.g. stroke,ischaemic limb)SIGNS
GENERAL Dyspneaic,Mitral facies -malar flush(pinkish-purple patches on the cheeks)Pluse usually irregular due to Atrial fibrillation LOCAL:Palpation : Apex tapping(loud S1)• Auscultation: Loud first heart sound,Mid-diastolic rummbling murmur •Investigations
ECG: Right ventricular hypertrophy CXR: LA enlargement and pulmonary congestion. ECHO Doppler: The GOLD STANDARD for diagnosis.. Cardiac catheterization: Coronary artery disease Pulmonary artery pressure,Management of MS cont… Medical management This consists of1. anticoagulation to reduce the risk of systemic embolism, 2. In atrial fibrillation ventricular rate control with digoxin, β-blockers3. diuretic to control pulmonary congestion. 4. Antibiotic prophylaxis against infective endocarditis is no longer routinely recommended.Mitral balloon valvuloplasty and valve replacement sever symptomatic mitral stenosis
Mitral Regurgitation
Causes of mitral regurgitationRheumatic disease is the principal cause in countries where rheumatic fever is common but elsewhere, including in the UK, other causes are more important.Mitral valve prolapse • Dilatation of the left ventricle and mitral valve ring (e.g. coronary artery disease, cardiomyopathy) • Ischaemia or infarction of the papillary muscle
Mitral valve prolapse
Displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. Occurs in 3-5% of adults Caused by congenital anomalies or degenerative myxomatous changes. Asymptomatic, palpitations, atypical chest pain, dyspnea on exertion, low body mass index, and electrocardiogram abnormalities ,small risk of embolic stroke. Mid systolic click and late systolic murmur Often require no treatment. Prognosis is goodPathophysiology of MR
Pure Volume Overload When blood abnormally flows backward from the left ventricle to the left atrim, both chamber's volume increases. Due to the increased volume, left atrial pressure also increases which leads to compensatory left atrial enlargement and can predispose to atrial arrhythmias and later to pulmonary hypertension . The left ventricular volume also increases . As mitral regurgitation worsens, left ventricular hypertrophy develops in order to maintain normal left ventricular pressures. Eventually the left ventricle reaches maximum hypertrophy, left ventricular pressures increase, and systolic heart failure ensues.SYMPTOMS
- Chronic mitral regurgitation produces a symptom complex that is similar to that of mitral stenosis . -Dyspnoea (pulmonary venous congestion) -Fatigue (low cardiac output) -Palpitation (atrial fibrillation, increased stroke volume) -Oedema, ascites (right heart failure) -Complications Infective endocarditis,Thromboemb- olic complications.Signs
Pulse : Regular or irregular (Atrial fibrillation) LOCAL Apex displaced hyperdynamic (Thrusting) Apical pan.systolic murmur ,Soft S1Investigations in MR
ECG: May show LA enlargement, atrial fibrillation and LV hypertrophy . CXR: LA enlargement, central pulmonary artery enlargement,pulm congestion and pulm edema. ECHO -Doppler: Estimation of LA, LV size and functions. Cardiac catheterization. Diagnosis and for Coexisting coronary artery diseaseManagement of MR
Moderate MR can be treated medicallywith diuretics and vasodilators. Digoxin and anticoagulants should be given if AF is present . Worsening symptoms, progressive cardiomegaly or echocardiographic evidence of deteriorating left ventricular function are indications for mitral valve replacement or repair..Aortic Stenosis
Aortic StenosisNormal Aortic Valve Area: 3-4 cm2
Etiology of Aortic Stenosis
Congenital-birth or becomes apparent during infancy Bicuspid-take years to develop as the valvebecomes fibrotic and calcified, and these patients present as young to middle-aged adults. Rheumatic. similar age but is usually accompanied by mitral valve disease Degenerative/Calcific. In older people, structurally normalaortic valves may become stenotic as the result of fibrosis and calcification. Patients under 70: >50% have a congenital cause Patients over 70: 50% due to degenerativePathophysiology of Aortic Stenosis
Pressor Overload Cardiac output is initially maintained in patients with aortic stenosis at the cost of a steadily increasing pressure gradient across the aortic valve. With progression of the stenosis the LV becomes increasingly hypertrophied .Eventually, the LV can no longer overcome the outflow tract obstruction and LV failure results, leading to pulmonary oedemaPresentation of Aortic Stenosis
Asymptomatic (mild/moderate) The classic triad of symptoms (sever): Syncope: exertional Angina:Angina arises either because of the increased demands of the hypertrophied, or the presence of coexisting CAD, which affects over 50% of patients. Dyspnea: on exertion due to heart failure (systolic and diastolic). Complications' :Sudden cardiac death,Heart failure,Conduction defects,Calcific embolization.