Anomalous Coronary Artery (ACA)

What Is Anomalous Coronary Artery?

An anomalous coronary artery (ACA) is a coronary artery that has an abnormality or malformation. The malformation is congenital (present at birth) and is most often related to the origin or location of the coronary artery. However, there may be other defective areas in the coronary artery. Likewise, it may affect the overall size and shape of the affected coronary artery or arteries. ACA may also occur along with other congenital heart defects.

This condition may also be called congenital coronary artery anomaly (CAA).

Although they are present at birth, ACAs are often not diagnosed until late adolescence or adulthood, because of the lack of symptoms or because symptoms may not be recognized as being caused by ACA. Teens or adults with unknown ACA may have an initial episode of chest pain, heart failure, or even sudden cardiac death before the condition is recognized.

Anatomy of the coronary arteries

The main function of the coronary arteries is to supply blood to the heart muscle. Like all other tissues in the body, the heart muscle needs oxygen-rich blood to function, and oxygen-depleted blood must be re-circulated to the lungs. The coronary arteries are made up of two large branches called the right and left coronary arteries. The left coronary artery system branches into the circumflex artery and the left anterior descending artery.

The two main coronary arteries are the left main and right coronary arteries. The left main coronary artery (LMCA), which divides into the left anterior descending artery and the circumflex branch, supplies blood to the left ventricle and left atrium. The right coronary artery (RCA), which divides into the right posterior descending and acute marginal arteries, supplies blood to the right ventricle, right atrium, and sinoatrial node (cluster of cells in the right atrial wall that regulates the heart's rhythmic rate).

Additional arteries branch off the two main coronary arteries to supply the heart muscle with blood.

These include the following:

• Circumflex artery (Cx). The circumflex artery branches off the left coronary artery and encircles the heart muscle. This artery supplies blood to the lateral side and back of the heart.
• Left anterior descending artery (LAD). The left anterior descending artery branches off the left coronary artery and supplies blood to the front of the left side of the heart.

Smaller branches of the coronary arteries include: acute marginal, posterior descending (PDA), obtuse marginal (OM), septal perforator, and diagonals.

Why are the coronary arteries important?

Since coronary arteries deliver blood to the heart muscle, any coronary artery disorder or disease can potentially reduce the flow of oxygen and nutrients to the heart, which may lead to a heart attack or death.