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Mechanical mitral valve on echo: normal washing jets and leaks

What to look for: Bright discs and a shadow over the LA; small washing jets at the pivots are normal.

Key findings

• A bileaflet mechanical valve: two bright discs that open almost parallel, with reverberation artefacts and a shadow over the LA in apical views.
• Washing jets are normal: small, narrow at the origin and uniform in colour, at the hinges and between the discs. They are built-in leakage that keeps the hinges from clotting. A pathological leak is larger, eccentric and turbulent.
• Disc motion is best seen by TOE or fluoroscopy; a restricted disc suggests thrombus or pannus. Describe paravalvular leaks on the surgical (atrial) view as a clock face, with the aortic valve at 12 o’clock and the LA appendage at 9 o’clock.

Grading prosthetic function

• Normal mitral prosthesis: peak E <1.9 m/s, mean gradient ≤5 mmHg, VTI ratio (prosthesis / LVOT) <2.2, effective orifice area ≥2.0 cm², PHT <130 ms. Significant stenosis is suggested by peak E ≥2.5 m/s, mean gradient >10 mmHg, VTI ratio >2.5, orifice area <1.0 cm² and PHT >200 ms; the call is surest when most of them agree.
• Report the heart rate: a fast rate, high flow and patient–prosthesis mismatch also raise the velocities and gradient, and some bioprostheses run slightly higher.
• In a mechanical valve, high velocities with a normal PHT (<130 ms) point to significant MR hidden in the acoustic shadow, not to stenosis: peak E ≥1.9 m/s, VTI ratio ≥2.5 and mean gradient ≥5 mmHg. With both the velocity and the VTI ratio raised, specificity is close to 100%; flow convergence on the LV side is specific but often not seen.
• Grade valvular and paravalvular regurgitation alike: jet size and origin, flow convergence, CW density, pulmonary vein flow and LV size, often best seen with TOE.

Pitfalls

• The prosthesis shadows the LA in apical views and can hide a jet: TOE shows it.

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

Edge-to-edge repair (TEER clip) · Surgical repair (annuloplasty ring) · Bioprosthetic mitral valve

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