Did you know that:
Each year an estimated 7,000 children and infants die in the United States from sudden cardiac arrest1
Heart screenings could have detected 70% of the cardiac arrhythmia syndromes causing sudden death
1 out of every 350 children has a congenital cardiovascular defect
Approximately 2% of youth that are heart-screened are diagnosed with a heart abnormality or concern
1% are diagnosed with a life-threatening heart condition
The first symptom in over 80% of cases of sudden cardiac arrest is death
The fact is that most youths in our country are not adequately screened for existing heart conditions. Most youth who suffer Sudden Cardiac Arrest have an undetected heart condition.
A thorough family history and physical examination that includes a baseline test utilizing an electrocardiogram (also known as an ECG or EKG) can help detect approximately 70% of the heart conditions that can lead to Sudden Cardiac Arrest.
Problems with the heart’s electrical control system:
A heartbeat is caused by an electrical signal traveling through the heart. The electrical signal functions as the heart’s natural pacemaker. The electrical signals travel through the heart tissue causing the contraction and relaxation of the heart, in turn causing the blood to be pumped to the lungs where it picks up oxygen and is then pumped once again throughout the body
Sudden Cardiac Arrest can be caused by defects in the heart’s electrical control system. Some of the common defects of this type are:
An abnormality of the heart cells that disrupts the electrical activity in the heart and can cause life-threatening heart rhythms.
Blackouts, palpitations and sudden death.
There are no physical signs associated with Brugada Syndrome.
Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Characterized by exercise or stress-induced ventricular arrhythmias in which the heart’s lower pumping chambers go into very rapid and uncontrolled rhythms that no longer pump blood effectively.
This is a rare condition found in young people who can black out or die suddenly when exerting themselves.
The diagnosis only appears to be easily made when these rhythm disturbances have been recorded and recognized. Those with CPVT respond dramatically to beta-blockers and a restriction of physical activity, and have a much better outlook following treatment.
Long Q-T Syndrome (LQTS)
A disturbance of the heart’s electrical system. A genetic mutation causes a defect in the heart cells, called ion channels, which then prolongs the time the heart takes to electrically recharge after each heartbeat (known as the QT interval). LQTS is usually inherited. In other cases, LQTS can be caused by certain medicines, toxins, electrolyte disturbances, or other forms of heart disease.
The “QT” interval refers to a specific measurement on the electrocardiogram, the record of the electrical activity of a person’s heart. A “QT” interval is measured in seconds or in milliseconds. “Long QT” means the QT interval lasts longer than normal.
A prolonged QT interval occurs when the cells of the ventricles (the lower chambers of the heart) don’t electrically reset at the same time or take longer than normal to reset. This can allow for an arrhythmia, or abnormal heart rhythm, to occur that can be potentially lethal. However, there are some QT intervals that are at the borderline duration that still may be considered normal. A person has LQTS when there is abnormal prolongation of the QT interval that can cause certain symptoms, such as fainting.
In most cases LQTS is inherited, or caused by a genetic mutation that is passed down through a family. It can also be caused by certain medications. LQTS can manifest in different forms and can be difficult to diagnose.
There are three major types of LQTS. Treatment for your child may depend on which type of LQTS he/she has.
LQT1: Individuals with LQT1 are more likely to have symptoms while exercising, although symptoms can occur with emotional stress and even when resting. It can be treated effectively with beta blocker medication in most patients. It is important for individuals with LQT1 to maintain normal potassium levels and lifestyle modifications in addition to taking their prescribed medications.
LQT2: Individuals with LQT2 are more likely to have symptoms with emotional stress, but symptoms can also occur during exercise and when resting. LQT2 can be treated moderately well with beta blocker medication, but treatment may be improved by also maintaining a good potassium level. Of the three major LQTS types, LQT2 is most affected by medications that further prolong the QT interval.
LQT3: Individuals with LQT3 are more likely to show symptoms during rest. LQT3 is less well treated with beta blocker medication than other types of LQTS, but beta blocker medication is still effective in many of these patients. LQT3 patients with symptoms may need to take another medication in addition to beta blockers. Some patients may need an implantable cardioverter-defibrillator (ICD).
The most common symptom are blackouts. Other symptoms include heart palpitations, dizzy spells and chest pain. Very often, symptoms are not reported or felt at all. Too often, sudden death is the first presentation of the defect. There is a wide variance in the severity of the condition and the results of having them.
Sudden death in Long QT 1 is most commonly seen after physical exertion. In Long QT 2, sudden death is usually seen during some type of emotional stress, which may be brought on by sudden, loud noises such as the ringing of a phone or alarm clock, etc.
In Long QT 3, sudden death has been increasingly noted during sleep.
There are no physical signs that a child may be afflicted by the condition.
This involves observation of the ECG for the lengthening of the QT interval and abnormality of other parts of the ECG that represent repolarisation. These are the T Waves. Unfortunately, the wide spectrum of the condition means that many individuals might be carriers but not exhibit any ECG changes. It may require repeated ECGs, exercise tests and 24-48 hour tape monitoring to see any hint of the condition.
If a child has repeated fainting episodes, or other symptoms, a pediatrician may refer him or her to a pediatric cardiologist. It is not unusual for individuals with LQTS to have no symptoms until the teenage or early adult years.
LQTS is diagnosed by a cardiologist, with the use of an electrocardiogram, also known as an ECG or EKG. Evaluation may also include the wearing of a Holter monitor and /or exercise stress testing
Because the condition is usually inherited, your cardiologist may consider genetic testing and counseling. If a child has LQTS, brothers, sisters, parents and other family members may also have it.
If a person has LQTS and isn’t treated, the risk of sudden death over a lifetime is high.
A person that has LQTS may need to:
take medications known as beta blockers
avoid the triggers that may cause an arrhythmia event
avoid certain medications
have a special pacemaker (ICD) installed via surgery
Some children with LQTS have to limit competitive sports and other exercise. It is particularly dangerous for a person with LQTS to have low levels of electrolytes (sodium and potassium are two examples of electrolytes). Remaining hydrated by drinking water or sports drinks (which contain electrolytes) is important, particularly before, during and after exercise.
A child will not outgrow LQTS, however most children and adults with LQTS are able to lead healthy, normal lives. He or she will have to continue following any prescribed treatment, and will need life-long care by a cardiologist.
There are several other types of heart conditions that place our youth at risk. To help reduce the risk that your child or loved one suffers or dies due to Sudden Cardiac Arrest, take the following steps:
Find out about your family history. Have there been any heart issues? Have any children passed away at an early age? Are there fainting spells?
Ask your child’s physician about the health of the child’s heart. Has it been checked properly?
At minimum, an ECG (EKG) should be performed and read by a qualified cardiologist
Know the warning signs and symptoms. Take action immediately if you child exhibits any of them
Learn CPR and how to use an AED. Find out if your child’s schools are equipped with an AED
1The Heart Rhythm Society