History
Historical Timeline
1600
1628
William Harvey
Anatomist William Harvey described the mechanics of blood circulation and the heart's muscle contractions in his book, Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, but did not fully understand the role of specialized conduction tissue.[1]
1892
Albert Frank Stanley Kent
By the 19th century, it was recognized that the heart's contractions were rhythmic, yet the exact mechanism responsible for the synchronization of these contractions remained unclear. Albert Frank Stanley Kent (1863–1958) demonstrated that there are muscular connections between atria and ventricles, not only in the septum, but in the right and left lateral walls of the heart through research on a newborn rat.[2]
1893
Wilhelm His Jr.
Wilhelm His Jr. (1863–1934) described that the atrioventricular bundle is the only communication between atria and ventricles.[3] Before His, the conduction of impulses in the heart was not well understood, and many thought that muscle fibers alone accounted for cardiac contraction. Investigators in the 19th century were starting to explore the possibility that some type of specialized system might be responsible for coordinating the heart's electrical activity, though they lacked the anatomical evidence that His provided.[4]
1900s
General Medical Community
The eponym "bundle of His" was not coined by His himself, but rather by others from the medical community in recognition of his work. The term started to appear in medical literature as researchers and clinicians realized the significance of the atrioventricular bundle in the heart’s conduction system, particularly in the context of diagnosing and understanding conditions like heart block. For instance, there is a 1905 article written by HE Hering, a Prague physiologist, who described the anatomy of the "bundle of His," used by his physician and anatomist peers to aid a patient with the aforementioned condition.[5]
Present
Eponym History
The atrioventricular bundle is eponymously known as the Bundle of His, named after Wilhelm His Jr. (1863–1934), a Swiss internist, cardiologist, and anatomist. His was born in Basel, Switzerland, and earned his medical degree from the University of Leipzig in 1889. He later became a professor at Leipzig and served as dean of the medical faculty in Berlin.[6] His research spanned embryology, histology, and cardiovascular physiology, with particular emphasis on the electrical conduction system of the heart.[6]

Wilhelm His Jr. — Image obtained from Wellcome Collection, licensed under CC BY 4.0
Scientific Contributions
Wilhelm His Jr. made foundational contributions to the understanding of cardiac electrophysiology. In 1893, he identified and described the atrioventricular bundle as a specialized conduction pathway transmitting electrical impulses from the atria to the ventricles.[3] Through anatomical studies in animal models and human specimens, he demonstrated the continuity and course of this structure within the heart. His work provided critical anatomical evidence supporting the concept of a specialized cardiac conduction system.
Beyond his discovery of the atrioventricular bundle, His contributed to the study of heart block and introduced terminology that remains integral to modern cardiology. Over the course of his career, he published extensively on cardiovascular physiology and clinical medicine, influencing both diagnostic practice and anatomical teaching.[7]
Controversies
While His Jr. was not publicly known for actively promoting antisemitism or sympathizing with the Nazis, the same cannot be said for his views on the mentally ill. In his official rector’s address in 1928, titled Über die natürliche Ungleichheit des Menschen (On the Natural Inequality of Humans), His emphasized the negative aspects of contemporary culture, which he believed could be rectified through eugenic measures.[8]
References
Ribatti D. William Harvey and the discovery of the circulation of the blood. J Angiogenes Res. 2009;1:3.
Lev M, Lerner R. The Theory of Kent : A Histologic Study of the Normal Atrioventricular Communications of the Human Heart. Circulation. 1955;12(2).
Bast TH, Gardner WD. Wilhelm His, Jr. and the Bundle of His. Journal of the History of Medicine and Allied Sciences. 1949;4(2):170-187.
Barold SS. Willem Einthoven and the Birth of Clinical Electrocardiography a Hundred Years Ago. Cardiac Electrophysiology Review. 2003;7(1):99-104.
Silverman ME, Hollman A. Discovery of the sinus node by Keith and Flack: on the centennial of their 1907 publication. Heart. 2007;93(10):1184-1187.
Roguin A. Wilhelm His Jr. (1863–1934)—The man behind the bundle. Heart Rhythm. 2006;3(4):480-483.
Anderson RH, Mori S. Wilhelm His Junior and his bundle. Journal of Electrocardiology. 2016;49(5):637-643.
Strous RD, Edelman MC. Eponyms and the Nazi era: time to remember and time for change. The Israel Medical Association journal: IMAJ. 2007;9(3):207-214.
