Pulmonary Atresia With Ventricular Septal Defect
Pulmonary atresia (PA) is a congenital heart defect in which the one-way valve (pulmonary valve) between the right ventricle (responsible for pumping oxygen-poor blood through the pulmonary artery and to the lungs) and pulmonary artery (responsible for carrying blood to the lungs) does not develop at all. In the case of pulmonary atresia with ventricle septal defect (PA with VSA), a hole between the two pumping chambers of the heart (ventricular septal defect) is also present. This combination of defects can also be classified as Tetralogy of Fallot.
About Pulmonary Atresia With Ventricular Septal Defect
Pulmonary atresia occurs when the pulmonary valve, which opens to allow blood to be pumped from the right ventricle to the lungs through the pulmonary artery, is not formed, blocking the flow of blood from traveling directly from the right ventricle to the lungs. Pulmonary atresia with ventricular septal defect occurs when a hole between the two pumping chambers of the heart (ventricular septal defect) is also present. The ventricular septal defect allows the right ventricle to grow and develop despite the pulmonary valve abnormality.
PA with VSD can present in many different ways and is sometimes associated with major aortapulmonary collateral arteries (MAPCAs). When native pulmonary circulation is underdeveloped, MAPCAs will arise (branch) from the aorta (the major blood vessel that takes blood from the heart to the rest of the body) to supply blood to the lungs.
Symptoms of Pulmonary Atresia With Ventricular Septal Defect
Symptoms of PA with VSD usually appear in the first few days of life.
Symptoms of PA with VSD may include:
- Fast breathing
- Poor feeding
- Poor weight gain
- Skin that appears pale or blue in color (cyanosis)
- Sleeping more than expected
- Sweating during feeding
Diagnosing Pulmonary Atresia With Ventricular Septal Defect
During physical examinations, your child’s doctor listens to your child’s heart and lungs and may detect a heart murmur, which are extra sounds heard throughout the cardiac cycle due to increased blood flow. If your pediatrician suspects increased blood flow, a recommendation to see a pediatric cardiologist may be made. Your doctor may also refer you to a pediatric cardiologist if your child is breathing fast, has poor exercise tolerance (for babies, this includes poor feeding), or has an enlarged liver.
Tests performed when diagnosing PA with VSD may include:
- Cardiac Catheterization: During cardiac catheterization, a small catheter (thin tube) is inserted into a larger blood vessel, typically in the groin, and guided to the heart where blood pressure and oxygen measurements can be taken in the aorta and pulmonary artery as well as the four chambers of the heart. A dye can also be injected through the tube to make both the heart’s structure and the MAPCAs more visible on an X-ray.
- Cardiac MRI or CT Scan: A cardiac MRI or CT scan is used to take more detailed images of the heart to help define the anatomy and detect anomalies, such as when there are MAPCAs.
- Chest X-Ray: A chest X-ray produces an image of the tissue and bones in the heart and lungs and helps your provider assess the shape, size, and structure of the heart and lungs as well as the aeration of or any congestion in the lungs.
- Echocardiogram: An echocardiogram uses ultrasound technology to create a moving image of the heart and its valves, allowing your provider to assess the structure and function of the heart. An echocardiogram also helps provide information about blood flow and how well the heart is pumping blood. An echocardiogram is not always the best way to observe MAPCAs.
- Electrocardiogram (ECG or EKG): An electrocardiogram uses electrodes that are placed on the body to record the electrical activity taking place in the heart. An ECG/EKG test helps detect abnormal rhythms, such as cardiac arrhythmias, stress on the heart, and damage to the heart muscles.
Treating Pulmonary Atresia With Ventricular Septal Defect
Treatment options for children with PA with VSA is tailored to their unique anatomy.
Treatment options for PA with VSA may include:
- Blalock-Thomas-Taussig Shunt: Children diagnosed with PA with VSD who do not have MAPCAs will usually undergo surgery as a newborn to ensure they have a reliable means of transporting blood to the lungs to receive oxygen. During this operation, a connection is made, which typically involves sewing a Gore-Tex tube between the right subclavian artery (the first artery that branched off the aorta) and the right pulmonary artery. Some of the blood traveling through the aorta toward the body will "shunt" through this connection and flow into the pulmonary artery to receive oxygen.
- Cardiac Catheterization: Using the same method as for diagnosis, a small tube can be inserted through a blood vessel in the groin and guided to the heart where a stent can be placed in the ductus arteriosus (a blood vessel that connects the aorta and pulmonary artery). When the child is around 6-12 months of age, they will undergo another operation in which the ventricular septal defect will be closed by placing a patch over the hole and a larger tube (conduit) will be sewn between the right ventricle and the pulmonary artery to provide a stable source of pulmonary blood flow. The tube does not grow and over time stops working properly, which results in the need to be replaced by performing an additional surgery. Once the child is adult-sized, they may be able to undergo procedures in the cardiac catheterization lab to help restore the function of the conduit.
Care Team Approach
The Texas Center for Pediatric and Congenital Heart Disease, a clinical partnership between Dell Children’s Medical Center and UT Health Austin, takes a multidisciplinary approach to your child’s care. This means your child and your family will benefit from the expertise of multiple specialists across a variety of disciplines. Your care team will include pediatric cardiologists, cardiothoracic surgeons, interventional cardiologists, critical care specialists, hospitalists, anesthesiologists, perfusionists, nurses, advanced practice providers, social workers, psychologists, child life specialists, dietitians, physical and occupational therapists, pharmacists, and more, who work together to provide unparalleled care for patients every step of the way. We collaborate with our colleagues at the Dell Medical School and The University of Texas at Austin to utilize the latest research, diagnostic, and treatment techniques, allowing us to identify new therapies to improve treatment outcomes. We are committed to communicating and coordinating your child’s care with referring physicians and other partners in the community to ensure that we are providing comprehensive, whole-person care.