What is Anomalous Coronary Artery Disease?

What Is It?

An anomalous aortic origin of a coronary artery (AAOCA) is a condition in which one of the two coronary arteries arises from an uncommon place on the aorta (blood vessel that supplies blood to the body). Most often people are born with two coronary arteries, a right and a left.

The coronary arteries are the main blood vessels that supply oxygenated blood to the heart muscle. This allows it to pump (squeeze) the right way. The coronary arteries are the blood vessels that often get clogged with plaque / fat in later life. This can lead to a heart attack.

Children can be born with either an AAORCA or an AAOLCA:

• AAORCA is a condition in which the right coronary artery comes off the left side of the aorta.
• AAOLCA is a condition in which the left coronary artery comes off the right side of the aorta.

We do not know how often this happens. It is believed to happen in less than 1 percent of people.

Presentation

AAOCA does not present the same in all people. Some people have symptoms such as:

• Chest pain
• Shortness of breath
• Fainting
• Feeling dizzy
• Feeling that their heart is not beating right during physical activity

For some patients, the first symptom is aborted sudden cardiac arrest during physical activity.

People who have any of these symptoms need to promptly see a cardiologist (heart doctor).

AAOCA does not cause a heart murmur.

Diagnosis

Most people are told they have AAOCA when the abnormal location of the coronary is found by chance when they are having imaging of their heart done for some other reason (such as an unrelated heart murmur, workup for starting chemotherapy, or an abnormal EKG).

Testing that may be used to diagnose AAOCA:

Echocardiogram (Echo): An ultrasound of the heart. This allows heart doctors to see the structures, coronaries, and function (squeeze) of the heart. An echo is a non-invasive test that can be done in clinic to help find out if a patient has AAOCA. The test often takes less than 45 minutes to do. An AAOCA diagnosis can often be made from this test.

Electrocardiogram (EKG): A test that looks at the electrical pathway of the heart. The patient is hooked to 12 leads placed on the chest with stickers. The EKG looks for heart rhythm problems. The test often takes less than 10 minutes. EKG changes are not always seen in patients with AAOCA on an EKG.

Exercise test: Also known as a stress test or graded exercise test (GXT). An exercise test is a useful tool for gaining facts about a child's heart function and fitness. It looks for lack of oxygenated blood flow down the coronary arteries (ischemia) by EKG changes with exercise. This test can also be given with an echo and/or an IV treatment of a cardio-specific radioisotope (sestamibi). Adding these tests during an exercise test can help to find out how the blood flows through the coronary arteries.

Cardiac MRI or CT scan: Cardiac MRIs and CTs are done on MRI machines that have special software and cardiac equipment. Both can help show the coronary artery structure in a better way. This can help confirm the diagnosis. There is no radiation with an MRI. An MRI can also be done with IV medicine. This can help figure out if the blood flow through the coronary arteries is good enough.

Risks and Treatment

The most recent data show the risk of sudden aborted cardiac arrest is thought to be one in 1 million though this is thought to be under reported. The exact reason for the ischemia (lack of oxygenated blood to the heart muscle leading to a heart attack) is not known.

A cardiac risk assessment is done to figure out how to manage this.

Since AAOCA is an abnormal coronary artery structure, it cannot be treated with medicine. Surgery is advised for treatment. This is decided based on the type of coronary anomaly and risk assessed from the stress testing. In patients with AAORCA, surgery is advised based on symptoms such as passing out, abnormal heart rhythms, chest pain with activity or ischemia noted on stress testing.

Most children older than 10 years of age with AAOLCA are referred for surgery even if they do not have symptoms. This is due to the increased risk of sudden cardiac death. The most common non-surgical strategy includes placing a limit on activity. The doctor will decide what is best based on the risk assessment.

Follow-Up

All patients with AAOCA will be followed by a heart doctor for their lifetime. Their follow-up will be based on which treatment options are chosen. It is normal for patients who do not have a surgical repair to have a yearly follow-up. This follow-up includes testing such as an echo, EKG and exercise test each one to three years.

Patients that have surgery for repair are watched more closely. Their follow-up is based on assessment and review of testing after their surgery.