Many individuals with LVNC experience no symptoms. Symptoms can develop at any age and many patients often go undiagnosed until later in life. For those who have heart failure or an abnormal heart rhythm, symptoms may include:

Newborns and babies

• Difficulty feeding or poor growth
• Excessive sweating during feeds or activity

Older children and adults

• Shortness of breath and fatigue
• Feeling dizzy or light-headed
• Fainting or passing out (syncope)
• Feeling abnormal heart beats (palpitations)
• Unexplained weight gain or swelling

While some children who have LVNC experience no symptoms, they may still be at risk for complications of the condition. The most serious is sudden cardiac arrest, which is a loss of heart function caused by a dangerously fast heart rhythm called ventricular tachycardia.

Without immediate emergency treatment, such as CPR and defibrillation, cardiac arrest may lead to death.

When an individual is diagnosed with LVNC, there is a 20 to 40 percent chance that an underlying genetic cause will be identified. Most commonly, the genetic cause results in a condition that runs in a family and affects only the heart. It is possible that parents, siblings and even aunts / uncles or cousins of an individual with LVNC may also have this heart muscle condition.

There are other genetic causes of LVNC, which can be associated with other health problems. These include genetic syndromes, metabolic and mitochondrial disorders. It may also be seen in association with congenital heart disease, which is a structural change in the heart. There are no known acquired cases of LVNC.

The following are possible methods of diagnosing LVNC:

• Medical history of heart failure symptoms including feeding issues, rhythm problems and exercise intolerance
• Physical exam to assess skeletal muscle strength and identify signs of possible cardiac problems
• Echocardiogram – noninvasive ultrasound test that uses sound waves to produce images of the heart
• Genetic Testing — to determine whether or not a genetic mutation is present
• Family history of cardiomyopathy, rhythm problems, sudden cardiac or unexplained death, cardiac surgery or presence of other cardiac disease in relatives.

Echocardiogram is the most common test used to diagnose LVNC, as the bundles of muscles (trabeculations) and overall squeeze of the heart can be measured with this test.

It is recommended that all family members (parents, siblings, children, grandchildren, uncle, aunt, nephew, niece) be evaluated carefully for this form of cardiomyopathy, even if they have no symptoms.

A genetic counselor and / or geneticist can assess the family history and provide information about the chances of a genetic predisposition to cardiomyopathy.

Please read more about genetic testing for cardiomyopathy.

Treatment for children with LVNC is focused on the associated types of heart muscle disease such as a thick heart muscle (hypertrophic cardiomyopathy) or poorly squeezing heart muscle (dilated cardiomyopathy). The primary goal is to improve the function of the heart and to prevent symptoms.

The following may be methods of treatment for your child’s LVNC:

• Medications are used to treat symptoms, reverse heart damage and prevent ongoing damage to the heart muscle
• Blood thinners (e.g., aspirin) may be prescribed for children with decreased heart function (who are at increased risk for clot between the muscle bundles in the heart)
• Lifestyle changes such as limited activity when tired, dizzy or if the child has difficulty breathing
• Surgical procedure(s) to reduce muscle wall thickness

In serious cases of heart failure, the child may need the following:

• Implantable cardioverter-defibrillator (ICD) – an automated device placed under the skin that tracks the heart rate and sends electrical signals to the heart if it detects abnormalities
• Pacemaker (cardiac resynchronization therapy) – commonly combined with ICD treatment. It is a small device placed in the body to control heart rhythms
• Berlin heart device – a mechanical device placed in the body to help the heart pump and supply blood to the body
• Heart transplant is considered for children with severe, life-threatening heart failure