Atrial septal defect (ASD)

概述

An atrial septal defect (ASD) is a hole in the wall (septum) between the two upper chambers of your heart (atria). The condition is present at birth (congenital).

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

The hole increases the amount of blood that flows through the lungs. A large, long-standing atrial septal defect can damage your heart and lungs. Surgery or device closure might be necessary to repair atrial septal defects to prevent complications.

症状

Many babies born with atrial septal defects have no signs or symptoms. Signs or symptoms can begin in adulthood.

Atrial septal defect signs and symptoms can include:

• Shortness of breath, especially when exercising
• Fatigue
• Swelling of legs, feet or abdomen
• Heart palpitations or skipped beats
• Stroke
• Heart murmur, a whooshing sound that can be heard through a stethoscope

When to see a doctor

Contact your doctor if you or your child has:

• Shortness of breath
• Easy tiring, especially after activity
• Swelling of legs, feet or abdomen
• Heart palpitations or skipped beats

病因

How the heart normally 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. In the lungs, blood picks up oxygen then returns it to the heart's left side. The left side of the heart then pumps the blood through the aorta and out to the rest of the body.

Why do heart defects develop?

Doctors know that heart defects present at birth (congenital) arise from errors early in the heart's development, but there's often no clear cause. Genetics and environmental factors might play a role.

How the heart works with an atrial septal defect

A large atrial septal defect can cause extra blood to overfill the lungs and overwork the right side of the heart. If not treated, the right side of the heart eventually enlarges and weakens. The blood pressure in your lungs can also increase, leading to pulmonary hypertension.

There are several types of atrial septal defects, including:

• Secundum. This is the most common type of ASD and occurs in the middle of the wall between the atria (atrial septum).
• Primum. This defect occurs in the lower part of the atrial septum and might occur with other congenital heart problems.
• Sinus venosus. This rare defect usually occurs in the upper part of the atrial septum and is often associated with other congenital heart problems.
• Coronary sinus. In this rare defect, part of the wall between the coronary sinus — which is part of the vein system of the heart — and the left atrium is missing.

风险因素

It's not known why atrial septal defects occur, but some congenital heart defects appear to run in families and sometimes occur with other genetic problems, such as Down syndrome. If you have a heart defect, or you have a child with a heart defect, a genetic counselor can estimate the odds that future children will have one.

Some conditions that you have during pregnancy can increase your risk of having a baby with a heart defect, including:

• Rubella infection. Becoming infected with rubella (German measles) during the first few months of your pregnancy can increase the risk of fetal heart defects.
• Drug, tobacco or alcohol use, or exposure to certain substances. Use of certain medications, tobacco, alcohol or drugs, such as cocaine, during pregnancy can harm the developing fetus.
• Diabetes or lupus. Having diabetes or lupus might increase your risk of having a baby with a heart defect.

并发症

A small atrial septal defect might never cause any problems. Small atrial septal defects often close during infancy.

Larger defects can cause serious problems, including:

• Right-sided heart failure
• Heart rhythm abnormalities (arrhythmias)
• Increased risk of a stroke
• Shortened life span

Less common serious complications may include:

• Pulmonary hypertension. If a large atrial septal defect goes untreated, increased blood flow to your lungs increases the blood pressure in the lung arteries (pulmonary hypertension).
• Eisenmenger syndrome. Pulmonary hypertension can cause permanent lung damage. This complication, called Eisenmenger syndrome, usually develops over many years and occurs uncommonly in people with large atrial septal defects.

Treatment can prevent or help manage many of these complications.

Atrial septal defect and pregnancy

Most women with an atrial septal defect can go through pregnancy without problems related to the defect. However, having a larger defect or having complications such as heart failure, arrhythmias or pulmonary hypertension can increase the risk of complications during pregnancy.

Doctors strongly advise women with Eisenmenger syndrome not to become pregnant because it can endanger their lives.

The risk of congenital heart disease is higher for children of parents with congenital heart disease. Anyone with a congenital heart defect, repaired or not, who is considering starting a family should talk to a doctor. The doctor might recommend repair before pregnancy.

预防

In most cases, atrial septal defects can't be prevented. If you're planning to become pregnant, schedule a visit with your health care provider. This visit should include:

• Getting tested for immunity to rubella. If you're not immune, ask your doctor about getting vaccinated.
• Going over your current health conditions and medications. You'll need to monitor certain health problems during pregnancy. Your doctor might also recommend adjusting or stopping certain medications before you become pregnant.
• Reviewing your family medical history. If you have a family history of heart defects or other genetic disorders, consider talking with a genetic counselor to determine what the risk might be.