13-Lead ECG
From Gomerpedia
Ah yes, the good ole baker's dozen-lead ECG. Sometimes when 12 leads aren't enough[1] but you don't quite need an echo, then just add lucky lead number 13. Where do you put that one: V7?
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1-Lead ECG 2-Lead ECG 3-Lead ECG 4-Lead ECG 5-Lead ECG 230-Lead ECG
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