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Definition and Classification of Valvular Heart Disease

Valvular heart diseases can affect any of the valves in the heart. Diseases valves may have an
altered structure, which changes the blood flow. Valvular heart disease is usually described by the duration of the dysfunction (acute vs. chronic), the valves involved, and the nature of the valvular dysfunction (stenosis, insufficiency, or a combination of stenosis and insufficiency).

The function of the heart is to circulate blood in closed circuit to the lungs, where blood is oxygenated, and out to the body, where oxygen provides fuel for cellular metabolism. So, if any problem with cardiac valvular can effect in amount of cardiac output because its affecting the valvular of heart result in either obstruction to forward flow (stenosis) or reversal of flow across an incompetent valve (regurgitation).

The diagnosis of valvular heart disease is based on patient history, physical assessment, and diagnostic testing. Valvular heart desease are classified by 5 names. Those are mitral stenosis, mitral regurgitation, mitral valve prolapsed, aortic stenosis and aortic regurgitation.


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A. Mitral Valvular Stenosis

Mitral stenosis is narrowing of the mitral valvular. Most patients with valvular mitral stenosis asymptomatic for several years and may not have symptoms until the fourth or fifth decades of life.

The left atrium meets resistance as it attempts to pass valvular mitral and ejecting blood forward into left ventricle. Eventually the left atrium dilates and contractility decreases. Forward flow is decreased and fluid backs up into lungs. Increased volume in the lungs increases pressure in lungs developing congestive heart failure if not treated properly.




Causes of Valvular Mitral Stenosis :

1. The rheumatic heart disease is main trigger the mitral valve to become inflamed tissue then fibrinous occur, resulting in leaflet thickening and narrowing of the mitral valve.

2. Congenital abnormality causes the valve to thicken by fibrosis and calcification, obstructing blood flow.

3. Myxoma (noncancerous tumor in left atrium) obstructs the blood flow through the mitral valvular.

4. Blood clot reduces blood flow through the mitral valve.

5. Adverse effect of fenfluramine and phentermine diet drug combination causes the valve to thicken by fibrosis and calcification.





Signs and Symptoms of Valvular Mitral Stenosis


1. In severe mitral stenosis, on auscultation, there are four typical findings including: an accentuated S1, an opening diastolic snap, a mid-diastolic rumble noted best at the apex (in sinus rhythm, followed by presystolic accentuation), and an increased pulmonic S2 intensity associated with pulmonary.

2. Exertional dyspnea: the narrowing mitral valvular decreases blood filling into the ventricles. Decreased volume in ventricle decreases SV and CO. Supply does not meet demand,causing exertional dyspnea, congestive heart failure occur if not treated properly.

3. The mitral valve is narrowed, causing backward flow of volume from the left atrium into the lungs, resulting in exertional dyspnea.

4. Orthopnea, Atrial fibrillation.

5. Nocturnal dyspnea: when lying down, all the blood that pools in the extremities during the day returns to the heart. This causes more fluid in the lungs.





Diagnostic Test for Valvular Mitral stenosis

1. Echocardiography is used in the evaluation of mitral stenosis to : quantify the valve area and gradient, to quantify the degree of mitral insufficiency, to define the degree of left atrial enlargement, to assess mitral annular calcification, to assess pulmonary artery pressures and degree of pulmonary hypertension, to evaluate right- and left-sided ventricular function.
2. Electrocardiography (EKG): reveals left atrial enlargement, right ventricular hypertrophy, atrial fibrillation.
3. Chest radiography correlates with the degree of mitral stenosis.
4. Cardiac catheterization to determine location and extent of blockage, catheterization is used less in diagnosis of mitral stenosis as echocardiography techniques improve.




Treatment

1. Percutaneous Mitral Catheter Balloon Valvuloplasty.

2. Prevention of rheumatic fever, Oxygen: increases oxygenation.

3. Digoxin, lowsodium diet, diuretics, vasodilators, ACE inhibitors: treat left-sided heart failure.


4. Prophylactic antibiotics before and after surgery and dental care: prevent endocarditis.

5. Anticoagulants, Nitrates, Cardioversion: converts atrial fibrillation to sinus rhythm.

6. Percutaneous Mitral Catheter Balloon Valvuloplasty.

7. Percutaneous mitral catheter balloon valvuloplasty is an alternative, less invasive procedure than surgical treatment for mitral stenosis. Balloon valvuloplasty is performed in the cardiac catheterization laboratory by a cardiologist experienced with invasive techniques. A small balloon valvuloplasty catheter is introduced percutaneously at the femoral vein and passed into the right atrium. The catheter is then directed transseptally and positioned across the mitral valve.

8. Surgical Treatment. Surgical replacement of the mitral valve is required when there is severe mitral regurgitation coexisting with mitral stenosis. Although some valves with mitral stenosis may be repaired by open commissurotomy and reconstruction, heavily calcified rheumatic mitral valves often are beyond the point of repair. The usual prosthetic valve of choice in mitral stenosis is a mechanical prosthesis because patients already require life-long anticoagulation because of atrial fibrillation. For young women who wish to become pregnant, a bioprosthesis may be recommended.



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B. Mitral Insufficiency/Regurgitation

The mitral valvular can not close properly during ventricular contraction or systole, causing backward flow of blood during systole. This backward flow can cause heart failure. Or we can say, valvular mitral valve regurgitation is occurs as the result of inadequate closure of the mitral valve, allowing regurgitant flow back into the left atrium during each left ventricular systole.




Causes of Valvular Mitral Insufficiency/Regurgitation


1. Infective endocarditis or rheumatic heart disease causes inflammation and damages the valve.
2. Coronary artery disease: ischemia and/or necrosis of the heart muscle can cause damage to the supporting structures of the mitral valve, impeding proper closure of the valve.
3. Aging: over time, degenerative changes can weaken the valve.
4. Cardiomyopathy
5. Left Ventricle dilatation,etc.





Signs and Symptoms Mitral valve Regurgitation


Patient with in acute mitral regurgitation, symptoms progress rapidly. Symptoms are like left ventricular failure. The patient is usually tachycardic to compensate for the reduced forward stroke volume. Patients are dyspneic secondary to pulmonary congestion and edema.

During the compensatory phase of chronic mitral regurgitation, patients may be relatively asymptomatic for years.

Fatigue and weakness, Pansystolic murmur, Palpitations, Angina





Diagnostic Test for Valvular Mitral Regurgitation

1. Auscultation and Holter monitor for 24 hours: may show arrhythmia.

2. Transthoracic echocardiography can identify the structural cause of the mitral regurgitation as well as gauge left atrial size.

3. Other s please see diagnostic test for mitral stenosis.






Treatment

1. Anticoagulants: to prevent blood clots.
2. ACE inhibitors: to treat mild heart failure.
3. Valvuloplasty: to repairs the faulty valve
4. Valve replacement: with a prosthetic valve



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C. Mitral Valve Prolapsed

The valvular mitral cusps bulge into the left atrium when the left ventricle contracts, Allowing leakage of small amount of blood into the atrium. Peoples who with mitral valve prolapse may have mitral regurgitation ranging in severity from none to severe. Persistent billowing of the valve causes stress to the underlying chordae and papillary muscles. Progressive mitral valvular degeneration can result in increasingly severe mitral regurgitation. If chordal rupture happen, severe mitral regurgitation develops.



Causes of Valvular Mitral Prolapsed

1. Connective tissue disorders (systemic lupus erythematosus,Marfan’s syndrome): the chordae tendineae can become elongated, which allows the mitral valve leaflets to open backward into the atrium during systole.

2. Congenital heart disease: autosomal dominant inheritance seen in young women.

3. Acquired heart disease (coronary artery disease, rheumatic heart disease):causes valve bulge due to inflammation process.

4. The most common cause of mitral valve prolapse is myxomatous degeneration. Marfan's syndrome, Ehlers-Danlos syndrome, rheumatic heart disease, and ischemic papillary muscle dysfunction also cause mitral valve prolapse.





Sign and Symptoms of Mitral Valve Prolapsed

Fatigue and weakness, why? Because, during ventricular contraction the blood backs up into left atrium. The left side of heart, both the atrium and ventricles becoming hypertrophy and dilate. Cardiac output also will decreases. There is an imbalance between supply and demand, causing fatigue .


Angina, Palpitations, Migraine headaches, Dizziness, Orthostatic hypotension, Mid-to-late systolic
click; late systolic murmur.

Most patients with mitral valve prolapse are asymptomatic. Patients may complain of sharp, localized chest pain that is usually brief in duration.




Diagnostic Test for Valvular Mitral Regurgitation

1. Echocardiography plays a key role in the diagnosis of mitral valve prolapse. Abnormal systolic motion of one or both of the mitral valve leaflets superior to the annular plane can be seen. Doppler echocardiography gives additional evidence of valve regurgitation.

2. Electrocardiography is nondiagnostic. The ECG may be normal or have nonspecific ST-T–wave changes in the inferior leads (II, III, and aVF) and occasionally in the anterolateral leads (V4 through V6). The ST-T–wave changes may become more notable with exercise. Some have suggested that these changes occur secondary to ischemia from increased tension on the papillary muscles.41 Premature atrial and ventricular complexes may also be identified Exercise testing may be used to help rule out the etiology of the chest pain.

3. Auscultation: to reveal clicking sound.

4. Echocardiography: to show the prolapsed and to role out the severity of regurgitation if present.

5. Electrocardiography (EKG): may reveal atrial or ventricular arrhythmia.

6. Holter monitor for 24 hours: may will show arrhythmia.





Treatment

1. Decreased caffeine, alcohol, tobacco, stimulant intake: relieve palpitations
2. Fluid intake: to maintain hydration
3. Beta-blocker: to slow heart rate; reduces or relieve palpitations
4. Antibiotics should be given before medical procedures: prevention against bacterial infection of heart valve.
5. Anticoagulants: to prevent thrombus formation or blood clot
6. Antiarrhythmia drugs to prevent arrhythmias.


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D. Aortic Valve Stenosis

Aortic stenosis is characterized by obstruction of the left ventricular outflow tract or Narrowing of the aortic valve opening that wiil increase vascular resistance for pumping blood from the left ventricle to the aorta. The left ventricle hypertrophies and weakens, leading to left-sided heart failure.



Causes of Valvular Aortic Stenosis

Aortic stenosis typically progresses over a period of years. As the valve cusps become less mobile, the valve orifice decreases in size, resulting in an increasingly higher left ventricular systolic pressure necessary to pump blood across the stenosed valve. It will increase left ventricular afterload results first in compensatory concentric left ventricular hypertrophy.

Rheumatic fever causes inflammation of the cusps that leads to scarring; usually accompanied by mitral stenosis and leakage.

Birth defect: valve with two cusps instead of usual three; valve with abnormal funnel shape, calcium accumulates causing the valve to become stiff and narrow.

Atherosclerosis: lipids can increase calcium accumulation of the heart valves.





Signs and Symptoms of Valvular Aortic Stenosis


The people who has mild to moderate aortic valve stenosis are usually asymptomatic. As severe aortic stenosis develops, the most common initial complaint is dyspnea on exertion, followed by angina and near syncope or syncope.


If not treat properly it develop to pulmonary congestion becous leftsided heart failure occur.

Harsh, rasping, crescendo-decrescendo systolic murmur caused forced blood flow across stenotic valve.




Diagnostic Test : (see mitral stenosis)






Treatment



1. Low-sodium, low-fat low-cholesterol diet: to treats left-sided heart failure
2. Diuretics: to treat leftsided heart failure
3. Periodic noninvasive evaluation: to monitors severity of valve narrowing
4. Cardiac glycosides: to control atrial fibrillation
5. Antibiotics before medical, dental, surgical procedures: prevent endocarditis
6. Percutaneous balloon aortic valvuloplasty: to reduces degree of stenosis
7. Aortic valve replacement: to replaces diseased valve



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E. Aortic Valve regurgitation/ Insufficiency

Leakage of the aortic valve. Each time the left ventricle relaxes, blood leaks back into it. (Atria are contracting while ventricles are relaxing).




Causes of Valvular Aortic regurgitation/ Insufficiency

Aortic regurgitation may be due either to intrinsic abnormalities of the aortic valve leaflets or disease of the aortic root. In rheumatic fever and endocarditis, the aortic leaflets are directly affected.

In congenitally bicuspid valves, the larger cusp may become redundant, resulting in diastolic prolapse and progressive aortic regurgitation. The aortic valve may also become incompetent due to aortic root dilation. As the aortic root dilates, the aortic annulus becomes so large that the valve cusps no longer approximate, resulting in regurgitation.




Signs and Symptoms

1. Most of the patients with chronic aortic regurgitation are often asymptomatic for few years. But its usually common symptoms of aortic regurgitation include fatigue and exertional dyspnea.
2. Diastolic murmur blood is backing up into left ventricle from aorta during diastole and it will make some changing in the papillary muscle within few years.So you will hear heart sound S1, S2, then the murmur, e.g.,lub, dub, whoosh.
3. Left-sided heart failure such as nocturnal dyspnea, S3, pink frothy sputum, cough, crackles, orthopnea, tachycardia, restlessness.





Diagnostic Test

1. Echocardiography use for identifying the cause of aortic regurgitation. Echocardiography can indicate left ventricular volume overload by the increased internal diameter of the ventricular chamber during both systole and diastole. Doppler echocardiography is the best noninvasive means to detect aortic regurgitation. Transesophageal echocardiography is especially useful in imaging both the ascending and descending aorta in patients with suspected aortic dissection.

2. Cardiac catheterization should be performed to visualize and quantify the extent of regurgitation. However, physical findings and noninvasive tests are sufficient to role out the diagnosis of aortic insufficiency. In patients are suspected CHD, coronary angiography should be done. In patients with aortic root dilation, aortic root angiography may be done concurrently with coronary angiography.

3. Radionuclide imaging can be used to estimate ejection fraction and determine myocardial perfusion defects in patients with concomitant CHD.




Treatment


Anyone who have asymptomatic aortic regurgitation should be received appropriate antibiotic prophylaxis as well as afterload reduction with vasodilators.
Vasodilators usfull to reduce systolic load and regurgitant volume Valve replacement with prosthetic valve.

Low-sodium diet, Diuretics, Nitroglycerin.





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