[quote Bunnyfuller]@sashh
An ecg does not look at heart structure, it looks at a heartbeat. It tracks the movement of electricity around the heart, and checks that the path the electricity takes, and the timings are correct. As the electricity move through the heart, it triggers the contractions which pump the blood around.
Scans can look at structure, and an angiogram looks at the movement of blood through the coronary arteries.
Not sure why you think something measuring electrical pulses can read structure![/quote]
If we are going down the strictly technical route it actually shows the depolorisation of the cells that causes the electrical wave (myocytes). If you like I could go into detail about the sodium potassium pump but lets keep this technical not very technical.
In WPW the delta wave shows depolorisation of cells in the bundle of Kent, a structure not found in normal cardiac anatomy and one that isn't normally seen on echo.
In cardiac tamponade you can have a completely normal ECG but your heart is not actually beating at all.
This is also why you see changes in T waves, the ECG is showing you what is on the other side of a damaged heart.
I agree an echo is better at looking at the gross structure, but if you can read an ECG you call tell where a myocardial infarction is happening and therefore which coronary artery is blocked.
If a patient has not had access to a clot bluster you can track the timings of the damage to the myocardium (yes I'm old enough to have learned to read an ECG).
Bundle branch blocks indicate the area of the electrical system not working correctly, it can be an end point of a stress test.
Other end points of stress tests include certain changes to P-R interval, this shows that not enough oxygen is getting tot he coronary arteries.
Other things you ca read from an ECG are whether the heart is enlarged, all of it, or part of it.
I suppose the most important thing about the structure you can see is when the ventricles are fibrillating, because, you know, then you can use a defib.
Now would you like a lesson on the history of the ECG, why it's called an EKG in America? Eindhoven's triangle? The difference between 'V' lead and 'C' leads? How to calibrate and ECG machine? How to measure the axis and what an axis deviation is? How about hemi blocks? Piggyback transplants and how you can tell which it the donor ventricles?
Oh and in angiograms, there is always someone monitoring the ECG to alert the Dr to what is going on while they inject dye in to the coronary arteries and the left ventricle.
I'm not sure why you needed to be quite so patronising? The OP is anxious about having to be half naked for a procedure, I'm sure she really doesn't care about who has more knowledge about reading the bloody thing.