syncope in teenagers

After a normal ECG and Heart sonogram, could my daughter still have Long QT Syndrome?

[Jeffrey R Boris, M.D.]

Dear Mom,

An echocardiogram is not useful in the confirmation of long QT.  As far as a normal ECG, there is increasing data to show that patients who have normal ECGs but are carriers of the abnormal gene mutation can stilll be symptomatic.  That said, the way that we often know about the gene is because they usually have a sibling who is gene positive, as well.  Thus, it would be important to ensure that there is no other important personal or family history consistent with long QT.  You should review this with your daughter's cardiologist.