An atrial septal defect (ASD) is a hole in the heart between the upper chambers (atria). The hole increases the amount of blood that flows through the lungs. The condition is present at birth (congenital heart defect).

Small atrial septal defects might be found by chance and never cause a concern. Others close during infancy or early childhood.

A large, long-term atrial septal defect can damage the heart and lungs. Surgery may be needed to repair an atrial septal defect and to prevent complications.


Types of atrial septal defects include:

  • Secundum. This is the most common type of ASD. It occurs in the middle of the wall between the upper heart chambers (atrial septum).
  • Primum. This type of ASD affects the lower part of the atrial septum and might occur with other congenital heart defects.
  • Sinus venosus. This rare type of ASD usually occurs in the upper part of the wall separating the heart chambers. It’s also associated with other heart structure changes present at birth.
  • Coronary sinus. In this rare type of ASD, part of the wall between the coronary sinus — which is part of the vein system of the heart — and the left upper heart chamber (left atrium) is missing.


To understand the causes of congenital heart defects, it may be helpful to know how the heart typically works.

The heart is divided into four chambers, two on the right and two on the left. To pump blood throughout the body, the heart uses its left and right sides for different tasks.

The right side of the heart moves blood to the lungs through the lung (pulmonary) arteries. In the lungs, blood picks up oxygen then returns to the heart’s left side through the pulmonary veins. The left side of the heart then pumps the blood through the body’s main artery (aorta) and out to the rest of the body.


Because the exact cause of most congenital heart defects is unknown, it may not be possible to prevent these conditions. If you have a high risk of giving birth to a child with a congenital heart defect, genetic testing and screening may be done during pregnancy.

There are some steps you can take to help reduce your child’s overall risk of birth defects such as:

  • Get proper prenatal care. Regular checkups with a health care provider during pregnancy can help keep mom and baby healthy.
  • Take a multivitamin with folic acid. Taking 400 micrograms of folic acid daily has been shown to reduce birth defects in the brain and spinal cord. It may help reduce the risk of heart defects as well.
  • Don’t drink or smoke. These lifestyle habits can harm a baby’s health. Also avoid secondhand smoke.
  • Get a rubella (German measles) vaccine. A rubella infection during pregnancy may affect a baby’s heart development. Get vaccinated before trying to get pregnant.
  • Control blood sugar. If you have diabetes, good control of your blood sugar can reduce the risk of congenital heart defects.
  • Manage chronic health conditions. If you have other health conditions, including phenylketonuria, talk to your health care provider about the best way to treat and manage them.
  • Avoid harmful substances. During pregnancy, have someone else do any painting and cleaning with strong-smelling products.
  • Check with your provider before taking any medications. Some medications can cause birth defects. Tell your provider about all the medications you take, including those bought without a prescription.

Consult a cardiologist in India

Cost of Congenital heart defects – ASD/VSD Closure surgery in India.