UKC

I'm reading my Big Book of ECG interpritation again after last reading it a few years ago. There was one thing that I could not get my furry brain around then and I still can not grasp it now.

How can you spot and interpret axis deviation either to the left or right?

In reply to Temp Lemming:
They will find you, you know


Edit:
Ha! Looks like they already have!

In reply to JJL:

Yep. Proves my point in the other thread quite well.

I'm having problems logging in normally so as a temporary measure I've created a similar pseudo.

Hopefully somebody will be able to genuinely answer my question.

Cheers

In reply to Temp Lemming:
? Yes the site seems a bit broken at the moment.

By "left to right", do you mean the time axis. Presummeably, this translates to spotting an irregular hearbeat - jitter, if you're an electronics engineer.


Hmmm, no spelling chqeur either !

In reply to Temp Lemming:

I had an ECG as part of my over 40 health check my GP invited me to attend. My ECG was fine but I guess it's a visual thing. You are looking for a compression or expansion of the heart beat wave to indicate an irregular rhythm or abnormally high or low heart rate.

In reply to Hairy Pete:



I think it has more to do with the electrical pathway of the bundle of his and the bundle branches.

I just can't get my furry little brain around spotting the axis deviation. I can spot the basics like ST elevation, rbbb and lbbb but this deviation stuff Blow's my furry mind.

In reply to Lemming:

Incidentally, it's not me!

In reply to Temp Lemming:

Do you visualise these things or try and work them out? Personally I visualise or use pattern recognition because I'm not great at vectors and sums...

Think of them as like contour lines on a map from an early survey attempt... Maybe of a fairly complex peak with some outliers - like Liathach or Kanchenjunga

On all the photos of the hill, peak I is way over on the left, II in about the middle, and III the peak over to the right.
As long as the main summit is somewhere in the middle of the massif you are happy.

You get the data in from the surveyors. If they reckon I is actually a pothole and III is the main peak, that's not not what you expect... way too far to the right, so RAD. (I is negative, III is positive)

If I is the main peak and III appears to be a pothole, the main peak is way off to the left where it shouldn't be... LAD. (I is positive, III is negative)

So if I and II are positive you're probably OK. Ideally II is the highest. Normal axis.

Hope this helps rather than confuses!

b

In reply to Temp Lemming:

I'm not entirely sure what you are after but these are from my notes (abridged version....)

left heart axis - QRS in lead I is positive and negative in 2 and AVF (range -30 to -90 degrees)
right heart axis - when lead I is negative and AVF positive. (range +90 to +180)

any good?

In reply to Temp Lemming:

Imagine a clock face: draw lines at 3 and 6 o'clock. 3 o'clock is termed 0 degrees.
ECG trace I runs along 3 o'clock, aVF runs along 6 o'clock. If the QRS is positive in I, draw a line as long in mm as the QRS along 3 o'clock, if it's negative, draw it along 9 o'clock. If the QRS in aVF is positive draw another line as long as it along 6 o'clock, if negative, draw it along 12 o'clock. The axis now runs between these 2 lines, if you want and know how, you can use vectors to find exactly where, but a rule of thumb is that if will be closer to the longer line
Normal axis is between minus 30 degrees and plus 90, where zero is 3 o'clock. LAD is between 12 o'clock and 2, RAD is from 6 and 9, further away, in the 9 to 12 o'clock quadrant, is deemed far LAD or RAD.

There are other methods which use quick looks at different leads, these and the above are explained in more detail here:
http://lifeinthefastlane.com/ecg-library/basics/axis/

Ps, we always thought that The ECG Made Easy, should have been more accurately named The ECG Made Marginally Less Complicated, But You Still Won't Understand It All. Not quite so snappy though.

In reply to damowilk:

>


Yep, that's the book I have. Ignoring the axis deviation still let's me get a flavour of what's in front of me. I just want a bit more understanding.

I've spotted the odd wankieback too.

In reply to Temp Lemming:

One of the few clinical relevances of the axis I can recall, is that if there is RBBB and axis deviation, the patients most likely has bifasicular block, throw in 1st or 2nd degree AV block and its trifasic and only a short step to complete heart block. Cardiologists usually want to know about any trifasic block, and bifasicular with symptoms. This is, as always, an over simplification, but generally serves well to non-cardiologists.

In reply to Temp Lemming:

And there's my hypothesis that people just look at the automated diagnosis notes at the top of the wiggly lines blown completely out of the water....

Or am I actually right and a few people have a higher standard?

In reply to pneame:
Rarely worth looking at IMHO. Often complete rubbish. I actually prefer the machines that don't have the auto-diagnosis, I'd trade for an old ECG any day.