Anomalous Aortic Origin of a Coronary Artery (AAOCA)
What is anomalous aortic origin of a coronary artery?
Anomalous aortic origin of a coronary artery (AAOCA) is a rare condition in which both of the coronary arteries arise from the same aortic sinus. In a normal heart, the left coronary artery arises from the left aortic sinus and the right coronary artery from the right aortic sinus. In AAOCA, one of the coronary arteries takes off from the aorta (the large blood vessel that brings blood to the body) from the wrong side, and is routed through or around the heart in a way that can restrict blood flow to the heart muscle or cause a potentially lethal heart rhythm. On occasion, there is only one coronary artery that supplies the heart with blood.
AAOCA is a congenital condition: children are born with it, though it may not be diagnosed until they are adolescents or adults and many people may never know they have it.
Depending on which coronary artery takes off from the wrong aortic sinus (or from a single coronary) the path it takes through or around the heart, determines if there is little impact on your child’s risk of sudden cardiac death or if there is the potential for a serious adverse cardiac event.
AAOCA appears to occur in boys about three times as often as it occurs in girls.
Causes of AAOCA
Little is known about the causes of coronary anomalies such as AAOCA. The development of coronary arteries is complex, and mutations may occur at many different sites.
Signs and symptoms of AAOCA
Most children with AAOCA experience no symptoms.
Many young patients are diagnosed with AAOCA when an echocardiogram is performed for an unrelated reason, such as a murmur evaluation, as a follow up to an abnormal electrocardiogram, or as screening after a family member is diagnosed with a heart condition with hereditary risks.
For others, the first sign of the problem is sudden cardiac arrest, most often as a teenager or young adult while engaged in or just after vigorous exercise.
When symptoms are present, they may include chest pain, heart palpitations, dizziness or fainting during or just after physical activity.
Testing and diagnosis for anomalous aortic origin of a coronary artery
If a child or adolescent in your life shows any of the symptoms described above, an electrocardiogram is usually the first screening test. Even if the electrocardiogram is normal, which it commonly is, an echocardiogram should be done to look at the coronary artery origins and course they take around the heart. If the echocardiogram raises a suspicion of a coronary anomaly, a cardiac MRI or CTA is usually performed.
Once the diagnosis of AAOCA is confirmed, your child performs an exercise stress test, usually with a nuclear myocardial perfusion scan or stress echocardiogram. This test helps the doctors to determine if there is evidence of decreased blood flow to the heart muscle or abnormal rhythm during vigorous exercise.
Because AAOCA may have hereditary links, if your child is diagnosed with AAOCA, doctors will generally recommend that siblings have a screening echocardiogram.
Treatment for AAOCA
Treatment options depend on your child's diagnosis. Some children will not have any restriction from competitive athletics. Others may have restriction from vigorous exercise or competitive athletics but participation in gym class is permitted. In some cases, surgical repair is required.
The treatment recommendations are based on the coronary artery course, symptoms or signs concerning for decreased blood flow to the heart, and your child’s estimated risk of sudden cardiac arrest.
Factors weighed in the treatment recommendation include:
- Coronary anatomy, as revealed in diagnostic imaging – whether coronary arteries arise from the left or right aortic sinus, for example, and whether the path of the misplaced artery is such that stress on the heart is likely to restrict blood flow
- Symptoms – whether physical symptoms are experienced after activity or whether the child feels no effects from exercise
- Test results – especially the results of the exercise stress test, which can show how the heart performs during and after vigorous activity
The doctor and your family work together to develop a treatment plan that best meets your child’s needs.
Treatment recommendations from medical experts may vary because there is not yet an agreed-upon “correct” way to treat AAOCA. Studies are underway to measure the effectiveness of different treatment options for patients with different forms of the condition. Doctors at Children’s Hospital of Philadelphia (CHOP) are playing a leading role in this research.
Outlook for anomalous aortic origin of a coronary artery
There is no cure for AAOCA. Even after surgery, children with AAOCA will need cardiac follow-up for the rest of their lives.
With regular follow up, and by sticking with the treatment plan, patients are able to lead normal, healthy lives. Some may continue to play competitive sports while others may not.
Much remains unknown about AAOCA, and parents and families often have many questions. CHOP is setting up a parent/family support network to help families connect with and support each other.
Follow-up care for AAOCA
Follow-up care and monitoring for AAOCA is different for each child.
If no surgery is performed, an annual follow-up with a cardiologist is recommended. That visit will generally include an electrocardiogram, an echocardiogram and possibly an exercise stress test, depending on the patient’s age and level of activity.
If surgery is performed, close postoperative monitoring is needed. This will include electrocardiography and echocardiography soon after surgery, and an exercise stress test with myocardial perfusion imaging after three months. A cardiac MRI will be performed six to twelve months after surgery and approximately every three years after that.
Follow-up monitoring should be lifelong after diagnosis of AAOCA, no matter what treatment is provided.
Why choose CHOP?
CHOP is dedicated to treating patients with AAOCA, and doctors at CHOP are involved in the latest AAOCA research.
In 2014, CHOP established the Coronary Anomaly Management Program (CAMP). This is the only program in the Delaware Valley committed to treating patients with AAOCA. It comprises a multidisciplinary team of physicians and research specialists. Clinicians meet routinely to review patients seen in clinic or sent for a second opinion. CHOP also is leading the way with research in AAOCA. CHOP doctors are enrolling patients in research projects aimed at learning more about AAOCA and the best way in which our patients should be managed.