Transcatheter Aortic Valve Implantation in Patients with Chronic Kidney Disease: A Comprehensive Systematic Review and Qualitative Evidence Synthesis

Background Chronic kidney disease (CKD) is prevalent among patients undergoing transcatheter aortic valve implantation (TAVI) and has been associated with adverse clinical outcomes. However, previous systematic reviews have frequently pooled heterogeneous data with varying definitions and methodologies, potentially obscuring clinically meaningful differences. We conducted a comprehensive qualitative systematic review following PRISMA 2020 and Synthesis Without Meta-analysis (SWiM) guidelines to provide a structured synthesis of evidence without statistical pooling. Methods We systematically searched PubMed, Embase, Scopus, and Cochrane Central Register of Controlled Trials from January 2000 through September 2025 for randomized controlled trials and observational studies reporting clinical outcomes after TAVI in adults with CKD. Two independent reviewers performed study selection, data extraction, and quality assessment using the Cochrane Risk of Bias tool for randomized trials and the Newcastle-Ottawa Scale for observational studies. Primary outcomes included all-cause mortality, acute kidney injury (AKI), incident renal replacement therapy (RRT), renal function trajectory, and structural valve deterioration. We synthesized evidence by grouping studies according to outcome and CKD definition, summarizing effect direction and consistency across studies without meta-analysis. Results We identified 18 eligible studies encompassing more than 25,000 participants with CKD undergoing TAVI. The qualitative synthesis demonstrated that CKD was consistently associated with higher short- to intermediate-term mortality (relative risk range: 1.28-1.65 for 30-day mortality) and increased peri-procedural AKI incidence (odds ratio range: 1.89-2.44) compared to patients without CKD. The new RRT requirement was uncommon overall but occurred more frequently in CKD patients, particularly those with advanced disease. Despite higher procedural risks, multiple studies reported that the majority of CKD patients experienced stable or improved renal function post-TAVI, while early renal deterioration was a strong predictor of subsequent mortality. Comparative data showed no clear difference in structural valve deterioration between CKD and non-CKD patients over mid-term follow-up (≤5 years). Risk of bias was generally moderate for observational studies, while randomized trial subgroup analyses demonstrated lower risk of bias. Sensitivity analyses stratified by CKD definition and valve generation supported the robustness of these findings. Conclusions This qualitative evidence synthesis indicates that while CKD confers elevated peri-procedural and mid-term risks following TAVI, particularly for mortality and AKI, renal function commonly stabilizes or improves post-procedure. These findings support the appropriateness of TAVI in carefully selected CKD patients, with emphasis on implementing renal-protective strategies and structured long-term follow-up protocols.