First, don't blame yourself. Congenital heart defects (heart problems existing at birth) occur in about 1 out of every 125 live births. Family history and certain viral infections during pregnancy may indicate the cause. But in most cases, physicians don't know why the heart fails to develop properly.
Second, pain is not common. Many newborns with congenital heart defects have no symptoms. Some congenital heart defects can cause excessive sleepiness or rapid breathing. Others may cause babies to tire quickly while eating. Most likely, your child feels no different than other newborns.
Finally, there's a good chance your child's future will be bright. Most heart defects can be corrected or improved with surgery. Many children with congenital heart defects live full and healthy lives.
Your immediate challenge will be making sense of the information the doctor shares with you. Being able to picture the heart and understand how it works will help you navigate the road ahead.
The heart and how it works
Quite simply, the heart can be thought of as a sac divided into four chambers — two upper and two lower. The septum is the wall that separates the left and right sides. The two upper chambers are the right and left atrium (AY-tree-um). The two lower chambers are the right and left ventricles (VEN-trih-kuls).
The heart functions as a blood pump. It is made primarily of very strong muscle. This muscle squeezes (contracts) from 120 to 150 times a minute in infants. Try flexing your biceps this often in one minute and you'll get some idea of the demands placed on the heart. For the heart to keep blood moving in the right direction, valves act as one-way gates at the chamber openings.
To understand how the heart works, let's trace the path of blood through a normal heart. Blood from the body returns to the heart via veins to the right atrium. When the right atrium contracts, this blood moves through the tricuspid valve to the right ventricle. When this ventricle contracts, the blood moves through a large blood vessel, the pulmonary artery, to the lungs. It is in the lungs that blood picks up the oxygen we need to live. From the lungs, the next stop is the left atrium, and then through the mitral valve to the left ventricle. Finally, blood with its fresh supply of oxygen leaves the heart through another large blood vessel called the aorta. The aorta and its branches supply oxygen-rich blood to all parts of the body.
This simple roadmap of blood flow highlights several important points:
The normal flow of blood through the heart is one way Blood needs to move from the heart to the lungs and then back to the heart again Blood on the right side of the heart is oxygen-poor; on the left, oxygen-rich.
What can go wrong?
The heart forms in the first 8 weeks of fetal life. Defects can occur in the chambers, the valves or the blood vessels leaving the heart. These defects may result in:
A mixing of blood from the left side of the heart with blood from the right Blockage of blood flow Abnormal placement of the blood vessels leaving the heart A combination of these problems
In all, there are approximately 35 separate types of common congenital heart defects. Some defects require no treatment. Others may require urgent surgery. Let's look at several in more detail.
Holes in the heart
Several defects can be thought of as "holes" in the wall of the heart chambers or passageways between major blood vessels leaving the heart. These holes allow oxygen-rich and oxygen-poor blood to mix. If the holes are large and a lot of blood is mixed, the baby's skin may be a slight bluish color.
Ventricular septal defect is a hole in the wall between the right and left ventricles. Blood moves from the left ventricle to the right. This causes the right side of the heart to work harder, sends extra blood to the lungs and can increase blood pressure in the lungs. Small ventricular septal defects may close on their own without treatment. Larger defects may need surgical correction.
Atrial septal defect is an opening in the wall between the right and left atrium. The hole allows blood to move from the left atrium to the right. Similar to ventricular septal defects, the right side of the heart has the added burden of moving this extra blood to the lungs.
Patent ductus ateriosus overworks the heart and can lead to heart failure. Before birth, fetal lungs don't function. The ductus arteriosus (DUK-tus ahr-teer-ee-OH-sus) is an opening between the pulmonary artery and aorta that allows blood in the fetus to bypass the lungs. Once a newborn starts breathing oxygen, the opening needs to close. In most cases, this happens within a few hours of birth. If it does not, oxygen-rich blood intended for the body is directed back to the lungs. Surgery was once required for closing a patent ductus but today the baby can often be given medication that prompts the ductus to close.
Obstructed blood flow
When blood vessels or valves become obstructed, or narrowed, the heart must work harder to move the blood through them. Imagine trying to squeeze water out of a small hole in a balloon compared to a large hole and you'll get the idea. Three common obstructive defects are:
Pulmonary stenosis (steuh-NOE-sis) is a narrowing of the pulmonary valve, through which blood passes from the right ventricle to the pulmonary artery. This condition overworks the heart. The muscle of the right ventricle may thicken.
Aortic stenosis is a narrowing of the aortic valve, through which blood passes from the left ventricle to the aorta. This causes extra work for the left ventricle. The heart muscle thickens and the ventricle enlarges. Depending on the amount of narrowing, the child may have no symptoms, may tire easily or may have chest pain with vigorous physical activity.
Coarctation of the aorta is a constriction or narrowing of the aorta. It generally restricts blood flow to the lower part of the body. Sometimes the condition is not diagnosed until later in childhood or adulthood. It can cause high blood pressure in the upper part of the body.
Abnormal blood vessels
Several congenital heart defects involve incorrectly formed or positioned blood vessels going to and from the heart.
Transposition of the great vessels occurs when the pulmonary artery and aorta are on opposite sides of the heart from normal. The pulmonary artery leaves the left ventricle and the aorta leaves the right ventricle. This is a serious and immediately life-threatening defect. If the baby also has openings between the right and left sides of the heart — to ensure that some blood sent to the body carries oxygen — she or he may be able to survive long enough for corrective surgical treatment.
A combination of defects
Some congenital heart conditions are the result of not one but several defects.
Tetralogy of Fallot accounts for 10 percent of all congenital heart defects. In fact, this condition is a combination of four defects: a hole in the ventricular septum, a narrowed passage between the right ventricle and pulmonary artery, a shift in the connection of the aorta to the heart and thickened muscle in the right ventricle.
What is the outlook?
The impact of a congenital heart defect on your child's health will vary depending on the exact defect. Some defects may never cause problems. Some become a problem only later in life. Some cause major problems immediately or soon after birth.
After careful evaluation your doctor will discuss appropriate treatment options. In preparing for what lies ahead, stay informed and ask questions when you don't understand your doctor's advice. The chances of your newborn having a full and healthy life are promising.