You would not believe how many technicians get the placement wrong...and most Doctors don't check behind the technicians.. i was told 2 different times I had heart damage because of bad technician training and poor supervision by Doctors. I have to instruct the technicians on proper lead placements when I have my annual physicals.
There are 10 lead wires 6-Leads V1-V6 Direct Signals are taken. Right Leg act as Electrical Neutral. From 3 points Right Arm , Left Arm and Left Leg, we get 3 signals (Lead I,II,III and derived leads means a mean calculation of these gives another 3 lead signals). Thus, 6+3+3= 12 Lead ECG signal To note we apply 10 Lead wires for Electric Signals.
