ocr: The Einthoven lead system was +aUR - - - - I - +aVL more These extended leads have by in angles the addition of frontal of -150, three plane. - - - These are aUR, avl, and aUF. -300 and +1 - +90 degrees. Note -90° ell!! t180°. 00 EKG axis angles +IIT +IT are measured this +90° +aVF way!!