Prolonged QTc for my daughter? EKG attached

[mshanson3121]

My 4.5 year old daughter has a history of congenital heart disease, born with VSD, ASD, both spontaneously healed. Some trivial tricuspid regurgitation. She's always been prone to spells of high heart rate/pounding heart. This spring had a few months where she was getting short of breath with racing/pounding heart with activity (especially climbing stairs). She had an EKG the other day, we're still waiting for results but I did snap a pic of the EKG and jot down some particulars:

Vent rate: 92
PR Interval: 120 ms
QRS duration: 76
QT/QTc: 360/445

I know that for her age, QTc should be under 440, and her QRS is pushing the limits of what's normal (under 80). So what exactly does this mean? And what should be done? Will she need more testing?

As for if there's a history of long QTc... I don't know. There's certainly a family history of dizziness and tachycardia (my grandmother, my cousin, myself), and then my husband's side of the family has a long history of heart disease, including early heart attacks (his uncle dropped of a sudden heart attack at 50, his father had one at 50), and my husband also gets dizzy spells.

[spade22]

IMHO, There is enough medical history here that warrants a work up by an EP.

[mshanson3121]

I got a little more info on family history - both of her great-grandparents on her father's side required pacemakers due to arrythmias. They received them in late 40s/early 50s. There was also a 1st cousin that died of SIDS.

[spade22]

There is  a family history that "could" be indicative of LQTS (faints, sudden death due to an arrhythmia). The best way to move forward is to have your daughter see an EP for a work up and your husband should also see an EP for an EKG.  Her QTc is barely in the borderline region but based on the above I would suggest further workup to be on the safe side.

[itdood]

I meant asymptomatic.  I thought the *specific* symptoms of LQTS were fainting, seizures, and sudden cardiac arrest.

racing heart and breathless are things I've not heard as being related to LQTS, but they can be related to other types of issues.  I guess you read or heard something different.

It sounds like all the evidence for LQTS in your husband's side is anecdotal.  Has anyone tested positive for it?  If not, you can only make assumptions.

[mshanson3121]

Do you mean she's asymptomatic, or symptomatic? I thought racing heart, breathless were signs of LQTS?

I'm honestly not sure what the cause was. For his uncle, I think it was arrythmia. Now, this would be going back a bit, but my husband's  grandmother always had fainting spells, and no one knew why.

[itdood]

From what you said she's asymptomatic for LQT syndrome.  

When you say family history of dropping from a heart attack, what does that mean?  Was it an ischemic attack (blocked blood flow, arteriosclerosis) or was is sudden cardiac death (arrest), from an arrhythmia?

I would seek a second opinion.  A holter monitor for as long as possible wouldn't be a bad idea to get more info.