explain sinus tachy please

[bbxx]

I am trying to understand things. I thought sinus tachy was when your heart is going fast from anxiety or exercise etc... a normal thing? Yet I have heard more than once people say they had ablation or going to for sinus tachy.
I guess I dont understand, can anyone please clarify?

[is_something_wrong]

Yes, we didn't need to hurry, he got an appointment later this day :)

[bbxx]

hope your dad is better. :)

[is_something_wrong]

Now we agree ;)

It all should depend on the start and stop of the tachycardia. If I'm not mistaken, sinus tachycardia is defined as a supraventricular tachycardia even at rate 101, and even a heart rate of 101 is abnormal if it doesn't have a cause. I wouldn't be happy if my RHR at 08.00 AM was above 100. Today it was 46, that's pr definition outside normal range. I know the cause is a high stroke volume (I have an EF in the high 70s) and it's asymptomatic, so it doesn't bother me. As I'm writing this, my heart rate is 68. I'm at work and I just got noticed that I need to drive my dad to the ER because he's got some infection from the surgery he did a couple of weeks ago. A little stressed, and my HR responds as it's supposed to do.

I know an EKG can't differ the tachycardias at high heart rate, if the P wave is buried in the T wave, and from what I know that should happen at rates above 150-170, that's possibly the reason?

I would say that is a tachycardia warms up slowly, varies with inspiration/expiration, or changes with body positions it's most often a sinus tachycardia. I have a "problem" with sinus tachycardia if my BP is too low (I'm dehydrated, after exercise or sitting in a warm room). Heavy meals may also increase my HR to a certain degree.

[RNRita]

People have lived with SVT for years and it has gone on for hours, but remember, in the grand scheme of things, ablation is relatively new.  A lot of those people went to the ER for conversion of some type.  Another thing we used to do on the unit (and I watched the cardios actually TEACH this to patients) was carotid massage. (Don't do this without instruction from a trained professional.)

I used to have a resting HR of 96, at times.  It felt uncomfortable to me.  That is when I went on atenolol.  They started me on 75 mg (way too high) and my heart rate went down to 47 that evening......my husband wanted to take me to the hospital, but I said, "No, this feels too good."  LOL

[bbxx]

the other thing I thought was---if someone normally has a resting rate of 60, then say their rate is 90 all day--that is  a big jump compared to someone whos resting rate is 80 and is 90 all day. Normal sinus rythm is 60-100 or some say 60-90. Then again most people dont have a clue what their resting rate is (unless they exercise) because they dont have feel anything.

[bbxx]

I guess what confuses me is that people will live with svt for years and years and I have read they can have that high heart rate for hours and not kill them?

[RNRita]

Oh and so as not to confuse, you can have heart rates over 150 that come from anxiety or exercise and they do NOT ablate for that.  I am speaking about HR that go over 200 spontaneously, or a sinus tachy rhythm that is constant and affecting normal life, however, first line is usually beta blockers or calcium channel blockers.

As for labeling by rates, the above is how it is done.  Anything over 151 is not called ST anymore, however, it is ONLY a classification and everything else we do agree on, for the most part.

[bbxx]

thank you guys. :)

[RNRita]

Normal heart rate - 60 - 100,   tachycardia 101 - 150, supraventricular tachycardia 151-250.  This is the medical def of each.  I did not want to get into an explanation of any EKG changes, however, ANY heart rate over 150 IS, in fact, classified as SVT (until it reaches 251). Calling it SVT just means it is originating from above the ventricles.  The morphology may be that of a normal P wave, QRS complex, etc, which is why the doc might have mistakenly called it sinus tach.  So, when I say you can have an ablation for SVT, this is correct and happens often.  I am not saying ablate sinus tach because these are rates under 150 and not considered dangerous, by any means.
I saw many ablations for this while on the CCU, and actually, a friend of mine had a very successful one for SVT.  It changed her life.

[is_something_wrong]

Sorry, I disagree a bit here ;)

Sinus tachycardia can easily be higher than 150. I was exercising yesterday, and I had sinus tachycardia at rate 190 :) But if you get a tachyarrhythmia above 150 at rest, without feeling anxious, yes, the cause is usually something else.

Panic attacks can drive the heart rate far above 150, for example, once I panicked during exercise and my heart rate peaked at 220. My cardiologist told me that heart rates like this in the setting of anxiety and often a little low blood pressure is not unusual and not a sign of any arrhythmia.

bbxx;
You can't ablate sinus tachycardia, as it's not a disease, it's a normal response to "something" and if needed, this "something" can be treated, often it's anxiety, fever, hyperthyreoid, low blood pressure, dehydration, etc. However, some people with inappropriate (chronic) sinus tachycardia (which means the heart rate is never below 100) an ablation can be done. They can try to modify the sinus node to make it less vulnerable to autonomic affection, or they can destroy the sinus node completely and install a pacemaker.

[RNRita]

Sinus tachycardia is any rate over 100 to 150 bpm.  It doesn't matter what it is from.  However, rates over 150 is called SVT or supraventricular tachycardia. When people get ablations, it is usually due to either of these affecting their lives. For instance, anxiety can cause a heart to be tachy for a bit.  No big deal.  Rates over 150 for a lengthy period can start to cause big problems, so usually one must go to the ER to get converted back to original rate.  

A lot of these fast rhythms can start from irritable cells in the heart (like PVCs and such do) and come for no reason, ie...you bend over and wham.  After a certain number of times where this is happening, interrupting your life...you go for the ablation!