prolonged qt interval

[k4mom]

my daughter had 2 ekgs and showed a QT interval of 468 with a heart rate of 68.  Obviously this is a prolonged qt, but what are the odds that it is Long QT syndrome?  If it isn't, what is it????  I can't find any answers. I do know that it is considered a borderline QT interval until it hits 470.  If she doesn't get diagnosed with long qt syndrome (cardiology appointment is next week)  Does it just mean that she has a long qt interval and nothing else?  

[bootielious]

I am 33 am TRYNA SEE IF my ventricular rate is 86 atria rate 86 qrs interval is 74 qt interval is 374 qtc is 447 p axis is 30 R axis is 21 t axis is 21 now is all this normal are should I be alarm

[k4mom]

I don't know if it is corrected or not.  They kept telling me that it was probably nothing and I finally got the number yesterday.  I have been told to just hang on until we see the cardiologist next week.  The waiting is killing me.  She is 12 and very tall and thin.  Almost 6'0 (5'11 1/2") and about 130 lbs.  Her blood pressure is about 88/55 whch is why they thought she may be getting dizzy (height, weight, blood pressure, hormones, etc.).  I have been restricting her from activites (gym, volleyball) even though the doctor said I didn;t have to.  She has never passed out.  She feels dizzy and sometimes her field of vision blacks out with the dizzy spell.  This started about a month ago and she has 5 or more dizzy episodes a day.  Other than that no other symptoms.  Any advice?

[stevie_wonder]

I meant under 60 not 600!!!! haha

[stevie_wonder]

What is the age of your daughter? QTcs of 460 in children under 15 are considered prolonged. 470 is the number used to diagnose Long QT syndrome (LQTS) in males and 480 in females. But there are other things that determine whether someone has LQTS. There is diagnostic criteria by Dr. Schwartz that has been used as a guideline. Just google it and you will certainly find many websites with this criteria. It is based on ECG numbers, T wave morphology, fainting symptoms and family history. A score system is used. But there are also other things like certain medications and electrolyte disturbances that can cause a prolonged qt that can be corrected and is not in fact LQTS. I would stress to your cardiologist that your daughter be seen by an Electrophysiologist who is experienced in LQTS. Most doctors and even cardiologists are not qualified to properly diagnose LQTS. A prolonged QT for any reason needs to be treated, even a borderline one if she does have LQTS, with a Beta blocker at the very least. Some doctors are too quick to dismiss a prolonged QT. My family often has borderline QT intervals but we still have LQTS and still are all on treatment. Just another note: QTs at heart rates near 60 are more accurate than QTs at slower(under 600 or faster (over 90) rates, but her interval still needs to be read manually because machines can be wrong. Was her QT 468 or was her QTc 468?