What is anomalous left coronary artery from the pulmonary artery (ALCAPA) and its significance?
In a normal heart, both coronary arteries arise (branch) from the aorta and supply blood to heart muscle. In ALCAPA the left coronary artery arises from the pulmonary artery instead of the aorta.
Pulmonary artery is a low pressure system as compared to aorta. In setting of ALCAPA, following changes can damage heart muscle and ultimately death of cells.
- Blood in pulmonary artery is deoxygenated ( lacks oxygen). Hence, in ALCAPA though blood is supplied to heart, it does not have adequate amount of oxygen to fulfill demnd.
- As a result of communication with low pressure pulmonary artery, blood flowing through blood vessels is shunted and not supplied to heart muscles.
These factors leads to dysfunction and damage of heart muscles and ultimately death.
Signs and symptoms of ALCAPA
In an infant, ALCAPA symptoms can include:
- Blue or purple tint to gums, tongue, skin and nails (cyanosis)
- Poor eating and poor weight gain
- Crying with feeds
- Rapid breathing or shortness of breath
- Profuse sweating, especially with feeding
- More sleepiness than normal
- Unresponsiveness (the baby seems “out of it”)
- Heart murmur – the heart sounds abnormal when a doctor listens with a stethoscope
Testing and diagnosis
ALCAPA cannot be detected during pregnancy with fetal echocardiography. In most cases ALCAPA is diagnosed in the first one to two months of life, after a parent or pediatrician notices symptoms. In rare cases, the child doesn’t have noticeable ALCAPA symptoms until he or she is a toddler or older.
Diagnosis of ALCAPA may include:
- Chest X-ray. This usually shows an enlarged heart.
- 2D Echocardiogram – In hands of expert, this is the diagnostic test. However, because coronary arteries are sometimes difficult to image, a cardiac catheterization and sometimes a cardiac CT are used .
- Electrocardiogram (EKG or ECG) –. This may show evidence of myocardial ischemia and infarction (heart attack).
- Cardiac catheterization: It is the diagnostic test though used infrequently.
Treatments for ALCAPA
Main aim of surgery is to restore oxygenated blood supply to heart. Various surgical options include
- Coronary transfer : Detaching the left coronary artery from the pulmonary artery and suturing it into the aorta where it is normally .
- Takeuchi surgery: Creating a tunnel from the aorta to the anomalous left coronary artery, and then closing the connection between the left coronary artery and the pulmonary artery.
- Coronary bypass graft : Creat connection between internal mammary artery or subclavian artery and the left coronary and close abnormal connection between left coronary and pulmonary artery
After surgery patients are kept in intensive care unit for recovery.
Outlook
After surgery, most patients with ALCAPA will experience a good quality of life. Many children who were born with ALCAPA do very well and don’t have any restrictions to school, activity or sports, though they all will need life-long care by a cardiologist. Some will have to remain on medicine, but many will be able to stop taking medicines within weeks or months of surgery.
Long term Follow-up care
To ensure adequate blood supply to heart and to know working condition of heart, it is necessary to follow up with paediatric cardiologist at regular interval. Patients are followed up well into their thirties and forties to detect any late complication well in time. These patients are at high risk of coronary stenosis, myocardial ischemia and arrhythmia ( abnormal and irregular heart rhythm)