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The vast majority of congenital heart defects have no known cause. A baby's heart begins to develop at conception, and is completely formed by eight weeks into the pregnancy. Congenital heart defects develop during this crucial first eight weeks of the baby's development. Specific steps must take place in order for the heart to form correctly. Often, congenital heart defects are a result of one of these crucial steps not happening at the right time.
ACA may be associated with other congenital heart defects, particularly transposition of the great arteries, tetralogy of Fallot, and certain forms of pulmonary atresia.
Why is anomalous coronary artery a concern?
ACA is of concern because there may be no indication that the condition is present until a severe event, such as chest pain, heart attack, or even sudden death occurs. A child or adult may have remained asymptomatic (free from symptoms), and be completely unaware that he or she had a problem.
Individuals with ACA involved in strenuous activity or athletics may be at risk for sudden death and may need to modify their exercise routines. Between 4 and 15 percent of young people who experience sudden cardiac death are found to have a coronary artery anomaly. ACA is the second most common cause of sudden death in young athletes.
It is also suspected that anomalous coronary arteries may pose risk for earlier development of coronary atherosclerotic disease.