Valvuloplasty Scoring Balloon Catheter First-in-Man Study

Inclusion Criteria: * Native, degenerative-calcific, tricuspid, aortic valve stenosis with echocardiographic derived criteria: mean gradient of \>40 mm Hg or Doppler peak systolic velocity greater than 4.0 m/s or an initial aortic valve area \< 0.8 cm2. * Symptomatic aortic valve disease as demonstrated by CCS Functional Class II or greater * Aortic valve annulus of greater than or equal to 18 mm and less than or equal to 28 mm measured on pre-procedure TTE. * Phase 1 patients must be scheduled for a surgical aortic valve replacement. * Phase 2 patients must not be suitable candidates for elective surgical aortic valve replacement. Exclusion Criteria: * Recent myocardial infarction (\<30days) * Unicuspid or bicuspid aortic valve or non-calcific aortic valve stenosis * Any sepsis, including active endocarditis * Concomitant 2+ or greater aortic valve valve regurgitation * LVEF \< 20% * CVA or TIA within the previous 6 months * Previous aortic valve replacement (bioprosthetic or mechanical)