Acute Kidney Injury Following Transcatheter Edge-to-Edge Mitral Valve Repair: A Systematic Review and Meta-Analysis

Background: Aim of this study was to perform a systematic review a meta-analysis of the literature in order to identify predictors of acute kidney injury (AKI) in patients with mitral regurgitation (MR) undergoing transcatheter edge-to-edge repair (TEER) and assess its effect on in-hospital outcomes and mortality. Although iodinated contrast is not typically used in TEER, these patients are still at risk for developing AKI. Methods: Studies reporting on the effect of incident AKI on mortality following TEER for MR were included. Random-effects meta-analysis was performed, comparing clinical outcomes between the patients with or without incident AKI. Results: Six studies including a total of 2057 patients (377 AKI and 1680 No-AKI) were included and analyzed. AKI was significantly associated with 30-day mortality after TEER (Odds ratio (OR): 8.06; 95% CI: 3.20, 20.30, p < 0.01; I² = 18.4%) and all-cause mortality over a mean follow-up time of 30 months (Hazard ratio (HR): 2.48; 95% CI: 1.89, 3.24, p < 0.01; I² = 23.7%). AKI after TEER was associated with prolonged hospitalization (Mean difference (in days): 1.41; 95% CI: 0.52, 2.31, p < 0.01; I² = 82.4%). Stage 4 chronic kidney disease (CKD), device failure and history of chronic obstructive pulmonary disease (COPD) were significant predictors of AKI following TEER (CKD stage 4: OR: 2.38; 95% CI: 1.18, 4.78, p = 0.02; I² = 0.0%; Device failure: OR: 3.15; 95% CI: 1.94, 5.12, p < 0.01; I² = 0.0%; COPD: OR: 1.92; 95% CI: 1.16, 3.17; I² = 26.7%). Conclusions: Our findings highlight the renal vulnerability of the TEER population to renal injury and the associated deterioration in clinical outcomes and survival.