Synopsis
Separate primary from secondary and acute from chronic mitral regurgitation, quantify severity, and direct patients to repair, replacement or transcatheter treatment at the right time.
- Primary MR is a disease of leaflets/chordae, commonly prolapse or flail; secondary MR results from LV or atrial remodelling with initially normal leaflets.
- A pansystolic apical murmur radiating to the axilla is typical, but acute severe MR can have a short or quiet murmur because LA pressure rises rapidly.
- Severe primary MR is supported by an integrated echo assessment, often including EROA at least 0.40 cm2 or regurgitant volume at least 60 mL/beat.
Key red flags
Abrupt breathlessness, pulmonary oedema, hypotension or shock after MI, endocarditis or chordal rupture may occur with a unimpressive murmur.
Investigation priorities
Define mechanism, severity, LV/LA size, LVEF, pulmonary pressure and other valve disease.
Management branches
Abrupt severe MR causes pulmonary oedema, hypotension or shock.
- Use ABCDE care, continuous monitoring and oxygen/ventilatory support for hypoxaemia; call cardiology, critical care and cardiac surgery immediately.
- Obtain urgent TTE and usually TOE, while investigating MI, papillary-muscle/chordal rupture and endocarditis; take cultures promptly when infection is possible.
Key medicines
FurosemideFor chronic oedema, 40 mg orally in the morning is a usual initial adult dose; maintenance is often 20 mg daily or 40 mg on alternate days. For acute oedema, the injection SmPC gives 20–50 mg IV initially, at no faster than 4 mg/min.
RamiprilFor stable symptomatic heart failure, start 1.25 mg orally once daily and double at 1–2-week intervals as tolerated to a maximum 10 mg/day, preferably in two divided doses; for hypertension, a usual start is 2.5 mg once daily.