Significant ST Elevations for STEMI – is it more than 1 mm or 2 mm; which leads – the precordial or the limb leads?

A lot of people asked me whether I have read anything on the significant ST elevations in ECG for STEM. I remember reading that the American Heart Association in its 2005 Guidelines on Cardiopulmonary Resuscitation and Emergency Cardiac Care mentioned ≥1 mm regardless of whether precordial or limb leads- seems like the Americans have simplified things; whereas when I read the European