It’s an Irish site. It has excellent video demonstrations of the underlying pathophysiology of ECG findings correlated with simultaneous video of ECG evolution.
Increasing ST elevation. STEMI vs. dynamic early repolarization vs. pericarditis.
Here is a series of ECGs with increasing ST elevation (STE). They are of a young male with pleuritic, but not positional, chest…
Great site, I started there when I wanted to understand the basics! Try it!