However, in all such series, this predictive ability is not absolute, with 42% of patients with an anatomic valve Wilkins morphol- ogy score >822,23,31,32 having an optimal outcome (25% increase in mitral valve area to >1.5 cm2 ) and 38% of patients with commissural calcium having event-free survival at 1.8 years.18,19,22,23 Accordingly, severely symptomatic patients who are poor surgi- cal candidates may benefit from PMBC even with suboptimal valve anatomy.17 Patients who refuse surgery may also be offered PMBC after discussion about the potential complications associated with this procedure when it is performed in patients with suboptimal valve anatomy. 6.3. Nonrheumatic Calcific MS Recommendation for Nonrheumatic Calcific MS COR LOE Recommendation In severely symptomatic patients (NYHA class III or IV) with severe MS (mitral valve area 1.5 , Stage D) attributable to extensive mitral annular calcification, valve intervention may be considered only after discussion of the high procedural risk and the individual patient s preferences and values.1 3 Synopsis Although most MS in the world results from rheumatic heart disease, calcific MS is found with increasing fre- quency in the elderly population in high-income coun- Calcific MS is the result of calcification of the mitral annulus that extends into the leaflet bases, result- ing both in narrowing of the annulus and rigidity of the leaflets. In contrast to rheumatic MS, there is no commis- sural fusion, and the leaflet tips are usually unaffected. 