Can a EKG be wrong?

[Maria]

Dear Doctor,
I went to the ER on 18 Oct. with chest pains, shortness of breath, nausea, shakes and sweating and I was given an epi and oxygen right away.  I suffer from hypertension and vocal cord dysfunction.  Afterwards, they did an EKG and hooked me up to a heart monitor.  The EKG was normal but during the attack the doc kept asking me if I ever had a heart attack before?  I haven't.  I see my regular doc next Monday and was wondering what kind of tests should I ask about and is it possible that the EKG can be wrong?  I have a strong family history of heart disease (MI's,stroke,hypertension,diabetes)and I feel like I might have had a mild attack.  Since the 18th, I have had off and on chest pains, some mild nausea and swelling in my hands and ankles.  My blood pressure meds include 100mg tenormin and 40mg of zestril daily.  Also, do you recommend a baby aspirin to take daily?  I'm trying to research some sites on women and heart attacks and I want to ask the right questions next Monday to my doctor.  Thank you for your advice and assistance.  This is a great service.  Keep up the good work.

[dwigman]

A related discussion, EKG reading was started.

[Cleveland Clinic, MD]

Thanks for your comments.  It's true to not trust the computer - after all it is only a computer.  The variation in reading by cardiologists is probably only in minor items and not major ones.

[John Mountain]

A general comment on reading EKG's.  Never trust the computer
analysis of an EKG.  These are supposed to be for screening
purposes only.  I used to work as a programmer for a company
that wrote a program to analyze EKG's.  I did a study where
100 EKG's each with significant pathology were analyzed by this
computer program, and also by 7 different real cardiologists.
There was a wide spread of interpretation on many of the 100
EKG's.  The computer program ranked about fourth in overall
accuracy, that is, more accurate than about half of the
cardiologists.  The absolute standard for each EKG was defined
as the consensus interpretation.  

Another scary fact I read about is that the same cardiologist
may read the same EKG differently after a period of several
months during which he forgets that he has seen it before.

Rule : always get a second opinion if you have any doubts.

[Cleveland Clinic, MD]

A example of the ECG beingly "falsely negative"

[Sherri]

Didnt mean to post that twice......Sorry!!!

[Sherri]

My father went to ER with mild chest,sweating and shortness of breath...EKG was normal and first set of cardiac enzymes were normal. ER Dr. wanted to send him home but thank God is Medical Dr. wanted him to stay and have a stress test the next morning...Before they could even do the stress test..cardiac enzymes (2nd)set were elevated so they opted for resting part of stress test where they just look at the heart...Dad had to have immediate catherization and they found his aortic valve was leaking severely...and he had three bypasses..He also had an EEG to determine how badly the valve was leaking...He did have open heart surgery...three bypasses and the valve replaced...His only symptoms before heart attack was fatique and shortness of breath...which they attributed to the leaking valve, I know all of this is very frightening but I just wanted to share with you my experience....I would insist on more tests...Dad is doing great now....Good Luck to you.......

[Sherri]

My father went to ER with mild chest,sweating and shortness of breath...EKG was normal and first set of cardiac enzymes were normal. ER Dr. wanted to send him home but thank God is Medical Dr. wanted him to stay and have a stress test the next morning...Before they could even do the stress test..cardiac enzymes (2nd)set were elevated so they opted for resting part of stress test where they just look at the heart...Dad had to have immediate catherization and they found his aortic valve was leaking severely...and he had three bypasses..He also had an EEG to determine how badly the valve was leaking...He did have open heart surgery...three bypasses and the valve replaced...His only symptoms before heart attack was fatique and shortness of breath...which they attributed to the leaking valve..Not meant to frighten you just think you should insist on more tests...Good luck....

[Cleveland Clinic, MD]

As with all tests there can be "false-positive and False-negative" findings on an ECG.  An echocardiogram will help to verify or exclude the presence of damage from a heart attack.