Primary Mitral Regurgitation Stages A to D

What the result means

Stage A

At risk: mild prolapse with normal coaptation, mild leaflet thickening, or previous infective endocarditis, with no more than a trivial jet.

Stage B

Progressive: vena contracta below 0.7 cm, regurgitant volume below 60 mL, fraction below 50 percent, orifice below 0.40 square cm.

Severe

Vena contracta 0.7 cm or more, volume 60 mL or more, fraction 50 percent or more, orifice 0.40 square cm or more.

Stage C1

Asymptomatic severe with a compensated ventricle: ejection fraction ABOVE 60 percent AND end-systolic dimension below 40 mm.

Stage C2

Asymptomatic severe with the ventricle giving way: ejection fraction 60 percent or less, OR end-systolic dimension 40 mm or more.

Stage D

Severe regurgitation with symptoms attributable to it.

60 percent, not 50

The leak unloads the ventricle into a low-pressure atrium, so the measured fraction flatters it. A normal value in severe regurgitation is above 60 percent; 55 percent is dysfunction here.

The dimension alone

An end-systolic dimension of 40 mm or more reaches C2 with a preserved ejection fraction. The ventricle dilating is the earlier signal.

Primary only

These criteria are for a problem of the valve itself. Secondary regurgitation, where the valve is normal and the ventricle or atrium has pulled it open, is staged against its own criteria.