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Jean George Bachmann
(1877 – 1959)
French physician–physiologist whose experimental work in the early twentieth century provided the first clear functional description of a preferential interatrial conduction pathway. This structure, eponymically named “Bachmann’s bundle”, plays a central role in normal atrial activation and in the pathophysiology of interatrial block and atrial arrhythmias.
As a young man, Bachmann served as a merchant sailor, crossing the Atlantic multiple times. He emigrated to the United States in 1902 and earned his medical degree at the top of his class from Jefferson Medical College in Philadelphia in 1907. He stayed at this Medical College as a demonstrator and physiologist. In 1910, he joined Emory University in Atlanta. Between 1917 -1918 he served as a medical officer in the US Army. He retired from Emory in 1947 and continued his private medical practice until his death in 1959.
On the personal side, Bachmann was a man of many talents: a polyglot, he was fluent in German, French, Spanish and English. He was a chef in his own right and occasionally worked as a chef in international hotels. In fact, he paid his tuition at Jefferson Medical College, working both as a chef and as a language tutor.
The intrinsic cardiac conduction system was a major focus of cardiovascular research in the late nineteenth and early twentieth centuries. The atrioventricular (AV) node was discovered and described by Sunao Tawara and Karl Albert Aschoff in 1906, and the sinoatrial node by Arthur Keith and Martin Flack in 1907.
While the connections that distribute the electrical impulse from the AV node to the ventricles were known through the works of Wilhelm His Jr, in 1893 and Jan Evangelista Purkinje in 1839, the mechanism by which electrical impulses spread between the atria remained uncertain.
In 1916 Bachmann published a paper titled “The Inter-Auricular Time Interval” in the American Journal of Physiology. Bachmann measured activation times between the right and left atria and demonstrated that interruption of a distinct anterior interatrial muscular band resulted in delayed left atrial activation. He concluded that this band constituted the principal route for rapid interatrial conduction.
Subsequent anatomical and electrophysiological studies confirmed the importance of the structure described by Bachmann, which came to bear his name. Bachmann’s bundle is now recognized as a key determinant of atrial activation patterns, and its dysfunction is associated with interatrial block, atrial fibrillation, and abnormal P-wave morphology. His work remains foundational in both basic cardiac anatomy and clinical electrophysiology.
Sources and references
1. Bachmann G. “The inter-auricular time interval”. Am J Physiol. 1916;41:309–320.
2. Hurst JW. “Profiles in Cardiology: Jean George Bachmann (1877–1959)”. Clin Cardiol. 1987;10:185–187.
3. Lemery R, Guiraudon G, Veinot JP. “Anatomic description of Bachmann’s bundle and its relation to the atrial septum”. Am J Cardiol. 2003;91:148–152.
4. "Remembering the canonical discoverers of the core components of the mammalian cardiac conduction system: Keith and Flack, Aschoff and Tawara, His, and Purkinje" Icilio Cavero and Henry Holzgrefe Advances in Physiology Education 2022 46:4, 549-579.
5. Knol WG, de Vos CB, Crijns HJGM, et al. “The Bachmann bundle and interatrial conduction” Heart Rhythm. 2019;16:127–133.
6. “Iatrogenic biatrial flutter. The role of the Bachmann’s bundle” Constán E.; García F., Linde, A.. Complejo Hospitalario de Jaén, Jaén. Spain
7. Keith A, Flack M. The form and nature of the muscular connections between the primary divisions of the vertebrate heart. J Anat Physiol 41: 172–189, 1907.
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This article is part of the series "A Moment in History" where we honor those who have contributed to the growth of medical knowledge in the areas of anatomy, medicine, surgery, and medical research.
Friedrich Gustav Jakob Henle
Friedrich Gustav Jakob Henle (1809 -1885) German physician, anatomist, histologist, and physiologist. Born in the city F?rth, Henle entered the University of Bonn and studied anatomy with Johannes Muller (1801 – 1859), a professor of anatomy and histology. Henle dedicated his efforts to scientific research, and became the managing editor of the journal “Archives of Anatomy, Physiology, and Scientific Medicine” founded by Muller.
Henle’s career in Berlin suffered after he was arrested for 40 days in jail, because of his past membership in a radical liberal and nationalistic student fraternity, the Burschenschaften. He transferred from Berlin to Zürich where he founded the School of Rational Medicine.
Among his publications, the “Allgemeine Anatomie “(1841) is considered the first treatise on microscopic histology. Also, his book “Handbuch der systematischen Anatomie des Menschen” (Handbook of Human Systematic Anatomy) is a great anatomy book with good illustrations.
Henle moved from Zürich to Heidelberg, and from there to Gôttingen, where he accepted the position of Professor of Anatomy. He stayed at Gôttingen until his death in 1885.
Henle’s many remembered contributions are mostly in the area of histology. His name is found in many eponyms. The eponym most associated with his name is “Henle’s loop”, part of the tubular component of a nephron.
- Crypts of Henle: Microscopic pockets located in the conjunctiva of the eye
- Henle's fissure: Fibrous tissue between the cardiac muscle fibers.
- Henle's ampulla: Ampulla of the uterine (Fallopian) tube
- Henle's layer: Outer layer of cells of root sheath of a hair follicle.
- Henle's ligament (tendon): Tendon of the transversus abdominis muscle.
- Henle's membrane: The layer forming the inner boundary of the choroid of the eye
Sources:
1. "The Origin of Medical Terms" Skinner, HA 1970 Hafner Publishing Co.
2. “The Man Behind the Eponym Jacob Henle: Henle’s Layer of the Internal Root Sheath” Steffen C. Am J Dermatopath (2001) 23(6): 549–551
3. “The life of Jacob Henle” Robinson A Medical Life Co. 1921.
Original image in the public domain. Courtesy of Wikipedia.
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These two terms are opposite, yet they need to be reviewed together. The word [antegrade] is Latin and means "to go before" or in a variation of the term, [anterograde] meaning "to go anterior or moving forward". The word [retrograde] is also Latin and means "to go or move behind (or posterior)". Based on their etymology, these words are of no use and confusing.
Now, if we use these words in the context of "proximal and distal" then the story changes. Based on our working definition of proximal and distal, the definition would be as follows:
Antegrade: Moving or in a relationship of proximal to distal. In the case of a hollow organ containing a moving fluid, it would mean "going with the flow"
Retrograde: Moving or in a relationship of distal to proximal. In the case of a hollow organ containing a moving fluid, it would mean "going against the flow"
The confusion caused by the lack of proper definition can be illustrated by this Letter to the Editor, published in The American Journal of Sports Medicine.
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The prefix [-iso-] originates from the Greek [ίσος] meaning "equal". In medical terminology it is used to mean "same". Applications of this prefix include:
- Isometric: Same length. An isometric muscular contraction occurs when the muscle contracts, but the length of the muscle is the same, it does not change
- Isotonic: Equal or same tension. Refers to solutions that have the same osmotic pressure
- Isomorphous: Same shape or form
- Isosceles: Equal legs. An isosceles triangle is formed by three "legs" that have the same length
Note: The links to Google Translate in these articles include an icon that will allow you to hear the Greek or Latin pronunciation of the word.
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The word [cingulum] is Latin and means "belt" or "girdle". The term was also used by Roman soldiers to denote a sword belt. The short sword of the Romans was called a "gladius" and this was the earlier name for the sternum. The plural Latin form for cingulum is "cingula".
The adjectival form for this word is [cingulate] and means "belted", "girdled", or "shaped like a belt"
In human anatomy the term [cingulum] or cingulate gyrus is used to describe a brain gyrus found deep in the medial aspect of the brain hemisphere, hugging the corpus callosum like a girdle. The cingulate gyrus (in green in the accompanying image) is part of the limbic system.
Interesting side notes: The Latin word cingulum evolved into the Spanish "cincha" used to refer to a strong leather belt, while in English it evolved into "cinch"... so when you are in "a cinch" you are basically "tied up" or "in a girdle". Also, the Greek equivalent term for cingulum is zoster, which explains why the pathology is called "herpes zoster", as the presentation of the pathology is in a tight, belt-like abdominothoracic rash.
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This article is part of the series "A Moment in History" where we honor those who have contributed to the growth of medical knowledge in the areas of anatomy, medicine, surgery, and medical research.
Bernhard Siegfried Albinus
Bernhard Siegfried Albinus (1697-1770). German-Dutch physician, surgeon, and anatomist, Albinus was born in Frankfurt an der Oder, but lived most of his life in Leyden, in Holland, his adopted country. His real name was Bernhard Siegfried Weiss, which means “white” in German, the Latin version of which is “albus”, from where derives his Latinized name “Albinus”.
His father was also a physician, Bernard (or Bernhard) Weiss (1653 – 1721). He also took the last name Albinus, which makes following their history and genealogy a bit difficult.
Albinus moved to Leyden (Leiden) when he was only five years old, excelling at his studies and entering the University of Leyden at 12. He later moved to Paris, France to continue his studies on anatomy and surgery. He received his medical degree in 1719.
He began work at the University of Leyden as a Professor of Anatomy and Surgery, where he continued working until his death in 1770. He is considered one the most well-known anatomists of the 18th century.
Because of his work with his colleague Herman Boerhaave (1668-1738), Albinus came in contact with Jan Wandelaar (1690-1759) an artist and engraver. It was this collaboration and the art of Jan Wandelaar which have made Albinus’ books and illustration famous. Albinus was criticized for the luscious, detailed, and sometimes strange backgrounds of his anatomical images, yet he defended Jan Wandelaar and his artistic expression. Albinus and Jan Wandelaar were dedicated to the faithful reproduction of anatomy in their publications, developing a grid system to reduce errors in production and printing.
During his tenure, Albinus was twice appointed Rector of the University and President of the College of Surgeons of Leyden. During this time, he became aware of the discovery of the copper plates created by Eustachius’ and lost for over a hundred years. In 1744 he published the plates in the book “Explanation of the Anatomical Tables of Eustachius “with his comments, stressing the fact that these images were better than those of Vesalius, published in 1543. This is no surprise, as Vesalius’ images were woodcuts, done before the technique of printing with copper plates became popular.
Although not well-known, Albinus’ name is eponymically attached to the risorius and scalenus minimus muscles. His famous publications include “Historia musculorum hominis” in 1734), “Icones ossium foetus humani” in 1737, “Tabulæ sceleti et musculorum corporis humani” in 1749, etc.
Some of Albinus and Jan Wandelaar images can be seen here. Click on the image to see a larger depiction:
Sources:
1. "Bernard Siegfried Albinus (1697-1770), German-Dutch anatomist" JAMA (1966), 196 (10): 910
2.“Bartholomeo Eustachio – The Third Man: Eustachius Published By Albinus” Fahrer, M. Ann Anat 187 (2005) 555—573
3. “Attic perfection in anatomy: Bernhard Siegfried Albinus (1697–1770) and Samuel Thomas Soemmerring (1755–1830)” Hildebrand, R. Ann Anat 187 (2005) 555—573
4. “Two Conceptions of the Human Form: Bernard Siegfried Albinus and Andreas Vesalius” Elkins, J. Artibus et Historiae, 7:14 (1986) 91-106
5. “Bartolomeo Eustachio: His Influence on Albinus and the Anatomical Models at La Specola, Florence” Hilloowala, R. J Hist Med All Sci (1986); 41 (4): 442 -462
Portrait and all other images in this article are in the public domain. Courtesy of Wikipedia. The links to read the books online courtesy of Archive.org.
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The word [canthus] arises from the Greek [kanthos] meaning "angle". It was later adopted into New Latin as [canthus]. The Latin plural form is [canthi].
In human anatomy it is used to describe the angles in the eye formed by the joining of the superior and inferior eyelids.
Each eye has a lateral and a medial canthus. At the medial canthus there is a small elevation of mucosa called the caruncle.
As an interesting note, the lateral canthal lines are a fancy way to refer to "crow's feet", the wrinkles that diverge from the lateral canthus.
Image modified from the original. Public domain. Courtesy of Wikipedia.