This 29 year old presented in February 2010 after drinking with friends. He started vomiting, then had onset of chest pain and bilateral arm numbness. Here is his ECG.
The computer read "Probable LVH" and "borderline ST elevation". It did not even suggest acute MI. But as you can see this is an obvious inferior STEMI, with reciprocal ST depression in I and aVL, and even ST depression in V6. Angiography confirmed an RCA occlusion.
If the computer can miss one so obvious, it can (and I know it does) miss many less obvious.
Studies from the 1990's show computer algorithms of 12-lead ECGs are 60-80% sensitive for coronary occlusion. I know of no study that shows they are any better today. 80-lead systems appear to have better overall sensitivity, but with some loss of specificity.