Mitral valve repair
The leaking mitral valve is reshaped so the patient keeps their own valve.
Why it's done
- Severe primary (degenerative) mitral regurgitation with symptoms.
- Severe primary MR without symptoms but with early LV dysfunction or dilation, new AF or pulmonary hypertension, especially when a durable repair is very likely.
- Repair beats replacement for degenerative MR when it can be done well, so these patients should go to experienced repair surgeons.
The steps
- Approach: Median sternotomy, or a right mini-thoracotomy with video or robotic assistance in specialist centres.
- Open the left atrium: Bypass and arrest, then a left atriotomy (often through Sondergaard's groove) exposes the valve.
- Analyse the valve: Saline is injected into the ventricle to show where it leaks. The lesion is classified using Carpentier's types.
- Fix the leaflets: A prolapsing segment is either resected (classically a triangular or quadrangular resection of P2) or held down with artificial chords made of ePTFE ('neochords'). The surgeon's motto is often 'respect rather than resect'.
- Annuloplasty: A ring or band is always sewn around the annulus to reshape it and protect the repair.
- Test: Saline testing in theatre, then TOE after coming off bypass to confirm no significant leak and no SAM.
Risks
- Residual or recurrent mitral regurgitation
- Systolic anterior motion (SAM) causing LV outflow obstruction
- Atrial fibrillation
- Bleeding
- Later need for replacement
Recovery
Like other valve surgery. Minimally invasive approaches can mean less pain and a quicker return to normal, though the operation inside the heart is the same.
St George's Cardiothoracic Surgery Society, City St George's, University of London.