Aortic Insufficiency - Causes, Symptoms, Diagnosis, and Treatment

What Is Aortic Valve Insufficiency?

Typically, the heart consists of four valves and four chambers that aid blood circulation to the body parts. The valves have leaflets (cusps) that open and close during circulation. When the aortic valve's leaflets do not close tightly, it results in the backflow of the blood to the left ventricle (chamber of the heart). It leads to a condition called aortic valve insufficiency or aortic regurgitation.

What Is the Pathophysiology of Aortic Valve Insufficiency?

• Acute Aortic Insufficiency: Acute aortic insufficiency causes a sudden increase in left ventricular end-diastolic volume, leading to a rapid rise in left ventricular diastolic pressure, premature mitral valve closure, and mitral regurgitation. Pulmonary edema may result.

• Chronic Aortic Insufficiency: In chronic aortic insufficiency, the left ventricle compensates through eccentric hypertrophy and dilation, allowing increased stroke volume. However, over time, increased volume and pressure lead to remodeling, fibrosis, and decreased compliance, reducing stroke volume.

What Causes Aortic Insufficiency?

Aortic valve insufficiency may occur suddenly or can develop gradually. The causing factors are as follows:

• Heart valve defects: Generally, three cups in the aortic valve open and close during circulation. Sometimes there are only two cusps (bicuspid) present in a few individuals by birth (congenital), leading to leakage of blood back to the ventricle.

• Infections in any body system can spread through blood and cause inflammation of the heart chambers and valves, leading to endocarditis.

• Rheumatic fever associated with bacterial infection of the throat (strep throat) leads to narrowing of the aortic valve, referred to as rheumatic heart disease.

• Narrowing of the valve occurs due to calcium build-ups that lead to its blockage, called aortic stenosis.

• Injury or trauma to the aortic valve also causes backward blood flow.

• Certain medications like Bromocriptine (Dopamine agonists) increase the stress on the valve, leading to the thickening of its walls.

• Other conditions like systemic lupus erythematosus, Marfan's syndrome, etc., also cause aortic valve regurgitation.

What Are the Symptoms of Aortic Insufficiency?

There may be no symptoms for years, and they may develop gradually or suddenly. It includes the following:

• Chest pain or discomfort that increases with exercise.

• Fatigue.

• Shortness of breath.

• Swelling in the ankles and feet.

• Variable or irregular pulse rate.

• Fainting.

• Sounds are heard during a heartbeat (murmur).

• Weakness.

• Irregular pulse.

What Are the Risk Factors for Aortic Insufficiency?

The various factors that increase the occurrence of aortic regurgitation are:

• Increase in age.

• Increase in blood pressure levels (hypertension).

• Infections in the body.

• Other heart valve defects.

How to Diagnose Aortic Valve Insufficiency?

The various methods that aid in the diagnosis of aortic insufficiency are:

• A Complete Physical Examination of the patient, along with the medical history, is performed. The patients possess symptoms like coughing, pounding heartbeat, chest pain, and shortness of breath. The other signs that are diagnosed during physical examination are:

1. Blushing and washing out of blood in smaller vessels (capillaries) on the fingernail beds.

2. Pounding pulses like pistol shots are heard due to the compression of the arteries in the lower leg.

3. Wagging of the head during every heartbeat.

4. Rumbling heart murmurs are heard through a stethoscope.

5. Bobbing of the uvula (the soft tissue that hangs at the end of the soft palate) is observed, accompanying heart muscle contraction.

6. Bound pulses along the arms and legs.

• An Aortic Angiogram is an imaging method used to diagnose any defects in the aorta and observe the flow of blood in the aortic vessel.

• Chest Radiograph allows the identification of any enlargement of heart muscles.

• An Echocardiogram test is essential in diagnosing aortic valve insufficiency. It detects the amount of blood in the left chamber of the heart and blood flow along the aorta.

• Cardiac Catheterization measures the flow of blood in the heart's valves, chambers, and blood vessels. A thin and hollow tube (catheter) is inserted into the artery of the legs or arms, and contrast dyes are injected into the catheter. It will help in assessing the blood flow to the heart.

What Is the Differential Diagnosis?

The conditions that often lead to misdiagnosis of aortic valve regurgitation are:

• Coronary heart disease is a condition wherein calcium builds up in the arteries (which supply oxygen-rich blood to the heart muscles), leading to narrowing and blockage.

• Pulmonary regurgitation is a valve disease on the right side of the heart that pumps blood to the lungs. The pulmonary valve does not close tightly, leading to the backflow of blood to the heart's right chamber. In this condition, murmurs are heard during the relaxation of the heart muscles, similar to aortic valve insufficiency. Abnormal heart sounds increase during expiration in patients with aortic insufficiency. In contrast, the murmur increases during inspiration in pulmonary regurgitation.

What Is the Treatment for Aortic Insufficiency?

• Regular monitoring of the patient is essential in case of mild aortic insufficiency.

• Anti-hypertensive medications like angiotensin-converting enzyme inhibitors and calcium channel blockers are suggested to reduce high blood pressure levels.

• Antibiotics are prescribed to treat the infections that cause endocarditis.

• Transcatheter aortic valve replacement is a surgical procedure done to remove the defective aortic valve, and it is replaced with an artificial valve. It is the widely preferred method in treating severe aortic insufficiency.

What Is the Prognosis of Aortic Insufficiency?

The prognosis for aortic insufficiency depends on symptom onset and disease progression. Asymptomatic patients generally have a good prognosis, while those with severe AR benefit from prompt valve replacement, although careful monitoring is essential.

What Are the Complications of Aortic Insufficiency?

Clinicians should consider potential complications in managing aortic insufficiency. While surgical correction remains the gold standard, the use of TAVR is evolving, but further studies are needed to assess its long-term outcomes.

How to Prevent Aortic Insufficiency?

There are no such appropriate preventive measures, but following precautionary steps like:

• Periodic checkups of the blood pressure, as the high blood pressure levels, can also cause aortic regurgitation.

• The nutritionist and physical therapist can help in suggesting a good diet and exercise.

• Treating strep throat with appropriate antibiotics is necessary. Strep throat can cause rheumatic fever if not treated properly.

Conclusion:

The outcomes of the treatment for aortic insufficiency are good. An increase in people's awareness of keeping an eye on their blood pressure level and other symptoms and early inspection with doctors can prevent the progression of the disease.