Limb Lead Reversal In order to understand why the leads look the way they do, we must recall Einthoven’s triangle. The first triangle shows the leads as they are properly placed. Now with the left leg and left arm leads switched, we can see that what is reading as lead I is truly lead II, lead II is truly lead I, and lead III is reversed in polarity. By reversing just two stickers on the patient, many leads are affected. #Diagnosis #Cardiology #ECG #EKG #LimbLeads #LeadIII #Reversal #Einthovens #Triangle