Atrioventricular canal defect (AVCD) surgery | Dr Samson Olori

What is AV canal defect?

Atrioventricular canal defect (AVCD), also called atrioventricular septal defect or endocardial cushion defect, is a congenital heart condition in which there is a hole in the centre of the heart and abnormal valves between the upper and lower chambers. In the complete form, there is a large hole involving both the atrial and ventricular septa and a single common valve instead of separate mitral and tricuspid valves. In the partial form, the defect is smaller and may mainly affect the atrial septum and mitral valve. Extra blood flows to the lungs, the heart has to work harder and can enlarge, and without repair, heart failure and high blood pressure in the lungs (pulmonary hypertension) can develop. AVCD is often associated with Down syndrome. Risk factors include family history of congenital heart disease, maternal diabetes, and certain infections or medications during pregnancy.

Symptoms, diagnosis and treatment

Symptoms may include fast or laboured breathing, poor feeding, failure to thrive, bluish skin (cyanosis), heart murmur, and recurrent chest infections. Diagnosis is made by echocardiography (including fetal echo in some pregnancies), ECG, and sometimes other tests. Surgery is usually recommended in the first year of life (often before 6 months) to close the holes and reconstruct the valves. Repair is done with open-heart surgery. After surgery, many children do well but need lifelong cardiology follow-up; some need further surgery on the valves later. We can refer you to a paediatric cardiac surgical centre for evaluation and care.

Recovery and follow-up

After AVCD repair, the child typically stays in hospital for several days to a couple of weeks. The team will monitor heart function, rhythm, and wound healing. At home, you will receive advice on feeding, activity, and when to seek help. Lifelong follow-up with a paediatric (and later adult) congenital heart specialist is standard to check the repaired valves and heart function; some children need further surgery or treatment for rhythm problems later. We can refer you to a paediatric cardiac surgical centre for evaluation and care.

Frequently asked questions

Is AVCD always linked to Down syndrome?
A significant proportion of children with AVCD have Down syndrome, but AVCD can occur in any child. Genetic counselling may be offered.
What is the outlook after AVCD repair?
Many children do well after repair. Some need further surgery on the valves or treatment for rhythm problems. Lifelong cardiology follow-up is standard.
When is surgery done?
Repair is typically planned in the first year of life, often before 6 months, to prevent heart failure and pulmonary hypertension.
What are the risks of AVCD surgery?
As with any open-heart surgery, there are risks of bleeding, infection, and rhythm problems. Your cardiac surgical team will explain how these are minimised and managed.