Mitral valve training › Guides › Flail leaflet (ruptured chord)

Flail mitral leaflet (ruptured chord) on echocardiography

What to look for: A tip pointing into the LA, a loose chord; a wide wall jet.

Key findings

• A flail leaflet: the tip everts into the LA in systole, often with a ruptured chord moving freely; it is a specific sign of severe MR.
• It is usually a ruptured chord of a degenerative leaflet, most often at P2; after a myocardial infarction, a ruptured papillary muscle causes acute severe MR.
• The jet is eccentric and directed away from the flail leaflet.

Grading the regurgitation (primary MR)

• Severe: vena contracta ≥7 mm, EROA ≥0.40 cm², regurgitant volume ≥60 ml, regurgitant fraction ≥50%. Mild: vena contracta <3 mm, EROA <0.20 cm², regurgitant volume <30 ml.
• Specific signs of severe MR: a flail leaflet or ruptured papillary muscle, a large flow convergence, and systolic flow reversal in the pulmonary veins; a dense, triangular CW signal and an E-wave-dominant inflow support it.
• Integrate several signs: no single measurement grades MR on its own.

Pitfalls

• A small flail segment can be missed in one view: sweep through the parasternal long axis, apical 3-chamber and apical 2-chamber views.
• Eccentric, wall-hugging jets look smaller than they are by colour area (the Coanda effect): rely on the vena contracta, the flow convergence and the other signs.

In the simulator every case varies the anatomy, the jets and the measurements: watch the lesion in Learn, then grade new cases in Practice and compare your answer with the exact one.

Related

Single-scallop prolapse · Barlow disease (bileaflet prolapse) · Endocarditis

Educational simulation to use under the supervision of a clinical tutor — not for clinical use.