Familial Isolated Congenital Heart Disease

A congenital heart condition (often referred to as a congenital heart defect, or CHD) is a structural problem of the heart that develops during pregnancy. About one out of 100 children is born with CHD. There are many types of congenital heart defects, ranging from simple to complex, and most are diagnosed and treated early in infancy.

Familial isolated congenital heart disease is a congenital heart condition that is both familial and isolated. The term familial means CHD appears to run in a family (inherited from generation to generation), potentially affecting siblings, parents, aunts and uncles, and grandparents. The term isolated means that the CHD is not associated with other medical diagnoses or structural abnormalities of other organs.

There are many different types of congenital heart conditions that can be familial and isolated, including:

• Atrial septal defect (ASD)
• Ventricular septal defect
• Patent ductus arteriosus
• Tetralogy of Fallot (TOF)
• Double outlet right ventricle (DORV)
• Pulmonary valve stenosis
• Transposition of the great arteries (TGA)
• Atrioventricular canal defect
• Coarctation of the aorta
• Hypoplastic left heart syndrome (HLHS)
• Bicuspid aortic valve

The symptoms of familial isolated congenital heart disease can look different among individuals. Specific symptoms of CHD in infants and children include:

• Cyanosis (a bluish tint to the skin, fingernails, and lips)
• Respiratory distress
• Poor feeding
• Poor weight gain
• Recurrent lung infections
• Diminished ability to exercise or actively play compared to other children

With familial isolated congenital heart conditions, family members can have either the same type of congenital heart condition or they may have different types. The complexity of a CHD can also vary within families. In other words, it is possible that not all family members will have the same type or severity of congenital heart disease.

There are many different causes of CHD. However, when it is seen in multiple family members, it may be due to a genetic cause. A genetic cause means there was a genetic change (also known as a genetic variant or mutation) in the DNA that is associated with the probability of developing a congenital heart condition.

Some children may be the first to have a congenital heart condition in their family. When this occurs, a genetic change may have happened by chance and was not inherited from either parent. In other cases, a genetic change can be passed down from parent to child.

Sometimes congenital heart defects are discovered before a child is born through a prenatal ultrasound. Some types of complex CHDs are apparent shortly after birth. Less severe defects may not be found until a child is older. Some CHDs are discovered after a doctor hears a heart murmur.

Children with a family history of heart conditions may have an echocardiogram soon after birth to determine if they have CHD. When a child is diagnosed with a congenital heart defect, cardiac imaging and tests may be recommended for immediate family members (siblings, mother, and father). Even if a family member does not have known symptoms, they could have very mild congenital heart disease that would not otherwise be detected without specific cardiac evaluation.

Genetic testing can also help identify a cause for CHDs. Identifying a genetic cause allows other at-risk family members to have targeted testing to confirm the presence or absence of that same genetic change. The genetics specialists of Boston Children’s Center for Cardiovascular Genetics can help your family understand the process and results of genetic testing for familial isolated congenital heart disease.

Treatment is based on the specific type and severity of congenital heart defect you or your child has. Some mild heart defects don't need treatment. Others can be treated with medications, interventional procedures, or surgery. In some cases, if CHD is found prenatally, it’s possible to perform a procedure on the child before they are born.

The Center for Cardiovascular Genetics is a team of experienced cardiologists, geneticists, genetic counselors, and nurse practitioners who are familiar with the complexities of familial isolated congenital heart conditions. Our team works with children and their families to provide comprehensive care and promote understanding of the CHDs affecting families.