The risk of acute kidney injury following transapical versus transfemoral transcatheter aortic valve replacement: a systematic review and meta-analysis

Incidence, severity, risk factors and outcomes of acute kidney injury in older adults: systematic review and meta-analysis

OBJECTIVES

Old age was identified as a strong risk factor for acute kidney injury (AKI). Our objectives were to provide estimates of AKI, risk factors and outcomes in patients ≥ 75 years for whom data are scarce.

METHODS

Observational studies and randomized controlled trials between 2005 and 2021 with patients of mean or median age ≥ 75 years, reporting AKI according to current definitions. Data on AKI incidence, risk factors and mortality were analyzed separately in unselected (UC) and acute heart failure (AHF) cohorts.

RESULTS

Twenty-six observational studies and 4 randomized controlled trials with 51,111 UC and 25,414 AHF patients were included. Ages averaged 79.4 and 79.8 years, respectively. Pooled risk ratios (RRs) of AKI rates were 26.29% (95% confidence intervals (CI) 13.20-41.97) (UC) and 24.21% (95% CI 20.03-28.65) (AHF). In both cohorts, AKI was associated with decreased estimated glomerular filtration rate at baseline, chronic kidney disease (UC: RR 1.80 (95% CI 1.15-2.80), AHF: RR 1.51 (95% CI 1.26-1.95) and hypertension (UC: RR 1.30 (95% CI 1.09-1.56), AHF: RR 1.07 (95% CI 1.05-1.09). RRs of AKI in patients on renin-angiotensin-inhibitors were 0.87 (95% CI 0.78-0.97) and 0.88 (95% CI 0.78-0.98) in UC and AHF, respectively. AKI was consistently associated with increased risk of in-hospital mortality (UC: RR 3.15 (95% CI 2.28-4.35), AHF: RR 4.28 (95% CI 2.53-7.24).

CONCLUSION

AKI is frequent in patients ≥ 75 years. While reduced renal function at baseline, CKD and hypertension were associated with AKI development, renin-angiotensin-inhibitors may be protective. Older AKI patients showed higher short-term mortality rates.

Effect of TAVR Approach and Other Baseline Factors on the Incidence of Acute Kidney Injury: A Systematic Review and Meta-Analysis

Background

Acute kidney injury (AKI) is a well-known complication following a transcatheter aortic valve replacement (TAVR) and is associated with higher morbidity and mortality.

Objective

We aim to compare the risk of developing AKI after transfemoral (TF), transapical (TA), and transaortic (TAo) approaches following TAVR.

Methods

We searched Medline and EMBASE databases from January 2009 to January 2021. We included studies that evaluated the risk of AKI based on different TAVR approaches. After extracting each study's data, we calculated the risk ratio and 95% confidence intervals using RevMan software 5.4. Publication bias was assessed by the forest plot.

Results

Thirty-six (36) studies, consisting of 70,406 patients undergoing TAVR were included. Thirty-five studies compared TF to TA, and only seven investigations compared TF to TAo. AKI was documented in 4,857 out of 50,395 (9.6%) patients that underwent TF TAVR compared to 3,155 out of 19,721 (16%) patients who underwent TA-TAVR, with a risk ratio of 0.49 (95% CI, 0.36–0.66; p < 0.00001). Likewise, 273 patients developed AKI out of the 1,840 patients (14.8%) that underwent TF-TAVR in contrast to 67 patients out of the 421 patients (15.9%) that underwent TAo-TAVR, with a risk ratio of 0.51 (95% CI, 0.27–0.98; p = 0.04). There was no significant risk when we compared TA to TAo approaches, with a risk ratio of 0.89 (95% CI, 0.29–2.75; p = 0.84).

Conclusion

The risk of post-TAVR AKI is significantly lower in patients who underwent TF-TAVR than those who underwent TA-TAVR or TAo-TAVR.

Chronic kidney disease and transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is an established treatment option for patients with severe aortic stenosis. Patients with aortic stenosis have a higher prevalence of chronic kidney disease (CKD). CKD is generally associated with an increased risk of mortality, cardiovascular events, and readmission for heart failure; this supports the concept of a cardio-renal syndrome (CRS). CRS encompasses a spectrum of disorders of the heart and kidneys, wherein dysfunction in one organ may cause dysfunction in the other. TAVI treatment is expected to break this malignant cycle of CRS and improve cardio-renal function after the procedure. However, several reports demonstrate that patients with CKD have been associated with poor outcomes after the procedure. In addition, TAVI treatments for patients with advanced CKD and those with end-stage renal disease on hemodialysis are considered more challenging. Adequate management to preserve cardio-renal function in patients undergoing TAVI may reduce the risk of cardio-renal adverse events and improve the long-term prognosis. The current comprehensive review article aims to assess the prognostic impact of CKD after TAVI and seek optimal care in patients with CKD even after successful TAVI.

Alternate accesses for transcatheter aortic valve replacement: A network meta-analysis

BACKGROUND

When transfemoral (TF) access is contraindicated in patients undergoing transcatheter aortic valve replacement (TAVR), alternate access strategies are considered. The choice of one alternate access over the other remains controversial.

METHODS

Following a comprehensive literature search, studies comparing any combination of TF, transapical (TA), transaortic (TAo), transcarotid (TC), and trans-subclavian (TS) TAVR were identified. Data were pooled using fixed- and random-effects network meta-analysis. Rank scores with probability ranks of different treatment groups were calculated.

RESULTS

Eighty-four studies (26,449 patients) were included. Compared to TF access, TA and TAo accesses were associated with higher 30-day mortality (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.31-1.94; OR 1.79, 95% CI 1.21-2.66, respectively), while the TC and TS showed no difference (OR 1.12, 95% CI 0.64-1.95; OR 1.23, 95% CI 0.67-2.27, respectively); TF access ranked best followed by TC. There was no significant difference in 30-day stroke; TC access ranked best followed by TS. At a weighted mean follow-up of 1.6 years, TA and TAo accesses were associated with higher long-term mortality versus TF (incidence rate ratio [IRR] 1.31, 95% CI 1.18-1.45; IRR 1.41, 95% CI 1.11-1.79, respectively); there was no difference between TC and TS versus TF access (IRR 1.02, 95% CI 0.70-1.47; IRR 1.16, 95% CI 0.82-1.66, respectively); TF access ranked best followed by TC. At a weighted mean follow-up of 1.4 years, only TA access was associated with higher long-term stroke compared to TF (IRR 3.01, 95% CI 1.15-7.87); TF access ranked as the best strategy followed by TAo.

CONCLUSION

TC and TS approaches are associated with superior postoperative outcomes compared to other TAVR alternate access strategies. Randomized trials definitively assessing the safety and efficacy of alternate access strategies are needed.

Late kidney injury after transcatheter aortic valve replacement

BACKGROUND

Information on early to late-phase kidney damage in patients who underwent transcatheter aortic valve replacement (TAVR) is scarce. We aimed to identify the predictive factors for late kidney injury (LKI) at 1-year and patient prognosis beyond 1-year after TAVR.

METHODS

We retrospectively reviewed 1,705 patients' data from the Japanese TAVR multicenter registry. Acute kidney injury (AKI) and LKI, defined as an increase of at least 0.3 mg/dL in creatinine level, a relative 50% decrease in kidney function from baseline to 48 hours and 1-year, were evaluated. The patients were categorized into the 4 groups as AKI-/LKI- (n = 1.362), AKI+/LKI- (n = 95), AKI-/LKI+ (n = 199), and AKI+/LKI+ (n = 46).

RESULTS

The cumulative 3-year mortality rates were significantly increased across the four groups (12.5%, 15.8%, 24.6%, 25.8%, P < .001). Multivariate analysis revealed that chronic kidney disease, coronary artery disease, periprocedural AKI, and heart failure-related re-admission within 1-year were significantly associated with LKI. The Cox regression analysis revealed that AKI-/LKI+ and AKI+/LKI+ were independent predictors of increased late mortality beyond 1-year after TAVR (P = .001 and P = .01).

CONCLUSIONS

LKI was influenced by adverse cardio-renal events and was associated with increased risks of late mortality beyond 1-year after TAVR.

Minimizing Paravalvular Regurgitation With the Novel SAPIEN 3 Ultra TAVR Prosthesis: A Real-World Comparison Study

Objectives: We investigated performance and outcome of the latest-generation balloon-expandable SAPIEN 3 Ultra prosthesis (S3U) compared to the established SAPIEN 3 prosthesis (S3) in a real-world cohort, with focus on paravalvular regurgitation (PVR).

Background: PVR is an adverse prognostic indicator of short- and long-term survival after transcatheter aortic valve replacement (TAVR). The S3U has been designed to improve sealing.

Methods: We enrolled 343 consecutive patients presenting with severe native aortic valve stenosis eligible for a balloon-expandable prosthesis. The established S3 was implanted in the first 200 patients, the following 143 patients received the novel S3U after introduction in our institution. Primary endpoint was PVR after TAVR. Furthermore, we investigated procedural parameters and in-hospital and 30-day outcome.

Results: PVR was significantly lower in the S3U cohort compared to the S3 cohort. They differed in their rate of mild PVR (11.2 vs. 48.0%, p < 0.001), whereas at least moderate PVR was similarly low in both cohorts (0.7 vs. 0.5%, p = 0.811). A significant reduction of post-dilatation rate, fluoroscopy time, and amount of contrast was observed in patients treated with the novel S3U (p < 0.001). The rate of adverse events in the in-hospital course and at 30 days were similarly low. At 30 days more patients receiving S3U improved in NYHA class (improvement ≥2 grades 34.6 vs. 19.9%, p = 0.003).

Conclusion: The current study provides evidence that the novel S3U strongly minimizes PVR, thereby demonstrating the efficacy of improved sealing. Further studies will have to address if the observed reduction of PVR with S3U has prognostic significance.

Minimally invasive surgery versus transcatheter aortic valve replacement: a systematic review and meta-analysis

Transcatheter aortic valve replacement (TAVR) has recently been approved for use in patients who are at intermediate and low surgical risk. Moreover, recent years have witnessed a renewed interest in minimally invasive aortic valve replacement (miAVR). The present meta-analysis compared the outcomes of TAVR and miAVR in the management of aortic stenosis (AS). We conducted an electronic search across six databases from 2002 (TAVR inception) to December 2019. Data from relevant studies regarding the clinical and length of hospitalisation outcomes were extracted and analysed using R software. We identified a total of 11 cohort studies, of which seven were matched/propensity matched. Our analysis demonstrated higher rates of midterm mortality (≥1 year) with TAVR (risk ratio (RR): 1.93, 95% CI: 1.16 to 3.22), but no significant differences with respect to 1 month mortality (RR: 1.00, 95% CI: 0.55 to 1.81), stroke (RR: 1.08, 95% CI: 0.40 to 2.87) and bleeding (RR: 1.45, 95% CI: 0.56 to 3.75) rates. Patients undergoing TAVR were more likely to experience paravalvular leakage (RR: 14.89, 95% CI: 6.89 to 32.16), yet less likely to suffer acute kidney injury (RR: 0.38, 95% CI: 0.21 to 0.69) compared with miAVR. The duration of hospitalisation was significantly longer in the miAVR group (mean difference: 1.92 (0.61 to 3.24)). Grading of Recommendations Assessment, Development and Evaluation assessment revealed ≤moderate quality of evidence in all outcomes. TAVR was associated with lower acute kidney injury rate and shorter length of hospitalisation, yet higher risks of midterm mortality and paravalvular leakage. Given the increasing adoption of both techniques, there is an urgent need for head-to-head randomised trials with adequate follow-up periods.

Kidney dysfunction and short term all-cause mortality after transcatheter aortic valve implantation

BACKGROUND

Acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) has been associated with worse outcomes. However, the impact on outcome of AKI in TAVI-patients is not well established.

METHODS

Inoperable patients with severe aortic stenosis (AS) undergoing TAVI in 2010-2018 were enrolled in this study. AKI and chronic kidney disease (CKD) were defined according to KDIGO guidelines. Patients were divided in two groups according to post-procedural AKI development. The primary endpoint was 30-day all-cause mortality across the two groups.

RESULTS

A total of 373 patients (mean age 82.3 ± 6) were analyzed. Compared to non-AKI patients, those who developed AKI, were treated more frequently with trans-apical TAVI (66% vs 35%, p<0.01), with greater amount of contrast medium (200.6 vs 170.4 ml, p=0.02) and in presence of clinically significant peripheral artery disease (PAD, 33% vs 21%, p=0.04). Trans-apical access (OR 3.24, 95% CI 1.76-5.60, p<0.01) was associated with a 3-fold risk of AKI. After adjustment for age, Society of Thoracic Surgery risk score (STS), PAD, access type, EF and contrast medium amount, patients with AKI presented an increased risk of 30-day all-cause mortality (HR=1.25, 95%CI 1.09-1.69, p=0.008). Patients with CKD IV and V, who developed AKI, presented a 9-fold 30-day mortality risk (HR=9.71, 95% CI 2.40-39.2, p=0.001).

CONCLUSION

In our analysis, AKI was a strong predictor of 30-day all-cause mortality. Particularly, patients with severe CKD with AKI showed the highest 30-day mortality risk. Thus, this group of patients might benefit from closer monitoring and specific kidney protection therapies.

Late Adverse Cardiorenal Events of Catheter Procedure-Related Acute Kidney Injury After Transcatheter Aortic Valve Implantation

Data regarding the longitudinal effect of catheter procedure-related acute kidney injury (AKI) on clinical outcomes are limited. This study aimed to assess the late adverse cardiorenal events of AKI following transcatheter aortic valve implantation (TAVI). A total of 2,518 patients who underwent TAVI, excluding in-hospital deaths, were enrolled from the Japanese multicenter registry. The definition of AKI was determined using the Valve Academic Research Consortium-2 criteria. The incidence, predictors, major adverse renal and cardiac events (MARCE), and all-cause mortality of AKI were evaluated. MARCE included readmission for renal and heart failure (HF), hemodialysis requirement, and cardiovascular-renal death during the follow-up period. The incidence of AKI was 9.7% in the entire cohort. The significant predictive factors of AKI were men, diabetes mellitus, hypertension, chronic kidney disease, low albumin, overdose of contrast media, nontransfemoral approach, transfusion, vascular complications, and new pacemaker implantation. The rates of HF readmission and future hemodialysis were significantly higher in patients with AKI than in those without AKI (19.7% vs 9.0%, p <0.001, 3.3% vs 0.4%, p <0.001, respectively). Cox regression multivariate analysis showed that AKI occurrence was an independent predictive factor for the incremental risk of both MARCE and late mortality up to 4 years (hazard ratio [HR] 1.59, 95% confidence interval [CI] 0.75 to 1.20, p <0.001, HR 2.18, 95% CI 1.70 to 2.79; p <0.001, respectively). In conclusion, AKI occurrence was significantly associated with late adverse cardiorenal events after TAVI. Adequate clinical management can be expected to reduce AKI-related late phase cardiorenal damage even after successful TAVI.

Predicting Acute Kidney Injury after Cardiac Surgery by Machine Learning Approaches

Cardiac surgery-associated AKI (CSA-AKI) is common after cardiac surgery and has an adverse impact on short- and long-term mortality. Early identification of patients at high risk of CSA-AKI by applying risk prediction models allows clinicians to closely monitor these patients and initiate effective preventive and therapeutic approaches to lessen the incidence of AKI. Several risk prediction models and risk assessment scores have been developed for CSA-AKI. However, the definition of AKI and the variables utilized in these risk scores differ, making general utility complex. Recently, the utility of artificial intelligence coupled with machine learning, has generated much interest and many studies in clinical medicine, including CSA-AKI. In this article, we discussed the evolution of models established by machine learning approaches to predict CSA-AKI.

Diagnostics, Risk Factors, Treatment and Outcomes of Acute Kidney Injury in a New Paradigm

Acute kidney injury (AKI) is a common clinical condition among patients admitted in the hospitals. The condition is associated with both increased short-term and long-term mortality. With the development of a standardized definition for AKI and the acknowledgment of the impact of AKI on patient outcomes, there has been increased recognition of AKI. Two advances from past decades, the usage of computer decision support and the discovery of AKI biomarkers, have the ability to advance the diagnostic method to and further management of AKI. The increasingly widespread use of electronic health records across hospitals has substantially increased the amount of data available to investigators and has shown promise in advancing AKI research. In addition, progress in the finding and validation of different forms of biomarkers of AKI within diversified clinical environments and has provided information and insight on testing, etiology and further prognosis of AKI, leading to future of precision and personalized approach to AKI management. In this this article, we discussed the changing paradigms in AKI: from mechanisms to diagnostics, risk factors, and management of AKI.

Influence of preoperative serum creatinine level and intraoperative volume of contrast medium on the risk of acute kidney injury after transfemoral transcatheter aortic valve implantation: a retrospective observational study

Objective

This study aimed to determine if contrast medium volume (CMV) is a risk factor for acute kidney injury (AKI) during transcatheter aortic valve implantation (TAVI) via a transfemoral approach performed without major complications. All TAVI procedures performed at our institution between March 2014 and March 2018 were retrospectively reviewed. AKI was diagnosed using the Acute Kidney Injury Network classification based on the Valve Academic Research Consortium-2 definition. Procedures performed via a transapical approach and those in which circulatory dynamics failed intraoperatively were excluded.

Results

Eighty-one (96.4%) of 100 patients scheduled for TAVI were enrolled; seven (8.6%) developed AKI and 74 (91.4%) did not. The serum creatinine (SCr) level was significantly higher (p < 0.05) and the estimated glomerular filtration rate was significantly lower in the AKI group (p < 0.05). The CMV was significantly higher in the AKI group (103 ml vs 84 ml, p < 0.05), as was the CMV × SCr/BW value (3.34 vs 1.49, p < 0.01). The area under the curve for CMV × SCr/BW was 0.9228 and the cut-off value was 2.99. The CMV, SCr, and estimated glomerular filtration rate affect the likelihood of AKI after transfemoral TAVI and a CMV × SCr/BW value > 2.99 accurately predicts AKI.

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4527-2) contains supplementary material, which is available to authorized users.

Packed red blood cell transfusion associates with acute kidney injury after transcatheter aortic valve replacement

Background

Acute kidney injury after cardiac surgery significantly associates with morbidity and mortality. Despite not requiring cardiopulmonary bypass, transcatheter aortic valve replacement patients have an incidence of post-procedural acute kidney injury similar to patients who undergo open surgical aortic valve replacement. Packed red blood cell transfusion has been associated with morbidity and mortality after cardiac surgery. We hypothesized that packed red blood cell transfusion independently associates with acute kidney injury after transcatheter aortic valve replacement, after accounting for other risk factors.

Methods

This is a single-center retrospective cohort study of 116 patients undergoing transcatheter aortic valve replacement. Post-transcatheter aortic valve replacement acute kidney injury was defined by Kidney Disease: Improving Global Outcomes serum creatinine-based criteria. Univariate comparisons between patients with and without post-transcatheter aortic valve replacement acute kidney injury were made for clinical characteristics. Multivariable logistic regression was used to assess independent association of packed red blood cell transfusion with post-transcatheter aortic valve replacement acute kidney injury (adjusting for pre-procedural renal function and other important clinical parameters).

Results

Acute kidney injury occurred in 20 (17.2%) subjects. Total number of packed red blood cells transfused independently associated with post-procedure acute kidney injury (OR = 1.67 per unit, 95% CI 1.13–2.47, P = 0.01) after adjusting for pre-procedure estimated glomerular filtration rate (OR = 0.97 per ml/min/1.73m², 95% CI 0.94–1.00, P = 0.05), nadir hemoglobin (OR = 0.88 per g/dL increase, CI 0.61–1.27, P = 0.50), and post-procedure maximum number of concurrent inotropes and vasopressors (OR = 2.09 per inotrope or vasopressor, 95% CI 1.19–3.67, P = 0.01).

Conclusion

Packed red blood cell transfusion, along with post-procedure use of inotropes and vasopressors, independently associate with acute kidney injury after transcatheter aortic valve replacement. Further studies are needed to elucidate the pathobiology underlying these associations.

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.

Comparison of Outcomes of Transfemoral Versus Transapical Approach for Transcatheter Aortic Valve Implantation

Post hoc analyses of clinical trials have shown superior outcomes for a transfemoral (TF) compared with a transapical (TA) approach for transcatheter aortic valve implantation (TAVI). There are few contemporary data on utilization and outcomes of TF versus TA TAVI in real-world patient populations. Using the National Inpatient Sample 2011 to 2014, we identified TF-TAVI and TA-TAVI procedures using ICD-9 procedure codes 35.05 and 35.06, respectively. A propensity-matched cohort of TF and TA TAVI procedures balanced on 23 baseline characteristics was assembled. Outcomes included in-hospital mortality, acute kidney injury (AKI), AKI requiring dialysis (AKI-D) and postoperative stroke. A total of 7,973 TAVI procedures representative of 39,745 procedures nationally were included in the study. Of these, 80.2% were performed using a TF approach while 19.8% used a TA approach. Patients in the TF-TAVI group were older (mean age 81.7 vs 80.4 years, p < 0.001), with a higher prevalence of heart failure (12.7% vs 7.6%, p < 0.001) and lower prevalence of peripheral vascular disease (28.0% vs 35.5%, p < 0.001) compared with the TA-TAVI group. In 1,576 propensity-matched pairs of TF-TAVI and TA-TAVI procedures, TF-TAVI was associated with significantly lower in-hospital mortality (odds ratio [OR] 0.61, 95% confidence interval [CI] 0.42 to 0.88, p = 0.01), lower rates of AKI (0.53, 95% CI 0.44 to 0.63, p < 0.001), similar rates of AKI-D (OR 0.77, 95% CI 0.44 to 1.38, p = 0.38) and postoperative stroke (OR 1.19, 95% CI 0.67 to 2.10, p = 0.56) compared with TA-TAVI. In conclusion, TF-TAVI is associated with lower rates of in-hospital mortality and AKI compared with TA-TAVI. A TF approach should be preferred over a TA approach for TAVI whenever possible.

U-shape association of serum albumin level and acute kidney injury risk in hospitalized patients

Background

While an association between hypoalbuminemia and increased risk of acute kidney injury (AKI) is well-established, the risk of AKI development and its severity among patients with elevated serum albumin is unclear. The aim of this study was to evaluate the risk of AKI in hospitalized patients stratified by various admission serum albumin levels.

Methods

This single-center retrospective study was conducted at a tertiary referral hospital. All adult hospitalized patients who had admission albumin levels available between January 2009 and December 2013 were enrolled. Admission albumin was categorized based on its distribution into six groups (≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL). The primary outcome was the incidence of hospital-acquired AKI (HAKI). Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission albumin strata using the albumin 3.5 to 3.9 mg/dL (lowest incidence of AKI) as the reference group.

Results

Of the total 9,552 studied patients, HAKI occurred in 1,556 (16.3%) patients. The incidence of HAKI among patients with admission albumin ≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL was 18.3%, 14.3%, 15.5%, 14.2%, 16.7%, and 26.0%, respectively. After adjusting for potential confounders, admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk of HAKI with odds ratios of 1.52 (95% CI 1.18–1.94) and 2.16 (95% CI 1.74–2.69), respectively. While stage 1 HAKI was significantly more frequent among patients with admission albumin ≥4.5 mg/dL (23.0% vs. 11.6%, P<0.001), incidence of stage 3 HAKI was higher in those with albumin ≤2.4 mg/dL (2.8% vs 0.3%, P<0.001).

Conclusion

Admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk for HAKI. Patients with admission albumin ≥4.5 mg/dL had HAKI with a lower intensity when compared with those who had admission albumin levels ≤2.4 mg/dL.

Admission calcium levels and risk of acute kidney injury in hospitalised patients

BACKGROUND

The risk of acute kidney injury (AKI) development among hospitalised patients with elevated calcium levels on admission remains unclear. The aim of this study was to assess the risk of AKI in hospitalised patients stratified by various admission serum calcium levels.

METHODS

This is a single-centre retrospective study conducted at a tertiary referral hospital. All hospitalised adult patients who had admission calcium levels available between 2009 and 2013 were enrolled. Admission calcium was categorised based on its distribution into six groups (≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9, and ≥10.0 mg/dL). The primary outcome was hospital-acquired AKI. Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission calcium strata using calcium levels of 8.0-8.4 mg/dL (lowest incidence of AKI) as the reference group.

RESULTS

A total of 12 784 patients were studied. Hospital-acquired AKI occurred in 1779 (13.9%) patients. The incidence of AKI among patients with admission calcium ≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL was 14.7%, 11.7%, 11.8%, 14.6%, 15.8% and 17.3%, respectively. After adjusting for potential confounders, admission calcium levels ≤7.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL were associated with increased risk of AKI with odds ratios of 1.36 (95%CI 1.08-1.72), 1.29 (95%CI 1.08-1.56), 1.38 (95%CI 1.14-1.68) and 1.51 (95%CI 1.19-1.91), respectively.

CONCLUSION

Admission hypocalcaemia and hypercalcaemia are associated with an increased risk for hospital acquired AKI. Patients with admission hypercalcaemia (≥10 mg/dL) carry a 1.51-fold risk for AKI development during hospitalisation.

In-hospital outcomes comparison of transfemoral vs transapical transcatheter aortic valve replacement in propensity-matched cohorts with severe aortic stenosis

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is the preferred option for high-risk patients with severe aortic stenosis. The preferred access for TAVR is transfemoral (TF). Alternatives include the transapical (TA), trans-subclavian (TS), and direct aortic (TAo) approaches.

HYPOTHESIS

The TF approach is associated with lower in-hospital outcomes as well as shorter length of stay and lower cost of hospitalization.

METHODS

The National Inpatient Sample database from 2012 through 2014 was used to obtain the TAVR study population. International Classification of Diseases, 9th Revision, Clinical Modification procedure codes were utilized to identify the 2 groups. In-hospital outcomes were compared in propensity-score-matched (1:3) cohorts, in which we took TA-TAVR as a control.

RESULTS

A total of 8210 (weighted N = 41 050) patients were identified. Of these, 1622 (weighted N = 8110) patients underwent TA-TAVR and 6588 (weighted N = 32 940) patients underwent TF-TAVR. In-hospital mortality was lower with TF-TAVR (4% vs 5.4%; P = 0.0355), along with a shorter length of stay (7.7 vs 9.7 days; P < 0.0001) and lower median hospitalization cost ($64 216 vs $74 735; P < 0.0001). Secondary outcomes of acute renal failure, transfusion, cardiogenic shock, and composite of all complications were lower with TF-TAVR.

CONCLUSIONS

TF-TAVR is safer and associated with lower in-hospital outcomes compared with TA-TAVR and should be the preferred approach. As TAVR is gaining popularity in intermediate- and low-risk patients, we must not lose sight of the serious mortality and secondary outcomes associated with TA-TAVR access.

Impact of Acute Kidney Injury on Short- and Long-term Outcomes After Transcatheter Aortic Valve Implantation

INTRODUCTION AND OBJECTIVES

Acute kidney injury (AKI) is frequently observed after transcatheter aortic valve implantation (TAVI) and is associated with higher mortality. However, the impact of AKI on long-term outcomes remains controversial. Therefore, we sought to evaluate the impact of AKI on short- and long-term outcomes following TAVI using the Valve Academic Research Consortium 2 criteria.

METHODS

Consecutive patients (n = 794) with severe aortic stenosis who underwent TAVI were included in a multicenter Brazilian registry. Logistic regression analysis was used to identify predictors of AKI. Four-year outcomes were determined as Kaplan-Meier survival curves, and an adjusted landmark analysis was used to test the impact of AKI on mortality among survivors at 12 months.

RESULTS

The incidence of AKI after TAVI was 18%. Independent predictors of AKI were age, diabetes mellitus, major or life-threatening bleeding and valve malpositioning. Acute kidney injury was independently associated with higher risk of all-cause death (adjusted HR, 2.8; 95%CI, 2.0-3.9; P < .001) and cardiovascular mortality (adjusted HR, 2.9; 95%CI, 1.9-4.4; P < .001) over the entire follow-up period. However, when considering only survivors at 12 months, there was no difference in both clinical endpoints (adjusted HR, 1.2; 95%CI, 0.5-2.4; P = .71, and HR, 0.7; 95%CI, 0.2-2.1; P = .57, respectively).

CONCLUSIONS

Acute kidney injury is a frequent complication after TAVI. Older age, diabetes, major or life-threatening bleeding, and valve malpositioning were independent predictors of AKI. Acute kidney injury is associated with worse short- and long-term outcomes. However, the major impact of AKI on mortality is limited to the first year after TAVI.

Persistent acute kidney injury following transcatheter aortic valve replacement

BACKGROUND

Acute kidney injury (AKI) and its severity after transcatheter aortic valve replacement (TAVR) have been associated with worse outcomes. Studies have shown that AKI duration (transient or persistent) affects outcomes independently of AKI severity. This study was undertaken to determine the association, risk factors, and outcomes associated with persistent AKI (pAKI) after TAVR.

METHODS

Adult patients undergoing TAVR at Mayo Clinic between January 1, 2008 and June 30, 2014 were enrolled. pAKI was defined as an increased serum creatinine at hospital discharge (≥0.3 mg/dL or ≥50% from baseline). Risk factors associated with pAKI were identified with multivariate logistic regression.

RESULTS

A total of 386 patients met the inclusion criteria. Fifty patients (13%) had pAKI. Independent risk factors for pAKI on multivariate analysis included diabetes mellitus (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.29-4.66), prior percutaneous coronary intervention (PCI) (OR, 2.39; 95%CI, 1.24-4.80), intra-aortic balloon pump (IABP) use (OR, 8.14; 95%CI, 1.60-45.78), and blood transfusion (OR, 2.22; 95%CI, 1.15-4.27). Protective factors for pAKI included a higher baseline estimated glomerular filtration rate (eGFR) (OR, 0.83 per 10-mL/min/1.73 m² increase in eGFR; 95%CI, 0.71-0.99). After adjusting for the Society of Thoracic Surgeons cardiac surgery risk score, pAKI occurrence remained significantly associated with increased 2-year mortality among hospital survivors (hazard ratio, 2.65; 95%CI, 1.51-4.41).

CONCLUSION

pAKI was significantly associated with higher mortality risk following TAVR. Baseline eGFR, diabetes mellitus, previous PCI, IABP, and blood transfusion were risk factors for post-procedural pAKI.

Association of frailty status with acute kidney injury and mortality after transcatheter aortic valve replacement: A systematic review and meta-analysis

Objective

Frailty is a common condition in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). The aim of this systematic review was to assess the impact of frailty status on acute kidney injury (AKI) and mortality after TAVR.

Methods

A systematic literature search was conducted using MEDLINE, EMBASE, and Cochrane databases from the inception through November 2016. The protocol for this study is registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42016052350). Studies that reported odds ratios, relative risks or hazard ratios comparing the risk of AKI after TAVR in frail vs. non-frail patients were included. Mortality risk was evaluated among the studies that reported AKI-related outcomes. Pooled risk ratios (RR) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

Results

Eight cohort studies with a total of 10,498 patients were identified and included in the meta-analysis. The pooled RR of AKI after TAVR among the frail patients was 1.19 (95% CI 0.97–1.46, I² = 0), compared with non-frail patients. When the meta-analysis was restricted only to studies with standardized AKI diagnosis according to Valve Academic Research Consortium (VARC)-2 criteria, the pooled RRs of AKI in frail patients was 1.16 (95% CI 0.91–1.47, I² = 0). Within the selected studies, frailty status was significantly associated with increased mortality (RR 2.01; 95% CI 1.44–2.80, I² = 58).

Conclusion

The findings from our study suggest no significant association between frailty status and AKI after TAVR. However, frailty status is associated with mortality after TAVR and may aid appropriate patient selection for TAVR.

Transapical versus transfemoral approach and risk of acute kidney injury following transcatheter aortic valve replacement: a propensity-adjusted analysis

BACKGROUND

The aim of this study was to compare the incidence of post-procedural acute kidney injury (AKI) and other renal outcomes in patients undergoing transapical (TA) and transfemoral (TF) approaches for transcatheter aortic valve replacement (TAVR).

METHODS

All consecutive adult patients undergoing TAVR for aortic stenosis from 1 January 2008 to 30 June 2014 at a tertiary referral hospital were included. AKI was defined based on Kidney Disease Improving Global Outcomes (KDIGO) criteria. Logistic regression adjustment, propensity score stratification, and propensity matching were performed to assess the independent association between procedural approach and AKI.

RESULTS

Of 366 included patients, 171 (47%) underwent TAVR via a TA approach. AKI occurrence in this group was significantly higher compared to the TF group (38% vs. 18%, p < .01). The TA approach remained significantly associated with increased risk of AKI after logistic regression (OR 3.20; CI 1.68-4.36) and propensity score adjustment: OR 2.83 (CI 1.66-4.80) for stratification and 3.82 (CI 2.04-7.44) for matching. Nonetheless, there was no statistically significant difference among the TA and TF groups with respect to major adverse kidney events (MAKE) or estimated glomerular filtration rate (eGFR) at six months post-procedure.

CONCLUSION

In a cohort of patients undergoing TAVR for aortic stenosis, a TA approach significantly increases the AKI risk compared with a TF approach. However, the TAVR approach did not affect severe renal outcomes or long-term renal function.