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. 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. 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. 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. Einthoven used these measuring points, by immersing the hands and foot in pails of salt water, as the contacts for his string galvanometer, the first practical ECG machine. Electrodes may be placed distally or proximally on the limb without affecting the recording. The right leg electrode acts to reduce interference, and can be placed anywhere without an effect on the ECG results. Each lead measures the electric field created by the heart during the depolarization and repolarization of myocytes. The electric field can be represented as a vector that changes continuously and can be measured by recording the voltage difference between electrodes.