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 outcomes between functional mitral regurgitation (FMR) and degenerative mitral regurgitation (DMR) in patients treated with transcatheter edge-to-edge repair (TEER) using the MitraClip device. MethodsA systematic literature search was conducted in PubMed, Embase, the Cochrane Library, Web of Science, the CNKI, Wanfang Database, VIP Database, and the CBM from their inception to January 2024. Two researchers independently performed study selection, data extraction, and risk of bias assessment. The quality of cohort studies was evaluated using the Newcastle-Ottawa Scale (NOS). A meta-analysis was performed using Stata 18.0 software. ResultsA total of 13 cohort studies involving 6 402 patients were included, comprising 4 161 patients in the FMR group and 2 241 in the DMR group. All included studies had NOS scores of ≥6 points. The meta-analysis revealed that compared to the DMR group, the FMR group had a higher 1-year all-cause mortality rate [OR=1.53, 95%CI (1.30, 1.81), P＜0.01] and a higher 1-year rehospitalization rate for heart failure [OR=1.90, 95%CI (1.60, 2.26), P＜0.01]. Conversely, the FMR group had a lower post-procedural mean transmitral gradient [SMD=–0.47, 95%CI (–0.65, –0.30), P＜0.01] and a lower rate of subsequent mitral valve surgery [OR=0.41, 95%CI (0.20, 0.83), P=0.01]. ConclusionFollowing MitraClip therapy, patients with FMR exhibit favorable short-term outcomes, but their mid- to long-term outcomes are inferior to those of patients with DMR. When determining the treatment strategy with MitraClip, the specific etiology of mitral regurgitation should be considered for a more accurate prediction of therapeutic efficacy and prognosis.