The Aorta is the large artery arising from the heart, carrying blood to the rest of the body. In aortic regurgitation (AR), instead of blood moving from the heart to the aorta, there is a backflow of blood back into the heart due to defects in the aortic valve or dilatation in the origin of the aorta from the heart. Of the patients affected by AR, 75% are men.
Causes of Aortic Regurgitation
- Rheumatic heart disease: This is a condition affecting the heart and its valves as a consequence of a streptococcal sore throat. This is seen predominantly in developing countries where there are overcrowding and poor access to health care.
- Congenital bicuspid aortic valve: This is an abnormal valve with two leaflets (normal is three), that has been present since birth. Individuals with this condition have an increased risk of calcium deposition in the valve, making it stiff and allowing leakage of blood back into the heart.
- Calcification of the normal valve: With increasing age, wear and tear in the valve allows calcium deposition leading to stiffness and leakage.
- Infective endocarditis: This is an infection affecting the valves with the growth of organisms on the valve leaflets that can damage the valve.
- Marfan’s Syndrome: This is a congenital disorder with the weakening of the wall of the aorta leading to an increase in area at the origin of the aorta
- Aortic Dissection: This is a catastrophic condition where there is a splitting of the wall of the aorta with the entry of blood into the new space. If this extends towards the heart, it can lead to a severe AR with a high risk of death
Symptoms of Aortic Regurgitation
These symptoms can develop rapidly or progress slowly over a long period of time depending on the underlying cause for the AR. Additional symptoms may be present which can help to differentiate between the various causes of AR. The common symptoms are
- Shortness of breath
- Chest pain
- A pounding heartbeat
- Head pounding
Diagnosis of Aortic Regurgitation
The diagnosis is suspected based on the history of symptoms and is confirmed by the following
- Physical Examination: The doctor will look, feel, and listen to your chest and heart. An additional abnormal heart sound called a murmur is usually heard in AR.
- Electrocardiogram (ECG): This test records the electrical activity of the heart. It shows if there is any abnormal heart rhythm or if there is an enlargement of the heart
- Echocardiogram (echo): This test uses ultrasound waves to obtain an image of the heart in real-time. It helps to visualize the heart valves and to see the flow of blood across them. This helps to confirm the diagnosis of AR.
- Chest X-ray: This may show an increase in the size of the heart and the aorta. IT can also help to see if there is any fluid in the lungs as a result of the AR.
- Cardiac Catheterisation and Angiography: This test is invasive and uses a thin wire inserted into an artery or vein to reach the heart and make accurate measurements of the blood flow and pressure across the valve, to give additional information.
Treatment of Aortic Regurgitation
The treatment options vary depending on many factors. In a rapidly progressing AR with severe symptoms developing in a short span of time, immediate stabilization is indicated, followed by surgery within 24 hours.
- In a slowly progressing AR, the following options are considered
- Medical therapy: Drugs are used initially to help control symptoms and to control blood pressure. This is used in patients who are not candidates for surgery or as a means to optimize status prior to surgery
- Surgical aortic valve replacement (SAVR): This is the definitive treatment option in individuals with severe AR who are experiencing symptoms.
- Transcatheter aortic valve implantation (TAVI): This is an alternate procedure for those unable to undergo surgery. It is minimally invasive allowing the insertion of a wire containing an expandable valve into the heart through an artery. It is under trials for use in AR but is limited due to difficulties in anchoring the new valve.
Complications of Aortic Regurgitation
- Heart Failure: The backward flow of blood increases the pressures in the heart which leads it to fail.
- Pulmonary Hypertension: The increased pressure in the heart in turn elevates the pressures in the blood vessels in the lungs. This leads to pulmonary hypertension.
Prognosis of Aortic Regurgitation
Acute AR that is rapidly progressing leads to death unless treated immediately by surgery. Chronic AR that is gradually getting worse can finally lead to heart failure and death if not treated adequately. It is important to monitor individuals with AR at least annually to look for progression of the disease. Valve replacement surgery is beneficial to control symptoms and prevent mortality.