Pectinate muscles

Pectinate muscles
Section of the heart showing the ventricular septum. (Pectinate muscles labeled at center left.)
Details
Identifiers
Latin	musculi pectinati atrii dextri, musculi pectinati atrii sinistri
FMA	12226
Anatomical terminology [ edit on Wikidata]

The pectinate muscles (musculi pectinati) are parallel muscular ridges in the walls of the atria of the heart.

Structure

In the atria of the heart, there are two different types of walls. Behind the crest (crista terminalis) of the right atrium, also know as the posterior wall, the internal surface is smooth. ^[1] This is called the sinus venarum. The pectinate muscles make up the part of the anterior wall, the wall in front of the sinus venarum, the right atrial appendage. ^[2]

In the left atrium, the pectinate muscles are confined to the inner surface of its atrial appendage. ^[1] They tend to be fewer and smaller than in the right atrium. This is due to the embryological origin of the auricles, which are the true atria. Some sources cite that the pectinate muscles are useful in increasing the power of contraction without increasing heart mass substantially.^{[ citation needed ]}

Pectinate muscles of the atria are different from the trabeculae carneae, which are found on the inner walls of both ventricles.^{[ citation needed ]} The pectinate muscles originate from the crista terminalis.^{[ citation needed ]}

Name

The pectinate muscles are so-called because of their resemblance to the teeth of a comb, as in pecten.^{[ citation needed ]}

References

This article incorporates text in the public domain from page 529 of the 20th edition of Gray's Anatomy (1918)

1. Farré, Jerónimo; Anderson, Robert H.; Cabrera, José A.; Sánchez-Quintana, Damián; Rubio, José M.; Benezet-Mazuecos, Juan (2011-01-01), Stephen Huang, Shoei K.; Wood, Mark A. (eds.), "6 - Cardiac Anatomy for Catheter Mapping and Ablation of Arrhythmias" , Catheter Ablation of Cardiac Arrhythmias (Second Edition), Saint Louis: W.B. Saunders, pp. 74–102, doi:10.1016/b978-1-4377-1368-8.00006-4, ISBN   978-1-4377-1368-8 , retrieved 2020-11-16
2. Drake, Richard L.; Vogl, Wayne; Mitchell, Adam W. M.; Gray, Henry (2024). Gray's anatomy for students (Fifth ed.). Philadelphia, PA: Elsevier. ISBN   978-0-323-93423-7.

External links

• MedEd at Loyola grossanatomy/dissector/labs/thorax/heart/he3_1b.htm
• Anatomy photo:20:13-0104 at the SUNY Downstate Medical Center
• Atlas image: ht_rt_atrium at the University of Michigan Health System - "Right atrium, internal structure, anterior view"