Abstract Background Transcatheter Edge-to-edge repair (TEER) using the MitraClip is widely used to treat mitral regurgitation (MR). The evaluation of postprocedural mitral stenosis is important in addition to the reduction of MR. Some papers showed the effect of TEER on mitral valve area (MVA) and mean transmitral pressure gradient (tmPG), but those studies were performed in hospitals in Europe or the United States in the G2 clip era. In addition, the data on the relationship between MVA and mean tmPG is limited. Moreover, the study on the changes of those parameters by TEER in patients other than Europe and the United States is scarce. The current study aims to seek the changes in MVA and mean tmPG by TEER using the MitraClip and the relationship between those parameters in Japanese patients. Methods The patients with significant MR receiving TEER treatment between June 2023 and May 2024 in our hospital were included. The three-dimensional images of mitral valve and mean tmPG were acquired by transesophageal echocardiography (TEE) during the TEER procedure. The MVA before and after clip implantations (MVApre and MVApost) were retrospectively measured using dedicated software (Qlab, Philips). The reduction rate of MVA (change ratio between MVApre and MVApost) compared between degenerative (DMR) and functional MR (FMR), and also examined the relationship between MVApost and mean tmPG after TEER. Results Thirty patients received TEER using the MitraClip in our hospital between June 2023 and May 2024. One patient had two procedures on separate days because of worsening MR and another patient had cardiac surgery during the procedure because of an intraoperative complication. The images during the procedure were inadequate for MVA analysis in one patient. Accordingly, this study included 28 patients who have completed TEER treatment as a first session. Eight and 20 patients were classified as degenerative (DMR) and functional MR (FMR). The MVApre, MVApost, and the reduction rate of MVA were 4.51±1.53cm2, 1.96±0.78cm2, and 55±15%, respectively. The reduction rate of MVApost between DMR and FMR was similar (53±21% and 56±12%, respectively). There was no significant correlation between MVApost and tmPG after TEER even if dividing into two MR groups. However, DMR had a better correlation than FMR. Conclusions The reduction rate of MVA was similar between DMR and FMR. MVApost had no significant association with mean tmPG after TEER. Our study included a small number of patients. Further study is needed to deepen the insight into the relationship between MVA and tmPG.
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