Mitral valve training › Guides › Functional MR in a dilated LV (symmetric tethering)
Functional mitral regurgitation in dilated cardiomyopathy on echo
What to look for: A big, weak LV; both leaflets tented; a central jet.
Watch it in the simulator →Practise random casesCarpentier Type IIIb: restricted in systole. Tethering by a remodelled LV (secondary MR). Jet: toward the restricted leaflet, or central. The classification
Key findings
- In a dilated, poorly contracting LV the papillary muscles move apart and outward, tethering both leaflets symmetrically (tenting) with a central jet (type IIIb).
- The annulus dilates too. The regurgitation often improves with heart failure treatment, so reassess it after treatment.
Grading the regurgitation (secondary MR)
- Severe: EROA ≥0.40 cm² or regurgitant volume ≥60 ml; with low flow, EROA ≥0.30 cm² or regurgitant volume ≥45 ml may already be severe.
- The orifice is often crescent-shaped along the coaptation line, so a single PISA can underestimate it.
- Severity changes with loading, rhythm and treatment: grade it on optimal heart failure treatment and note the conditions.
Pitfalls
- A large central jet in a big LA can still be moderate: integrate the vena contracta, the regurgitant volume and the pulmonary vein flow.
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
Ischaemic MR (posterior tethering) · Atrial functional MR
Educational simulation to use under the supervision of a clinical tutor — not for clinical use.