Koch's triangle
Koch's triangle, also known as the triangle of Koch, is named after the German pathologist Walter Koch.[1] It is an anatomical area located at the base of the right atrium, and its boundaries are the coronary sinus orifice, tendon of Todaro, and the septal leaflet of the right atrioventricular valve (also known as the tricuspid valve).[2] It is anatomically significant because the atrioventricular node is located at the apex of the triangle. The base is formed by the coronary sinus orifice and the vestibule of the right atrium, and the hypotenuse is formed by the tendon of Todaro, which is often a continuation off the Eustachian valve. Other structures near to it are the membranous septum and the Eustachian ridge. Variations in the size of Koch's triangle are common.
The triangle of Koch is an important landmark for atrioventricular catheter ablation procedures for the localization of the atrioventricular node.[3]
Tendon of Todaro
The tendon of Todaro delimits the antero-superior boundary of the triangle of Koch. The apex of Koch's triangle is the location of the atrioventricular node.[4] It is part of the fibrous skeleton of the heart, located in the right atrium. It was described by Italian anatomist Francesco Todaro. It is a continuation of the Eustachian valve of the inferior vena cava and the Thebesian valve of the coronary sinus.
The tendon is near-impossible to locate in a living heart, so clinicians use other features to determine the boundaries of the Koch's triangle.[5] Some cardiologists even go as far as rejecting the usefulness of the tendon as an anatomical landmark altogether.[6]
References
- ^ Conti, Andrea A. (2011). "Calling the Heart by Name: Distinguished Eponyms in the History of Cardiac Anatomy" (PDF). The Heart Surgery Forum. 14 (3): E183-7. doi:10.1532/HSF98.20101047. PMID 21676685. S2CID 28989761. Archived from the original (PDF) on 2018-08-02.
- ^ Catheter ablation of cardiac arrhythmias. Huang, Shoei K.,, Miller, John M. (John Michael), 1954- (Third ed.). Philadelphia, PA. 2015. pp. Figure 6-6. ISBN 9780323244299. OCLC 892338420.
{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link) - ^ Feger, Joachim. "Triangle of Koch | Radiology Reference Article | Radiopaedia.org". Radiopaedia. Retrieved 2024-01-19.
- ^ McGuire, Mark A.; Johnson, David C.; Robotin, Monica; Richards, David A.; Uther, John B.; Ross, David L. (1992-09-15). "Dimensions of the triangle of Koch in humans". The American Journal of Cardiology. 70 (7): 829–830. doi:10.1016/0002-9149(92)90574-I. ISSN 0002-9149. PMID 1519544.
- ^ Yen Ho & Anderson 2000.
- ^ James 1999.
Further reading
- Sumitomo, Naokata; Tateno, Shigeru; Nakamura, Yoshihide; Ushinohama, Hiroya; Taniguchi, Kazuo; Ichikawa, Rie; Fukuhara, Junji; Abe, Osamu; Miyashita, Michio; Kanamaru, Hiroshi; Ayusawa, Mamoru; Harada, Kensuke; Mugishima, Hideo (2007). "Clinical Importance of Koch's Triangle Size in Children". Circulation Journal. 71 (12): 1918–21. doi:10.1253/circj.71.1918. PMID 18037746.
- Francalanci, Paola; Drago, Fabrizio; Agostino, Domenico Antonio; Liso, Gaetano; Giommo, Vincenzo; Boldrini, Renata; Ragonese, Pietro; Bosman, Cesare (1998). "Koch's Triangle in Pediatric Age: Correlation with Extra- and Intracardiac Parameters". Pacing and Clinical Electrophysiology. 21 (8): 1576–9. doi:10.1111/j.1540-8159.1998.tb00245.x. PMID 9725156.
- Inoue, Shin; Becker, Anton E. (1998). "Koch's Triangle Sized Up: Anatomical Landmarks in Perspective of Catheter Ablation Procedures". Pacing and Clinical Electrophysiology. 21 (8): 1553–8. doi:10.1111/j.1540-8159.1998.tb00242.x. PMID 9725153.
- Sánchez-Quintana, Damián; Picazo-Angelín, Beatriz; Cabrera, Alberto; Murillo, Margarita; Cabrera, José Ángel (2010). "Koch's Triangle and the Atrioventricular Node in Ebstein's Anomaly: Implications for Catheter Ablation". Revista Española de Cardiología. 63 (6): 660–7. doi:10.1016/S1885-5857(10)70140-7. PMID 20515623.
- Anderson, R. H.; Cook, A. C. (2007). "The structure and components of the atrial chambers". Europace. 9 (Suppl 6): vi3–9. doi:10.1093/europace/eum200. PMID 17959691.
- James, Thomas N. (1999). "The Tendons of Todaro and the "Triangle of Koch":: Lessons from Eponymous Hagiolatry". Journal of Cardiovascular Electrophysiology. 10 (11): 1478–1496. doi:10.1111/j.1540-8167.1999.tb00207.x. ISSN 1045-3873. PMID 10571368. Retrieved 2025-05-13.
Todaro tendons are too often absent (or multiple) to warrant use as anatomic landmarks
- Yen Ho, Siew; Anderson, Robert H. (2000). "How Constant Anatomically is the Tendon of Todaro as a Marker for the Triangle of Koch?". Journal of Cardiovascular Electrophysiology. 11 (1): 83–89. doi:10.1111/j.1540-8167.2000.tb00741.x. ISSN 1045-3873. PMID 10695467. Retrieved 2025-05-13.
the tendon of Todaro is not visible in the operating room or in the catheterization laboratory. Instead, clinicians use as surrogate a projected line between the eustachian valve and the central fibrous body
External links
- "Triangle of Koch". University of Minnesota.
- Voka Anatomy Atlas – 3D visualization of the internal heart structures and Koch's triangle
- "Illustration". health-pictures.com.