ATRIOVENTRICULAR SEPTAL DEFECT – Atrioventricular septal defect (AVSD) is a type of congenital heart defect (a heart defect that is present at birth) in which there is a hole in the wall (septum) between the left and right chambers of the heart. This hole occurs at the point where the upper and lower chambers of the heart meet and can cause a number of complications.
AVSDs are classified by how serious the defect is. In the partial form of the condition, blood is allowed to travel between the left and right sides of the heart. In the complete form of the condition, blood can travel freely through all four chambers of the heart.
Children with an AVSD will usually begin to show symptoms within six to eight weeks of birth, if not immediately. These symptoms are similar to the symptoms of heart failure as the heart struggles to supply the body with oxygenated blood. Other complications include an enlarged heart and high blood pressure in the lungs (pulmonary hypertension). Heart failure may also result.
Surgery is always necessary to treat an AVSD. Unlike many other heart defects present at birth, an AVSD will not spontaneously correct itself. If the corrective surgery cannot be performed immediately, then another surgery can be performed in the meantime to improve the child’s condition until the surgery can be done.
COARCTATION OF THE AORTA – Coarctation of the aorta is a condition in which the walls of the aorta become pinched, narrowed or pressed together, constricting blood flow through the blood vessel. The narrowing may be in a specific location, or run along an entire section of the aorta.
Coarctation is a potentially dangerous condition because the aorta is the main artery that carries oxygen-rich blood from the heart to the rest of the body. It travels from the heart, through the chest and down into the abdomen. Smaller arteries branch from its length, sending oxygen-rich blood to the brain, head, arms, legs and torso.
When any part of this vital artery is narrowed, it can lead to fatal consequences. In fact, patients who do not undergo surgery for this condition are unlikely to reach the age of 40.
Coarctation of the aorta can be treated with surgery or with less-invasive catheter-based methods. If corrected before 10 years of age, the majority of patients are successfully treated, although there is some risk that the aorta may once again narrow later in life. After treatment, patients will likely need to take antibiotics before any dental, medical or surgical procedure that they may have from that point on to reduce their risk of infection in either the aorta or one of the heart’s four valves (endocarditis).
DILATED CARDIOMYOPATHY – A dilated cardiomyopathy (DCM) occurs when the heart muscle is enlarged and weakened and cannot pump adequate oxygen-rich blood to the body. A number of conditions may cause dilated cardiomyopathy, including:
- Coronary artery disease
- Idiopathic (unknown cause)
- Viral infections
- Genetic factors
Dilated cardiomyopathy is the most common cause of heart failure. It derives its name for the following reasons:
- Dilated refers to the dilation or enlargement of one or both lower chambers of the heart (ventricles). It frequently begins in the heart’s main pumping chamber, the left ventricle. This chamber is responsible for pumping oxygen-rich blood from the heart to the rest of the body. Its weakened condition often leads to heart failure.
- Cardiomyopathy is a disease in which the heart is abnormally enlarged, thickened, and/or stiffened. As a result, the heart cannot pump blood as well as it should.
Treatment for dilated cardiomyopathy often begins by attempting to treat the underlying condition. If it is caused by coronary artery disease, for example, the physician may first attempt to treat coronary artery disease. However, a significant number of dilated cardiomyopathies have no known cause, so physicians must attempt to alleviate symptoms and stop the progressive degeneration of the heart. This approach might include strategies to strengthen the heart, decrease the work of the heart, allow the heart to shrink in size, lower blood pressure (if necessary) and control any abnormal heart rhythms (arrhythmias) that may be present. A pacemaker or implantable cardioverter defibrillator (ICD) may be surgically inserted to control arrhythmias that do not respond to medication. As a last resort, a heart transplantation may be considered. Other techniques to treat this condition are currently being developed.
According to the American Heart Association, dilated cardiomyopathy is the most common form of cardiomyopathy, accounting for 87 percent of all diagnosed cases, and the most common reason for heart transplantation. The five-year survival rate for dilated cardiomyopathy is 50 percent and 10-year rate is 25 percent.
DOUBLE OUTLET RIGHT VENTRICLE – Double outlet right ventricle (DORV) is a very rare heart defect in which both of the great vessels of the heart are connected to the right ventricle when they should be connected to separate ventricles. The degree of the defect can vary. As a result of this defect, the left ventricle cannot pump blood to the aorta and out to the rest of the body.
Fortunately, DORV patients also have a ventricular septal defect (VSD), which is a hole in the wall (septum) between the left and right ventricles. This hole allows oxygen-rich blood to pass from the left ventricle to the right, where it is pumped into the aorta and to the rest of the body. Therefore, circulation of oxygen-rich blood is accomplished, but only at great stress to the system. Without a VSD, circulation could not be accomplished at all.
Surgery, which is necessary to repair DORV, is usually complicated by the presence of additional heart defects.
EBSTEIN’S ANOMALY – Ebstein’s anomaly is a rare heart defect that involves a deformed and misplaced tricuspid valve and usually occurs along with other heart defects. In a normal heart, the tricuspid valve is located between the right atrium and the right ventricle. It opens and closes at precise intervals, allowing blood to travel from the right atrium to the right ventricle, which then pumps the blood to the lungs to pick up oxygen.
In Ebstein’s anomaly, however, the tricuspid valve droops into the right ventricle and cannot close properly. This leaky valve allows oxygen-poor blood to flow backward into the right atrium, instead of flowing into the right ventricle to be pumped to the lungs (tricuspid regurgitation).
As a result, less blood receives fresh oxygen, which leads to cyanosis – a bluish tint to the skin because the body is not receiving enough oxygen-rich blood (a condition often called blue baby in infants).
In addition to the leaky tricuspid valve, patients with Ebstein’s anomaly also tend to have associated heart defects, including a patent foramen ovale or an atrial septal defect (ASD). The ASD is the more serious of the two. An ASD is a hole between the left and right atria that allows oxygen-poor blood from the right atrium to mix with oxygen-rich blood in the left atrium. These two types of blood should always remain separated.
The range of problems associated with Ebstein’s anomaly depends on the severity of the condition. Severe Ebstein’s anomaly is a life-threatening condition that can progress to heart failure or death and must be treated immediately. A person with mild Ebstein’s anomaly might show no symptoms until adulthood, and then only show mild symptoms.
Treatment for Ebstein’s anomaly depends on the severity of the symptoms. Mild Ebstein’s may be treated with medication to relieve symptoms. More serious Ebstein’s will usually require open-heart surgery, usually early in life. After surgery, lifelong medical follow-up and close medical management will be necessary. For example, patients will need to take antibiotics before any dental, medical or surgical procedure to prevent a potentially life-threatening infection called endocarditis.
ENDOCARDITIS – Endocarditis a relatively uncommon but potentially dangerous inflammation, usually caused by infection in vulnerable areas of the endocardium – the innermost layer of the heart’s chambers and valves.
In the vast majority of patients, endocarditis can be effectively treated with medication and/or surgery. Nevertheless, endocarditis can cause serious damage or even death. Because of the dangerous nature of this condition, people at moderate and high risk for endocarditis (e.g., any type of valvular heart disease) are strongly advised to take antibiotics both before and immediately after any dental or medical procedure. This preventative action can help to kill any bacteria that enter the bloodstream as a result of the procedure, minimizing the risk of developing endocarditis.
HYPOPLASTIC LEFT HEART SYNDROME – Hypoplastic left heart syndrome (HLHS) is a very serious disease present at birth (congenital heart disease) in which the chambers, valves and related blood vessels on the left side of the heart are so malformed that they cannot efficiently pump blood to the rest of the body. This condition is also frequently referred to as left heart hypoplasia by physicians.
Before treatment options became available in the 1990s, HLHS babies could not survive longer than a few weeks. Today, there are open-heart surgeries that offer new hope for a longer life, though researchers do not yet know if surgery allows HLHS patients to mature past childhood. The open heart surgeries currently available are heart transplant surgery and the Norwood procedure (a series of surgeries, each done at a different age, ranging from infancy through the toddler years). Both heart transplantation and the Norwood procedure carry risks and should only be done by a fully qualified pediatric heart surgeon.
KAWASAKI DISEASE – First identified in Japan in 1967, Kawasaki disease is a type of disease that primarily affects young children and is believed to be caused by a noncontagious infection. Kawasaki disease is characterized by fever, rash, swelling in the hands, feet and lymph nodes, and other symptoms. The condition may also affect the linings of blood vessels and the heart muscle, and can lead to aneurysms and heart attack. For example, damage to the coronary arteries could increase the risk of heart attack in adulthood.
Fortunately, treatment can dramatically reduce the likelihood of cardiovascular damage from the disease. The condition tends to resolve on its own in a month or two, and death from the condition is rare. Surgery or catheter-based procedure is also available to treat any long-term effects of the disease.
LEFT VENTRICULAR HYPERTROPHY – Left ventricular hypertrophy (LVH) is a condition in which the heart’s lower left-chamber (left ventricle) has grown abnormally thick. This may happen in response to an underlying condition that causes an abnormal strain on the heart’s main pumping chamber. Most commonly, the underlying condition is high blood pressure, and the resulting LVH can often be controlled or even improved with blood pressure medication (antihypertensives). Other underlying conditions include valvular heart disease and coronary heart disease.
Whichever underlying condition is present, the focus is on the underlying disease process to prevent or even reverse the thickening and/or enlargement of the left ventricle. Treatment is important because LVH increases the risk of heart failure and sudden cardiac death. The best strategies for preventing LVH are to control blood pressure, weight and blood sugar (diabetes). LVH usually produces no symptoms.
Note that “enlarged heart” is a broad term used to describe enlargement seen on a chest x-ray. LVH refers strictly to the thickening of the heart muscle, and it may or may not be associated with enlargement. For example, LVH caused by high blood pressure most often has no associated enlargement (dilation) on x-ray.
LONG QT SYNDROME – Long QT syndrome (LQTS) is a rare, usually inherited and sometimes fatal disorder of the heart’s electrical system. LQTS patients often do not notice any symptoms until they are under some kind of physical or emotional stress. At that point, they could experience fainting (syncope) or more dangerous heart conditions such as ventricular tachycardia (a very fast, irregular heartbeat). In the most severe cases, LQTS patients may suffer sudden cardiac death. Women are more prone to sudden cardiac death as a result of LQTS.
Patients may or may not have symptoms, but many physicians will choose to treat all patients with confirmed LQTS because of the risk of sudden cardiac death. The most common treatment is medication (e.g. beta blockers), and patients are often recommended to limit their physical activity. If symptoms persist, surgery to implant an artificial pacemaker or an implantable cardioverter defribrillator (ICD) may also be recommended.
MARFAN SYNDROME – Marfan syndrome is a rare genetic disorder of the connective tissue (the material that holds together the various structures of the body), which affects the formation and functioning of the heart valves, blood vessels, lungs, kidneys, eyes and skeleton.
Signs of the condition may include abnormally tall height or an off-center lens of the eye. Internally, Marfan syndrome patients have a larger and more fragile aorta – the main artery carrying oxygen-rich blood from the heart to the rest of the body. As a result, they could develop a number of heart-related conditions, including an aortic aneurysm, aortic dissection, aortic regurgitation, and/or mitral regurgitation.
Marfan syndrome patients are encouraged to stay in close contact with a team of healthcare professionals, including a cardiologist (heart specialist) and an ophthalmologist (eye) surgeon. Preventing or promptly treating an underlying problem generally means better prognosis for the patient. Also, male and female Marfan syndrome patients are encouraged to speak with a physician and a genetic counselor before making a decision about whether or not to conceive a pregnancy.
MYOCARDITIS – Myocraditis is an uncommon inflammation of the heart muscle (myocardium). Many people who develop myocarditis recover in a few weeks with few to no symptoms and no long-term complications.
Unfortunately, there are a small number of people who have severe symptoms, usually resulting in heart failure, and must spend time in the hospital. After recovering from the acute myocarditis, they may still need treatment for heart failure or other complications of the illness, including cardiomyopathy.
Depending on the cause, the symptoms of this condition may be very similar to the symptoms of the flu, so early diagnosis can be difficult. However, treatment is most effective when begun as soon as possible.
PATENT DUCTUS ARTERIOSUS – A patent ductus arteriosus is a heart defect that occurs when a blood vessel called the ductus arteriosus fails to close after birth, as it normally should. The ductus arteriosus is an open channel in the heart of every fetus that allows blood to bypass the lungs, which are not used by the fetus until it takes its first breath after birth. Shortly after the baby’s first breath, the ductus arteriosus should close permanently. If it does not, it is known as a patent, or open, ductus arteriosus (PDA).
Except for cases in which the baby has certain other heart defects that actually benefit from the presence of PDA (e.g. Tetralogy of Fallot), this condition can be harmful to the infant. If the PDA is very small, it may cause only mild symptoms or no noticeable symptoms at all. However, larger PDAs lead to the infant’s having difficulty breathing and poor growth. Particularly large PDAs can flood the lungs with blood, leading to acute heart failure.
Approximately 36,000 babies are born each year in America with heart defects, according to the American Heart Association. It is slightly more common among babies born at high altitudes and among females. It is most prevalent among premature and very low birth-weight (VLBW) babies. Fortunately, treatment is available. In premature infants, most PDAs can be closed with medication. Medication is not effective in full-term infants and older children, but catheter-based procedures or surgery is used to close the PDA in these patients.
PATENT FORAMEN OVALE – A patent foramen ovale (PFO) is an often-harmless heart defect. It is an opening between the upper two chambers of the heart (atria) that failed to close after birth, as it normally should. In most cases, this does not cause any problems.
However, it could cause symptoms such as difficulty breathing or recurrent respiratory infections. Rarely, large PFOs could cause heart failure or even death. SCUBA divers also seem to face slightly greater risk of stroke if they have a PFO. The condition has also been associated with a greater risk of pulmonary embolism.
PULMONARY ATRESIA – Pulmonary atresia is a very rare type of congenital heart defect in which the pulmonic valve is permanently closed or completely absent from the heart. This valve is normally responsible for opening and closing at precise moments to allow blood to flow from the heart through the pulmonary artery and to the lungs, where it is infused with oxygen. When the pulmonic valve is completely nonfunctioning, oxygen-poor blood cannot reach the lungs as it normally does.
Without treatment, a patient’s chance of long-term survival is poor because the body cannot get enough oxygen-rich blood. Fortunately, surgery is available to treat the problem, offering patients a greater chance of a healthier and more active life.
VENTRICULAR SEPTAL DEFECT – A ventricular septal defect (VSD) is a type of heart defect (congenital heart disease) in which there is a hole in the wall (septum) between the heart’s lower chambers (ventricles). It is the most common congenital heart defect.
VSDs vary in size, from a mere pinpoint to the almost total absence of the septum. Also, they may occur in isolation or as part of a more complex series of congenital defects. The symptoms and severity of a VSD depend on how large it is. The vast majority are small, without symptoms and spontaneously close within the first three years of life.
Larger VSDs, however, can be dangerous. Because the pressure on the left side of the heart is greater than the pressure in the right side, the hole allows blood to seep from the left ventricle into the right ventricle. This results in too much blood volume in the right side of the heart and lungs. The more blood that is diverted to the right side of the heart, the harder the lungs and right ventricle must work. Eventually, the stress on the right ventricle can cause it to weaken and/or enlarge (dilate) to compensate for the increased workload. Also, the lungs can become congested upon receiving more blood than is needed.
Other consequences of a VSD include chest infections, pulmonary hypertension (high blood pressure in the lung’s blood vessels), the formation of blood clots (which could lead to stroke), and the development of abnormal heart rhythms (arrhythmias).
For VSDs that remain open, most physicians agree that no matter how small the hole is, it should be treated sooner rather than later – especially if other defects are present. Treatment usually involves surgery.
WOLFF PARKINSON WHITE SYNDROME – Also known as preexitation syndrome, Wolff-Parkinson-White (WPW) syndrome is a condition in which there is extra, abnormal electrical pathway in the heart that can cause an abnormal heart rhythm (arrhythmia). The condition is believed to be present from birth (a congenital heart defect). In most cases, WPW causes symptoms only when the heart rate is very fast (tachycardia). In other cases, the condition causes no symptoms at all. However, all cases carry a very small risk of developing a potentially fatal heart rhythm known as ventricular fibrillation.
Some patients do not need treatment for WPW, either because they have no symptoms or because the WPW resolves on its own as patients get older. Other cases will require treatment, including a minimally invasive procedure called catheter ablation that destroys the abnormal pathway or (rarely) open-heart surgery. Medications (e.g. antiarrhythmics) may also be prescribed.