Fainting

     Fainting is not lightheadedness or dizziness. It is a sudden, brief loss of consciousness in which the child “passes out” for a short time and then “comes to” and is all right. About one in every six children experience fainting sometime before adulthood. Most fainting in children is called vasovagal syncope (syncope means “fainting”) and is caused by a temporary slowing of the heart rate that causes less blood to flow to the brain and causes the child to faint. Along with having a slow heart rate, the child’s skin is pale, clammy and cold. The child rapidly regains consciousness and has no other problems after he wakes up. A fainting episode is harmless, although the child might sustain an injury from falling when he faints. Fainting commonly occurs when the child rapidly stands up from a sitting or lying position, is under stress or is in warm or crowded conditions (it often happens at church).

    However, there are other causes of fainting that are dangerous and parents should know how to tell the difference. The most dangerous form of fainting is caused by an abnormality of the heart. A study of 106 children who were seen for fainting found that 17 of them had heart trouble as a cause of their fainting. One of the most common heart problems is called hypertrophic cardiomyopathy. This is an inherited tendency for a chamber of the heart to gradually enlarge as the child gets older until it can no longer pump enough blood. This condition is the reason for most of the reports of an adolescent suddenly falling dead while playing a sport. These children often have no symptoms of their problem other than having fainting episodes while exercising. Any child who has a family history of sudden cardiac death during exercise needs to be closely examined before being allowed to exercise and any child who has a fainting episode during exercise needs a full heart evaluation including an electrocardiogram (EKG).

     Fainting can be a sign of other heart problems, too. These can be problems with an abnormal heart rhythm, infection of the heart, abnormal anatomy of the heart or abnormal blood vessels in the heart. Most of these can also be found with a good family history, a good physical exam and, possibly an EKG. This is not the kind of examination that can be done in an “assembly-line” fashion in a gym full of young athletes. If there is any family history of heart problems, a history of someone in the family who died suddenly at a young age or if a child has ever had fainting during exercise, that child needs at least a full evaluation by their physician and probably a cardiology referral.