I can understand your worry. My youngest son was about 9 when we were first "introduced" to LQTS.
ECGs can give false positive QT intervals. The numbers are really just a guide and shouldn't be used unless the QT interval is hand-measured by an experienced Electrophysiologist (heart rhythm specialist). Pediatric cardiologists are not always experienced enough to diagnose LQTS.
People with LQTS often have seizures with their episodes and can even be misdiagnosed as having epilepsy.
QT intervals change often in people affected by LQTS. Mine for example can range anywhere from 460 to well over 600. QT intervals can even vary among the different leads on the ECG so that it why it is so important to have an Electrophysiologist read the ECGs.
Borderline for children is around 450. A QTc of 480 and 490 is considered prolonged in the world of LQTS. Some doctors will not consider a QT interval prolonged if it is under 500 and some doctors have absolutely no idea what a prolonged QT is. Trust me, my family physician was one of the them! So I wouldn't take what a general physician or even a cardiologist says as the gospel truth regarding LQTS. It is a difficult disease to diagnose and even specialists find it tricky at times. But if your son's ECG does show a prolonged QT interval on more than one occasion this will help with the diagnosis process.
Even exercise stress testing can give inconclusive results. There are now 12 different known types of LQTS and some types give different results on the stress test. And it also depends on who is interpreting the results.
If your son does have a prolonged QT and his faint and seizure were from this, he should be put on medication soon. I would recommend that you contact SADS (www.sads.org) and find an experienced doctor in your area to review his ECGs. Or if you want, you can send me a private message and I can give you 3 world renowned LQTS doctors email addresses for you to send a scanned copy of his ECGs. They review them for free and advise you on whether they suspect LQTS. They might even consider contacting your doctor. They are great people and are dedicated to helping people get diagnosed or better yet, cleared!
There is also a very active Yahoo group for Long QT http://health.groups.yahoo.com/group/longqt/
Also, there is a chance that your son had a case of acquired LQTS. There are many causes of acquired LQTS and most often once the cause is found it can be corrected. Electrolyte imbalances is a common cause, medications is another one. Hypothyroidism in rare instances can cause a prolonged QT but I would think your son would be very sick from this and wouldn't be active.
I have probably bombarded you with enough info and I don't mean to scare you but I just want to make sure that you take this info and continue searching the internet for more info until you are 100% confident with what the doctors are telling you.
Hypothyroidism isn't going to cause LQTS, however hypocalcemia can lengthen it. Usually there is a family history of LQTS, do any of your family has this problem? Have there been any sudden deaths in your family with young members? His size being on the small side is NOT indicative of hypothyroidism either, it would actually be the opposite, with hyPERthyroidism, he would tend to have a hard time gaining weight. In 1-4% of children there is an increase in the QT Interval, even though they do not have LQTS. It would be important to have a Holter Monitor put on your son as LQTS tends to show up best during sleep. A Stress Test would also show a pronounced LQTS and especially at the point of about 2 minutes after the recovery period starts. LQTS is a serious problem to have to deal with and with him being active in sports, that would have to be stopped for his own good; that isn't going to set well with him so you may have to look into some forms of activities that he can like to do. For your support there is also a Pediatric Cardiology Forum here on Medhelp; feel free to visit that forum as well. take care
Thank you very much for your feedback.
It has been an exhausting few days. It does feel like a rapid ''introduction'' in to a parallel workd right now.
Firstly we are booked in for an echo cardiogram next Wednesday for further analysis of his heart. His scans have been forwarded to a consultant cardiologist (Electrophysiologist??) in Liverpool (uk) for assessment before anything else can be done. As there is now an emailed version of his trace I will ask for a copy of it and yes I will contact you with regard to email addresses of Doctors if that would be OK?
With regard to the seizure, in my mind it was directly related to the bang on the head. It happened within two minutes of the bump and the area around his temple was grey for a couple of days afterwards.
To our mind he has never had a dizzy spell, never had pain in his chest, felt feint or passed out - he nas never complained of feeling un well etc. We are considering everything he has ever done in his 6 years to be able to apply some logic here too!
Two years ago he fell off some monkey bars at our local park. He hit the deck flat on his chest and the air expelled from his lungs rappidly to the point of making an awful squeaking sound. He went blue in the lips and generally lost all colour but recovered well with minimal medical intervention. (his heart was clearly able to cope with the shock of a 5ft+ fall etc.)
He has never passed out or feinted before. As far as I am aware he has never even complained of feeling dizzy! There is no incidence as we are aware of LQTS in the family - I was tested last year as part of a charity screening and everything was fine with the ECG (I do realise now though that the ecg in itself is not the most accurate form of diagnosis but surely it does it's job in highlighting areas of concern...) My partner has also hade Egc screening in the past and again, nothing has ever come back a cause for concern - I don't know though is it like a blood test where they have to be looking directly for something or would it be picked up on a very general screening?? I suppose really it would depend on the person interpreting the results!
I am 35 and my partner is 58 and we have both lived physically active lives again, with no history of seizures, passing out or feinting.
With regard to early deaths/drowning my fathers uncles son (my fathers cousin) drowned as a child after falling out of a boat - two children fell out of a boat and only one was recovered in time before he drowned - that was 35 years ago and the only incidence of any one drowning. There have been no other incidences of unexplained early deaths.
I am clearly struggling right now with the idea that this could be a life sentance. I am trying to keep a perspective and am grateful for your advice on other causes/aquired LQTC etc. Everything I have read so far seems so definative - (apart from the interpretation of the scores etc!!) I do appreciate that should he end up with a dignosis of LQTS, there is support in place etc. There are also many other conditions that children (and adults) deal with on a daily basis that are far worse but.. It's the idea that at 6, his life is compromised and different choices have to be made. I'm already grieving for a life he might not be able to live if that makes sense.
Anyway to keep things in perspective... We are hoping to hear from Liverpool tomorrow or Monday and we have to take it from there - maybe request a holter monitor if one isn't asked for on our behalf.
Thanks again for your time.
Thanks you for your feed back regarding the hypo and hyper thyroidism.
I have asked for his thyroid to be screened. I too would expect him to have hyperthyroidism but I was very similar to him as a child in terms of build etc. and went on to have a hypo diagnosis. My mother has a hyper so it would fit if it went alternately.
Without doubt he is smaller than either of the other two children I have and his father has two adult children who were 'normal' sized as children. It is always assumed that he has his fathers build as his father is small too. I think now though maybe it could be to do with something else.
When he was a baby he had to see the paeds because he was borderline 'failing to thrive' he struggled to put any weight on to the point where he had extra calories in his diet and now has two bad teeth. They tested him for pretty much everything at that point including CF. Everything came back negative and now I'm feeling that maybe something was missed then.
Better late than never it might be but I need to have confidence in the system now to accurately diagnose what is going on. It is difficult when there are no definitives.
Thanks again for your insights in to thyroid issues -
I can't have enough information at the moment and clearly, if he needs to give up sport he needs to give up sport - with two younger brothers that's going to be very hard though!!
There is always commentating I suppose!
I can certainly understand how you feel. My daughter was diagnosed with heart disease at 6 years of age as well. It robbed her of her childhood, of her teen years and all but one of her friends. She finally received a new heart when she was 22. Keep good thoughts and hopefully this is not a LQTS diagnosis for your little one. I wish you only the best. Again, you are welcome to come over to the Pediatric Cardiology Forum here on MedHelp. This forum is really designed to deal with adult issues; the other forum is for the families who are dealing with heart diseases in their children. Take care