INTRODUCTION: Postoperative acute kidney injury (AKI) and the requirement for renal replacement therapy (RRT) remain common and significant complications of both transcatheter valve-in-valve aortic valve replacement (ViV-TAVR) and redo surgical aortic valve replacement (SAVR). Nevertheless, the understanding of renal outcomes in the population undergoing either redo SAVR or ViV-TAVR remains controversial. METHODS: A systematic database search with meta-analysis was conducted of comparative original articles of ViV-TAVR versus redo SAVR in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to September 2021. Primary outcomes were AKI and RRT. Secondary outcomes were stroke, major bleeding, pacemaker implantation rate, operative mortality, and 30-day mortality. RESULTS: Our search yielded 5435 relevant studies. Eighteen studies met the inclusion criteria with a total of 11,198 patients. We found ViV-TAVR to be associated with lower rates of AKI, postoperative RRT, major bleeding, pacemaker implantation, operative mortality, and 30-day mortality. No significant difference was observed in terms of stroke rate. The mean incidence of AKI in ViV-TAVR was 6.95% (±6%) and in redo SAVR was 15.2% (±9.6%). For RRT, our data showed that VIV-TAVR to be 1.48% (±1.46%) and redo SAVR to be 8.54% (±8.06%). CONCLUSION: Renoprotective strategies should be put into place to prevent and reduce AKI incidence regardless of the treatment modality. Patients undergoing re-intervention for the aortic valve constitute a high-risk and frail population in which ViV-TAVR demonstrated it might be a feasible option for carefully selected patients. Long-term follow-up data and randomized control trials will be needed to evaluate mortality and morbidity outcomes between these 2 treatments.
