Heart Defects at Birth May Affect Heart Rhythm—Even Years Later

Are you at risk for arrhythmia later in life? Learn how heart defects can affect your long-term health.

Older black woman in hospital bed with male doctor with stethoscope

Odds are, you’ve heard of a congenital heart defect (CHD). It’s the most common type of birth defect—a problem with one or more structures of the heart that develops in the womb and is present when a baby is born. The Centers for Disease Control and Prevention (CDC) estimates that each year, nearly 1 percent of children are born with a CHD. These defects can range from mild to serious. Some may require surgery and could lead to other health problems.

One of these problems is an abnormal heartbeat, called an arrhythmia. When you have an arrhythmia, your heart beats too quickly, too slowly or in an erratic pattern. Arrhythmias can hinder blood flow to the body, damaging organs and contributing to a range of potentially life-threatening health conditions, including cardiac arrest and stroke. 

People with a CHD are more prone to arrhythmias than people without a CHD, since variations in heart structure and function can influence how the heart beats. Arrhythmias can be caused by a CHD itself or from scarring that forms after surgery to correct a CHD. They may occur at any time in CHD patients—at birth, during childhood or later on in life. Fortunately, healthcare providers may be able to detect and treat these arrhythmias before they become even more serious issues.

Risk factors for CHDs

Many CHDs and associated arrhythmias have roots in early pregnancy, when the heart is developing. Though the exact cause of an individual CHD is often unknown, gene mutations and chromosomal conditions may be significant factors, likely in combination with exposures during pregnancy.

“There are certain commonly used medications moms might take that lead to rhythm disturbance,” says Charles Fuenzalida, MD, an electrophysiologist with Aurora Denver Cardiology Associates, who practices at The Medical Center of Aurora, in Aurora, Colorado. These medications include statins, ACE inhibitors, lithium, thalidomide and an acne drug called isotretinoin. 

Other possible contributors include having a certain health condition during pregnancy, such as diabetes, rubella or lupus. Drinking or smoking during pregnancy can play a role, too.

Arrhythmias linked to CHDs

There are many kinds of arrhythmias that someone may develop as a result of a CHD. In one kind of arrhythmia, called tachycardia, the heart beats too fast. Tachycardias include, but are not limited to:

  • Supraventricular tachycardia (SVT): SVT often starts in the heart’s upper chambers, called the atria, and is characterized by a sudden, very rapid heartbeat. SVT affects up to 20 percent of adults with congenital heart disease, according to the American College of Cardiology.
  • Ventricular tachycardia: Like SVT, ventricular tachycardia is characterized by a faster-than-normal heartbeat, but it originates in the heart’s lower chambers, called the ventricles. It is considered a life-threatening condition and is less common than SVT.
  • Atrial fibrillation (AFib) and atrial flutter: These tachycardias begin in the atria and increase the risk of stroke. During AFib, the atria beat wildly and out of sync with the ventricles.

In another form of arrhythmia called bradycardia, the heart beats too slowly. Common bradycardias associated with CHDs include:

  • Sinus node dysfunction: This commonly occurs after surgery to fix a CHD. The sinus node is often referred to as the heart’s “natural pacemaker” since it keeps the electrical system that regulates heartbeats running smoothly. 
  • Heart block: This occurs when the heart’s electric signals aren’t able to get from the atria to the ventricles; they’re slowed or entirely blocked.

Another type of arrhythmia: premature or irregular heartbeats, which frequently occur in young children. They’re typically considered normal and relatively minor, though they can be linked to an underlying CHD or CHD surgery.

Symptoms of an arrhythmia

Arrhythmias are common and may be caused by a range of factors outside of CHDs. In children, these include infections, fevers and some medications. In adults, arrhythmias can be triggered by anything from stress to an in-progress heart attack. 

In both children and adults, many arrhythmias are asymptomatic, meaning they don’t have symptoms; these are often relatively harmless and may be discovered during a routine physical exam. They may not need treatment.

When there are symptoms, it can indicate a more serious issue. In addition to a slower, faster or irregular heartbeat, look out for:

  • Weakness
  • Dizziness
  • Fatigue
  • Pale skin
  • Sweating
  • Heart palpitations, or feeling like the heart is “fluttering” or skipping beats
  • Feeling faint or fainting
  • Shortness of breath
  • Chest pain (relatively rare in kids)

Children may not be able to articulate exactly how they’re feeling, which can make diagnosing a congenital arrhythmia more difficult. So, in infants and very young children, be aware of general irritability and feeding problems, as well.

If an abnormal heartbeat occurs alongside any of these symptoms or it persists over an extended time period, reach out to your healthcare provider (HCP).

Diagnosis and treatment

The accurate diagnosis of an arrhythmia means treatment can get started—preventing further complications—and may indicate a potentially dangerous underlying health condition, including a CHD you may not have been aware of. 

If your HCP suspects an arrhythmia, they’ll likely begin the diagnostic process by getting a medical history and performing a physical exam. The next step is often an electrocardiogram (EKG or ECG), a painless test that measures electrical activity of the heart. 

Sometimes, additional testing is necessary. For example, patients may have to wear a Holter monitor over a day or two to record the heart’s electrical activity, or they may need to undergo an echocardiogram—a test that uses soundwaves to create a moving image of the heart. Cases involving children may be referred to a pediatric cardiologist, a doctor specializing in kids’ heart conditions.

Treatment for arrhythmia for those with a CHD hinges on several factors, such as their age, the severity of their symptoms and their specific heart defect. Treatment frequently takes one of two paths, notes Dr. Fuenzalida. “The solution often is to use medications to suppress the irregular heartbeat,” he explains. “The other thing we do is go in and look for signs of irregularity. Then we cauterize it and get rid of it—that’s called an ablation.”

Sometimes, implantable devices like pacemakers and defibrillators are necessary to maintain a regular heart rhythm. Surgery isn’t typically recommended unless other treatments fail. 

Even after treatment, people born with heart defects require lifelong monitoring and regular visits to a cardiologist. Since some CHDs are hereditary, genetic counseling for prospective parents with CHD is often recommended prior to pregnancy. 

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