by appleapple

I understand that " ST segment elevation that present in two or more anatomically contiguous leads indicates MI", but I could not figure out: why is that so? what is the eletrical activity that is happening in ventricle makes ST segment elevated? Thanks for your help!

Re: Questions about ST elevation

st elevation is caused by delayed/altered conduction through dying or 02 deprived tissue (the part of the heart that is dying). That’s what the EKG is picking up.

Re: Questions about ST elevation

Many of you know that I have an extensive cardiac history and am under the close supervision of a cardiologist. This thread got me to thinking. Last spring I had some cardiac testing including a treadmill stress test. I did ok but could not finish due to extreme fatigue and shortness of breath. I think I came within just a few minutes of completion and I had to sit down or pass out! After I was sitting, they observed me (still on the cardiac monitors) for almost an hour before they would let me leave. The nurses said I was having elevated ST waves for almost 30 minutes. They kept asking me if I was having any pain, etc. They called the cardiologist on call (not my regular doc) and he came in, looked at the monitor a few minutes, whispered to the nurses and left again. When the nurses unhooked me and let me go home later they said my heart rhythm was now normal and I was to call my cardiologist later if I had pain, SOB, etc. I left thinking my rhythm abnormality was not that serious.
Ok, I know I should know something about cardiac rhythms or at least educate myself as I have to deal with this on a personal level. In my defense, I have been an OB nurse for a loooonnnnngggg time. I am thinking that these cardiac nurses assumed that as I nurse I would know and understand without the teaching. Thankfully,
my cardiologist got the test results and immediately brought me back to the hospital to have a cardiac cath and stent placement for another 98% blockage.
The point of all this, I guess, is to stress 2 points:
a) please make sure your patients understand the discharge instructions given especially if you are dealing with other health care professionals.
b) as a patient and a health care professional, we must take the responsiblity to educate ourselves about our specific problems so these kinds of potentially life threatening misunderstandings don't happen.


Just my

Re: Questions about ST elevation

Originally Posted by nurturing_angel

Many of you know that I have an extensive cardiac history and am under the close supervision of a cardiologist. This thread got me to thinking. Last spring I had some cardiac testing including a treadmill stress test. I did ok but could not finish due to extreme fatigue and shortness of breath. I think I came within just a few minutes of completion and I had to sit down or pass out! After I was sitting, they observed me (still on the cardiac monitors) for almost an hour before they would let me leave. The nurses said I was having elevated ST waves for almost 30 minutes. They kept asking me if I was having any pain, etc. They called the cardiologist on call (not my regular doc) and he came in, looked at the monitor a few minutes, whispered to the nurses and left again. When the nurses unhooked me and let me go home later they said my heart rhythm was now normal and I was to call my cardiologist later if I had pain, SOB, etc. I left thinking my rhythm abnormality was not that serious.
Ok, I know I should know something about cardiac rhythms or at least educate myself as I have to deal with this on a personal level. In my defense, I have been an OB nurse for a loooonnnnngggg time. I am thinking that these cardiac nurses assumed that as I nurse I would know and understand without the teaching. Thankfully,
my cardiologist got the test results and immediately brought me back to the hospital to have a cardiac cath and stent placement for another 98% blockage.
The point of all this, I guess, is to stress 2 points:
a) please make sure your patients understand the discharge instructions given especially if you are dealing with other health care professionals.
b) as a patient and a health care professional, we must take the responsiblity to educate ourselves about our specific problems so these kinds of potentially life threatening misunderstandings don't happen.


Just my

Wonderful point! When you specialize in nursing you focus on your specialty and become an expert in that field. That means all the other specialty things you learned way back in school was fluff, and not as important to remember. As a critical care nurse of adults I can not competently care for anything smaller than 4ft. When I had my first baby the nurses did minimal training so I could care for my newborn-the reason...I'm a nurse so I must know everything there is to know .
Even when I had a cardiac event that required stress-testing and cath the nurses assumed I knew everything to ask and do to take care of myself at home. Hey-I don't care if it is my specialty...this is ME and I can't think objectively when I'm on the receiving end of care. You bet you bon-bons I asked questions...even though I knew my co workers may "think I didn't know something"--I didn't care. I do know--when its not ME. It is ssoooo improtant to never assume someone knows something based on their background. Because of my experience I make sure I explain care/procedures/whatever to all patients--even the doctors I've cared for

Re: Questions about ST elevation

Originally Posted by appleapple

I understand that " ST segment elevation that present in two or more anatomically contiguous leads indicates MI", but I could not figure out: why is that so? what is the eletrical activity that is happening in ventricle makes ST segment elevated? Thanks for your help!

Ischemic cardiac tissue causes a localized extracellular shift in K+. This creates an altered conduction gradient that essentially lowers the EKG baseline by sending out a detectable 'injury current'. When the ventricles repolarize, they are repolarize back to 0-- which appears elevated next to the depressed baseline due to injury.

This is why prior to ST elevation you may detect hyperacute T waves--tall, peaked T waves from localized K+ leaking.