What is Loeys-Dietz syndrome? This rare condition is caused by a genetic change that affects the body’s connective tissue. While similar to Marfan syndrome, it has unique features that may affect other parts of the body. It can lead to:

• Widely spaced eyes
• Cleft palate or wide uvula
• Skeletal conditions such as scoliosis (curved spine), a protruding or sunken chest, or a clubfoot

How it affects the heart: Loeys-Dietz syndrome causes problems with the aorta. A patient’s aorta may stretch, causing a bulge (aneurysm). The aorta and other arteries may also tear (aortic dissection).

Loeys-Dietz care at Doernbecher: To slow aneurysms, the doctor may recommend medications to lower blood pressure. Sometimes surgery is needed to replace the diseased blood vessel. Learn more about the specialized care in our aortopathy program.

What is Marfan syndrome? Like Loeys-Dietz syndrome, this condition is caused by a genetic change that affects connective tissues. Marfan syndrome is most often inherited from a parent. About 20% of the time, the genetic change is random.

• Children with Marfan syndrome often have long arms, legs, fingers and toes.
• The syndrome can lead to issues related to your child’s blood vessels, skeleton, eyes, lungs and heart.
• Some children have only mild symptoms.

How it affects the heart: Marfan syndrome can cause problems with the aorta. Pressure from blood pumped out of the heart can cause the aorta to bulge (an aneurysm) or tear (dissection). Children with Marfan syndrome may also have weaker heart valves, leading to mitral valve prolapse or mitral regurgitation.

Marfan care at Doernbecher: To slow the formation of aneurysms, your child’s doctor may recommend medications to slow heart rate and lower blood pressure. Patients also have monitoring to check for aneurysms. Sometimes surgery is needed to repair an aneurysm or to repair or replace the mitral valve. Dr. Kathryn Holmes and Dr. Lars Grosse-Wortmann are among team members with particular expertise in Marfan syndrome and aortopathies. Learn more about our complete care for aortopathies.

What is Noonan syndrome? This condition is caused by changes in one of several genes. Children with Noonan syndrome may be short. They also may have unusual facial features, developmental delays and skeletal abnormalities.

About one in 2,500 babies is born with Noonan syndrome. It more often affects boys and is usually inherited from a parent. Sometimes it happens without any family history.

How it affects the heart: About two-thirds of children with Noonan syndrome are born with a heart defect, most commonly:

• Pulmonary valve stenosis, a narrowing of the valve that sends blood from the heart to the lungs
• Atrial septal defect, an opening between the heart’s two upper chambers

Less common disorders include:

• Ventricular septal defect
• Patent ductus arteriosus
• Atrioventricular defect

Some children with Noonan syndrome develop hypertrophic cardiomyopathy, a thickening of the heart muscle.

What is Trisomy 21? Trisomy 21 is the most common chromosomal disorder and cause of learning issues in children. Children with Trisomy 21 have an extra copy of chromosome 21, which commonly leads to developmental delays. It can be diagnosed with genetic testing before birth.

How it affects the heart: About half of children with Down syndrome are born with a congenital heart defect such as a septal defect (hole in the heart). Often, these disorders are mild and don’t need treatment. Some need to be repaired with surgery.

What is Turner syndrome? This condition affects only girls. It’s caused when one copy of a child’s X chromosome is missing or incomplete. One in 2,000 to 2,500 girls is born with Turner syndrome. In some cases, it’s diagnosed before birth, or shortly after. Mild cases may not be diagnosed until adulthood.

• People with this condition tend to be shorter, with undeveloped ovaries and delayed puberty.
• Other symptoms include abnormalities of the eyes, ears, bones and kidneys.

How it affects the heart: Turner syndrome can affect the walls of the aorta and the aortic valve. The most common condition related to Turner syndrome is bicuspid aortic valve. The baby is born with two flaps in the aortic valve instead of three. A smaller portion of girls has coarctation, or narrowing, of the aorta.

Turner care at Doernbecher: Dr. G. Michael Silberbach, a national expert in Turner syndrome, leads our program. We offer a clinic that brings together specialists to treat the conditions caused by Turner syndrome, including high blood pressure, infertility and autoimmune disorders.

What is 22q11.2 deletion syndrome? This disorder happens when a child is missing a tiny part of chromosome 22. About one in 2,000 to 4,000 children is born with 22q11.2 deletion syndrome. Most are from a random genetic change.

It can cause health issues that include:

• Cleft palate
• Feeding difficulties
• Unusual facial features
• Hearing loss
• Speech disorders
• Learning and behavior issues
• Kidney problems
• Difficulty fighting infections

How it affects the heart: Most children with 22q11.2 deletion syndrome are born with a heart defect such as:

• Interrupted aortic arch
• An abnormal pulmonary valve
• Atrial septal defect
• Tetralogy of Fallot
• Truncus arteriosus
• Ventricular septal defect

What is Williams syndrome? This rare condition affects one in 10,000 babies. It’s caused by a random deletion of genes on chromosome 7. It can lead to:

• Unusual facial features
• Connective tissue and joint disorders
• Learning delays
• Distinctive personality traits
• Developmental delay

How it affects the heart: Three in four children with Williams syndrome are born with a heart defect. Narrowing of the aorta (aortic stenosis) and other arteries is the most common.

Other genetic syndromes that affect the heart include:

• Alagille syndrome: This disorder can affect the liver, heart and other body parts. Symptoms can range from mild to severe. It’s linked to pulmonary stenosis (narrowing or stiffening of the pulmonary valve) and a combination of heart defects called tetralogy of Fallot.
• CHARGE syndrome: CHARGE syndrome can affect the eyes, ears, heart and other body parts, including the nerves from the brain to the body. It can also affect growth and development. About three in four patients have a congenital heart condition that can range from mild to severe.
• Cornelia de Lange syndrome: Children with this rare disorder typically have slow growth, bone anomalies, and mild to severe intellectual disabilities. Other conditions linked to this syndrome include congenital heart disease, such as ventricular and atrial septal defects.
• Ellis-van Creveld syndrome: Children with this disorder have extra fingers and/or toes and abnormally short limbs. Most are also born with a heart defect, most commonly an atrial septal defect.
• Holt-Oram syndrome: This rare condition affects development of the bones and heart. Many children with Holt-Oram syndrome have missing or underdeveloped bones in their hands, forearms or shoulders. Three in four have a heart defect, most often a ventricular or atrial septal defect.
• Kabuki syndrome: This condition can affect many systems in the body, including the heart. Patients typically have delayed growth, bone anomalies, and mild to moderate intellectual disabilities. Congenital heart defects linked to Kabuki syndrome include coarctation (narrowing) of the aorta, and ventricular or atrial septal defects.
• VACTERL association: Children with this complex condition typically have birth defects in several parts of the body, such as the kidneys, limbs and heart. Symptoms vary widely. Congenital heart defects linked to this condition include ventricular septal defects.
• Wolf-Hirschhorn syndrome: This rare syndrome can come with problems in growth and development. Symptoms vary greatly. Patients also often have intellectual disabilities and other conditions, including heart defects.