Milestones:String galvanometer to record the human electrocardiogram

Title

String Galvanometer to Record a Human Electrocardiogram, 1901-1905

Citation

On 22 March 1905, the first successful clinical recording of a human electrocardiogram (ECG) took place at this location, which at the time was the Academic Hospital Leiden. Willem Einthoven’s pioneering work, from 1901 to 1905, resulted in a string galvanometer specifically designed to measure and record the heart’s electrical activity, which made this medical achievement possible. This invention marked the beginning of electrocardiography as a major clinical diagnostic tool.

Street address(es) and GPS coordinates of the Milestone Plaque Sites

Leiden University Medical Center,Albinusdreef 2, 2333 ZA Leiden, The Netherlands.Coordinates: 52.166128, 4.477316, Leiden University Medical Center,Albinusdreef 2, 2333 ZA Leiden, The Netherlands.Coordinates: 52.166128, 4.477316

Details of the physical location of the plaque

We intend the plaque to be mounted at eye level on a pillar in the entrance hall of the Leiden University Medical Center, where the first cardiogram from a patient was recorded via a telephone link and using the string galvanometer. The pillar (see Fig.1) is a few meters from the door of the main entrance.

Fig.1 The position of the plaque in the entrance hall of the Leiden University Medical Center. In the background is the reception desk.

How the intended plaque site is protected/secured

The LUMC is publicly accessible, but there is permanent surveillance by guards and video camera.

Historical significance of the work

Worldwide, 12-lead 10-second electrocardiograms are routinely made when a patient sees a cardiologist, and on many other occasions, including emergency situations like acute coronary syndrome (acute myocardial infarction), where the electrocardiogram contributes to important triaging decisions. Additionally, electrocardiography has new applications, e.g., in intensive care monitoring and in long-term ambulatory monitoring, the latter, e.g., for the purpose of the detection of cardiac rhythm disturbances. Thus, electrocardiography, and various forms of electrocardiographs, have become an important and indispensable part of medical practice. The three “Einthoven leads” (the electrocardiographic derivations as originally used by Willem Einthoven, using electrodes at the right and left arms and at the left foot) still constitute part of the current standard 12-lead electrocardiogram. By recording and interpreting electrocardiograms in a variety of patients and volunteers, and by commercially producing various copies of his string galvanometer, Einthoven was literary instrumental in the quick rise of interest of clinicians in electrocardiography.

Features that set this work apart from similar achievements

When Einthoven started his experiments, several others were involved in developing sensitive galvanometers to record the electrical signal of the heart. However, none of these approached the sensitivity and reliability of Einthoven's string galvanometer.

Einthoven started to analyze the data resulting from the experiments performed with the Lipmann capillary electrometer, the Arsonval galvanometer and the Thomson galvanometer. This analysis led him to investigate the physical/mathematical characteristics of the instruments. Lipmann’s electrometer in particular held his attention. Not being a physicist, Einthoven had to overcome the problems of the mathematical equations. With the help of Nobel prize winner H. A. Lorentz (1853–1928), the famous Leiden professor of physics, he was able to solve the mathematical calculations that modeled the physical behavior of the mercury column. This mathematical approach provided him with a sound basis for fundamentally improving the string galvanometer. This instrument would combine the best of both worlds: the swiftness of the galvanometers and the sensitivity of the capillary electrometer.

Einthoven conducted clinical trials when he connected his laboratory with the academic hospital Leiden. The string galvanometer he had constructed was too heavy to be transported to the hospital. However, patients at the academic hospital were connected to the string galvanometer in Einthoven’s laboratory at about 1.5 km distance by means of a telephone line. Readable electrocardiograms were successfully taken. Based on these clinical recordings Einthoven characterized the shape of electrocardiograms as a number of successive “waves”, the in the time zones P, Q, R, S, and T and U waves, a convention which is still in use.

The first time a patient's electrocardiogram was successfully recorded in this way was on Mach 22, 1905. This becomes evident from Einthoven's paper Reference [7] on page 127.

Fig. 4 Patient sitting in the university hospital while his telecardiogram is being taken in the physiological laboratory. The hands are immersed in a strong salt solution (NaCl) for good contact between the body and the telephone line.

In 1924, Einthoven was awarded the Nobel Prize in Physiology or Medicine "for his discovery of the mechanism of the electrocardiogram".

Significant references

<u>Nota bene</u>: In the days of Einthoven, the lingua franca of science was dynamically changing. This caused Einthoven to write his scientific papers in German, in French and later also in English. The non-English titles of the following reference list have all been translated into English [English titles between square brackets]. Papers in the English language have been marked by an *.

[1] Einthoven W., "Über die Form des menschlichen Elektrocardiogramms", [About the shape of the human electrocardiogram]. Pflüg Arch ges Physiol 60: 101-123, 1895.

[2] Einthoven W., "Beitrag zur theorie des Capillar-Elektrometers", [A contribution to the theory of the capillary electrometer]. Pflüg Arch ges Physiol 79: 1-25, 1900.

[3] Einthoven W., "Über das normale menschliche Elektrocardiogramm und über die capillär-elektrometrische Untersuchung einiger Herzkranken", [About the normal human electrocardiogram and about investigating some cardiac patients with the capillary electrometer (with K. de Lint)]. Pflüg Arch ges Physiol 80: 139-160, 1900.

[4] Einthoven W., "Un nouveau galvanomètre", [A novel galvanometer]. Arch néerl des Sciences Exact Nat serie 2 vol 6: 625-633, 1901.

[5] Rosenstein S.S., "Galvanometrische registratie van het menschelijk electrocardiogram", [Galvanometric registration of the human electrocardiogram]. In: Remembrance Volume, pp. 101-106, Eduard IJdo, Leiden, The Netherlands, 1902.

[6] Einthoven W., "Die galvanometrische Registerung des menschlichen Elektrokardiogram: Zugleich eine Beurteilung der Anwendung des Capillär-Elektrometers in der Physiologie", [Galvanometric recording of the human electrocardiogram: at the same time an evaluation of the use of the capillary electrometer in physiology]. Pflüg Arch ges Physiol 99: 472–480, 1903.

[7] Einthoven W., "Le télécardiogramme", [The telecardiogram]. Arch Int Physiol 4: 132-164, 1906

[8*] Mathewson F.A.L. and Jackh H., "The telecardiogram", [Translation of selected paragraphs from Einthoven W., "Le télécardiogramme". Arch Int Physiol 4: 132-164, 1906]. Am Heart J 49: 77-82, 1955.

[9*] Blackburn H.W., "The telecardiogram", [Translation, starting at paragraph 35, from Einthoven W., "Le télécardiogramme". Arch Int Physiol 4: 132-164, 1906]. Am Heart J 53: 602-615, 1957.

[10] Einthoven W., "Weiteres über das Elektrokardiogramm"; nach gemeinschaftlich mit Dr. B. Vaandrager angestellten Versuchen mitgeteilt [More about the electrocardiogram; communicated after research in cooperation with Dr. B. Vaandrager]. Pflüg Arch ges Physiol 122: 517-584, 1908.

[11] Einthoven W., "Die Konstruktion des Saitengalvanometers", [Construction of the string galvanometer]. Pflüg Arch ges Physiol 130: 287-321, 1909.

[12] Einthoven W., "Über die Deutung des Elektrokardiogramms", [About the interpretation of the electrocardiogram]. Pflüg Arch ges Physiol 149: 65-86, 1912.

[13] Einthoven W., Fahr G. and De Waart A., "Über die Richtung und die manifeste Grosse der Potentialschwankungen im menschlichen Herzen und uber den Einfluss der Herzlage auf die Form des Elektrokardiogramms", [On the direction and manifest size of the variations of the potentials in the human heart and on the influence of the position of the heart on the form of the electrocardiogram]. Pflugers Arch ges Physiol 150: 275-315, 1913.

[14*] Hoff H.E. and Sekelj P., "On the direction and manifest size of the variations of potential in the human heart and on the influence of the position of the heart on the form of the electrocardiogram", [Translation of Einthoven W., Fahr G. and De Waart A., "Über die Richtung und die manifeste Grosse der Potentialschwankungen im menschlichen Herzen und uber den Einfluss der Herzlage auf die Form des Elektrokardiogramms", Pflugers Arch ges Physiol 150: 275-315, 1913]. Am Heart J 40: 163-211, 1950

[15*] Einthoven W., "The string galvanometer and the measurement of the action currents of the heart", (Nobel Lecture, December 11, 1925). In: Nobel Lectures, Physiology or Medicine 1922-1941, Elsevier Publishing Company, Amsterdam, 1965

[16*] Lewis T. "Willem Einthoven, MD, PhD", (Obituary). Br Med J 2(3483): 664-665, 1927

[17*] Snellen H.A., "Willem Einthoven, Father of electrocardiography". Kluwer Academic Publishers, Dordrecht, The Netherlands, 1995.

[18*] Dijk J, and Van Loon, B., "The electrocardiogram centennial: Willem Einthoven (1860-1927)". Proc IEEE 94: 2182-2185, 2006

[19*] Grob, B., "Willem Einthoven and the Development of the String Galvanometer. How an Instrument Escaped the Laboratory". History and Technology, Vol. 22, no. 4, 2006, pp. 369-390.

[20*] Burnett, J., "The origin of the electrocardiograph as a clinical instrument". Medical History, Supplement no. 5, 1985, pp. 53-76.

[21*] Burchell, H.B., "Did Einthoven invent a string galvanometer?". Br. Heart J., Vol. 57, 1985, pp. 190-193.