CONGENITAL HEART DEFECTS (CHDS): RARE, COMMON, AND POSSIBLY LIFE-THREATENING

Medically reviewed by Christopher Lee, MDMedically reviewed by Christopher Lee, MD

A congenital heart defect (CHD) is a structural heart problem present at birth. CHDs are the most common type of congenital condition, seen in about 1% of all newborns in the United States. CHDs range in severity; some mild CHDs resolve on their own, but complicated and severe cases can be life-threatening and require immediate treatment and long-term care.

Researchers have identified at least 18 distinct types of CHDs, categorized by the part of the heart affected: septal defects, heart valve defects, and large blood vessel defects. Healthcare providers further divide these into simple CHDs, which may not require surgery, and critical CHDs, which are complex and may require emergency care.

Types of Congenital Heart Defects

Atrial Septal Defect

An atrial septal defect (ASD) affects the septa (walls) separating the heart’s upper right and left chambers (the atria). As the fetus’s heart develops during pregnancy, these holes typically close before or shortly after birth. ASD arises when one or more remain open.

Researchers have linked ASD to genetic and chromosomal abnormalities. Certain behaviors and conditions during pregnancy raise risk:

  • Advanced maternal age (35 or older) 
  • Alcohol consumption
  • Cigarette smoking
  • Diabetes and/or obesity
  • Taking certain antidepressants

Ventricular Septal Defect

Ventricular septal defects (VSDs) can affect different parts of the septum that separate the heart's lower left and right chambers (ventricles). Researchers believe that genetic and environmental factors contribute to VSD. They have observed specific genes and chromosomal differences associated with VSD, as well as smoking, drinking alcohol, and diabetes during pregnancy.

Patent Ductus Arteriosus

During fetal development, the ductus connects the pulmonary artery and aorta. The goal is to move the already oxygenated blood away from the blood vessels in the lungs to the systemic circulation. In patent ductus arteriosus, the duct does not close properly and affects blood flow to the lungs.

Genetics plays a role in patent ductus arteriosus, but researchers don’t know the causes. Risk factors for this condition include:

  • Char syndrome (a genetic disorder that affects face, hand, and heart development)
  • Congenital rubella syndrome, which arises due to rubella virus infection during pregnancy
  • Having a sibling with patent ductus arteriosus
  • Pregnancy and birth in higher altitudes
  • Premature birth

Pulmonary Stenosis

Pulmonary stenosis is stiffness and narrowness of the pulmonary valve, which controls blood flow from the right ventricle to the pulmonary artery. Because of the reduced blood flow, the right ventricle pumps harder, which can damage the heart muscles.

Pulmonary stenosis is among the more common CHDs, though researchers don’t fully understand what causes it. Risk factors include:

  • Chromosomal abnormalities
  • Genetic disorders such as Noonan and Williams-Beuren syndromes, which affect facial features, height, and other features
  • Inherited genetic disorders
  • Other CHDs
  • Rubella, a viral infection, during pregnancy

Tetralogy of Fallot

Tetralogy of Fallot is a critical CHD that occurs when four simple defects happen at the same time:

  • Overriding aorta, in which the aorta runs over a ventricular septal defect rather than the left ventricle
  • Pulmonary stenosis
  • Right ventricular hypertrophy, enlarged and thickened muscles surrounding the right ventricle
  • Ventricular septal defect

Research suggests that tetralogy of Fallot results from genetic and environmental factors. Alcohol use, smoking, and diabetes during pregnancy raise the chances of the fetus developing this condition.

Complications and Risks of Congenital Heart Defects

CHDs can cause serious complications. Severe and complicated cases are sometimes life-threatening without immediate surgery. Other potential complications include:

  • Arrhythmia, irregular heartbeat
  • Endocarditis (an infection of the tissues lining the heart)
  • Heart failure (when the heart cannot pump sufficiently)
  • Kidney and liver disease
  • Pulmonary hypertension (characterized by high blood pressure in the lungs)
  • Shorter stature
  • Speech and language difficulties

Living With a Congenital Heart Defect

Effect on Life Expectancy 

The outlook for CHD has improved with advances in CHD diagnosis and treatment. Currently, most babies born with this condition live to see adulthood. Life expectancy varies and depends on the defect's type and severity, diagnosis timing, and treatment efficacy.

Researchers found that 97% of babies born in first-world countries with simple CHDs and 75% of those with a critical case survive infancy. About 81% of those with CHD live to 35 years or older, and nearly 75% of those with CHD reach their 60s. That said, mortality—the chance of death—is higher in those with CHD.

Role of Treatment

Complex CHDs are medical emergencies requiring immediate, life-saving surgery or treatment. While milder congenital heart defects may not call for medical interventions, this condition requires long-term management and lifelong follow-up.

For Parents 

If your child has a CHD, there are several things you can do to help manage it:  

  • Understand the condition: Learn about your child’s condition and keep track of their treatments and any medications they take.
  • Regular care: Take your child to follow-up appointments.
  • Tooth care: Make sure children are brushing and flossing daily, and help toddlers take care of these important tasks. People born with a CHD are at an increased risk for infective endocarditis, a heart infection caused by bacteria in the mouth.
  • Promote physical activity: Getting enough physical activity can be critical for heart health; ask your child’s healthcare provider what activities are safe.
  • Nutrition: Ask your healthcare provider about dietary plans and approaches to support your child’s growth.

Symptoms of CHDs Before Birth

During pregnancy, you won’t be able to tell if the fetus is developing a CHD. However, healthcare providers can detect signs of the condition in fetuses. They use fetal echocardiogram, a form of imaging that relies on sound waves, to assess a developing heart. Typically, healthcare providers perform a fetal echocardiogram in the second trimester, between weeks 18 and 22 of pregnancy.

These images can help healthcare providers detect the early signs of some types of CHD. Prenatal detection can allow you and your family to prepare for the condition and learn about your options.

Minimizing CHD Risks During Pregnancy

If you’re expecting or planning to become pregnant, there are several steps you can take to help prevent CHD:

  • Avoid alcohol consumption during pregnancy.
  • Avoid medications that increase risk, such as certain angiotensin converting enzyme (ACE) inhibitors, lithium, and Claravis (isotretinoin).
  • Meet with a genetic counselor if you have a family history of CHD or are at increased risk.
  • Quit smoking.
  • Treat any existing cases of diabetes or phenylketonuria (a genetic disorder that causes amino acid build-up in the blood).

Related: Sonography: How a Sonogram Test Works and What It Shows

Symptoms of CHDs After Birth

Infants and Children

CHD in infants and children can cause several signs, including:

  • Cyanosis, a bluish tint to the skin, lips, and fingernails
  • Fast or shallow breathing
  • Heart murmur, unusual whooshing or swishing sounds between heartbeats
  • Poor blood circulation, causing cold fingertips and toes
  • Sleepiness and fatigue

Into Adulthood 

Some CHDs can cause no symptoms until adulthood, including small atrial septal and ventricular septal defects. The signs in adults are similar to those in infants and include:

  • Cyanosis
  • Dizziness
  • Fatigue
  • Heart murmur
  • Heart palpitations, irregular or fluttering heartbeat
  • Shortness of breath
  • Swelling in the ankles, feet, or hands

Treatment Options to Manage CHDs

Surgery

Healthcare providers use surgical intervention in more severe cases that cause problematic symptoms. The type of surgery depends on the CHD. It could include heart surgery to repair the heart or place an assistive device, palliative surgery to support heart function in infants who aren't strong enough to tolerate reparative surgery, or, in severe cases, a heart transplant.

Cardiac Catheterization

Cardiac catheterization is a nonsurgical procedure used to treat CHDs like atrial septal defect, patent ductus arteriosus, and tetralogy of Fallot. The provider inserts a flexible tube, or catheter, into blood vessels in the groin or neck and runs it to the heart, which allows them to use tools and devices to repair or replace valves.

Medications

While patent ductus arteriosus often resolves on its own, healthcare providers may prescribe medications to treat cases in premature infants. Tivorbex (indomethacin), intravenous (IV) ibuprofen (the same drug in the popular over-the-counter brands Advil and Motrin), or Ofirmev (acetaminophen IV, an intravenous form of the popular drug Tylenol) tighten and close the patent ductus arteriosus.

CHD Awareness

It may help to be reminded that, whether you are caring for someone with a CHD or are living with a CHD, you are not alone. Here’s where you can look for support:

Care for congenital heart defects has advanced over the years, and the future looks even brighter. Researchers continue to develop novel treatments and techniques, such as using cross-sectional imaging for catheterization or new fetal surgeries.

Summary

Congenital heart defects (CHDs) are abnormalities of the heart’s structure that are present at birth. CHDs range in severity; more mild cases may not require treatment, while others are medical emergencies. Researchers don’t know the exact causes but believe the condition arises due to genetics and health factors during pregnancy.

Due to improvements in care, most people born with CHD live well into adulthood. The outlook continues to improve for those with this condition.    

Read the original article on Verywell Health.

2024-09-18T19:48:02Z dg43tfdfdgfd