Abstract:

Objective To evaluate the safety and efficacy of transcatheter mitral valve-in-valve replacement (ViV-TMVR) in the treatment of bioprosthetic mitral valve failure. Methods Seventeen patients with bioprosthetic mitral valve failure who required ViV-TMVR were selected. Preoperative data including age, gender, body mass index (BMI), usage time of bioprosthetic mitral valve, comorbidities (hypertension, coronary heart disease, old cerebral infarction, atrial fibrillation and diabetes) and New York Heart Association (NYHA) functional class were recorded, and left ventricular end-diastolic diameter (LVEDD), right atrial diameter (RA), pulmonary artery systolic pressure (PASP), left ventricular ejection fraction (LVEF), type of bioprosthetic mitral valve failure, degree of bioprosthetic mitral valve regurgitation and stenosis, peak velocity and mean transvalvular pressure gradient of the bioprosthetic mitral valve, and Society of Thoracic Surgeons (STS) score were also collected. Intraoperative data included puncture route, valve type, intraoperative complications, operation time and immediate postoperative transesophageal echocardiography (TEE) assessment (peak velocity and mean transvalvular pressure gradient of the valve-in-valve, valve-in-valve regurgitation or paravalvular regurgitation) were collected. Postoperative data included time in the intensive care unit (ICU)/cardiovascular intensive care unit (CCU), total postoperative hospital stay and 30-day postoperative echocardiographic results and NYHA functional class were recorded. Patients were divided into the domestic NewMed valve group (10 cases) and the imported Edwards valve group (7 cases) based on the type of valve used. The safety and efficacy of ViV-TMVR were analyzed, and the efficacy of domestic valves and imported valves was compared. Results All 17 patients successfully underwent ViV-TMVR via the transseptal approach without serious complications, and the 30-day readmission rate was 0%. There were no significant differences in operation time of domestic valves and imported valves, mild paravalvular regurgitation of the valve-in-valve, peak velocity and mean transvalvular pressure gradient of the valve-in-valve immediately after surgery and at 30-day postoperatively, time in ICU/CCU, total postoperative hospital stay and the proportion of patients with NYHA functional class Ⅲ-Ⅳ at 30-day postoperatively between the domestic valve group and the imported valve group. During the 30-day follow-up, one patient died of cerebral hemorrhage, and one patient had major adverse cardiovascular events (MACE, cerebral hemorrhage). Compared with before the operation, the peak velocity and mean transvalvular pressure gradient of the valve-in-valve, LVEF, and PASP decreased immediately after surgery and at 30 days after surgery. Compared with immediately after surgery, the peak velocity and mean transvalvular pressure gradient of the valve-in-valve increased at 30 days postoperatively (P < 0.01), while there were no significant differences in LVEF and PASP. Conclusion Transseptal ViV-TMVR is safe and effective in the short term for patients with bioprosthetic mitral valve failure who are at high risk of re-thoracotomy, and the efficacy of domestic valves is comparable to that of imported valves.

Key words: mitral valve, heart valve diseases, heart valve prosthesis implantation, atrial septum, catheters, bioprosthetic mitral valve failure, "valve-in-valve" replacement