Congenital diseases are those disorders which a person is born with. Congenital diseases can affect all parts of the body; congenital lung problems, skin problems, and brain problems all exist. One particular category of note is that of congenital heart disease. Most of the time, we don’t know what causes these illnesses, although they can often be treated with medication or corrective surgery.
In this article, we’ll look at 5 of the more well-known congenital heart diseases: Kawasaki Disease, Marfan syndrome, pulmonary atresia, single ventricle, and tricuspid atresia.
1. Kawasaki Disease
Kawasaki Disease (also known as “mucocutaneous lymph node syndrome”) is a rare illness that involves the mouth, skin, nose, throat and lymph nodes. It’s a congenital disease, and cannot be eliminated. It has many well-known symptoms, which are structured into phases. In the first phase, a fever appears and lasts from somewhere around 5 days to 2 weeks. There are other symptoms during the phase, too: cracked lips, swollen tongue, severely red eyes, sore throat, swollen, purple-red palms, and swollen lymph nodes, among others. In the second and final phase, the skin on the hands starts peeling off in large sections, sometimes even when the patient has already been treated. Other symptoms include joint pain, vomiting, pain in the abdomen, and diarrhea. If these symptoms appear in a person, it is absolutely necessary that the patient is brought to the doctor right away.
Most people who have Kawasaki Disease are children under five years old. If Kawasaki Disease is treated in time, patients generally don’t suffer from long-term problems. However, if it is not treated, it can cause serious complications, like vasculitis, which is the inflammation of the blood vessels. The medium-sized arteries, as well as the parts of the heart—its muscle, valves, linings, and outer layer—can also become inflamed. Abnormal functioning of the heart valves or arrhythmias (heart rate changes) may also be present. The disease can even harm the coronary arteries (which are the ones that carry blood to the heart).
So far, no one knows what causes Kawasaki Disease, which is more prevalent in late winter and early spring. Although it can affect anyone, it affects people of Korean and Japanese ancestry most often.
2. Marfan syndrome
Marfan syndrome is a congenital heart disorder. A person cannot develop Marfan; they must be born with it. It is caused by a mutation in the gene that signals to the body how to make the gene fibrillin-1. Through the mutation, a protein—transforming growth factor beta, or TGF-β—is produced in larger amounts than usual. This surplus of TGF-β causes many medical problems.
Marfan syndrome affects the connective tissues of the body, which a) hold the body, its cells, its tissues, and its organs together, and b) contributes to the growth and development of the body. Connective tissue can be found all over the body, so many parts of the body can be affected by Marfan syndrome. These include, for example, the joints, bones, eyes, heart, and blood vessels.
Marfan syndrome can be identified because people who have it are usually tall and thin, with arms, legs, fingers, and toes that are disproportionately long. Other traits of the disorder can affect the heart, bones, blood vessels, and joints. Marfan traits can also get worse over time.
Marfan syndrome is not always life-threatening. However, some traits of the disorder—for example, aortic enlargement (in which the aorta is larger than usual)—can be fatal. It is vital that people who have it get diagnosed and treated early so that they don’t suffer from life-threatening complications. The outcomes of some treatments are more effective if they’re started earlier. Moreover, it is crucial for people to get monitored regularly. Medications for Marfan include those that keep blood pressure low, since they tend to lessen the stress on the aorta. Sometimes, people need to get preventive surgery to reverse the damage on their aortas.
The incidence of Marfan syndrome is about 1 person for every 5,000 people. It affects both men and women, of different ethnic groups. About 75% of the people who have Marfan syndrome inherit it from one of their parents. This is because that parent carries the genetic mutation that causes Marfan in their DNA. Someone who has Marfan syndrome has a 50% chance of passing it on when they have children. However, the remainder of people get it because they’ve developed a spontaneous mutation. Experts estimate that half of the people who have Marfan syndrome aren’t aware of it.
3. Pulmonary atresia
For people who have pulmonary atresia, their pulmonary valve is not properly formed. Located on the heart’s right side, this valve regulates blood flow from the right ventricle into the lungs. Where the valve opening would normally be, patients with this disorder instead have a solid sheet of tissue, and the valve remains closed. This can be very serious, and babies often need surgery soon after birth to deal with this problem.
The consequences of pulmonary atresia are that blood on the right side of the heart can’t travel to the lungs, where it’s supposed to gather oxygen. Because blood can’t flow from the right ventricle into the pulmonary artery, it tends to use other routes to get on its path. One such route is the foramen ovale, which is an opening between the right and left upper chambers of the heart that opens up during pregnancy.
The causes of pulmonary atresia are not known. Sometimes, it may be caused by gene or chromosomal changes. According to one theory, heart defects are caused by a combination of gene and environmental factors. Research has shown that 1 out of every 10,000 children is born with this disorder.
Pulmonary atresia is associated with the patent ductus arteriosus, another kind of heart defect. It also often occurs in conjunction with a ventricular septal defect (VSD). If a patient has a VSD and pulmonary atresia, then their condition is referred to as “pulmonary atresia with VSD.” If they do not, instead, they have “pulmonary atresia with intact ventricular septum” (PA/IVS).
In the case of PA/IVS, the wall between the ventricles remains intact. The right ventricle is underdeveloped because of the lack of blood flow. This can make it difficult for the heart to pump blood throughout the body. Because the pulmonary valve doesn’t form, the main pulmonary artery—which carries blood out of the right ventricle—is quite small.
In the cast of pulmonary atresia with VSD, the VSD allows blood to flow into the right ventricle. As such, the ventricle can develop more in these patients than in PA/IVS patients. This form of the disorder is similar to tetralogy of Fallot, a congenital heart defect that is responsible for low levels of oxygen inside a person’s blood.
4. Single ventricle
Normally, hearts have two ventricles. However, in patients with single ventricle (also called a “univentricular heart”), they will either have a single ventricle or two of them, one of which has not developed properly. (Technically, “single ventricle” is a misnomer.) Single-ventricle heart defects are very common congenital heart problems. They are associated with a number of heart problems, such as mitral valve atresia, double-inlet ventricle, hypoplastic left-heart and right-heart syndromes, and PA/IVS.
Patients with single ventricle have two normal atria, which open up into the ventricle through the atrioventricular valve. Some patients also have double-inlet ventricle, a condition in which two atrioventricular valves open up into the ventricle. Either way, the single ventricle connects the aorta and pulmonary artery, which might have their positions reversed. One significant problem associated with single ventricle patients is that unoxygenated and oxygenated blood mix together in their one ventricle before flowing into the aorta and pulmonary artery.
Treatment consists of different surgeries, depending on which medical problem the patient’s single ventricle is attached to. Examples of surgeries include the Fontan operation (in which a connection is created between the right atrium and pulmonary artery) and the Blalock-Taussig shunt (in which a small tube is used to reroute blood flow).
5. Tricuspid atresia
Patients with tricuspid atresia are lacking a tricuspid valve, which is on the right side of the heart. The result of this is that blood cannot flow from the right atrium to the right ventricle. In consequence, the right ventricle is of small size and is poorly developed.
Patients are able to survive when there is an opening in the wall between the two atria (also known as an “atrial septal defect”) and an opening in the wall between the two ventricles (a VSD). This is because the venous blood returning to the right atrium runs inside the atrial septal defect and through the left atrium. From there, it combines with the oxygenated blood that’s found in the lungs.
Treatment involves a shunting procedure which increases blood flow to the lungs. In some cases, when patients have too much blood moving into their lungs, they require pulmonary artery banding in order to decrease this blood flow. In other cases, a Fontan procedure is a viable option.