The 80-lead ECG is more sensitive than a 12 lead ECG for detecting infarcts in the posterior, right, inferior, and high lateral areas of the heart.
80-lead ECG body surface mapping was applied to 1830 patients in the emergency department with moderate to high risk chest pain. 12 lead ECG detected STEMI in 91 patients and an additional 25 patients had 80-lead-only STEMI.

The authors and an editorialist point out some interesting issues and unanswered questions regarding the application of this technology:

• Since almost all of the 80-lead-only STEMI patients had an elevated troponin, is this just another way of diagnosing NSTEMI?
• Since there are no convincing data demonstrating a benefit from immediate therapy of NSTEMI, would the earlier detection improve outcome?
• Angiographic findings in the 80-lead-only STEMI group showed similar lesions to 12-lead STEMI patients, with more frequent involvement of posterior (left circumflex) and right ventricular (right coronary artery) regions
• Is the increase in sensitivity offered by the 80-lead ECG accompanied by a decrease in specificity?

More research is needed – preferably in a randomised controlled trial – before this interesting technology is rolled out in emergency departments
Acute detection of ST-elevation myocardial infarction missed on standard 12-Lead ECG with a novel 80-lead real-time digital body surface map: primary results from the multicenter OCCULT MI trial.
Ann Emerg Med. 2009 Dec;54(6):779-788
The 80-lead ECG: more expensive NSTEMI or Occult STEMI
Ann Emerg Med. 2009 Dec;54(6):789-90