An echo test uses ultra sound and appropriate for wall dimensions (estimates...probably a margin of error of 10%) and degree of viability of heart walls (some impairment... hypokinesis, dead cells...akinesis) and accurate. ST wave interval (EKG tracing) is not associated with an echo other than an elevated ST wave can cause hypokinesis and/or akinesis. False negative regarding heart wall dimensions and viability to probably nil, an EKG specificity is about 30% for elevated ST.
My primary care doctor preferred we take an intermediate step, a stress echo test, before jumping to nuclear/ct based tests. The stress echo came back dead cold normal after 10+ minutes on the treadmill. No changes in ST, not a single change or finding.
The cardiologist feels that no further testing is necessary, that since I am a relatively young person with atypical symptoms and no risk factors, we are done. I must say that the experience has me still concerned. What do we know about the accuracy of the stress echo test...i.e. what is it's false negative profile?
Elevated ST segments are strong indicators of a heart attack in patients with symptoms and other indicators. An EKG is not a very reliable source, if I remember correctly the sensitivity rating is 30% and a correct dx requires supporting evidence from other test, history and symptoms (you are asymptomatic and no history).
ST elevation during exercise testing suggests extremely tight coronary artery stenosis or spasm (transmural ischemia), but ST segment elevation has numerous possible causes. It may be a variant of normal or be due to cardiac or non-cardiac disease. It could suggest that an artery to the heart is blocked and that the full thickness of the heart muscle is damaged.
When physicians recommend a stress test, they are usually referring to an exercise electrocardiogram (EKG). Apparently, your strss test measured the heart's electrical activity before, during and after exercise. However, technically speaking, a stress test is any test that is performed in conjunction with exercise. So, a nuclear stress test usually refers to stress testing that is performed in combination with a nuclear imaging test, such as SPECT scan or a PET scan. In general, a nuclear stress test is more accurate and provides more information than a standard exercise EKG. However, these tests do have drawbacks. They are more expensive and require more time, and there is exposure to a small amount of radioactive substances.
An echocardiogram would provide evidence of any heart muscle damage and wall dimensions, but the most probable cause is coronary artery stenosis (narrowing), and that diagnosis may require angioplasty preferably with ultra sound, or imaging technology.
Thanks for your response. I definitely dont want to mess around with this. I just want to know if there is another test that will yield the same diagnostic evidence, but without the high radiation. I.E. stress echo, or cardiac MRI, PET, EBT, etc. thanks!
Did the doctor or health professional tell you how many mm's the elevated ST wave climbed? Also, did you request a copy of the procedure report?
I understand your concern very well. I've had a number of stress tests as well as at least five Angiograms, plus a pacemaker inserted. I should glow in the dark. Given your age, you are smart to think about these issues. I'm much, much older than you, so I'll qualify my response with that caveat.
An elevated ST wave of 2 mm's or more could indicate a number of heart issues. It's a marker for me that I had serious heart blockages, and nuclear stress tests have led to eight stents. Given your concern, I'd make sure I have a copy of the procedure report. If you have questions, post it on this site, there are very educated people here who can interpret them. I personally think the radiation level is low enough that the risk factor is minor, but that is a personal issue, but believe me, if you have a heart issue starting, you will want to get on top of it asap. In my opinion, heart health trumps these radiation concerns. It's a great question, keep us informed.