Objective To summarize and analyze the preliminary clinical outcomes of the KokaclipTM transcatheter edge-to-edge mitral valve repair system for severe degenerative mitral regurgitation (DMR). Methods This study was a single-arm, prospective, single-group target value clinical trial that enrolled patients who underwent the KokaclipTM transcatheter edge-to-edge repair (TEER) system for DMR in the Department of Heart Surgery of Guangdong Provincial People's Hospital, Guangdong Cardiovascular Institute from June 2022 to January 2023. Differences in the grade of mitral regurgitation (MR) during the perioperative and follow-up periods were compared, and the incidences of adverse events such as all-cause death, thoracotomy conversion, reoperation, and severe recurrence of MR during the study period were investigated. Results The enrolled patient population consisted of 14 (50.0%) females with a mean age of 70.9±5.4 years. Twenty-eight (100.0%) patients were preoperatively diagnosed with typeⅡ DMR, with a prolapse width of 12.5 (11.0, 16.1) mm, a degree of regurgitation 4+ leading to pulmonary venous reflux, and a New York Heart Association cardiac function class≥Ⅲ. All patients completed the TEER procedure successfully, with immediate postoperative improvement of MR to 0, 1+, and 2+ grade in 2 (7.1%), 21 (75.0%), and 5 (17.9%) patients, respectively. Mitral valve gradient was 2.5 (2.0, 3.0) mm Hg. Deaths, thoracotomy conversion, or device complications such as unileaflet clamping, clip dislodgement, or leaflet injury were negative. Twenty-eight (100.0%) patients completed at least 3-month postoperative follow-up with a median follow-up time of 5.9 (3.6, 6.8) months, during which patients had a mean MR grade of 1.0+ (1.0+, 2.0+) grade and a significant improvement from preoperative values (P<0.001). There was no recurrence of ≥3+ regurgitation, pulmonary venous reflux, reoperation, new-onset mitral stenosis, or major adverse cardiovascular events. Twenty-two (78.6%) patients’ cardiac function improved to classⅠorⅡ. Conclusion The domestic KokaclipTM TEER system has shown excellent preliminary clinical results in selected DMR patients with a high safety profile and significant improvement in MR. Additional large sample volume, prospective, multicenter studies, and long-term follow-up are expected to validate the effectiveness of this system in the future.
ObjectiveTo systematically evaluate the differences in efficacy and outcomes between patients with functional mitral regurgitation (SMR) and degenerative mitral regurgitation (DMR) treated with mitral edge-to-edge repair (TEER) using MitraClip. MethodsPubMed, EMbase, the Cochrane Library, Web of Science, China Biomedical Literature Database (CBM), CNKI, Wanfang database, and VIP database were searched in computer. Relevant literature from the database from its establishment to January 2024 was covered. Literature screening, data extraction, and risk of bias assessment for the included studies were performed independently by two researchers. Meta-analysis was performed using Stata18.0 software. ResultsFourteen papers were finally included, including 6 707 patients, including 4 161 patients in the SMR group and 2 241 patients in the DMR group. Meta-analysis results showed that patients in the SMR group had a higher 1-year all-cause mortality rate [OR=1.53, 95%CI (1.30, 1.81), P<0.01, I2=0%] and 1-year readmission rate for heart failure [OR=1.9, 95%CI (1.60, 2.26), P<0.01, I2=0%] after MitraClip treatment than the DMR group patients. Postoperative mitral transvalvular pressure difference [SMD=-0.47, 95%CI (-0.65, -0.30), P<0.01, I2=51%] was lower in patients in the SMR group than in those in the DMR group, and the incidence of subsequent secondary open-heart surgery [OR=0.41, 95%CI (0.20, 0.83), P=0.01, I2=0%] was lower in patients in the SMR group. ConclusionThe results of Meta-analysis showed that after MitraClip treatment, patients in the SMR group showed better efficacy in the short term, but the medium- and long-term efficacy was not as good as that of patients in the DMR group. The specific type of mitral regurgitation should be considered when choosing a MitraClip treatment strategy to more accurately predict efficacy and prognosis.