Pulmonary atresia with intact ventricular septum

Also called PA/IVS, this rare congenital heart defect is diagnosed at or shortly after birth. Learn the symptoms and how it's treated.

Update Date: 15.04.2025

Overview
Symptoms
Causes
Risk factors
Diagnosis
Treatment
Overview
Symptoms
Causes
Risk factors
Diagnosis
Treatment

Overview

Pulmonary atresia (uh-TREE-zhuh) with intact ventricular septum, also called PA/IVS, is a rare heart condition that's present at birth. That means it's a congenital heart defect.

In this condition, the valve between the heart and lungs isn't fully formed. This valve is called the pulmonary valve. Blood can't flow from the right lower heart chamber, called the right ventricle, to the lungs.

A newborn baby relies on blood from a natural opening between the aorta and the lung artery. This opening is called the ductus arteriosus. It closes soon after birth. But it can be kept open with medicines.

Treatment for pulmonary atresia with intact ventricular septum may include medicines and one or more procedures or surgeries to fix the heart.

Symptoms

Symptoms of pulmonary atresia with intact ventricular septum, also called PA/IVS, may appear soon after birth. They can include:

  • Blue or gray skin. Changes may be harder or easier to see depending on the baby's skin color.
  • Fast breathing or shortness of breath.
  • Tiredness.
  • Poor feeding.

When to see a doctor

Pulmonary atresia with intact ventricular septum, also called PA/IVS, is often found during pregnancy or soon after birth. If your baby has symptoms of PA/IVS after you've left the hospital, call a healthcare professional right away.

Causes

The cause of pulmonary atresia with intact ventricular septum, also called PA/IVS, is not clear. Most congenital heart conditions happen during the first six weeks of pregnancy as a baby's heart is forming. The major blood vessels that run to and from the heart also begin to develop during this critical time. It's at this time that a congenital heart defect such as pulmonary atresia may begin to form.

Risk factors

What increases the risk of pulmonary atresia with intact ventricular septum, also called PA/IVS, is not well known. Possible risk factors for congenital heart defects such as PA/IVS may include:

  • Smoking. If you smoke, quit. Smoking during pregnancy or being around cigarette smoke increases the risk of some congenital heart conditions.
  • Alcohol use. Drinking alcohol during pregnancy may increase the risk of heart conditions in the baby.
  • Genetics. Changes in some genes have been linked to heart conditions at birth. For example, people with Down syndrome often are born with heart conditions.
  • Diabetes. Having type 1 or type 2 diabetes during pregnancy may change how a baby's heart forms. But diabetes that develops during pregnancy, called gestational diabetes, typically doesn't increase a baby's risk of congenital heart defects.
  • Rubella, also called German measles. Having rubella during pregnancy can cause changes in a baby's heart. A blood test can be done before pregnancy to see if you're immune to rubella. If you're not, you can get a vaccine.
  • Some medicines. Some medicines taken during pregnancy may increase the risk of congenital heart conditions. These include lithium (Lithobid) for bipolar disorder and isotretinoin (Claravis, Myorisan, others), which is used to treat acne. Talk with a healthcare professional about the medicines you take.

Diagnosis

Pulmonary atresia with intact ventricular septum, also called PA/IVS, can be diagnosed before birth with an ultrasound during a routine pregnancy screening. Or it may be diagnosed soon after the baby is born.

Tests

Tests used to diagnose pulmonary atresia with intact ventricular septum, also called PA/IVS, include:

  • Pulse oximetry. A small sensor clipped to a hand or foot measures how much oxygen is in the blood.
  • Electrocardiogram. Also called an ECG or EKG, this simple test measures the electrical activity of the heart. It shows how the heart is beating. Sticky patches with sensors, called electrodes, attach to the chest and sometimes to the arms or legs. The sensors connect to a monitor, which prints or displays results.
  • Chest X-ray. A chest X-ray shows the shape and size of the heart and lungs.
  • Echocardiogram. Sound waves are used to make pictures of the beating heart. An echocardiogram shows how blood moves through the heart and heart valves, including the pulmonary valve. An echocardiogram done during pregnancy is called a fetal echocardiogram. It can be used to diagnose pulmonary atresia in the baby.
  • Cardiac catheterization. This test shows the heart's arteries. A doctor places a thin, flexible tube called a catheter into a blood vessel, usually in the groin. It's guided to the heart. Dye flows through the catheter and into the heart arteries. The dye helps the arteries show up more clearly on X-rays.

Treatment

Babies with pulmonary atresia need treatment right away. It's best to get treatment at a medical center with surgeons and other healthcare professionals who have experience with complex heart conditions present at birth.

Treatment for pulmonary atresia with intact ventricular septum, also called PA/IVS, may include medicines and one or more procedures or surgeries.

Medications

Medicine may be given through an IV to keep the ductus arteriosus open. This is not a permanent treatment for pulmonary atresia. But it keeps the baby stable until a surgery or procedure can be done to permanently fix blood flow.

Surgeries or other procedures

A baby with pulmonary atresia with intact ventricular septum needs one or more surgeries or procedures to improve blood flow and fix the heart.

Some of these treatments are done in the first days to weeks of a baby's life. Others are done later. The type of surgery or procedure depends on many things. These include the size of the right lower heart chamber and heart valves and whether the baby has other heart conditions.

Treatments in the first days to weeks of life

  • Balloon valvotomy. This treatment helps open the pulmonary valve. The doctor inserts a long, thin tube called a catheter into a blood vessel in the baby's groin and guides it to the heart. A balloon on the tip of the catheter is inflated to widen the valve opening. The balloon is deflated, and the catheter and balloon are removed.
  • Stenting. The doctor places a rigid tube called a stent in the natural opening between the aorta and pulmonary artery. This opening is called the ductus arteriosus. It usually closes soon after birth. Keeping it open lets blood go to the lungs.
  • Shunting. This surgery uses a tube to create a new path for blood to flow to the pulmonary arteries. The tube is called a shunt. An example of this treatment is the Blalock-Taussig shunt procedure or RV-PA shunt. Once this is done, medicine is not needed to keep the ductus arteriosus open. Babies eventually outgrow this shunt.

Surgeries done later

  • Glenn operation. This surgery most often is done between 4 and 6 months of age. The surgeon connects a large vein, called the superior vena cava, to the pulmonary artery. Another large vein keeps blood flowing to the right side of the heart. If this surgery is done without using a heart-lung machine, it's called an off-pump Glenn procedure.
  • 1.5 ventricle repair. This surgery may be done in babies with PA/IVS who have a relatively well-formed lower right heart chamber. A surgeon creates a pathway from the lower right heart chamber to the pulmonary artery. The Glenn procedure also is done. The term "1.5 ventricle" means that the lower right heart chamber is doing some but not all of the heart's work.
  • Fontan procedure. If the lower right lower heart chamber stays too small to do its work, surgeons may make a new path for blood to flow. The pathway lets most, if not all, of the blood coming to the heart to go into the pulmonary artery. The Fontan procedure is most often done when a child is 3 or 4 years old.
  • Hybrid procedures. These are surgical and catheter treatments that are done at the same time. They're sometimes done without a heart-lung machine.

After treatment, babies with pulmonary atresia with intact ventricular septum, also called PA/IVS, should have regular health checkups with a heart doctor trained to treat children. This type of healthcare professional is called a pediatric cardiologist. Due to advances in treatment and technology, many people with PA/IVS live into adulthood. Adults with the condition should be followed by a doctor with training in adult congenital heart diseases.

© 2025 Mayo Foundation for Medical Education and Research. All rights reserved. Terms of Use