Right and left coronary arteries

Branch · Aortic sinuses Diastolic filling

Right coronary from the anterior (right) aortic sinus and left coronary from the left posterior sinus; the only branches of the ascending aorta. They fill mainly in diastole, when the closed cusps no longer obstruct the sinus openings.

Traced from the start

  1. Ascending aorta
  2. Right and left coronary arteries

Detail

Right coronary
Runs in the right atrioventricular groove; gives the SA nodal artery in about 60% and the posterior interventricular artery in about 85% (right dominance), and so the AV nodal artery
Left coronary
Short left main divides into the left anterior descending (anterior interventricular) and the circumflex
Supplies
Myocardium and the conducting system

When it goes wrong

Occlusion of the right coronary artery

Inferior STEMI (II, III, aVF) with sinus bradycardia and AV block from loss of the SA and AV nodal arteries; right ventricular infarction makes the patient hypotensive with nitrates

Occlusion of the left anterior descending artery

Anterior STEMI (V1–V4) with the highest risk of cardiogenic shock and ventricular septal rupture

Practise this structure

1 question in the bank tagged Coronary Circulation.