Acute kidney injury after aortic valve replacement: incidence, risk factors and outcomes

Abstract

The occurrence of acute kidney injury (AKI) following aortic valve replacement (AVR) has very serious clinical implications and has therefore been the focus of several studies. The authors report the results of previous studies evaluating both transcatheter AVR (TAVR) and indirectly surgical AVR (SAVR) through looking at cardiopulmonary bypass (CPB) cardiac surgeries, and identify the incidence, predictors and outcomes of AKI following AVR. In most studies, AKI was defined using the Risk, Injury, Failure, Loss and End Stage, Valve Academic Research Consortium (modified Risk, Injury, Failure, Loss and End Stage) or Valve Academic Research Consortium-2 (Acute Kidney Injury Network) AKI classification criteria. Twelve studies including more than 90,000 patients undergoing cardiac surgery on CPB were considered as well as 26 studies with more than 6000 patients undergoing TAVR. Depending on the definition used, AKI occurred in 3.4-43% of SAVR cases with up to 2.5% requiring dialysis, and in 3.4-57% of TAVR cases. Factors identified as independent predictors of AKI were: baseline kidney failure, EUROSCORE, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, anemia, peripheral vascular disease, heart failure, surgical priority, CPB time, reoperation, use of intra-aortic balloon pump, need for re-exploration, contrast agent volume, transapical access, blood transfusion, postoperative thrombocytopenia, postoperative leukocytosis as well as demographic variables such as age and female gender. The 30-day mortality rate for patients with AKI following SAVR ranged from 5.5 to 46% and was 3- to 16-times higher than in those without AKI. Similarly, patients who developed AKI after TAVR had a mortality rate of 7.8-29%, which was two- to eight-times higher than those who did not suffer from AKI. AKI confers up to a fourfold increase in 1-year mortality. Finally, hospital length of stay was significantly increased in patients with AKI in both SAVR and TAVR groups, with increases up to 3- and 2.5-times, respectively.

Transcatheter versus surgical aortic valve replacement in intermediate risk patients: a meta-analysis

“…We did, however, find a significant decrease in acute renal failure and an increase in rates of pacemaker implantations in the TAVR group as compared to SAVR group. Although the incidence of acute renal failure has been examined in other trials (21)(22)(23)(24), this is the first instance where a large data set has detected a significant benefit of TAVR over SAVR in a non-high risk population. Our data suggests that TAVR may result in improved neurologic outcomes and reduced post-procedure MIs but this study lacked the power to demonstrate a statistically significant difference.…”

Endovascular aneurysm repair (EVAR)– and transcatheter aortic valve replacement (TAVR)–associated acute kidney injury

“…The mean incidence across studies in the currently available literature for those undergoing SAVR is 33% when using the RIFLE criteria and 26% when using the AKIN criteria. 101 In a recent meta-analysis of twelve studies including >90,000 SAVR patients and 26 studies with >6,000 TAVR patients, AKI occurred in 3.4%-43% of SAVR cases and in 3.4%-57% of TAVR cases, the wide range of incidence 85,107 As in the case of EVAR, the absence of objective information on the volume status of the patients is a limitation of the relevant TAVR literature.…”

Changes in kidney function among patients undergoing transcatheter aortic valve replacement

“…Thus, to date, more than 200 000 TAVR procedures have been performed worldwide (3,10). Despite increasing evidence of treating intermediate surgical-risk patients (7)(8)(9), many patients elected for TAVR commonly have renal insufficiency (11,12), one of important predictors for acute kidney injury (AKI) development (13). In addition, AKI following TAVR is very prevalent, varying from 15% up to 57% (10,11,(14)(15)(16).…”

“…Despite increasing evidence of treating intermediate surgical-risk patients (7)(8)(9), many patients elected for TAVR commonly have renal insufficiency (11,12), one of important predictors for acute kidney injury (AKI) development (13). In addition, AKI following TAVR is very prevalent, varying from 15% up to 57% (10,11,(14)(15)(16). Although patients with chronic kidney disease (CKD) carry a higher risk of developing AKI, improvement in estimated glomerular filtration rate (eGFR) following surgical aortic valve replacements (SAVRs) has been demonstrated in patients with CKD after relief of severe aortic valve diseases (17,18).…”