Aortic Regurgitation Stages A to D (ACC/AHA)

What the result means

Stage A

At risk: a bicuspid or congenitally abnormal valve, dilated aortic sinuses or root, rheumatic change, or previous endocarditis, with no more than trace regurgitation.

Stage B, mild

Vena contracta below 0.3 cm, regurgitant volume below 30 mL, fraction below 30 percent, orifice below 0.10 square cm.

Stage B, moderate

Vena contracta 0.3 to 0.6 cm, volume 30 to 59 mL, fraction 30 to 49 percent, orifice 0.10 to 0.29 square cm.

Severe

Vena contracta above 0.6 cm, volume 60 mL or more, fraction 50 percent or more, orifice 0.30 square cm or more, with holodiastolic reversal in the proximal descending aorta.

Stage C1

Asymptomatic severe with a compensated ventricle: ejection fraction 55 percent or more AND end-systolic diameter below 50 mm.

Stage C2

Asymptomatic severe with the ventricle giving way: ejection fraction below 55 percent, OR diameter above 50 mm, OR indexed diameter above 25 mm per square meter.

Stage D

Severe regurgitation with symptoms attributable to it.

C2 is a ventricular finding

The regurgitation may be unchanged; what moved is the ventricle. C2 is the line at which an asymptomatic patient is reconsidered, so stopping at the valve misses it.

The indexed route

An indexed diameter above 25 mm per square meter reaches C2 alone. 50 mm in a small body is proportionally far more dilation than 50 mm in a large one.

Read the criteria together

The guideline lists the severity measures as a set, not a ladder where any one wins. Where they disagree, resolve it before acting on the higher grade.