Biography

Willem Einthoven received the 1924 Nobel prize in Physiology or Medicine for bringing electrocardiography into clinical medicine through development of the string galvanometer. He was born in May, 1860, in Semarang, Dutch East Indies, on the northern coast of what now is the island of Java in Indonesia. His father was a Dutch military physician and his mother was the daughter of a Dutch government administrator. Young Willem moved to Utrecht with his mother and siblings at the age of 10, several years after his father’s early death. He entered the University of Utrecht as a medical student in 1878. Influenced by the work of Donders and Snellen in the physiology of the eye, he graduated in 1885 with a doctoral thesis on the effect of color differences on stereoscopic vision. At the early age of 25, with strong support of his mentors, Willem Einthoven was appointed to fill the Chair of Physiology at the University of Leiden. He married Frederique Jeanne Louise de Vogel the following year.

As the only participant from the Netherlands at the First International Congress of Physiology, held in Basle in 1889, Einthoven was a witness to the striking demonstration by Augustus D. Waller of the use of the capillary electrometer to record the electrical activity of the human heart. Returning home, Einthoven enthusiastically reported his observations in a review of the meeting published for his Dutch colleagues. We know that Einthoven began similar electrophysiologic studies in humans within a year of the Basel meeting. “I read [your papers] with much pleasure,” Einthoven wrote to Waller from Leiden on July 23, 1890, “and had already the opportunity to deliver a lecture on your extremely interesting investigations and to demonstrate the electromotive changes connected with the beat of the human heart.”

During the period from 1890 to 1895, Einthoven made considerable improvements in the capillary electrometer, but the method had important limitations in frequency response for accurate representation of the ECG. Einthoven’s approach to resolving the problems of the capillary electrometer is a revealing insight into his scientific and mathematical prowess. In an extraordinary series of papers in the mid-1890’s, Einthoven demonstrated that differential equations could be used to “correct” the tracings obtained from the capillary electrometer to approximate the form of a “true” ECG that was not limited by poor frequency response. With transformations tailored to each individual capillary instrument, manually corrected forms of the human electrocardiogram could be derived to represent the range of normal and abnormal findings and to compare findings between tracings taken with different electrometers. This provided Einthoven with a “common standard” for early graphic recording of the electrical activity of the heart.

But significant residual methodologic problems with corrected electrometer recordings constrained Einthoven’s work. What was needed was a galvanometer with high sensitivity that produced an undistorted, directly readable graphic record of the electrical activity of the heart. Einthoven constructed his solution to these technical problems from an eclectic group of advances in industry that evolved at the end of the nineteenth century. During this time, accurate oscillographs were developed for recording rapidly alternating voltages to optimize the efficiency of power stations and transmission lines of the emerging electrical power industry. More accurate and sensitive galvanometers were developed to speed telegraphic transmission of the emerging transoceanic cable industry. Other progress included the engineering of quartz filiaments, the introduction of carbon arc white light source for illumination, the development of apochromatic projecting microscope lenses, and the improvement of photographic emulsion.

The principle of the string galvanometer assembled by Einthoven is that current flow through a conducting wire induces a magnetic field around the wire that is proportional to the current applied. When the wire is suspended in a separate magnetic field, the resulting interaction between the two magnetic fields causes a displacement of the wire that is proportional to the applied current. Production of an extremely thin quartz string with low mass was achieved by drawing out the molten fiber behind an arrow fired from a bow. Projection of the shadow of the moving string, with amplification and photographic recording over time, produces a graphic image of the variation of the source current as projected on the body surface.

Einthoven’s first publication of the human ECG recorded by string galvanometer in 1902 was as much a scientific validation of his mathematical corrections of the capillary electrometer as it was an introduction of new diagnostic instrumentation. As he noted in his Nobel Prize lecture, “there was a certain satisfaction...because this correspondence signified firstly that the earlier calculations were correct, and secondly that the new galvanometer fulfilled its purpose.” According to Waller, in contrast to the electrometer the original string galvanometer had “an accuracy of form that may be regarded as approximately perfect.” By 1908, Einthoven had collected and published high quality tracings of many of the common arrhythmias. A long and productive friendship with Thomas Lewis that began that year further stimulated progress in the understanding of heart rhythms. Einthoven was notified of the Nobel Prize award during the course of a 1924 trip to the United States. Along with visits to New York and Boston, he visited Frank Wilson in Ann Arbor, who took the photograph that illustrates this all too brief sketch. He died in 1927, survived by his wife and four children.

- Paul Kligfield, MD