Aortic Regurgitation

Aortic Regurgitation

The aortic valve is between the heart's left ventricle (lower chamber that pumps blood to the body) and the aorta (the large artery that receives blood from the heart's left ventricle and distributes it to the body). Regurgitation means the valve doesn't close properly, and blood can leak backward through it. This means the left ventricle must pump more blood than normal, and will gradually get bigger because of the extra workload. Aortic regurgitation can range from mild to severe. Some people may have no symptoms for years. But as the condition worsens, symptoms will appear. These can include

• fatigue (especially during times of increased activity)
• shortness of breath
• edema (retention of fluid) in certain parts of the body such as the ankles
• heart arrhythmias (abnormal heartbeats)
• angina pectoris (chest pain or discomfort caused by reduced blood supply to the heart muscle)

What causes aortic regurgitation?

Aortic regurgitation can be caused by several things. It may be due to a bicuspid aortic valve. This is a congenital (existing at birth) deformity of the valve. In it, the valve has two cusps (flaps) rather than the normal three cusps. It can also be found in other kinds of congenital heart disease. Aortic regurgitation can also be caused by infections of the heart, such as rheumatic fever or infective endocarditis. Diseases that can cause the aortic root (the part of the aorta attached to the ventricle) to widen, such as the Marfan syndrome or high blood pressure, are other causes.

What should be done?

Patients with mild aortic regurgitation who have few or no symptoms need to see their physician regularly. As conditions worsen, medications may be used. These drugs can help regulate the heart rhythm, rid the body of fluids to control edema, and/or help the left ventricle pump better.
Serious cases may require surgical treatment. This involves replacing the diseased valve with an artificial one.
People with aortic regurgitation are at increased risk for developing an infection of the heart valve or lining of the heart (endocarditis). In the past, the American Heart Association has recommended that patients with aortic regurgitation take a dose of antibiotics before certain dental or surgical procedures. However, our association no longer recommends antibiotics before dental procedures except for patients at the highest level of risk for bad outcomes from endocarditis, such as

• patients with a prosthetic cardiac valve,
• patients who have had endocarditis before,
• patients with certain kinds of congenital heart disease, or
• heart transplant patients who develop a problem with a heart valve. 

Also, the American Heart Association no longer recommends routine antibiotics to prevent endocarditis in patients undergoing gastrointestinal (GI) or genitourinary (GU) tract procedures
.

Frequency

United States

Rheumatic fever and syphilis used to be major causes of aortic regurgitation, but these diseases have diminished in recent years because of the introduction of new antibiotics.

Mortality/Morbidity

• Three fourths of patients with significant aortic regurgitation survive 5 years after diagnosis; half survive for 10 years. Patients with mild-to-moderate regurgitation survive 10 years in 80-95% of the cases.
• Average survival after onset of congestive heart failure (CHF) is less than 2 years.
• Acute aortic regurgitation is associated with significant morbidity, which can progress from pulmonary edema to refractory heart failure and cardiogenic shock.

Age

Chronic aortic regurgitation often begins in the late 50s and is documented most frequently in patients older than 80 years.

History

• General

  • The clinical signs of aortic regurgitation are caused by forward and backward flow of blood across the aortic valve, leading to increased stroke volume.
  • The degree of regurgitation is determined by the degree of valvular incompetence; left ventricular compliance; and end-ventricular, end-diastolic volume.
• Acute aortic regurgitation: Symptoms are manifestations of cardiovascular collapse.

  • Weakness
  • Severe dyspnea
  • Hypotension
  • Angina
• Chronic aortic regurgitation

  • Exertional dyspnea
  • Nocturnal dyspnea
  • Orthopnea
  • Diaphoresis
  • Abdominal discomfort
  • Uncomfortable awareness of heartbeat
  • Palpitations

Differentials

• Abdominal Trauma, Blunt
• Acute Coronary Syndrome
• Congestive Heart Failure and Pulmonary Edema
• Endocarditis
• Mitral Regurgitation
• Mitral Stenosis
• Myocardial Infarction

Laboratory Studies

• CBC
• Prothrombin time (PT)/activated partial thromboplastin time (aPPT)
• Type and screen
• Electrolytes
• Myocardial muscle creatine kinase isoenzyme (CK-MB)
• Lactate dehydrogenase panel
• Isoenzymes
   

  Emergency Department Care

  • General

    • Provide adequate airway management.
    • Intubate when necessary.
    • Consider prompt surgical intervention in acute aortic regurgitation.
  • Acute aortic regurgitation

    • Administer a positive inotrope (eg, dopamine, dobutamine) and a vasodilator (eg, nitroprusside). Rarely, administration of cardiac glycosides (eg, digoxin) for rate control may be necessary.
    • Avoid beta-blockers in the acute setting.
    • Administration of vasodilators may be appropriate to improve systolic function and to decrease afterload.
  • Chronic aortic regurgitation

    • Consider antibiotic prophylaxis for patients with endocarditis when performing procedures likely to result in bacteremia.
    • Administration of pressors and/or vasodilators may be appropriate.
  • Hemodynamically significant aortic regurgitation may require surgical intervention according to the following criteria:

    • Cardiac-thoracic ratio >0.64
    • Fractional shortening < 25-29%
    • End-systolic diameter >55 mm
    • End-diastolic radius to myocardial wall thickness ratio >4.0
    • Ejection fraction < 0.45
    • Cardiac index < 2.2-2.5 L/min/m²

   

  What are the treatments for aortic regurgitation?

  If the backflow of blood is mild and you have no symptoms then you may not need any treatment. If you develop symptoms or complications, various medicines may be advised to ease the symptoms. Surgery may be advised if symptoms become worse.

  Medication

  Medication may be advised to help ease symptoms of heart failure if heart failure develops. For example:
  

  • Diuretics (water tablets) usually help if you are breathless. They make the kidneys produce more urine. This gets rid of excess blood and fluid which may build up in the lungs or other parts of the body with heart failure.
  • Angiotensin-converting enzyme (ACE) inhibitors are medicines which help to reduce the amount of work the heart does and to ease symptoms of heart failure.

  Valve replacement surgery

  This may be with a mechanical or a tissue valve. Mechanical valves are made of materials which are not likely to react with your body, such as titanium. Tissue valves are made from treated animal tissue, such as valves from a pig. If you need surgery, a surgeon will advise on which is the best option for your situation.
  
  Surgical treatment has greatly improved the outlook in most people with more severe regurgitation. Surgery to replace the valve has a very good success rate. The outlook is good if the valve is treated before the heart becomes badly damaged.

  Antibiotics to prevent endocarditis

  Antibiotics used to be offered to all people with heart valve disease before dental treatment and some surgical procedures to prevent the development of endocarditis. However, the National Institute for Health and Clinical Excellence (NICE) issued guidance in 2008 which advised that people at risk of endocarditis only need to take antibiotics if they actually have an infection at the time that dental or surgical procedures are undertaken.

Posted in: Aortic Regurgitation,CVS