Before we begin a serious study of 12-lead EKG interpretation, we must first take a moment to give credit to the early pioneers who conducted groundbreaking research that led to the modern 12-lead EKG.
In this article, we’ll talk about Luigi Galvani, Kollicker and Mueller, Ludwig and Waller, and finally Willem Einthoven.
Louis Galvani (1737 – 1798)
This physicist and doctor lived in Bologna, Italy.
In the early 16th century, the relationship between nerves and muscles was not understood. In fact, it wasn’t always obvious that nerves carried electrical impulses to stimulate muscles. It was only in 1790 that Luigi Galvani discovered this connection. In front of an audience of stunned scientists, he made separated frog legs dance by applying an electric current to them.
Rudolf von Kollicker (1817 – 1905)
Johannes Peter Muller (1801 – 1858)
Mueller was a German physiologist who studied at the University of Bonn. He subsequently moved to the Humboldt University of Berlin, where he held the chair of anatomy and physiology. Kollicker was Swiss, but studied in Berlin, as a student of Mueller. More than 50 years after Galvani, in 1855, Kollicker and Mueller demonstrated that the heart beats due to an electrical stimulus. They did this by placing electrodes over the top of a beating heart and then attaching the electrodes to separate frog legs. Every time the heart beat, the frog legs moved.
Augustus D. Waller (1856 – 1922)
Carl Friedrich Willem Ludwig (1816 – 1895)
Carl Ludwig was appointed professor of physiology at the University of Leipzig in 1865. Augustus Waller was his student. At the University of Aberdeen, Waller studied medicine. He became a professor of physiology at St Mary’s Hospital. He not only had a laboratory at home, but his wife, children and pet bulldogs participated in his experiments. In 1887 he used a capillary electrometer to record the first electrocardiogram. He attached photographic film to a slowly moving toy train. He did not think, however, that this information would be useful in hospitals.
Testing done during this time was done by vivisection: open-heart surgery on live animals. It was not until the 1880s that Ludwig and Waller demonstrated that the heart’s electrical signal could be contacted not only by making direct contact with the heart, but by placing electrodes on the skin.
Willem Einthoven (1860 – 1927)
Finally, in 1904, Willem Einthoven was able to graph the electrical signals originating from the heart. He won the Nobel Prize in Medicine in 1924 for his invention which he called the electrocardiogram. Einthoven was a Dutch physician and physiologist. He studied at the University of Utrecht and became a professor at the University of Leiden in 1886. His original machine required 5 people to operate and weighed 500 pounds. He named the deviations he saw using the letters P, Q, R, S, and T. He also showed that this machine could be used to diagnose heart abnormalities.
This first electrocardiogram used only limb leads. It wasn’t until later in the 20th century that chest leads were added to create the 12-lead EKG.
As you continue your study of EKG interpretation, remember these pioneers who made this critical measurement possible.
