Heart Valve Regurgitation

What Is Regurgitation?

Regurgitation refers to the leakage in the heart valves. The heart comprises four valves that open and close and allow the blood to flow through it. But sometimes, the blood may remain in one valve or get leaked out due to the backflow of the blood in the opposite direction, or the valves do not close completely and leak the blood, causing heart valve regurgitation or valve insufficiency. There are four types depending on which of the valves are affected -

• Mitral regurgitation.

• Aortic regurgitation.

• Tricuspid regurgitation.

• Pulmonary regurgitation.

What Are the Causes of Heart Valve Regurgitation?

The causes of the heart valve regurgitation depend on the onset of the condition -

1. Acute:

• Heart attack.

• Endocarditis.

• Enlarged heart.

• Enlarged aorta.

2. Chronic:

• Mitral valve prolapse.

• Rheumatic heart disease.

• Uncontrolled hypertension.

What Is Mitral Regurgitation?

Mitral regurgitation is the backflow of blood from the left ventricle to the left atrium during systole.

Causes of Mitral Regurgitation-

Chronic Mitral Regurgitation:-

• Rheumatic fever.

• Mitral valve prolapse.

• Infective endocarditis (damage to valve).

• Ischemic heart disease.

• Dilated cardiomyopathy (dilatation of ventricle or mitral valve ring).

• Connective tissue diseases.

Acute Mitral Regurgitation:-

• Infective endocarditis.

• Myocardial infarction (papillary muscle rupture).

• Trauma.

Pathophysiology of Mitral Regurgitation -

Mitral regurgitation leads to gradual dilatation of the left atrium. However, chronic volume overload leads to left ventricular dilatation. Eventually, the pressure in the left ventricle and left atrium rises, leading to breathlessness and pulmonary congestion. On the contrary, there is a sudden elevation of left atrium pressure in acute mitral regurgitation, causing severe pulmonary edema.

Clinical Features of Mitral Regurgitation -

The clinical signs of mitral regurgitation are -

• Feeling overtired (fatigue).

• Shortness of breath during exercise (exertional dyspnea).

• Breathing discomfort on lying down flat (orthopnea).

• Thromboembolic events (less common).

• Acute pulmonary edema.

• Excess abdominal fluid.

• Atrial fibrillation (irregular pulse).

• Systolic thrill in the mitral area.

• Auscultation:- Soft first heart sound and third heart sound.

• Pan systolic murmur in the mitral area - Raised pulmonary capillary pressure and raised jugular venous pressure.

• Tender hepatomegaly.

• Bilateral pitting pedal edema.

• Ascites.

Investigations for the Diagnosis of Mitral Regurgitation -

• ECG may reveal evidence of left atrium and left ventricular enlargement, right ventricular hypertrophy, and atrial fibrillation.

• Chest X-ray shows findings suggestive of the left atrium and left ventricle enlargement and pulmonary congestion.

• Echocardiography reveals structural abnormalities of the valves, size of cardiac chambers, pulmonary artery pressure, ventricular dysfunction, and presence of thrombi.

• Doppler echocardiography is needed to detect and estimate mitral regurgitation. Transesophageal echocardiography provides better information than transthoracic echocardiography.

• Cardiac catheterization is used to assess the severity of mitral regurgitation and to detect associated valvular lesions and coronary artery disease.

Treatment for Mitral Regurgitation -

1. Medical Treatment of Mitral Regurgitation:

• Restriction of physical activities that cause fatigue and breathlessness.

• Sodium restriction and diuretics are used to reduce pulmonary congestion.

• Digoxin is given to control ventricular rate in patients with atrial fibrillation and to improve ventricular systolic function.

• Vasodilators like ACE (angiotensin-converting enzyme) inhibitors are given in chronic mitral regurgitation to reduce regurgitation and improve forward output.

• Intravenous Nitroprusside or Nitroglycerine is useful in acute mitral regurgitation.

• Oral anticoagulant (Warfarin) is given to patients with a history of thromboembolic events or to those with atrial fibrillation.

• Prophylaxis should be given to all patients to prevent rheumatic fever.

• Prophylaxis for infective endocarditis should be given prior to procedures.

2. Surgical Treatment for Mitral Regurgitation -

• Mitral Valve Repair or Mitral Valve Replacement- Patients initially on medical therapy are watched for symptomatic worsening and radiological evidence of progressive cardiac enlargement or deteriorating cardiac function. In this case, surgery is indicated. Surgery includes the repair or replacement of the mitral valve.

• Acute mitral regurgitation due to endocarditis, myocardial infarction, and trauma often require emergency surgery. Prior to surgery, patients are stabilized by vasodilators or intra-aortic balloon counterpulsation, which reduces regurgitation by lowering systemic vascular resistance.

What Is Aortic Regurgitation?

Aortic regurgitation is called the backflow of blood from the aorta through an incompetent aortic valve into the left ventricle during diastole. It may be either due to valvular involvement or dilatation of the aortic root or both.

Causes of Aortic Regurgitation-

• Rheumatic fever.

• Endocarditis.

• Trauma.

• Congenital bicuspid aortic valve.

• Syphilis.

• Ankylosing spondylitis.

• Aortic dissection.

• Marfan syndrome.

• Hypertension.

• Syphilis.

Pathophysiology of Aortic regurgitation -

There is leakage of aortic valves in aortic valve regurgitation. The valves of the heart help the blood flow from the heart to the body. Usually, blood flow into the left ventricle is stopped by the aortic valves. But during aortic valve regurgitation, there is dilatation and hypertrophy of the left ventricle, making some blood leak back into the valve when the heart relaxes.

Clinical Manifestations of Aortic Regurgitation -

The patients remain asymptomatic for years; the following are the clinical features for aortic regurgitation -

• Palpitations, particularly on lying down, are generally an early symptom.

Later on, patients present with dyspnea on exertion followed by orthopnea.

• Angina may also occur frequently in severe aortic regurgitation.

• The presentations in acute severe aortic regurgitation are,

  • Pulmonary edema.

  • Tachycardia.

  • Cold extremities.

  • Hypotension.

  • Cyanosis.

  • Collapsing pulse.

  • Dancing carotids (prominent carotid arteries).

  • Quincke’s sign (alternate flushing and skin paling at the nail's root on pressure).

  • A pistol shot sounds over femoral arteries (Traube’s sign).

  • Duroziez sign (to and fro murmur over the femoral artery when compressed).

  • De Musset’s sign (head nodding with the pulse).

  • Increased pulse pressure (low diastolic pressure).

  • Hill’s sign - Systolic blood pressure in lower limbs is higher (>20 mm Hg) than in upper limbs.

  • Diastolic thrill at the left sternal border.

  • High-pitched blowing early diastolic murmur.

  • Other murmurs include an ejection systolic murmur at the aortic area, which radiates to the carotid artery, and a low-pitched mid-diastolic murmur over the mitral area (Austin Flint murmur).

  • Basal crackles in lungs.

  • Edema.

  • Hepatomegaly.

Investigations for the Diagnosis of Aortic Regurgitation -

• ECG shows evidence of left ventricular hypertrophy and ST-T changes.

• Chest x-ray reveals abnormal enlargement of the heart (cardiomegaly) and aortic root dilatation. Features of pulmonary congestion may be present.

• Echocardiography may reveal structural abnormalities of the valves, size of cardiac chambers, pulmonary artery pressure, ventricular dysfunction, and presence of thrombi. Doppler echocardiography is needed to assess the severity of aortic regurgitation.

• Cardiac catheterization is mainly required to detect the presence of coronary artery disease.

Treatment Modalities for Aortic Regurgitation -

Medical Treatment of Aortic Regurgitation:

• Strenuous physical activities should be avoided.

• Sodium restriction and diuretics are advised in the presence of congestive heart failure.

• Digoxin and vasodilators (ACE inhibitors) are given to improve ventricular systolic function in patients with left ventricular failure. Long-acting Nifedipine has been found to delay the need for surgery.

• An oral anticoagulant (Warfarin) is given if there is atrial fibrillation.

• Prophylaxis for infective endocarditis should be given prior to procedures. Recent guidelines recommend prophylaxis only if there is a prior history of endocarditis.

• Nitroprusside or Inotrope is given in acute aortic regurgitation to stabilize the patient before surgery.

• Treatment of precipitating or underlying causes (syphilis, endocarditis) should be commenced.

Surgical Treatment for Aortic Regurgitation:

• Aortic Valve Replacement or Aortic Root Repair- All symptomatic patients with chronic aortic regurgitation should be considered for aortic valve replacement. However, surgery may also be advisable in asymptomatic patients who show evidence of abnormal enlargement of the heart or deteriorating left ventricular function. Repair of aortic root abnormalities and aortic valve replacement should urgently be performed in patients with acute aortic regurgitation. Vasodilators or Inotropes may stabilize patients before surgery.

What Is Pulmonary Regurgitation?

It is usually associated with dilatation of the pulmonary artery due to pulmonary hypertension causing the valve to not close properly, with leakage of blood back into the heart.

It may complicate mitral stenosis as it is difficult to distinguish from aortic regurgitation (Graham Steell murmur) because of early diastolic murmur.

What Is Tricuspid Regurgitation?

Tricuspid regurgitation is common and is most frequently a result of right ventricular dilatation. It occurs due to an improperly formed right atrium and ventricle, making the blood flow back into the right atrium.

Causes of Tricuspid Regurgitation-

• Rheumatic heart disease.

• Endocarditis, particularly in injection drug users.

• Ebstein’s congenital anomaly.

• Chest injury.

• Genetic disorders.

• Infection in the lining of the heart.

• Due to some inserted devices like pacemakers.

Symptoms of Tricuspid Regurgitation-

• Tiredness.

• Edema.

• Hepatic enlargement due to venous congestion.

• The most prominent sign is a ‘giant’V wave in the jugular venous pulse (a cv wave replaces the normal x descent).

• A pansystolic murmur at the left sternal edge.

• Pulsatile liver.

Investigations for the Diagnosis of Tricuspid Regurgitation -

• Echocardiography may reveal dilatation of the right ventricle. If the valve has been affected by the rheumatic disease, the leaflets (tissue flaps of the valve) will appear thickened, and, in endocarditis, vegetations (bacterial growth on heart valves) may be seen.

• Ebstein’s anomaly is a congenital abnormality of the tricuspid valve, where the valve between the right atrium and ventricle is improperly formed, with consequent enlargement of the right atrium. It is commonly associated with tricuspid regurgitation.

Treatment for Tricuspid regurgitation -

• Tricuspid regurgitation due to right ventricular dilatation often improves when the cause of the right ventricular overload is corrected with diuretic and vasodilator treatment.

• Patients with normal pulmonary artery pressure tolerate isolated tricuspid reflux well.

• Valves damaged by endocarditis do not usually need to be replaced.

• Patients undergoing mitral valve replacement, who have tricuspid regurgitation due to marked dilatation of the tricuspid annulus, benefit from valve repair with an annuloplasty ring to bring the leaflets closer together.

• People with rheumatic damage may require tricuspid valve replacement.

Conclusion:

Heart valve regurgitation is a condition that involves the valves of the heart, which leak blood when extra strain is placed on the heart. It is a preventable condition by maintaining a healthy lifestyle, avoiding tobacco smoking and alcohol consumption, and practicing regular exercise and healthy eating habits. However, it can be manageable with the help of healthcare professionals.