Coronary sinus


The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers less-oxygenated blood to the right atrium, as do the superior and inferior venae cavae. It is present in all mammals, including humans.

Coronary sinus
Back (posterior) side of the heart, with coronary sinus (blue) labeled
Interior of heart, viewed anteriorly (opening of coronary sinus is labeled)
PrecursorSinus venosus
SourceGreat cardiac vein
Drains toRight atrium
LatinSinus coronarius
Anatomical terminology
[edit on Wikidata]

The name comes from the Latin corona, meaning crown, since this vessel forms a partial circle around the heart. The coronary sinus drains into the right atrium, at the coronary sinus orifice, an opening between the inferior vena cava and the right atrioventricular orifice or tricuspid valve. It returns blood from the heart muscle, and is protected by a semicircular fold of the lining membrane of the auricle, the valve of coronary sinus (or valve of Thebesius). The sinus, before entering the atrium, is considerably dilated - nearly to the size of the end of the little finger. Its wall is partly muscular, and at its junction with the great cardiac vein is somewhat constricted and furnished with a valve, known as the valve of Vieussens consisting of two unequal segments.


The coronary sinus starts at the junction of the great cardiac vein and the oblique vein of the left atrium. The junction of the great cardiac vein and the coronary sinus is marked by the Vieussens valve. It is present in 65% to 87% of the population.[1][2] The coronary sinus runs transversely in the left atrioventricular groove on the posterior aspect of the heart.[3] The coronary sinus then drains into the posterior wall of right atrium. The orifice of the coronary sinus is located to the left of the orifice of inferior vena cava in the right atrium.[4]

The valve of the coronary sinus (also known as "Thebesian valve" is a thin, semilunar (half moon shape) valve located on the anteroinferior part of the opening into the right atrium. It is present in 73% to 86% of autopsied heart.[1]


The coronary sinus receives blood mainly from the small, middle, great and oblique cardiac veins. It also receives blood from the left marginal vein and the left posterior ventricular vein. It drains into the right atrium.

The anterior cardiac veins do not drain into the coronary sinus but drain directly into the right atrium. Some small veins known as Thebesian veins drain directly into any of the four chambers of the heart.

Clinical significanceEdit

Electrodes can be inserted into and through the coronary sinus to study the electrophysiology of the heart. This includes for a coronary sinus electrogram.[3] The coronary sinus connects directly with the right atrium. It will dilate as a result of any condition that causes elevated right atrial pressure, such as pulmonary hypertension.[5] Dilated coronary sinus is also seen in some congenital cardiovascular conditions, such as persistent left supervisor cava,[6] and total anomalous pulmonary venous return.[7]

Additional imagesEdit

See alsoEdit


  1. ^ a b Shah, Sanket S.; Teague, Shawn D.; Lu, Jimmy C.; Dorfman, Adam L.; Kazerooni, Ella A.; Agarwal, Prachi P. (July 2012). "Imaging of the Coronary Sinus: Normal Anatomy and Congenital Abnormalities". RadioGraphics. 32 (4): 991–1008. doi:10.1148/rg.324105220. ISSN 0271-5333.
  2. ^ McAlpine, W. A. (2012). Heart and Coronary Arteries: An Anatomical Atlas for Clinical Diagnosis, Radiological Investigation, and Surgical Treatment. Springer Science & Business Media. ISBN 9783642659836.
  3. ^ a b Issa, Ziad F.; Miller, John M.; Zipes, Douglas P. (2019-01-01), Issa, Ziad F.; Miller, John M.; Zipes, Douglas P. (eds.), "4 - Electrophysiological Testing: Tools and Techniques", Clinical Arrhythmology and Electrophysiology (Third Edition), Philadelphia: Elsevier, pp. 81–124, ISBN 978-0-323-52356-1, retrieved 2021-01-12
  4. ^ a b c d e Ryan, Stephanie (2011). "Chapter 3". Anatomy for diagnostic imaging (Third ed.). Elsevier Ltd. p. 137. ISBN 9780702029714.
  5. ^ Mahmud E, Raisinghani A, Keramati S, Auger W, Blanchard DG, DeMaria AN. Dilation of the coronary sinus on echocardiogram: prevalence and significance in patients with chronic pulmonary hypertension. J Am Soc Echocardiogr. 2001 Jan;14(1):44-9. doi: 10.1067/mje.2001.108538. PMID: 11174433.
  6. ^ Savu C, Petreanu C, Melinte A, Posea R, Balescu I, Iliescu L, Diaconu C, Galie N, Bacalbasa N. Persistent Left Superior Vena Cava - Accidental Finding. In Vivo. 2020 Mar-Apr;34(2):935-941. doi: 10.21873/invivo.11861. PMID: 32111807; PMCID: PMC7157846.
  7. ^ Gupta A, Mishra A, Shrivastava Y. Repair of intracardiac total anomalous pulmonary venous return. Multimed Man Cardiothorac Surg. 2021 Mar 8;2021. doi: 10.1510/mmcts.2021.015. PMID: 33904266.

External linksEdit

  • Anatomy figure: 20:04-03 at Human Anatomy Online, SUNY Downstate Medical Center - "Posterior view of the heart."
  • MedEd at Loyola Radio/curriculum/Vascular/Coronary_sinus.jpg