Racing heart rate and LQTS??

[sabrina]

Hi,
I don't know where to begin! It all started in Gr.8, I was 14 at that time. I experienced skip beats out of the blue(not sure whether they were PACs or PVcs). Are PVCs more dangerous? The skip beats lasted for a few days and I have never experienced the same type of feeling ever again. Now the funny feelings I get are in my chest and in my neck. I dont know whether these are PVCs or PACs? How do people describe these feelings?
About 2yrs ago I had this really fast and irregular rhythm that came out of the blue too. It lasted for a few seconds and then came back.These short episodes lasted for a
about 45 mins. I am wondering what this rhythm was? A-fib, torsades? hasnt come back and the doctors couldnt catch it!

I had a holter and the report said "intermittent variation in the repolarization phase of the ecg" what does this mean?Anything to do with LQTS?Then about a year ago, I was at the movies when all of a sudden I got short of breathe and my heart was racing, I felt extremely lightheaded. These episodes happen every few months. They say its sinus tachycardia but they have only caught it once and at that time it wasnt going that fast and I wasnt feeling lightheaded! What is this??I have also nearly fainted after exercise and I am scared that it is LQTS!
Is racing heart rate a sign of LQTS? Is it a ventricular or atrial arrhythmia that causes the racing in LQTS?What are the signs and symptoms of torsades? Can TdP last for only a few seconds?irregular or regular?
My QTc with 88bpm is 415
            110bpm is 436 shouldnt the QTc decrease as the HR increases?

[sabrina]

Where did you disappear to Hank???

[sabrina]

hey......why haven't you got back to me?

[sabrina]

Hi,

I read that posting but that is unrelated to my situation. That was regarding Inappropriate sinus tachycardia (IST). I don't have that and the scarey thing is is that my heart rate goes up to 180 bpm!! Its crazy!! I dont know if this could be sinus tachycardia or ventricular tachycardia??

How high can IST make the heart go till? 140 bpm max, I think

And at times my heart rates goes really slow, like 50-60 bpm!!
I dont know why

Could I be having sinus node dysfunction??

As one exercises, PVCs decrease in a normal heart, but when I exercise my PVCs increase and thats a bad sign right?

[sabrina]

Thanks for your help.  but that comment that I had written regarding the fast heart rate causing damage in a short time was answered by a doctor-Reply by: CCF CARDIO MD - CRC on 2/5/2001
So isnt it true, then?

[sabrina]

A rapid tachycardia, even for just a short time, can cause damage to the heart. I read this statement in another forum, is it true? How long does the tachycardia have to occur until it causes damage to the heart?
Thanks

[sabrina]

I am borderline, but many people with LQTS are borderline like me and this is not a good sign.  I can die at any time too!! My case is actually worse because I am symptomatic....I am terrified

[sabrina]

Why haven't you got back to me?

[sabrina]

When you say being scared is the worst thing for LQTS, do you mean that it can make the LQTS worse, cause symptoms?? Now you how dangerous and life threatening my situation is and agree taht I defintely have LQTS!!! Is it under the age of 50, where if sudden death occurs it is due to LQTS??
Thanks

[sabrina]

Hi,

I have to worry because my QTc is borderline prolonged and they said that 20-40% of individuals with LQTS have borderline prolonged QTc intervals...and the reason why im scared is that Ive near fainted during exercise 2-3 times!!!!This is a clasisc sign of LQTS...and yes, my uncle suddenly passed away at the age of 47 in his sleep (they are suspecting that it was LQTS). My brother also fainted when he was 9 yrs old......I have every right to be terrified!!!
talk to you soon

[sabrina]

Hi,

I most probably do have LQTS because my QTc is greater that.420
It is usually 430-440. Of the 5% PVCs that are dangerous, I probably fall within that 5%. Read this article:

Before the molecular breakthroughs in LQTS, a QTc of [is greater than or equal to] 440 ms was considered prolonged.[6,7] In 1992, Vincent et al[8] examined the QTc distribution in 3 families that were genotyped for the chromosome 11p15.5 locus for LQTS (LQT1). Having categorized each patient as a carrier or noncarrier of this LQTS locus, this study demonstrated substantial patient misclassification on the basis of the QTc cutoff value of 440 ms. These results led to the present practice of assigning a QTc of [is greater than or equal to] 460 ms as prolonged and a QTc between 420 ms and 460 ms as borderline or equivocal.[3]

[sabrina]

Hey.....I wanted wirte back to you but its wouldnt let me post a comment......why did my questions disappear? Strange

[sabrina]

Hey,

I looked under the archives "arrhythmia" but your comment isnt there!! Please get back to me asap!
Thanks

[CCF-M.D.-CRC]

Dear Sabrina,
Long QT syndrome (LQTS) is a genetic condition that can be diagnosed from a resting ECG.  Corrected QT intervals are the best measurement for this purpose and they should be done by hand and not the ECG computer.  The T-waves are abnormal and have a characteristic appearance.  If you do not have a family history of sudden death the diagnosis of LQTS is less likely.  

The fast heart rate from LQTS is due to ventricular tachycardia.  Torsades de pointes is a fast, regular ventricular tachycardia that usually last for much longer than seconds.  The only way to diagnosis any arrythmia for sure is to obtain a heart tracing during the episode.  An arrhythmia or event monitor is very good for this purpose.  QT intervals correctly measured usually do decrease during exercise but an increase is not diagnostic of LQTS.