Investigation of the ALLEGRA THV System With a New Delivery System in Patients With Aortic Stenosis or Failed Surgical Bioprosthesis

Inclusion criteria

• 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 OR symptomatic patients with degeneration of a surgical bioprosthetic valve (stenosis +/- insufficiency) on site-reported echocardiography
• Local multi-disciplinary Heart Team and Central Screening Committee (CSC) agree on indication and eligibility for TAVI
• Age ≥18 years
• Patient has signed the Patient Informed Consent Form
• Patient is willing and able to comply with requirements of the study, including all follow-up visits

Exclusion criteria

General:

• Mean aortic annulus diameter as measured by pre-procedural CT or internal diameter of the bioprosthesis is <16.5 mm or >27 mm
• Echocardiographic evidence of intracardiac thrombus or vegetation (site-reported)
• Significant disease of the aorta that would preclude safe advancement of the ALLEGRA THV System
• Severe ilio-femoral vessel disease that would preclude safe placement of an 18 Fr introducer sheath or make endovascular access impossible
• Porcelain aorta
• Severe left ventricular dysfunction with ejection fraction (EF) <20% (site-reported)
• Evidence of active endocarditis or other acute infections
• Renal failure requiring continuous renal replacement therapy
• Untreated clinically significant coronary artery disease requiring revascularization
• Any percutaneous interventional procedure (e.g. PCI with stenting) within 14 days prior of the index procedure
• Acute MI ≤30 days prior to the index procedure
• Symptomatic carotid or vertebral artery disease requiring intervention or carotid/vertebral intervention within the preceding 45 days
• 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)
• 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)
• Active peptic ulcer or gastrointestinal (GI) bleeding ≤3 months
• Severe (greater than 3+) mitral insufficiency (site-reported)
• Uncontrolled atrial fibrillation
• Required emergency surgery for any reason
• 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
• Life expectancy ≤12 months due to other medical illness
• Currently participating in another investigational drug or device study
• Pregnancy or intend to become pregnant during study participation

Specific exclusions in patients with native aortic valve disease (site-reported):

• Unicuspid or bicuspid aortic valve
• Non-calcified aortic stenosis
• Predominant aortic regurgitation > grade 3
• Distance between native aortic valve basal plane and the orifice of the lowest coronary artery <8 mm

Specific exclusions in patients with degenerated surgical bioprosthetic aortic valves (valve-in-valve) (site-reported):

• Low position of the coronary ostia, especially in combination with shallow sinuses (high risk of coronary occlusion)
• Partially detached leaflets that may obstruct a coronary ostium