This clinical investigation is being done to evaluate the safety and effectiveness of a new device, a PTV Balloon, that will be used to open up an area in the heart (the valve) before and potentially after placing a new valve in patients requiring a new heart valve.

The main question it aims to answer is:

What percentage of patients develop new heart conduction problems after using the investigational PTV Balloon for pre-dilatation?

Participants will:

1. Undergo a TAVI procedure, where the PTV Balloon will be used for pre-dilatation and may also be used for post-dilatation.
2. Will be followed up until discharge or up to 7 days, whichever happens first.

Inclusion Criteria:

1. Symptomatic severe calcific stenosis of a native aortic valve with an AVA ≤1.0 cm2 (or AVA index ≤0.6 cm2/m2) AND mean aortic pressure gradient ≥ 40mmHg OR maximal transaortic velocity ≥4.0m/s OR Doppler velocity index ≤0.25 on site-reported echocardiography
2. Local multi-disciplinary Heart Team agrees on indication and eligibility for TAVI
3. Age ≥18 years
4. Patient has signed the Patient Informed Consent Form
5. Patient is willing and able to comply with requirements of the study
6. Patients planned for trans-femoral procedure

Exclusion Criteria:

1. Mean aortic annulus diameter as measured by pre-procedural CT or internal diameter of the bioprosthesis is <16 mm or >30 mm
2. Echocardiographic evidence of intracardiac thrombus, mass or vegetation (site-reported)
3. Significant disease of the aorta that would preclude safe advancement of the TAVI system
4. Severe ilio-femoral vessel disease that would preclude safe performance of the TAVI procedure
5. Severe tricuspid regurgitation and/or failing right heart (site-reported)
6. Severe left ventricular dysfunction with ejection fraction (EF) <20% (site-reported)
7. Evidence of active endocarditis or other acute infections
8. Renal failure requiring continuous renal replacement therapy
9. Untreated clinically significant coronary artery disease requiring revascularization
10. Acute MI ≤30 days prior to the index procedure
11. Symptomatic carotid or vertebral artery disease requiring intervention or carotid/vertebral intervention within the preceding 45 days
12. Cerebrovascular accident (CVA) or transient ischemic attack (TIA) ≤6 months or prior CVA with moderate or severe disability (e.g. modified Rankin scale score >2)
13. History of bleeding diathesis or coagulopathy; acute blood dyscrasias as defined: thrombocytopenia (platelets <80,000/µl), acute anemia (hemoglobin <10 g/dl), leukopenia (WBC <3000/ µl)
14. Severe (greater than 3+) mitral insufficiency (site-reported)
15. Known hypersensitivity to contrast media, which cannot be adequately pre-medicated or contraindication to anticoagulant or anti-platelet medication or to nitinol alloy or to bovine tissue
16. Currently participating in another investigational drug or device study
17. Pregnancy or intend to become pregnant during study participation
18. Unicuspid aortic valve
19. Non-calcified aortic stenosis
20. Identified high risk of coronary occlusion due to Sinus of Valsalva anatomy and/or bulky calcified aortic valve leaflets in close proximity to coronary ostia
21. Isolated Aortic Insufficiency
22. Patients with a permanent pacemaker
23. Patients with pre-existing LBBB, RBBB and AV block 2 and 3