The purpose of this trial is to determine the safety and effectiveness of the Edwards SAPIEN 3 transcatheter heart valve and delivery systems which are intended for use in patients with symptomatic, calcific, and severe aortic stenosis, and those with intermediate risk.

This study design consists of PIIS3i cohort.

The PIIS3i cohort is a single arm non-randomized, historical-controlled study. Patients recruited to the treatment arm will receive an Edwards SAPIEN 3 THV with either transfemoral, transapical or transaortic delivery access.

To ensure that patients are of "intermediate" risk, an STS score of 4 - 8% has been selected.

Inclusion Criteria

1. Patient has senile degenerative aortic valve stenosis with echocardiographically derived criteria: mean gradient >40 mmHg or jet velocity greater than 4.0 m/s and an initial aortic valve area (AVA) of <0.8 cm2 or indexed EOA < 0.5 cm2/m2 Qualifying echo must be within 60 days of the date of the procedure.
2. Patient is symptomatic from his/her aortic valve stenosis, as demonstrated by NYHA Functional Class II or greater.
3. The heart team agrees (and verified in the case review process) that valve implantation will likely benefit the patient.
4. The study patient or the study patient's legal representative has been informed of the nature of the study, agrees to its provisions and has provided written informed consent as approved by the Institutional Review Board (IRB) of the respective clinical site.
5. The study patient agrees to comply with all required post-procedure follow-up visits including annual visits through 5 years and analysis close date visits, which will be conducted as a phone follow-up.

Exclusion Criteria:

1. Heart team assessment of inoperability (including examining cardiac surgeon).

2. Complex coronary artery disease

   1. Unprotected left main coronary artery
   2. Syntax score > 32 (in the absence of prior revascularization)

3. Hemodynamic or respiratory instability requiring inotropic support, mechanical ventilation, or mechanical heart assistance within 30 days of screening evaluation.

4. Need for emergency surgery for any reason.