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 Resuscitation Council (ERC) guidelines on resuscitation (2005) – I remembered that the Europeans are still insisting on ≥2 mm in precordial leads and ≥1 mm is enough in the limb leads. Then when I read the new Malaysian guidelines on STEMI, I found out that the Malaysian guidelines that use this criteria ≥1 mm: I,II,III, aVL, aVF, V4 – 6 and ≥2mm in V1-V3. So which is which now? Then I come across this table below adapted from the ECG book by Chan et al that I find really helpful:

Study	Minimum Consecutive Leads	Minimum ST Elevation (mm) Limb leads	Minimum ST Elevation (mm) Precordial leads
AHA/ACC	2	≥1	≥1
GISSI-1	1	≥1	≥2
GISSI-2	1	≥1	≥2
GUSTO	2	≥1	≥2
TIMI	2	≥1	≥1
Minnesota Code	1	≥1 mm: in leads I,II,III, aVL, aVF, V5-6 ≥2mm: V1-V4

Reference:

Chan TC, Brady WJ, Harrigan RA et al. ECG in Emergency Medicine and Acute Care. 1st ed. Pennsylvania: Elsevier Mosby; 2005.

Looks like the Malaysian guidelines is most similar to the Minnesota Code (which is often used too in other studies and guidelines)…..

See the editorial article by MacFarlane in Heart Journal year 2000. You can download the article free by clicking here.

The Malaysia CPG on STEMI can be downloaded from the MOH website.