Book: "La Forma Humana de la línea"

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A Moment in History

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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Details: Written by: Efrain A. Miranda, Ph.D.; Published: December 09, 2024; Hits: 810

Book cover, cropped

I recently added a new book to my library. It is in Spanish and titled "La Forma Humana de la Línea", which can be loosely translated to "The Human Form of the Line", referring to the hand-drawn images of human skeletal anatomy in the book.

"La forma humana de la línea" Katherine Estrada Suazo. ISBN 9789564021898, 2020. América Impresores. Valdivia, Chile

This is an extraordinary book that depicts in 90 pages and 40 plates the human bony anatomy in beautiful detail using a technique described by Leonardo Da Vinci in his “Trattato della Pittura” (A Treatise on Painting), chapter CXXVI. The author, Katherine Estrada Suazo, draws in hyperrealist detail single bones, a full skeleton, fetal skeletons in a seldom seen detail.

The introduction, the words of the artist, the analysis of Leonardo Da Vinci's technique, and the closing comments are a rare form of high level prose with mastery of the Spanish language that reads almost like poetry.

The book itself is a printing marvel. An uncommon large size (9½ by 15¾ inches/24 by 40 cm.), in a high quality acid-free heavy paper, with beautiful typesetting. The book also includes one large insert measuring 29½ by 9 inches (75 by 23 cm).

This work was supported by Morphology Professor, Patricia Hernández Coliñir at the Anatomy Unit of the Medical School of the Universidad Austral de Chile in the city of Valdivia, where it was printed by the América Impresores printing press. The author also received support from the Chilean government through the Regional FONDART (Regional Ministerial Secretary of Culture, Arts and Heritage). As far as I understand, this book is not for sale, which makes it a rare book.

I became aware of this book at the XLIII Annual Chilean Meeting of Anatomy, where I was invited to present the conference I delivered initially in May 2023 at the University of Antwerp, Belgium. An anatomy professor of the Universidad Austral de Chile, Ana Barriga K., had a copy of the book that was gifted to Dr. Carlos Machado, a good friend and famous medical illustrator of Netter’s Anatomy Atlas.

The road to obtaining the copy of the book included contacting the author and with the help of Professor Barriga, and a friend from Chile, the book went from Valdivia (Chile) to Santiago (Chile), to Mexico, and the US. This copy is dedicated by the author as follows: “Dedicated to Dr. Efrain Miranda. Signed in Valdivia, June 2024”, followed by her signature.

In a recent conversation with the author, she stated that "restricting access to this publication was never my intention", and although having the signed book for me is very important, Ms. Estrada has authorized the open download of the digital edition of the book in PDF format, which you can download here. (19 Mb)

Personal remark: As a side note, the city of Valdivia in Chile, where this book was designed and printed, is the city where my mother was born. Dr. Miranda

Lámina1: Cráneo, vista súperolateral

Recientemente agregué un nuevo libro a mi biblioteca. Está en español y se titula "La Forma Humana de la Línea", en referencia a las imágenes dibujadas a mano de la anatomía esquelética humana que aparecen en el libro.

"La forma humana de la línea" Katherine Estrada Suazo. ISBN 9789564021898, 2020. América Impresores. Valdivia, Chile

Este es un libro extraordinario que describe en 90 páginas y 40 láminas la anatomía ósea humana con hermoso detalle utilizando una técnica descrita por Leonardo Da Vinci en su “Trattato della Pittura” (Tratado sobre la pintura), capítulo CXXVI. La autora, Katherine Estrada Suazo, dibuja con detalles hiperrealistas huesos individuales, un esqueleto completo y esqueletos fetales con un detalle pocas veces visto.

La introducción, las palabras del artista, el análisis de la técnica de Leonardo Da Vincy y los comentarios finales son una forma poco común de prosa de alto nivel con dominio del lenguaje español que se lee casi como poesía.

El libro en sí es una maravilla de impresión. Un tamaño grande poco común (9½ por 15¾ pulgadas/24 por 40 cm.), en un papel pesado libre de ácido de alta calidad, con una hermosa composición tipográfica. El libro también incluye un inserto grande que mide 29½ por 9 pulgadas (75 por 23 cm).
Este trabajo fue apoyado por la Profesora de Morfología, Patricia Hernández Coliñir en la Unidad de Anatomía de la Facultad de Medicina de la Universidad Austral de Chile en la ciudad de Valdivia, donde también fue impreso por la imprenta América. El autor también recibió apoyo del gobierno de Chile a través del Fondart Regional (Secretaría Regional Ministerial de Cultura, las Artes y el Patrimonio). Según tengo entendido, este libro no está a la venta, lo que lo convierte en un libro raro.

Me enteré de este libro en la XLIII Reunión Anual Chilena de Anatomía, donde me invitaron a presentar la conferencia que di inicialmente en mayo de 2023 en la Universidad de Amberes, Bélgica. Una profesora de anatomía de la Universidad Austral de Chile, Ana Barriga K., tenía una copia del libro que fue obsequiada al Dr. Carlos Machado, un buen amigo y famoso ilustrador médico del Atlas de Anatomía de Netter.

El camino para obtener la copia del libro incluyó contactar al autor y con la ayuda de la profesora Barriga y un amigo de Chile, el libro viajó desde Valdivia (Chile) a Santiago (Chile), a México y a los Estados Unidos. Este ejemplar está dedicado por la autora de la siguiente manera: “Dedicado al Dr. Efraín Miranda. Firmado en Valdivia, junio de 2024”, seguido de su firma.

En una reciente conversación con la autora, ella afirmó que “nunca fue mi intención restringir el acceso a esta publicación”, y aunque tener el libro firmado para mí es muy importante, la autora ha autorizado la descarga abierta de la edición digital del libro en formato PDF, que pueden descargar aquí. (19 Mb)

Observación personal: Como nota al margen, la ciudad de Valdivia en Chile donde se diseñó e imprimió este libro, es la ciudad donde nació mi madre. Dr. Miranda.

Book: "La Forma Humana de la línea"

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