New markers for early detection of acute kidney injury after transcatheter aortic valve implantation

Early recognition of cardiac surgery-associated acute kidney injury: lack of added value of TIMP2 IGFBP7 over short-term changes in creatinine (an observational pilot study)

Background

For the detection of cardiac surgery-associated acute kidney injury (CS-AKI), the performance of urine tissue inhibitor of metalloproteinase 2 insulin-like growth factor-binding protein 7 (TIMP2 IGFBP7) has never been compared with that of very early changes in plasma creatinine (∆pCr). We hypothesized that, in the context of perioperative haemodilution, lack of postoperative decrease in pCr would be of honourable performance for the detection of CS-AKI. We therefore aimed at comparing these biomarkers and their kinetics (primary objective). As secondary objectives, we assessed plasma neutrophil gelatinase-associated lipocalin (pNGAL), cystatin C (pCysC) and urea (pUrea). We also determined the ability of these biomarkers to early discriminate persistent from transient CS-AKI.

Methods

Patients over 75 years-old undergoing aortic valve replacement with cardiopulmonary bypass (CPB) were included in this prospective observational study. Biomarkers were measured before/after CPB and at the sixth postoperative hour (H6).

Results

In 65 patients, CS-AKI occurred in 27 (42%). ∆pCr from post-CPB to H6 (∆pCr_postCPB-H6): outperformed TIMP2 IGFBP7 at H6 and its intra- or postoperative changes: area under the receiver operating characteristic curve (AUC_ROC) of 0.84 [95%CI:0.73–0.92] vs. ≤0.67 [95%CI:0.54–0.78], p ≤ 0.03. The AUC_ROC of pNGAL, pCysC and pUrea did not exceed 0.72 [95%CI:0.59–0.83]. Indexing biomarkers levels for blood or urine dilution did not improve their performance. Combining TIMP2 IGFBP7 and ∆pCr_postCPB-H6 was of no evident added value over considering ∆pCr_postCPB-H6 alone. For the early recognition of persistent CS-AKI, no biomarker outperformed ∆pCr_postCPB-H6 (AUC_ROC = 0.69 [95%CI:0.48–0.85]).

Conclusions

In this hypothesis-generating study mostly testing early detection of mild CS-AKI, there was no evident added value of the tested modern biomarkers over early minimal postoperative changes in pCr: despite the common perioperative hemodilution in the setting of cardiac surgery, if pCr failed to decline within the 6 h after CPB, the development of CS-AKI was likely. Confirmatory studies with more severe forms of CS-AKI are required.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01387-6.

Performance of Prediction Models for Contrast-Induced Acute Kidney Injury after Transcutaneous Aortic Valve Replacement

BACKGROUND

Acute kidney injury (AKI) has shown to adversely affect outcomes in patients undergoing transcutaneous aortic valve replacement (TAVR), and its correct risk estimation may interfere in procedural planning and strategies. The aim of the study was to test and compare 6 scores in predicting AKI after TAVR.

METHODS

We tested 6 scores (the contrast material limit score, volume-to-creatinine clearance ratio, ACEF, CR4EATME3AD3, Mehran model A, and Mehran model B) in a total of 559 consecutive patients included in the Brazilian TAVR registry.

RESULTS

All scores had a poor accuracy and calibration to predict the occurrence of AKI grade 1 or 2. All scores improved the accuracy of AKI risk prediction when stratified for AKI grade 2/3 and AKI grade 3 for all scores. The CR4EATME3AD3 was the best predictor of AKI stage 2/3 (AUC: 0.62; OR: 1.12; 95% CI 1.01-1.26; p = 0.04) and AKI stage 3 (AUC: 0.64; OR: 1.16; 95% CI 1.02-1.32; p = 0.02). Mehran models A and B were both good models for AKI stage 3 (AUC: 0.63; OR: 1.10; 95% CI 1.01-1.22; p = 0.05; and AUC: 0.62; OR: 1.10; 95% CI 1.00-1.21; p = 0.05, respectively).

CONCLUSIONS

None of the current models demonstrated validity in detecting AKI when its lower grades were evaluated. CR4EATME3AD3 was the best score in predicting moderate to severe AKI after TAVR. These findings suggest that contrast-induced AKI may not be the only factor related to kidney injury after TAVR.

Evaluation and Management of Aortic Stenosis in Chronic Kidney Disease: A Scientific Statement From the American Heart Association

Aortic stenosis with concomitant chronic kidney disease (CKD) represents a clinical challenge. Aortic stenosis is more prevalent and progresses more rapidly and unpredictably in CKD, and the presence of CKD is associated with worse short-term and long-term outcomes after aortic valve replacement. Because patients with advanced CKD and end-stage kidney disease have been excluded from randomized trials, clinicians need to make complex management decisions in this population that are based on retrospective and observational evidence. This statement summarizes the epidemiological and pathophysiological characteristics of aortic stenosis in the context of CKD, evaluates the nuances and prognostic information provided by noninvasive cardiovascular imaging with echocardiography and advanced imaging techniques, and outlines the special risks in this population. Furthermore, this statement provides a critical review of the existing literature pertaining to clinical outcomes of surgical versus transcatheter aortic valve replacement in this high-risk population to help guide clinical decision making in the choice of aortic valve replacement and specific prosthesis. Finally, this statement provides an approach to the perioperative management of these patients, with special attention to a multidisciplinary heart-kidney collaborative team-based approach.

Acute kidney injury after transcatheter aortic valve replacement in the elderly: outcomes and risk management

Aortic stenosis is the most common cause of valve replacement in Europe and North America with prevalence increasing with age. Transcatheter valve replacement (TAVR) represents an alternative for surgical valve replacement of severely stenotic valves. Despite lower risk of acute kidney injury compared to that associated with surgery, this complication remains prevalent in patients undergoing TAVR. There is a paucity of data confirming the relation of acute kidney injury with high morbidity and mortality, especially when superimposed on chronic kidney disease, which is a frequent comorbidity in the elderly with severe aortic stenosis. As there is no consensus on the prevention of acute kidney injury in patients undergoing TAVR, identification and limitation of risk factors are crucial. In this review, we aim to discuss the key aspects of acute kidney injury diagnosis, risk assessment, and outcomes in TAVR patients, and to point out gaps in current knowledge.

Clinical effects of acute kidney injury after transcatheter aortic valve implantation: a systematic review and meta-analysis

Several observational studies have shown that postoperative acute kidney injury (AKI) may significantly worsen the prognosis of a transcatheter aortic valve implantation (TAVI). The purpose of this systematic review and meta-analysis is to evaluate the recent evidence on the impact of AKI on clinical outcomes following TAVI. A comprehensive search in PubMed, Embase and the Cochrane Library was performed for relevant studies by two independent investigators. We pooled the odds ratio (OR) from individual studies, and performed heterogeneity, quality assessment and publication bias analysis. Forty-three eligible studies comprising 544,112 patients were included. Postoperative AKI not only significantly increased the risk for short-term and long-term all-cause mortality (OR 6.25, 95% CI 5.72-6.83, P < 0.00001; OR 3.49, 95% CI 2.78-4.40, P < 0.00001, respectively), but also increased the risk for early myocardial infarction (OR 3.98, 95% CI 1.90-8.31, P = 0.0002), major and life-threatening bleeding (OR 1.51, 95% CI 1.12-2.03, P = 0.007; OR 2.35, 95% CI 1.80-3.06, P < 0.00001, respectively), major vascular complications (OR 1.69, 95% CI 1.30-2.18, P < 0.0001), need for blood transfusion (OR 2.15, 95% CI 1.89-2.46, P < 0.00001) renal replacement therapy (OR 22.36, 95% CI 11.88-42.12, P = 0.0002) and cerebrovascular accidents (OR 1.92, 95% CI 1.23-2.98, P = 0.004). Acute kidney injury following TAVI is associated with increased postoperative mortality and morbidity. Future efforts are required to determine whether early prevention of post-procedural AKI after TAVI impacts upon clinical outcomes.