Abstract Body (Do not enter title and authors here): Introduction:
Transcatheter mitral valve repair (TMVR) has recently emerged as a therapy option for patients with severe mitral regurgitation (MR) deemed unsuitable for traditional cardiac surgery. In contrast to surgical mitral valve replacement (SMVr), its effectiveness is uncertain. Therefore, there is a need to assess safety, mortality, and morbidity.

Hypothesis:
To compare the mortality and morbidity of TMVR intervention versus SMVr in patients with MR.

Methods:
Pubmed/Medline, EMBASE, Cochrane, Web of Science, Scopus, and grey literature were searched in May 2022. We only included studies that reported the outcomes of patients undergoing TMVR intervention compared to SMVr for MR, either secondary or primary. The primary outcome was early mortality and major adverse cardiac events (MACE). The secondary outcomes were reoperation rate, long-term survival, and complications. Statistical analysis was performed using R 4.0.3

Results:
Eleven studies comprising 10,627 patients (5307 TMVR and 5320 SMVr) were included in the analysis. In early mortality, the results showed TMVR has a significantly lower mortality rate than SMVr (RR: 0.84; 95% CI, 0.43-1.63; P < 0.01; I2 = 47.8%). MACE was significantly lower in TMVR than SMVr (RR: 0.52; 95% CI, 0.22-1.22; P < 0.01; I2 = 45.1%). Acute kidney injury (AKI) was significantly lower in TMVR compared to SMVr (RR: 0.76; 95% CI, 0. 34-1.67; P < 0.01; I2 = 75.1%). Although not significant, TMVR associatedwith higher rates of reoperation (RR: 2.46; 95% CI, 1.31-4.61; P = 0.53; I2 = 0%). TMVR was associated with non-significant lower rates of bleeding complications and the needs for transfusion (RR: 0.23; 95% CI, 0.20-0.28; P = 0.56; I2 = 0%). However, in long survival outcome, TMVR showed significant higher non-survival rate to SMVr (HR: 1.37; 95% CI, 0.85-2.23; P < 0.01; I2 = 26.1%).

Conclusions:
TMVR showed significantly lower early mortality, MACE, andAKI than SMVr. Long survival outcomes showed a negative trend for TMVR compared to SMVr in a few included studies. Therefore, TMVR can be a safe and effective approach for mitral valve regurgitation with lower early mortality and morbidity when compared to surgical management. However, there is a need for longitudinal studies on long-term outcomes.