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A Moment in History

Dr. Thomas Dent Mütter
Dr. Thomas Dent Mütter (1811-1859)

Dr. Thomas Dent Mütter


Thomas Dent Mutter was born on March 9, 1811, in Richmond, VA. His mother died in 1813, and his father died of tuberculosis in 1817. Thomas was orphaned when he was barely 8 years old. His father left him a somewhat meager inheritance and in his early life had to do with less that others with his objectives in life. He was well educated under the tutelage of Robert Carter, his guardian, and in 1824 he started his studies at the Hampden Sidney College of Virginia. He continued with a medical apprenticeship with a Dr. Simms in VA. He was well respected and even at his early age he would do home visits for his medical benefactor with great results. He started medical studies at the University of Pennsylvania, where he earned his MD in 1831. The new young doctor, Thomas Dent Mutter, MD was only 20 years of age.

At the time, Europe was the place to go to if you wanted advanced medical studies. Dr. Mutter had no money, so he applied as a ship surgeon to be able to cross the Atlantic. Once in Europe, he spent time in Paris, where he studied under the tutelage of Dr. Guillaume Dupuytren. He later studied for a short time in England where he met Dr. Robert Liston. Following Dupuytren's teachings, Mutter was fascinated by plastic surgery.

A chance encounter with what was to become his first well-known acquisition of a medical curiosity, Mutter started thinking on how to help those people that were known at that time as “monsters”, patients who the general public did not see, because they did not appear in public. The curiosity in question was a wax reproduction of the face of a French woman who had a “horn” arising from her forehead. This piece is on exhibit at the Mütter Museum.

Back in the United States in 1832, Thomas Dent Mutter changed his last name to give it a more “European” sound and added an “umlaut”, so now he was Thomas D. Mütter, MD. It may also be that he wanted to pay homage to his Scottish-German heritage, who knows? He opened his medical office in Philadelphia and although it took time, eventually he had a thriving practice. One of his specialties was the work on “deformities” so common at the time because of facial scars born out of the use of open fires in houses, and deformities caused by burns and loss of tissue due to chemicals used in local industry. Dr. Mütter is the pioneer of what we call today “Reconstructive Surgery”.

In 1835 he was asked to join the Medical Institute of Philadelphia as an assistant professor of Surgery. He was an instant success. Dr. Mütter was adored by his students because, he would question the students and guide them to discovery instead of just lecturing and leaving. In his Discourse eulogy of Dr. Mütter by Joseph Pancoast he writes:” The power of attracting students near him by his mingled gentleness, energy, and enthusiasm; of fixing their attention by the lucid and methodical arrangements of his Subject, by his clear demonstrations, and sprightly oral elucidations, came so readily to him, and was so early displayed) as to seem almost intuitive.” In 1841 Dr Mütter was appointed Professor of Surgery at the Jefferson Medical College in Philadelphia.

Dr. Mütter had always had poor health, even in childhood, and his dedication to his passion, long hours, took its toll on his body. In 1956 he set sail for Europe and resigned his teaching duties. He was named Emeritus Professor of Surgery. Unfortunately, the trip did not help, and he returned to the US in early 1958. Fearful of another winter in cold Philadelphia, he moved to Charleston, SC, where he died on March 19, 1859.

Dr. Mütter’s story does not end here. He was an avid collector and throughout his short life he had pulled together an impressive collection of medical oddities, samples, and curiosities. Knowing that his life was at an end, he negotiated with the Philadelphia College of Physicians to have them host his collection in perpetuity as well as the creation of a trust fund that would ensure that the public and medical students would have access to this incredible collection. Through the years this collection has increased and is known today as the Mütter Museum of the Philadelphia College of Physicians. I strongly urge our readers to visit this incredible museum. For more information, click here.

Personal notes: In the late 90’s, I attended a meeting of the American Association of Clinical Anatomists.  During the meeting I met Gretchen Worden, who at the time was the Curator of the Mütter museum. Gretchen was inspirational, fun, and a great conversationalist! I had the opportunity to visit Gretchen at the Mütter museum and had the luck to be treated to a “behind the scenes” tour. What an experience! I was saddened to hear that Gretchen Worden passed on August 2, 2004. Still, in my recent visit to the Mütter Museum, I was glad to see a new section at the museum that remembers Gretchen. Her biography can be read here.

I would like to thank Dr. Leslie Wolf for lending me the book by O’Keefe that lead to me writing this article. Dr. Miranda

1. “Dr. Mütter’s Marvels: A True Tale of Intrigue and Innovation at the Dawn of Modern Medicine” O’Keefe, C. 2015 Penguin Random House, LLC
2. “A Discourse Commemorative of the Late Professor T.D. Mütter” Pancoast, J. 1859 J Wilson Publisher
3. “Thomas Dent Mütter: the humble narrative of a surgeon, teacher, and curious collector” Baker, J, et al. The American Surgeon, Atlanta 77:iss5 662-14
4. “Thomas Dent Mutter, MD: early reparative surgeon” Harris, ES; Morgan, RF. Ann Plast Surg 1994 33(3):333-8
5. “5 Things I Learned from Thomas Dent Mütter” O’Keefe C.

"Clinical Anatomy Associates, Inc., and the contributors of "Medical Terminology Daily" wish to thank all individuals who donate their bodies and tissues for the advancement of education and research”.

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Posterior interventricular artery

The right coronary artery usually bifurcates in an area of the posterior aspect of the heart known as the "crux cordis" giving origin to two terminal branches: the posterior interventricular artery (anatomical term) and the posterolateral artery. The posterior interventricular artery is better know to clinicians as the "posterior descending artery" or PDA.

The PDA descends towards the apex cordis where it ends. It gives off several small ventricular branches, but its most important branches are the septal perforators. These branches dive deep and provide blood supply to the posterior 1/3rd of the interventricular septum.

The AV node artery, which provides blood supply to the AV node (a component of the conduction system of the heart) may arise from the PDA instead of arising from the right coronary artery.

The PDA may present with a number of anatomical variations, including:

Posteroinferior view of the heart. IVC=inferior Vena Cava

• arising from the circumflex artery (and absence of the posterolateral artery)
• arising from the first septal perforator of the anterior interventricular artery
• arising from the second diagonal artery
• arising from anterior interventricular artery
• being double, with one PDA arising from the circumflex artery, and another from the right coronary artery, etc.
Image property of: CAA.Inc. Photography: Efrain Klein

Sunao Tawara, M.D.

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.To search all the articles in this series, click here.
Sunao Tawara, M.D. (1873 - 1952) Sunao Tawara was born in the prefecture of Ooita, Kyushu, Japan. Adopted by an uncle (and physician), Tawara studied English and German, and went on to the University of Tokyo medical school, where he graduated an MD in 1901.

In 1903 he traveled to Marburg, Germany, where he started working with Dr. Karl Albert Ludwig Aschoff (1866-1942), a noted pathologist. Tawara’s work led him to the discovery of what today we call the “atrioventricular node” (AV node) and the connections of the AV node and the Bundle of His (the right and left bundle branch). His work with Aschoff led to the eponym of “node of Aschoff-Tawara” for the AV node. Tawara’s work also led to the understanding of the function of the Purkinje fibers. Tawara gave the entire system the name “Reitzleitungssytem” or the “conduction system” of the heart.

In 1906 Dr. Tawara published his discoveries in a German-language article entitled “The Conduction System of the Mammalian Heart — An Anatomicopathological Study on the Atrioventricular Bundle and the Purkinje Fibers”. The same year he returned to Japan and in 1908 became Professor of Pathology at the University of Kyushu until his retirement in 1933.

Dr. Sunao TawaraOriginal imagecourtesy of Wikipedia.
1. "Sunao Tawara" Suma, K. Clin Cardiol (1991) 14; 442-443
2. "Sunao Tawara, A Cardiac Pathophysiologist" Loukas, M. et al Clinical Anatomy 21:2–4 (2008)
3. "Sunao Tawara: A Father of Modern Cardiology" Suma, K. J Pacing Clin Electrophysiol (2001) 24:1; 88- 96

Conduction system of the heart

The conduction system of the heart is formed by a group of specialized cardiac muscle structures that serve as pacemakers and distributors of the electrical stimuli that make the heart beat coordinatedly. It is important to stress the fact that the "conduction system of the heart" is not formed by nerves.

Components of the conduction system of the heart:

• SA node: The sinuatrial (SA) node is a small nodule of cardiac muscle tissue, somewhat horseshoe-shaped that is found at the junction of the superior vena cava and the right atrium. It receives blood supply from the SA node artery, a branch of the right coronary artery. It receives innervation from both sympathetic and parasympathetic nerves

Conduction system of the heart

• AV node: The atrioventricular (AV) node is found at the junction of atria and ventricles in an area known as the "Triangle of Koch". Its function is to delay the electrical impulse passing from the atria to the ventricles by 1/10th of a second, enabling the sequential pumping action of the heart. The eponymic name for the AV node is "node of Aschoff-Tawara", and it receives its blood supply by way of the AV node artery, a branch that usually arises from the right coronary artery

• AV bundle: Also known as the "Bundle of His", this thick bundle of specialized myocardial cells is found in the interventricular septum. It divides into the right and left bundle branches

• Bundle branches: Sometimes known as the "crura" of the Bundle of His, these two divisions of the AV bundle help distribute the electrical stimuli to the ventricular walls. The right bundle branch has an extension that crosses the lumen of the right ventricle, from the base of the anterior papillary muscle to the interventricular septum, forming a cord of tissue known as the "moderator band" or "septomarginal trabecula"

• Purkinje Fibers: These thin fibers are the terminal end of the conduction system of the heart and finish the distribution of the electrical stimuli to all parts of the ventricular walls

Although the structural components of the conduction system of the heart were known, it was Dr. Sunao Tawara (1873-1952) who discovered the AV node and described the connections between the components of what he called the "Reitzleitungssytem" (conduction system) of the heart.

Click on the image for a larger version. Image modified from the original: "3D Human Anatomy: Regional Edition DVD-ROM." Courtesy of Primal Pictures

Circumflex artery

The [circumflex artery]  (CFX) is one of the two branches of the left coronary artery, the other one being the left anterior descending artery (LAD), also known as the anterior interventricular artery.

The prefix [circum-] means "around", while the root term [-flex-] means "to bend". This describes quite well the circumflex artery, which "bends around" the obtuse margin of the heart passing from the anterior surface to the posterior surface of the heart.

The circumflex artery lies deep to the epicardium in the subepicardial fatty layer. It gives off several branches, including small left atrial branches and one or two obtuse marginal arteries (OM1 and OM2)that provide blood supply to the left ventricle in its obtuse margin and posterior ventricular region, as well as a portion of the anterior papillary muscle related to the mitral valve.

Coronary Arteries. The [*] indicates the left coronary artery
There can be interesting anatomical variations in the coronary arteries of the heart. For a detail on these anatomical variations, click here. Heart and coronary artery anatomy is one of the many lecture topics presented by CAA, Inc.

Image property of: CAA.Inc.Artist: Victoria G. Ratcliffe


The prefix [post-] has its origin as a Latin adverb meaning "after". There are two variations in the use of this Latin adverb. The first is in its use as "after" referring to the position of a structure. This use is limited and is the root for the term "posterior". The most common usage is for [post-] to be used in its true meaning of "after" referring to time.

Applications of this prefix include:

postoperative: after the operation
postmortem: from the Latin word [mortis] meaning "death". After death
postpartumfrom the Latin word [partum] meaning "birth". After birth
postprandial: [prandium] is a Latin word meaning "a midday meal". Used to denote "after a meal"
• posthumous: from the Latin word [humus] meaning "ground". Refers to activities performed after burial
• postbellum: after a war

When using pure Latin terms, the word can be used as shown in the listing above, or they can be used as separate entities, such as "post partum", "post mortem", "post bellum", etc. (no hyphens). This leads to interesting facts, such as the pharmacological abbreviation "p.c." which stands for "post cibum"; the meaning of [cibum] is similar to [prandium], so "p.c." means "after a meal"


The prefix [retro-] has a Latin origin and means "posterior", "backwards", or "behind". The main use of this prefix in human anatomy and surgery is "posterior".

Applications of this prefix include:

retroesternal: posterior to the sternum, such as the heart or the internal thoracic vessels
retropharyngeal: posterior to the pharynx, as in the "retropharyngeal space", a potential space found posterior to the pharynx
retroperitoneal: posterior to the peritoneum, referring to abdominal organs found outside and posterior to the peritoneal sac, such as the aorta and kidneys
retrogastric: posterior to the stomach, as in the "retrogastric space", an area also known as the "lesser bursa"
• retroversion: a posterior rotation or turn. Usually refers to the posterior rotation of the uterus or a joint