Safety and Efficacy Continued Access Study of the Medtronic CoreValve® System in the Treatment of Symptomatic Severe Aortic Stenosis in Very High Risk Subjects and High Risk Subjects Who Need Aortic Valve Replacement

Inclusion Criteria

• High Risk: Subject must have co-morbidities such that one cardiologist and two cardiac surgeons agree that predicted risk of operative mortality is ≥15% (and predicted operative mortality or serious, irreversible morbidity risk of 40 mmHg, or jet velocity greater than 4.0 m/sec by either resting or dobutamine stress echocardiogram, or simultaneous pressure recordings at cardiac catheterization (either resting or dobutamine stress), AND
• An initial aortic valve area of ≤ 0.8 cm2 (or aortic valve area index ≤ 0.5 cm2/m2) by resting echocardiogram or simultaneous pressure recordings at cardiac catheterization
• Subject is symptomatic from his/her aortic valve stenosis, as demonstrated by New York Heart Association (NYHA) Functional Class II or greater.
• The subject or the subject's legal representative has been informed of the nature of the trial, agrees to its provisions and has provided written informed consent as approved by the IRB of the respective clinical site.
• The subject and the treating physician agree that the subject will return for all required post-procedure follow-up visits.

Exclusion Criteria

Clinical

• Evidence of an acute myocardial infarction ≤ 30 days before the intended treatment.
• Any percutaneous coronary or peripheral interventional procedure performed within 30 days prior to the MCS TAVI procedure including bare metal and drug eluting stents.
• Blood dyscrasias as defined: leukopenia (WBC 29 mm per the baseline diagnostic imaging (until 23mm valve enrollment completion/closure in the CoreValve® US Pivotal Trial-High Risk Cohort)

OR

Extreme Risk: Native aortic annulus size 29 mm per the baseline diagnostic imaging. (High risk and extreme risk upon 23mm valve enrollment completion/closure in the CoreValve® US Pivotal Trial-High Risk Cohort)

• Pre-existing prosthetic heart valve any position.
• Mixed aortic valve disease (aortic stenosis and aortic regurgitation with predominant aortic regurgitation (3-4+)).
• Moderate to severe (3-4+) or severe (4+) mitral or severe (4+) tricuspid regurgitation.
• Moderate to severe mitral stenosis.
• Hypertrophic obstructive cardiomyopathy.
• Echocardiographic evidence of new or untreated intracardiac mass, thrombus or vegetation.
• Severe basal septal hypertrophy with an outflow gradient.
• Aortic root angulation (angle between plane of aortic valve annulus and horizontal plane/vertebrae) > 70° (for femoral and left subclavian/axillary access) and > 30° (for right subclavian/axillary access).
• Ascending aorta diameter >43 mm if the aortic annulus diameter is 23-29 mm; ascending aortic diameter > 40 mm if the aortic annulus diameter is 20-23 mm; or an ascending aorta diameter > 34 mm if the aortic annulus diameter is 18-20 mm (Extreme Risk only until 23 mm valve enrollment completion/closure in the CoreValve® US Pivotal Trial-High Risk Cohort).
• Congenital bicuspid or unicuspid valve verified by echocardiography.
• Sinus of valsalva anatomy that would prevent adequate coronary perfusion.

Vascular

• Transarterial access not able to accommodate an 18Fr sheath.