Pivotal trial to evaluate the safety and effectiveness of the TruGamma tricuspid valve replacement system

The study is a prospective, multi-center, randomized controlled pivotal clinical trial to evaluate the safety and effectiveness of the TruGamma System with optimal medical therapy (OMT) compared to OMT alone in the treatment of patients with at least severe tricuspid regurgitation. Subjects will be followed at discharge, 30 days, 3 months, 6 months and annually through 5 years.

Inclusion Criteria:

1. Age ≥65 years old.
2. The subject must be assessed by the local heart team as a high-risk patient ineligible for surgery and has been stabilized on optimal medical therapy (OMT)（The OMT is evaluated by the local heart team and comprises medications including diuretics with a treatment duration of no less than 30 days; no medication was newly initiated or discontinued within the preceding 2 weeks before treatment, any dose reduction did not exceed 50% of the original dose, and any dose escalation did not exceed 100% of the original dose.）.
3. Despite OMT per the local heart team, patient has signs of TR or symptoms fromTR，and TR graded as at least severe on a TTE(assessedby the 5-grade classification).
4. New York Heart Association (NYHA) Class III-IV.
5. The local heart team determines that the subject's anatomy is appropriate for transcatheter tricuspid valve replacement.
6. Subject is willing and able to comply with all study evaluations and provideswritten informed consent.

Exclusion Criteria:

1. Transesophageal echocardiography (TEE) is contraindicated or cannot be completed.
2. Pulmonary arterial systolic pressure (PASP) >60 mmHg by Dopplerechocardiogram (unless right heart catheterization [RHC] demonstrates PASP ≤60 mmHg).
3. Left ventricular ejection fraction (LVEF) ≤ 25%.
4. Severe aortic, mitral, and/or pulmonic valve stenosis and/or regurgitation requiring surgical intervention.
5. Previous tricuspid surgery or intervention.
6. Patients with congenital Ebstein's anomaly or hypoplastic right ventricle.
7. Patients with right ventricular outflow tract obstruction,or hemodynamically significant pericardial effusion,or significant intracardiac mass, thrombus, or vegetation.
8. Active endocarditis within the last 90 days or infection requiring antibiotictherapy within the last 14 days.
9. Hemodynamic instability with cardiogenic shock or severe hemodynamic compromise, defined as systolic blood pressure (SBP) <90 mmHg with or without vasoactive or afterload-reducing agents, cardiogenic shock , or the need for an intra-aortic balloon pump (IABP), or other mechanical circulatory support (MCS) devices.
10. Patients with respiratory failure who are deemed to be unsuitable candidates for general anesthesia.
11. Severe renal insufficiency with estimated glomerular filtration rate (eGFR) <30mL/min/1.73m2,or requiring chronic renal replacement therapy.
12. Patients with hepatic insufficiency, or cirrhosis with Meld-3.0 score >17.
13. Clinically significant, untreated coronary artery disease requiringrevascularization, recent acute coronary syndrome within the last 30 days.
14. Any major cardiac, coronary, or cervical vascular surgery within the last 30 days.
15. Pacemaker or ICD leads that may interfere with implantation of the tricuspid valve system.
16. Pulmonary embolism in the last 6 months (180 days).
17. Ischemic or hemorrhagic stroke within the last 90 days .
18. Active peptic ulcer disease or upper gastrointestinal bleeding within the last 90 days.
19. Chronic anemia with transfusion dependency or Hgb<90g/L not corrected by transfusion.
20. Thrombocytopenia (platelet count<75,000/mm3) or thrombocytosis (plateletcount >750,000/mm2).
21. Unable to perform the 6-minute walk test (6MWT).
22. Hypersensitivity reaction or known allergy to the raw materials of the investigational device ,or other allergy cannot be adequately managed with medication.
23. Severe Alzheimer's disease.
24. Known contraindication, allergy, or hypersensitivity to BOTH dual antiplatelet therapy AND anticoagulant therapy. A contraindication to either DAPT or anticoagulant therapy alone does not constitute an exclusion criterion.
25. Active malignancy or life expectancy ≤1 year, in the opinion of the investigator.
26. Severe uncontrolled hypertension.
27. Pregnancy, breastfeeding, or a positive pregnancy test at screening, or intention to become pregnant during the study period. (Women with documented history of menopause are exempt.)
28. Concurrent participation in another investigational drug or device clinical trial in which the primary endpoint has not yet been reached.
29. In the opinion of the investigator, the subject is unlikely to comply with study procedures or to complete the study as required.
30. Any other condition or circumstance that, in the judgment of the investigator, would make the subject inappropriate for study enrollment.