Circumflex branch of left coronary artery

Artery: Circumflex branch of left coronary artery
Base and diaphragmatic surface of heart. (Circumflex branch not visible, but would be near the coronary sinus.)
Base of ventricles exposed by removal of the atria. (Circumflex branch not visible, but bifurcation of left coronary artery visible at left.)
Latin	ramus circumflexus arteriae coronariae sinistrae
Gray's	subject #142 547
Supplies	posterolateral left ventricle, anterolateral papillary muscle, the sinoatrial nodal artery in 38% of people.
Source	left coronary artery
Branches	left atrial branch left marginal artery posterolateral artery sinuatrial nodal artery (in some people) posterior interventricular artery (in some people)

The "LCX", or left circumflex artery (or circumflex artery, or circumflex branch of the left coronary artery) is an artery of the heart.

Course

It follows the left part of the coronary sulcus, running first to the left and then to the right, reaching nearly as far as the posterior longitudinal sulcus.

Branches

The circumflex artery curves to the left around the heart within the coronary sulcus, giving rise to one or more diagonal or left marginal arteries (also called obtuse marginal branches (OM)) as it curves toward the posterior surface of the heart. It helps form the posterior left ventricular branch or posterolateral artery. The circumflex artery ends at the point where it joins to form to the posterior interventricular artery in ten percent of all cases, which lies in the posterior interventricular sulcus. In the other 90% of all cases the posterior interventricular artery comes out of the right coronary artery.

Structures supplied

The LCX supplies the posterolateral left ventricle and the anterolateral papillary muscle.

It also supplies the sinoatrial nodal artery in 38% of people.

It supplies 15-25% of the left ventricle in right-dominant systems. If the coronary anatomy is left-dominant, the LCX supplies 40-50% of the left ventricle. (See Coronary circulation for description of dominance.)

Additional images

Coronary arteries (labeled in red text) and other major landmarks (in blue text). Left circumflex artery is labeled at right.

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  Cardiac vessels

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  Human heart with coronary arteries

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  Heart coronary territories

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  Heart left lateral coronaries diagram

External links

• SUNY Figs 20:03-03 - "Anterior view of the heart."
• SUNY Figs 20:04-01 - "Posterior view of the heart."
• SUNY Labs 20:09-0104 - "Heart: The Left Coronary Artery and its Branches"
• -442892231 at GPnotebook
• circumflex+branch+of+left+coronary+artery at eMedicine Dictionary
• Image at merck.com
• Overview and diagrams at cardiologysite.com

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.