The circumflex branch of left coronary artery, or left circumflex artery or circumflex artery, is a branch of the

left coronary artery The left coronary artery (LCA) is a coronary artery that arises from the aorta above the left cusp of the aortic valve, and feeds blood to the left side of the heart muscle. It is also known as the left main coronary artery (LMCA) and the left ma ...

Description

The left circumflex artery follows the left part of the

coronary sulcus The coronary sulcus (also called coronary groove, auriculoventricular groove, atrioventricular groove, AV groove) is a groove on the surface of the heart at the base of right auricle that separates the atria from the ventricles. The structure co ...

, running first to the left and then to the right, reaching nearly as far as the

posterior longitudinal sulcus The posterior interventricular sulcus or posterior longitudinal sulcus is one of the two grooves that separates the ventricles of the heart The heart is a muscular Organ (biology), organ in most animals. This organ pumps blood through th ...

. There have been multiple anomalies described, for example the left circumflex having an aberrant course from the

right coronary artery In the blood supply of the heart, the right coronary artery (RCA) is an artery originating above the right cusp of the aortic valve, at the right aortic sinus in the heart. It travels down the right coronary sulcus, towards the crux of the hea ...

Branches

The circumflex artery curves to the left around the

heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...

within the

, giving rise to one or more

left marginal arteries The left marginal artery (or obtuse marginal artery) is a branch of the circumflex artery, originating at the left atrioventricular sulcus, traveling along the left margin of heart towards the apex of the heart. See also * Right marginal branch ...

(also called obtuse marginal branches) 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 the coronary circulation, the posterior interventricular artery (PIV, PIA, or PIVA), most often called the posterior descending artery (PDA), is an artery running in the posterior interventricular sulcus to the apex of the heart where it meets ...

in 15% of all cases, which lies in the

posterior interventricular sulcus The posterior interventricular sulcus or posterior longitudinal sulcus is one of the two grooves that separates the ventricles of the heart The heart is a muscular Organ (biology), organ in most animals. This organ pumps blood through th ...

. In the other 85% of all cases the posterior interventricular artery comes out of the right coronary artery. When the left circumflex supplies the

posterior descending artery In the coronary circulation, the posterior interventricular artery (PIV, PIA, or PIVA), most often called the posterior descending artery (PDA), is an artery running in the posterior interventricular sulcus to the apex of the heart where it mee ...

in those 15% of cases, it is known as a left dominant circulation.

Structures supplied

The circumflex artery supplies the posterolateral

left ventricle A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the upper ...

and the anterolateral

papillary muscle The papillary muscles are muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (also known as the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prol ...

. It also supplies the

sinoatrial nodal artery The sinoatrial nodal artery (or sinuatrial nodal artery or sinoatrial artery) is an artery of the heart which supplies the sinoatrial node, the natural pacemaker center of the heart, and arises from the right coronary artery in around 60% of peopl ...

in 38% of people. It supplies 15-25% of the

in right-dominant systems. If the coronary anatomy is left-dominant, the circumflex artery supplies 40-50% of the left ventricle.

Additional images

File:Cardiac vessels.png, Cardiac vessels File:Human heart with coronary arteries new.png, Human heart with coronary arteries File:Heart coronary territories.jpg, Heart coronary territories File:Heart left lateral coronaries diagram.svg, Heart left lateral coronaries diagram

References

External links

* - "Anterior view of the heart." * - "Posterior view of the heart." * - "Heart: The Left Coronary Artery and its Branches"
Image at merck.com

{{Authority control Arteries of the thorax