Familial vasovagal syncope and pseudosyncope: observations in a case with both natural and adopted siblings.

This report describes an 11-year-old girl with recurrent syncope beginning at the age of 2 1/2 years. Her paternal grandmother, father, and three of her five natural siblings had similar symptoms, often linked to emotional upsets. There were three adopted children from a single family, and none of these had syncope. Prior to referral there was an increase in attacks, some with convulsions, but with no other features of epilepsy. Vasovagal syncope was confirmed. However, continuous electroencephalogram, blood pressure, and heart rate recordings during attacks indicated that in some episodes there was neither cardiovascular change nor epileptiform activity, implying feigned syncope (pseudosyncope) with pseudoseizures. A psychological origin was sought, found, and in part rectified. The separation of vasovagal syncope from pseudosyncope, in the context of the family history, is discussed.