Incidence, risk factors and prognostic impact of acute kidney injury after coronary angiography and intervention in kidney transplant recipients: a single-center retrospective analysis

Introduction: Kidney transplant recipients (KTR) represent a high-risk population for cardiovascular disease. Coronary artery disease (CAD) is the most common cause of morbidity and mortality in this population. In KTR, coronary angiography and intervention (CI) can be associated with the risk of acute kidney injury (AKI). Aim: Data about the incidence and impact of AKI after CI in this population are rare. The aim of the present study is to describe the incidence and risk factors of AKI, periprocedural bleeding and the prognostic impact on 1-year mortality in KTR undergoing CI. Material and methods: This retrospective single-center study includes all KTR undergoing CI at University Hospital Frankfurt between 2005 and 2015. Results: A total of 135 CIs in KTR were analyzed. AKI occurred in 31 of 135 CIs (23%, AKI group). Patients of the AKI group were older; other baseline characteristics did not show significant differences. The amount of contrast dye used was higher in the AKI group (p = NS). Periprocedural bleeding defined by BARC criteria occurred more often in the AKI group (23% vs. 5%, p < 0.01) and persisted as a risk factor of AKI in multivariate analysis (odds ratio = 6.43, 95% CI: 1.78-23.20, p = 0.01). In-hospital mortality was 3% in the AKI group; no patient of the non-AKI group died during hospitalization (p = 0.2). One-year-survival was significantly higher in the non-AKI group (94% vs. 81%, p = 0.02). Conclusions: AKI is an important prognostic determinant in KTR undergoing coronary angiography and percutaneous coronary intervention (PCI). Periprocedural bleeding events were associated with AKI. Well-known risk factors for AKI such as contrast agent and diabetes were of minor impact.