Assessing the impact of transcatheter edge-to-edge repair on reverse remodeling in secondary mitral regurgitation: a systematic review and meta-analysis

Background and aim: Transcatheter edge-to-edge repair (TEER) is a minimally invasive approach to reduce secondary mitral regurgitation (SMR) in patients with heart failure. However, there is limited evidence on its effectiveness in achieving reverse remodeling. Our aim was to assess the effects of TEER over time and to compare the effects of TEER plus GDMT vs. GDMT alone on echocardiographic parameters. Methods: A systematic search of MEDLINE, EMBASE, and CENTRAL was conducted from inception to November 16, 2023. Eligible studies included patients with SMR treated with TEER and echocardiographic follow-ups. We evaluated changes in left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left atrial volume (LAV), left ventricular ejection fraction (LVEF) and NTproBNP levels. Results: Of 9,290 identified studies, 38 met inclusion criteria. After TEER, statistically significant reductions were observed in LVEDD (-1.63 mm), LVESD (-1.20 mm), LVEDV (-14.21 mL), and LVESV (-9.24 mL). Changes in LAV (-5.70 mL) and LVEF (+1.10%) were not statistically or clinically meaningful. NT-proBNP decreased substantially (-1,340 pg/mL). In comparative analyses, TEER plus GDMT did not show statistically significant differences vs. GDMT alone for any parameter, including LVEDD (-1.02 mm), LVEDV (-11.98 mL), LVEF (-0.14%), and LVESV (-5.29 mL). TEER reduced grade 3-4 MR from 99% to 9%. Systematic Review Registration: identifier CRD42023483404. Conclusion: TEER results in statistically significant but clinically small changes in echocardiographic parameters, and no clear advantage over GDMT alone. These findings should be interpreted with caution given the high heterogeneity and low certainty of evidence. Further studies are needed to define which SMR patient subgroups may derive meaningful reverse-remodeling benefit from TEER. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=483404, PROSPERO CRD42023483404.