A feasibility study to evaluate the effectiveness and safety of the SQ-Kyrin Transcatheter Edge-to-Edge Valve Repair System for the treatment of moderate-to-severe mitral regurgitation in patients with high surgical risk.

This is a prospective, multicenter, single-arm observation, feasibility clinical study that plans to enroll a total of not less than 10 and not more than 30 patients, adopts the post-op immediate technical success rate as the primary endpoint, and uses the all-cause mortality at 30 days post-op, incidence of serious adverse event at 30 days post-op, device success rate at 30 days post-op, and procedural success rate at 30 days post-op as secondary endpoints to evaluate the effectiveness, safety, and feasibility of the Transcatheter Edge-to-Edge Valve Repair System of Shanghai Shenqi Medical Technology Co., Ltd. in clinical use and preliminarily evaluate the product's performance. A phasic study report (for phasic data summary and analysis) will be issued after completion of the 30-day postoperative follow-up to evaluate the effectiveness, safety, and feasibility of the device and apply for clinical studies before official registration and marketing. In the meantime, patients enrolled will continue to be followed up for 6 months and 1-5 years post-op to evaluate the long-term effect of the mitral valve repair system.

Inclusion Criteria:

1. Severe mitral valve regurgitation ≥ 3+ (moderate-to-severe mitral regurgitation disease);

2. Patients with high or prohibitive risk for conventional open thoracic surgery as defined by STS risk scoring result; subjects who are judged as not tolerating mitral valve surgery due to STS procedural mortality risk ≥ 8% for mitral valve replacement or presence of any of the following risk factors:

   1. Porcelain aorta or active ascending aortic atheroma
   2. Prior radiation therapy to mediastinum
   3. History of mediastinitis
   4. Left ventricular ejection fraction (LVEF) < 40%
   5. Presence of unobstructed coronary artery bypass graft
   6. History of 2 or more cardiothoracic surgeries
   7. Liver cirrhosis
   8. Other surgical risk factors

3. Degenerated MR patients, or functional MR patients who have received guideline-directed medical therapy (GDMT therapy)

4. Age ≥ 18 years, male or female;

5. Patients who are at extremely high risk or not suitable for conventional mitral valve surgery, as assessed by a multidisciplinary heart team (including at least one cardiac surgeon and one cardiologist);

6. Anatomically suitable for transcatheter mitral valve repair by edge-to-edge technique and can be treated by the SQ-Kyrin device;

7. Patients who can understand the objectives of the trial, volunteer to participate in the study, sign the informed consent form, and are willing to receive related examinations and clinical follow-up.

Exclusion Criteria:

1. History of cardiac and mitral valve surgeries;
2. Infective endocarditis or evidence of active infection;
3. Mitral valve stenosis;
4. Severe uncontrolled coronary artery disease;
5. Pulmonary artery hypertension (systolic pulmonary artery pressure > 70 mmHg);
6. Severe right cardiac insufficiency;
7. LVEF < 30%;
8. Cardiac function of NYHA Class IV;
9. Patient is extremely week to tolerate surgery under general anesthesia, or in a shock state indicating circulatory support;
10. Hypertrophic cardiomyopathy, restrictive cardiomyopathy, or constrictive pericarditis;
11. Chronic dialysis;
12. Definite coagulation disorder and severe coagulation system diseases;
13. Clear contraindications for use of anticoagulants;
14. Cerebral stroke or transient ischemic attack in the past 30 days;
15. Any cardiac mass, left ventricular or atrial thrombosis identified by echocardiography;
16. Other valve diseases that requiring surgery or intervention;
17. Severe macrovascular disease requiring surgical treatment;
18. Treatment-naive carotid artery stenosis > 70%;
19. Imaging evidence of inappropriate cardiac and valve anatomy;
20. Known hypersensitivity to contrast media, and nickel-titanium memory alloy products;
21. Severe nervous system disorder compromising the cognitive ability;
22. Life expectancy < 12 months;
23. Severe thorax deformity;
24. Pregnant and lactating women.