Corpus: Coronary artery: Unterschied zwischen den Versionen

The coronary arteries are the two blood vessels that encircle the heart like a ring and supply blood to the heart muscle, including their branching vessels.

The heart’s blood supply comes from two main coronary arteries: the left coronary artery (LCA) and the right coronary artery (RCA), along with their many branches.

These coronary arteries arise from the ascending part of the aorta, specifically from the right and left aortic sinuses.

Overview of Coronary Artery Branches:

• Left Coronary Artery (LCA, LMCA):
  • Circumflex branch (RCX, LCx)
    • Atrioventricular branches
    • Left marginal branch (left marginal artery)
    • Left atrial branch (intermediate artery)
    • Left atrial anastomotic branch (globular artery)
    • Posterior branch of the left ventricle (posterolateral branch)
  • Anterior interventricular branch (LAD, left anterior descending artery)
    • Conus branch
    • Lateral branch (diagonal branch, anterolateral branch)
    • Septal branches (anterior septal branches)
• Right Coronary Artery (RCA):
  • Conus branch
  • Sinoatrial node branch
  • Atrioventricular branches
  • Atrial branches
  • Right marginal branch
  • Posterolateral branch of the right ventricle (RPLD)
  • Atrioventricular node branch
  • Posterior interventricular branch (RPD, right posterior descending artery)
  • Septal branches (posterior septal branches)

This is just one way to classify the coronary artery branches, as individual anatomy often varies depending on the specific type of blood supply to the heart.

Arteria coronaria sinistra

Abbreviations: LCA, LMCA, ACS

The left coronary artery arises from the left aortic sinus, directly behind the attachment of the aortic valve (valvula semilunaris sinistra). In approximately 75 % of cases, it is more pronounced than the right coronary artery. It runs for a short distance between the conus arteriosus and the left aorta and then splits into two main branches, RIVA and RCX.

In the so-called Bland-White-Garland syndrome, the LCA does not originate in the sinus aortae sinister, but from the left pulmonary artery.

Ramus interventricularis anterior

The anterior interventricular ramus (RIVA, LAD) runs caudally in the anterior interventricular sulcus, runs around the apex of the heart (incisura apicis cordis) and anastomoses in the posterior interventricular sulcus with the posterior interventricular ramus of the right coronary artery. It gives off the following branches:

• Ramus coni arteriosi (RCO): to the conus arteriosus
• Ramus lateralis (ramus anterolateralis, ramus diagonalis, RD): to the anterior wall of the left ventricle (many anatomical variations)
• Rami interventriculares septales (Rami septales anteriores, RSA): extend anteriorly into the interventricular septum and supply it via anterior superior, anterior inferior and apical septal branches. There is also a middle main branch area, from which an artery reaches the anterior papillary muscle of the right ventricle via the moderator ligament and supplies it

Ramus circumflexus

The circumflex ramus (RCX, LCx) follows the left side of the coronary sulcus dorsally to the diaphragmatic facies. Its branches are:

• Ramus nodi sinuatrialis: runs on the anterior side of the left atrium to the right atrium and sinus node
  • only fully developed in one third of cases
  • can also branch off from the main branch of the coronary sinus artery
  • is present in two thirds of cases as ramus atrialis (anterior), which supplies the front of the left atrium and anastomoses with the ramus nodi sinuatrialis of the right coronary artery
• Rami atrioventriculares: branch into rami atriales and rami ventriculares sinistri
• Ramus marginalis sinister: runs downwards at the margo obtusus of the left ventricle
• Ramus atrialis intermedius (ramus atrialis sinister): to the back of the left atrium
• Ramus atrialis anastomoticus (globular artery): small branch that anastomoses with branches of the RCA at the atrial level, can also supply the AV node in some cases
• Ramus posterior ventriculi sinistri (ramus posterolateralis sinister): supplies the facies diaphragmatica of the left ventricle

Versorgungsgebiet

The supply area of the left coronary artery includes:

• anterior wall of the left ventricle (RIVA, lateral ramus)
• partially the anterior wall of the right ventricle (ramus coni arteriosi, RIVA)
• anterior two thirds of the ventricular septum (interventricular septal rami)
• left atrium (rami atriales)
• left ventricle: Lateral wall (ramus marginalis sinister), posterior wall (ramus posterior ventriculi sinistri), with the exception of the area surrounding the posterior interventricular sulcus.

Arteria coronaria dextra

Abbreviations: RCA, ACD

The right coronary artery arises from the ascending branch of the aorta, more precisely from the sinus aortae dexter, directly behind the aortic valve. It runs between the conus arteriosus and the right auricle of the heart to the right section of the coronary sulcus. It follows this and then reaches the facies diaphragmatica of the dorsal heart surface. There it gives off its final branch, the posterior interventricular ramus (RIVP, RPD, R-PDA) at the crux cordis (CC), which runs in the posterior interventricular sulcus towards the apex of the heart and anastomoses with the RIVA of the LCA.

Rami

The RCA gives off the following branches:

• Ramus coni arteriosi: supplies the conus arteriosus and parts of the anterior wall of the right ventricle
• Ramus nodi sinuatrialis: runs on the anteromedial side of the right atrium and usually reaches the sinus node via the sulcus terminalis
• Rami atrioventriculares: atrial and ventricular branches; supply anterior sections of the atrium and ventricle
• Rami atriales: supply lateral sections of the right atrium
• Ramus marginalis dexter: runs along the margo acutus of the right ventricle
• Ramus posterolateralis dexter: runs parallel to the ramus marginalis dexter on the back of the right ventricle
• Ramus nodi atrioventricularis: is released shortly before the exit of the ramus interventricularis posterior, runs in the epicardial fatty tissue under the base of the atrial septum forwards to the AV node
• Ramus interventricularis posterior: terminal branch of the RCA, anastomoses with the RIVA of the LCA
• Rami interventriculares septales (Rami septales posteriores): supply the ventricular septum incl. His bundle and sections of the ventricular conduction system
  • anterior superior septal branches: run directly at the exit of the RCA into the upper septum
  • posterior superior and inferior septal branches: branch off from the posterior interventricular ramus

Versorgungsgebiet

The supply area of the right coronary artery includes the following structures:

• Sinus node (ramus nodi sinuatralis)
• AV node (ramus nodi atrioventricularis)
• Right atrium (rami atriales)
• Parts of the posterior wall of the left ventricle (ramus posterolateralis dexter)
• Right ventricle: Anterior wall (rami coni arteriosi, ramus marginalis dexter), lateral wall (ramus marginalis dexter), posterior wall (ramus interventricularis posterior)
• Ventricular septum (interventricular septal rami): smaller posterior part, in which the conduction system (e.g. His bundle) is usually localised

In the clinical context, the full Latin names are rarely used, but mostly abbreviations. English or Latin abbreviations are commonly used.

The exact supply areas of the different coronary arteries and their respective branches are subject to significant variations in some cases. For example, the posterior interventricular ramus can originate from the LCA in 20 % of cases and from both coronary arteries in 10 % (codominant supply type).

In approximately 55 % of cases, an intermediate type (normal supply type) is present: In this case, the posterior wall of the heart is supplied approximately equally from the right and left coronary artery.

In 15 to 20 % of cases, the LCA is even more strongly developed (left supply type): The ramus circumflexus then ends as ramus interventricularis posterior on the posterior wall and supplies parts of the right ventricle in addition to the posterior parts of the interventricular septum.

In the right supply type (15 to 25 % of cases), the right coronary artery and in particular the posterolateral dexter ramus are more strongly developed. The latter then supplies most of the posterior wall of the heart and the ventricular septum.

Trifurcation

Sometimes an additional artery arises at the bifurcation of the left main artery, between the LAD and LCx, creating a trifurcation. This additional branch is called the ramus intermedius. It runs across the free wall of the left ventricle to the apex of the heart and occurs in about 20% of the population.

Single coronary artery

A single coronary artery (SCA) is a rare congenital anomaly. The Lipton classification categorises the various subtypes of this anomaly into three groups:^[1][2].

As the heart is dependent on a continuous supply of oxygen due to its high performance, the functionality of the coronary arteries is crucial for the function of the heart muscle. They therefore form numerous anastomoses with each other. However, these are not sufficient to form a complete collateral circulation (functional end arteries). If a branch is blocked, this leads to ischaemia of the supply area with subsequent necrosis of the heart muscle tissue. With increased cardiac work, it is predominantly metabolites (e.g. CO) of the endothelium that mediate vasodilation of the coronary vessels.

Diseases

The most important disease of the coronary arteries is arteriosclerosis. It leads to coronary stenosis or gradual occlusion of the coronary arteries - a clinical picture known as coronary heart disease (CHD). Clinically, it manifests itself as angina pectoris, heart attack or heart failure. A distinction is made according to the number of coronary vessels affected:

• Single vessel disease,
• Two-vessel disease,
• three-vessel diseases and
• main stem stenoses

Examination methods

The condition of the coronary arteries is usually checked directly by imaging. The exact extent of the narrowing of the coronary arteries can be determined radiographically using coronary angiography as part of a cardiac catheterisation. Indirect indications of coronary perfusion are provided by examination procedures such as ECG or echocardiography. Further diagnostic procedures are

• Cardio-CT
• Cardio-MRI
• Myocardial scintigraphy
• Intravascular ultrasound (IVUS)
• Coronary angioscopy

• Köllner, V. / Berg, G.: Behavioural medicine in the prevention and rehabilitation of cardiovascular diseases. In:Herzmedizin 26 (2009). H.2, PP.69-75.
• Herrmann-Lingen, C.: Depression and coronary heart disease. In: Heart Medicine 26 (2009). H.2, P.76-81.
• Benninghoff, Drenckhahn: Anatomy Volume 2, 16th edition 2004, Elsevier: Urban & Fischer