# Einthoven's triangle

Graphical representation of Einthoven's triangle

Einthoven's triangle is an imaginary formation of three limb leads in a triangle used in electrocardiography, formed by the two shoulders and the pubis.[1] The shape forms an inverted equilateral triangle with the heart at the center that produces zero potential when the voltages are summed. It is named after Willem Einthoven, who theorized its existence.[2]

$I = LA - RA$
$II = LL - RA$
$III = LL - LA$