12 lead ECG and ambulatory(3 lead) ECG

I have trained a convolutional nerual network using ambulatory ECG (3 lead) readings after filtering. Now I want to augment the data set with publicly available ECG data. I have phsyionet dataset from the follwoing:

• https://physionet.org/content/macecgdb/1.0.0/

Now when I retrieve the signals it gives a 4000*4 matrix containing ECG data. I am not sure which lead in 12 lead ECG would be closer to ambulatory ECG? Out of these 4 coloums, which one should I use to train my model so that it is comparable to 3-lead ECG.

Answer 1

[Star Strider]

I have not looked at the data, however I doubt that a 4-column matrix could be a 12-lead EKG. It most likely represents a vector of sampling times and the offset data.

Looking at the patch location image, the 90° offset would be analogous to standard Lead I, the 45° offset Lead II, and the 0° offset .

[FSK]

Thank you for your promt answer. I have attached the signals and when I plot it, it gives 4 ECG waveforms on the plot. Which one would be comparable to ambulatory ECG? such that a neural network cannot differentiate whether it is from A-ECG or from a specific lead of 12-lead ECG?

I mean in A ECG I only got a stream of scalar values from a sensor which I converted into ADC and then filtered and then trained the model using its scalograms. Now to augment the data, I want scalograms of other ECG signals. But in 12 lead ECG, which lead signals to use?

[Star Strider]

My pleasure!

‘Which one would be comparable to ambulatory ECG?’

I have no idea what you are asking. You will need to make that determination.

[FSK]

My apologies if I was not clear before.

As different leads of 12-lead ECG give a different 'view' of the heart, which one of the leads reading is most closer in values and shape of the graph to that of A-ECG? I hope the question makes any sense?

[Star Strider]

No worries! Many of these concepts are not easy to put into words.

I am not certain what ‘A-ECG’ refers to. My original Answer describes how I believe the PhysioNet set map to the standard 12-Lead system. The electrode positions and the records obtained from the different leads are definitely important.

For example, if you want to create a 2D EKG loop, use Standard Lead I and . To get a 3D version of that, add . (Plot them against each other, using either plot or plot3, depending on what you want to do. Use axis('equal') for all of the plots, to avoid distortion.)

[FSK]

Many thanks for the detailed explanation. Your input is always helpful and precise.

[Star Strider]

As always, my pleasure!