Repair success increases with surgical volume and expertise, which is a principle guiding surgical However, mitral valve replacement is preferable to a poor repair. The results of a mini- mally invasive approach may be similar to those of a full median sternotomy if the minimally inva- sive operation is performed by highly experienced When leaflet dysfunction is limited so that only annuloplasty and repair of the pos- terior leaflet are necessary, an operative mortality rate of <1%, long-term survival rate equivalent to that of the age-matched general population, approximately 95% freedom from reoperation, and >80% freedom from recurrent moderate or severe MR at 15 to 20 years after operation are exp 4. The onset of symptoms, LV dysfunction, or pul- monary hypertension worsens the prognosis for MR. Careful surveillance may result in timing of valve surgery before these negative sequelae occur. However, an attractive alternative strat- egy for treating severe chronic primary MR is to perform early mitral repair before these trig- gers are reached. Early mitral repair avoids the need for intensive surveillance and also obvi- ates the possibility that patients might become lost to follow-up or delay seeing their clini- cian until advanced LV dysfunction has already For the early mitral repair strat- egy to be effective, a durable repair must be provided. An unwanted valve replacement and its attendant risks, or a failed repair necessitat- ing reoperation, could be a complication of this Figure 8. Primary MR. Colors correspond to Table 2. *See Prosthetic Valve section (11.1.2) for choice of mitral valve replacement if mitral valve repair is not possible. CVC indicates Com- prehensive Valve Center; ERO, effective regurgitant orifice; ESD, end-systolic dimension; LVEF, ejection fraction; MR, mitral regurgitation; MV, mitral valve; MVR, mitral valve replacement; RF, regurgitant fraction; RVol, regurgitant volume; and VC, vena contracta. 