ECG variations

[schmadrian]

Recently, as a candidate for medical drug research, I had an ECG come back noting 'left axis deviation'. As a result, I had to have it re-done. Three days later, I went back for the retest; this time it came back as 'left bundle branch block' and I was booted from the study as being 'Not Within Normal Limits'. The results scared me and I went to my physician, who had me go for an ECG 2 weeks after the first. The result was a) sinus rhythm (slow), b) left axis deviation and c) 'Normal ECG'

Here are the specifics:

Test #1 P/PR: 103ms/158 ms, QRS: 104 ms, QT/QTc/QTd: 439ms/435ms, P/QRS/T axis: 16/ -35/94, Heartrate: 59bpm
Test #2 P/PR: 110ms/165 ms, QRS: 157 ms, QT/QTc/QTd: 448ms/478ms, P/QRS/T axis: 46/ 16/177, Heartrate: 77bpm
Test #3 P/PR: 107ms/147 ms, QRS: 106 ms, QT/QTc/QTd: 426ms/428ms, P/QRS/T axis: 39/ -39/64, Heartrate: 61bpm

I am a very fit 47 year old with no personal history of anything heart-related, cholesterol great, BP 120/80 with a 76 year old father post-stroke and heart attack, 73 year old mother w/ bypass and valve replacement.

How can there be such a variance in the three tests...and should I be worried and take a forth?

[devu1234]

A related discussion, ecg variations was started.

[schmadrian]

Thanks for your feedback...but I'm confused.

The ECG my physician had me take came back as 'Normal' (as noted in my query) as interpreted by one of the area's leading cardiologists. My physician's response was 'It looks fine, we cando another in six months, there's nothing to indicate pursuing this further.' And I agree; how many times do you have to confirm a good test result? And as I say, I'm in exemplary health, no symptoms of anything whatever. In fact, I've lost weight this year!

My question really was addressing the variances in the tests, how I can go from a 'bad' ECG to a 'normal' one in less than  two weeks? Input elsewhere suggests that the innacurate placement of the ECG electrode leads can produce a faulty result. That seems to be the case here, with my first two tests.

[Douglas Bogart, MD]

You likely have abnormal electrical activation of your heart.  The left axis deviation may be due to what is call left anterior hemiblock which is delayed electrical conduction in the left bundle branch.
There are two bundle branches (right and left) that carry the electrical current in your heart from the upper   to the lower cardiac chambers and it sounds like you have a problem with the left bundle.  The likely reason that the 2nd ECG showed the left bundle branch block relates to the faster heart rate at the time of this ECG (77).
When the heart rate exceeds a certain limit your conduction system is unable to conduct the electrical impulses  over the left bundle and the ECG manifestation is a left bundle branch block.  You should consult your primary doctor and likely see a cardiologist.