Suggestions on plotting ECG Graph

Hello, I would like some suggestions on how to plot ECG using plotly with my current setup. I have my ESP32 collecting ECG data and sending them as a string of JSON values every 200ms like this:

As a trial run before this, I have plotted these values as amplitude over no of points and was able to obtain fairly decent ECG graph shape. However, plotting it this way loses the time detail for the x-axis

I would like to have the ECG graph to be similar to below


Any suggestions on how I should approach this?

I would prefer a solution that handles this issue in JS instead of modifying the Arduino sketch.

Thanks in advance!