Right (anterior) aortic sinus

Aortic sinus

The sinus of Valsalva behind the right cusp of the aortic valve; the ostium of the right coronary artery opens here. Coronary flow to the left ventricle occurs mainly in diastole, because systolic wall tension compresses the intramural vessels.

Detail

Gives rise to
Right coronary artery
Timing of flow
LV perfused mostly in diastole; RV in both phases
Most vulnerable layer
LV subendocardium (highest wall tension, diastole-only flow)
Resting flow
About 250 mL/min (5% of cardiac output)

When it goes wrong

Tachycardia or aortic stenosis shortens diastole and raises LV wall tension

Subendocardial ischaemia and angina without any coronary stenosis

Left coronary artery arising anomalously from the right sinus with an interarterial course

Exertional syncope or sudden cardiac death in a young athlete

Practise this structure

1 question in the bank tagged Coronary Circulation.