Clinical Evaluation of MDT-2111 in Subjects With Small Aortic Annuli and Symptomatic Severe Aortic Stenosis

The purpose of this trial is to evaluate the effectiveness and safety of the MDT-2111 TAV system in subjects with small annuli and symptomatic severe AS deemed difficult for surgical intervention. The primary endpoint is a composite of functional effectiveness as measured by improvement of at least 1 New York Heart Association (NYHA) class from baseline to 6 months and anatomical effectiveness as measured by Effective Orifice Area (EOA) ≥1.0 cm² at 6 months.

Inclusion criteria

• Subject must have co-morbidities such that one cardiologist and one cardiac surgeon agree that medical factors preclude operation, based on a conclusion that the probability of death or serious morbidity exceeds the probability of meaningful improvement.
• Subject has senile degenerative aortic valve stenosis with:

mean gradient > 40 mmHg or jet velocity greater than 4.0 m/s 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.

• Subject is symptomatic from his/her aortic valve stenosis, as demonstrated by NYHA Functional Class Class III or greater. If screening committee agrees the eligibility of a patient with class II , based on medical factors, he/she can be enrolled.
• Patient has been informed of the nature of the trial and has signed an Informed Consent Form.
• Patient agrees to comply with specified follow-up evaluations and to return to the same investigational site where the procedure was performed.

Exclusion criteria

• Evidence of an acute myocardial infarction ≤ 30 days prior to the intended treatment.
• Any percutaneous coronary or peripheral interventional procedure performed within 30 days prior to the procedure.
• Blood dyscrasias as defined:

• Leukopenia (WBC count < 1,000 cells/mm³)
• Thrombocytopenia (platelet count <50,000 cells/mm³)
• History of bleeding diathesis or coagulopathy
• Hypercoagulable states
• Untreated clinically significant coronary artery disease requiring revascularization.
• Cardiogenic shock manifested by low cardiac output, vasopressor dependence, or mechanical hemodynamic support.
• Need for emergency surgery for any reason.
• Severe ventricular dysfunction with left ventricular ejection fraction (LVEF) < 20% as measured by resting echocardiogram.
• Recent (within 6 months) cerebrovascular accident (CVA) or transient ischemic attack(TIA).
• End stage renal disease requiring chronic dialysis.
• GI bleeding within the past 3 months.
• A known hypersensitivity or contraindication to any of the following which cannot be adequately pre-medicated:

• Aspirin
• Ticlopidine
• Heparin
• Contrast media
• Nitinol (titanium and nickel alloy)
• Ongoing sepsis, including active endocarditis.
• Subject refuses a blood transfusion.
• Life expectancy < 12 months due to associated non-cardiac co-morbid conditions.
• Other medical, social, or psychological conditions that in the opinion of an Investigator precludes the subject from appropriate consent.
• Severe dementia (resulting in either inability to provide informed consent for the trial/procedure, prevents independent lifestyle outside of a chronic care facility, or will fundamentally complicate rehabilitation from the procedure or compliance with follow-up visits).
• Currently participating in an investigational drug or another device trial. Note: Trials requiring extended follow-up for products that were investigational, but have since become commercially available, are not considered investigational trials.
• Symptomatic carotid or vertebral artery disease.
• Native aortic annulus size < 18 mm or > 20 mm per the screening diagnostic imaging.
• Pre-existing prosthetic heart valve in any position.
• Mixed aortic valve disease (aortic stenosis and aortic regurgitation with predominant aortic regurgitation).
• Mitral regurgitation (moderate to severe) or severe tricuspid regurgitation.
• Moderate to severe mitral stenosis.
• Hypertrophic obstructive cardiomyopathy.
• Echocardiographic evidence of intracardiac mass, thrombus or vegetation.
• Severe basal septal hypertrophy with an outflow gradient.
• Ascending aorta diameter > 34 mm
• Congenital bicuspid or unicuspid valve verified by echocardiography.
• For patients with native coronary artery dependent circulation:

• Sinus of valsalva width < 25 mm OR
• Height of the left or right coronary sinus of valsalva (to the tubular aorta) < 15mm.
• Femoral or iliac artery of the first choice corresponding to any one of the following:

• Angle at aortic root (the angle between aortic valve annulus plane and horizontal plane/vertebra) exceeds 70°.
• Vessel diameter of femoral or iliac artery is less than 6 mm.
• Aorta has severe calcification, excess tortuosity or severe atherosclerosis.
• Transarterial access not able to accommodate an 18Fr sheath.
• Subclavian artery of the second choice corresponding to any one of the following:

• Angle at aortic root (the angle between aortic valve annulus plane and horizontal plane/vertebra) exceeds 70° (in the case of left subclavian artery) and 30° (in the case of right subclavian artery).
• Vessel diameter of subclavian artery is less than 6 mm.
• Transarterial access not able to accommodate an 18Fr sheath.
• Direct Aortic Artery as third line choice of access. Patients are excluded from Direct Aortic access if:

• Access site is less than 6 cm from the aortic valve basal plane
• Access site has calcification or porcelain aorta
• Access site and delivery trajectory contain RIMA or patent RIMA graft