Atrial septal defect (patient information)

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Overview
Atrial septal defect or ASD is type of congenital heart defect in which the wall separating the upper chambers of the heart does not fuse completely. During fetal development, the opening between the two atria (the upper chambers of the heart) is needed to allow blood to bypass the lungs. Eventually, as the fetus becomes more developed, the lungs can support circulation and the opening fuses shut. An ASD can result in shunting of blood disproportionately between the right and left sides of the heart.

What are the symptoms of Atrial septal defect?

 * When the person has no other congenital defect, symptoms may be absent, particularly in children.
 * Symptoms may begin any time after birth through childhood and even into adulthood.
 * Symptoms may include:
 * Difficulty breathing
 * Heart palpitations in adults
 * Frequent respiratory infections in children
 * Shortness of breath with activity


 * Other health problems may also cause these symptoms. Only a doctor can tell for sure. A person with any of these symptoms should tell the doctor so that the problems can be diagnosed and treated as early as possible.

What causes Atrial septal defect?

 * A heart normally develops with a small opening between the two upper chambers of the heart (called atria) to allow blood to bypass the lungs. As the lungs become more developed, the heart no longer needs to bypass the blood and the opening between atria will close.
 * An atrial septal defect occurs when the opening between the two chambers does not close completely
 * In rare cases, the hole may spontaneously close after birth.
 * Shunting refers to when the blood flows from the left chamber to the right chamber.
 * If too much blood moves from the right side of the heart, pressures in the lungs build up. The shunt can be reversed so that blood flows from right to left.



Who is at highest risk?

 * Worldwide, atrial septal defects occur in 1 in 1500 live births.
 * The Centers for Disease Control (CDC) estimated that, every year, 1,966 babies in the United States are born with an atrial septal defect.
 * As with most congenital heart diseases, it is unclear exactly why certain babies are born with atrial septal defects.
 * More commonly found in women than men, the female-to-male ratio of 2:1.
 * More common in families with a history of genetic problems and other congenital heart diseases.
 * Certain types of atrial septal defects are associated to Down syndrome.
 * Genetic counseling may be performed to estimate the likelihood that any future children may be born with an atrial septal defect.


 * Expectant mothers exposed to rubella may have an increased risk in having a baby with a heart defect.
 * Drug and alcohol use during pregnancy can harm fetal development. Alcohol use during pregnancy nearly doubles the likelihood of an atrial septal defecft.

When to seek urgent medical care?

 * Call your health care provider if your baby has the following symptoms as soon as possible:
 * Heart failure
 * Shortness of breath (Dyspnea)
 * Blueish coloring to the skin
 * Failure to thrive


 * Call your health care provider if you are an adult experiencing the following symptoms:
 * Heart failure
 * Shortness of breath (Dyspnea)
 * Blueish coloring to the skin
 * Pounding or racing of the heart

Diagnosis

 * Listening to heart sounds (Auscultation): Using a stethoscope, a doctor can listen to the beating of the heart. A doctor may hear abnormal heart sounds called a murmur. If the defect is large enough, the increase in blood flow across the heart valves  may create a secondary murmur between beats.
 * Echocardiography: This kind of non-invasive, painless sonar test can help the doctor closely examine an atrial septal defect. It uses sound waves to produce an image of the ventricles, atrium and great vessels. An echocardiogram can determine if blood is flowing properly from the right to the left systems. Furthermore, the doctor can measure the speed of blood flow through patient's heart and the pulmonary blood pressure using the echocardiogram.  This is important to determine if there is excess flow through the lungs and if there is damage to the vessels in the lung.
 * Chest x-ray: An x-ray image of chest allows the doctor to check the size and shape of your heart. A chest x ray also helps the doctor check the condition of your lungs. Patients with an atrial septal defect may show enlarged right atrial border on an x -ray.
 * Chest CT or MRI: A chest CT or MRI can demonstrate the details of the heart extremely well, such as the positions of valvular, vascular, atrial and ventricular structures and their relationships to one another.
 * Electrocardiogram (ECG): Electrocardiogram determine if there are abnormal electric activities of the heart as a result of an ASD. The ECG can provide information about the heart rhythm and the size of the heart chambers.

Treatment options
The classification of the atrial septal defect must be assessed. Potential tests include:
 * MRI
 * Chest x-ray
 * Echocardiogram

If the atrial septal defect is determined to be an ostium secundum defect, patients have the option of percutaneous transcatheter closure or surgical closure. Percutaneous closure is minimally invasive, traveling through the femoral artery up to the heart. It involves the usage of a guide wire catheter to close the septal hole. Surgical closure is more invasive and involves the usage of sutures to close the septal hole. The purpose of both procedures is to close the septal hole and restore normal circulation from the right to left sides of the heart. If the atrial septal defect is determined to be any other type, the only option is surgical closure. This invasive procedure varies in execution depending on the gender and age of the patient, as certain incisions are more appropriate for specific genders and specific age groups. Recovery time is difficult to generalize and depends largely on the type of incision, the age of the patient, and the severity of symptoms.

Prophylactic (preventive) antibiotics should be given prior to dental procedures to reduce the risk of developing infective endocarditis immediately after surgery for the ASD, but they are not required later on.

Where to find medical care for an atrial septal defect?
Directions to hospitals treating atrial septal defects

What to expect (Outlook/Prognosis)?
Small atrial septal defects often cause very few problems and may be found much later in life. Many problems can occur if the shunt is large, however. In advanced and severe cases with large shunts the increased pressure on the right side of the heart would result in reversal of blood flow (now from right to left). This usually results in significant shortness of breath. With a small to moderate atrial septal defect, a person may live a normal life span without symptoms. Larger defects may cause disability by middle age because of increased blood flow and shunting of blood back into the pulmonary circulation. Some patients with ASD may have other congenital heart conditions, such as a leaky valve.

Possible complications
Individuals with ASD are at an increased risk for developing a number of complications including:
 * Rapid heart rate (in adults)
 * Heart failure
 * Pulmonary overcirculation
 * Hypertension in the lungs
 * Stroke

Prevention
There is no known way to prevent the defect, but some of the complications can be prevented with early detection.

An ASD patient's perspective
Disclaimer: It is the aim of WikiDoc to connect patients with real, tangible information as they learn more about the conditions that affect their lives directly. The following is a brief, informational video produced by the Detroit Medical Center educational video series. All views in the video are of the patient, family, and physicians of Detroit Medical Center. No credit is taken by WikiDoc for the material within this video. This video is intended for educational purposes only and not to substitute the consultation of a licensed medical expert.

