Associations of anemia and renal dysfunction with outcomes among patients hospitalized for acute decompensated heart failure with preserved or reduced ejection fraction

Clinical phenotypes according to diuretic combination in acute heart failure

BACKGROUND

The treatment of congestion in heart failure (HF) is a challenge despite the therapeutic arsenal available. The aim of this study was to analyze different combinations of diuretics used to resolve congestion in patients admitted for decompensated HF and to define clinical profiles according to these treatments.

METHODS

Single-center study of 1,559 patients admitted for decompensated HF was done between 2016 and 2020. Patients were grouped according to the diuretic combination that led to clinical stabilization and discharge from the hospital: (1) Loop diuretic. (2) Loop diuretic + distal tubule (antialdosterone ± thiazides). (3) Loop diuretic + distal + proximal tubule (acetazolamide ± SGLT2 inhibitor). (4) Loop diuretic + distal tubule + collecting duct (tolvaptan). (5) Loop diuretic + distal + proximal + collecting duct. Based on these diuretic combinations, profiles with clinical, analytical, and echocardiographic differences were established.

RESULTS

There were more previous hospitalizations in groups 4 and 5 (p = 0.001) with a predominance of pulmonary congestion in profiles 1 and 2 and systemic congestion in 3, 4, and 5. Creatinine and CA125 were higher in profiles 4 and 5 (p = 0.01 and p = 0.0001), with no differences in NT-proBNP. Profiles 4 and 5 had a higher proportion of dilatation and depression of right ventricular (p = 0.0001) and left ventricular (p = 0.003) function. Diuretic therapy-defined groups showed difference in clinical characteristics.

CONCLUSIONS

The diuretic treatment used identifies five clinical profiles according to the degree of congestion, renal function, CA125, and right ventricular functionality. These profiles would guide the best diuretic treatment on admission.

Prediction models for major adverse cardiovascular events following ST-segment elevation myocardial infarction and subgroup-specific performance

Background

ST-segment elevation myocardial infarction (STEMI) patients are at a high residual risk of major adverse cardiovascular events (MACEs) after revascularization. Risk factors modify prognostic risk in distinct ways in different STEMI subpopulations. We developed a MACEs prediction model in patients with STEMI and examined its performance across subgroups.

Methods

Machine-learning models based on 63 clinical features were trained in patients with STEMI who underwent PCI. The best-performing model (the iPROMPT score) was further validated in an external cohort. Its predictive value and variable contribution were studied in the entire population and subgroups.

Results

Over 2.56 and 2.84 years, 5.0% and 8.33% of patients experienced MACEs in the derivation and external validation cohorts, respectively. The iPROMPT score predictors were ST-segment deviation, brain natriuretic peptide (BNP), low-density lipoprotein cholesterol (LDL-C), estimated glomerular filtration rate (eGFR), age, hemoglobin, and white blood cell (WBC) count. The iPROMPT score improved the predictive value of the existing risk score, with an increase in the area under the curve to 0.837 [95% confidence interval (CI): 0.784-0.889] in the derivation cohort and 0.730 (95% CI: 0.293-1.162) in the external validation cohort. Comparable performance was observed between subgroups. The ST-segment deviation was the most important predictor, followed by LDL-C in hypertensive patients, BNP in males, WBC count in females with diabetes mellitus, and eGFR in patients without diabetes mellitus. Hemoglobin was the top predictor in non-hypertensive patients.

Conclusion

The iPROMPT score predicts long-term MACEs following STEMI and provides insights into the pathophysiological mechanisms for subgroup differences.

Impact of weight loss in patients with heart failure with preserved ejection fraction: results from the FLAGSHIP study

Aims

Weight loss (WL) is a poor prognostic factor for patients with heart failure (HF) with reduced ejection fraction. However, its prognostic impact on patients with HF with preserved ejection fraction (HFpEF) remains unestablished. The evidence regarding the effects of obesity on the prognosis of WL is also unclear. We aimed to identify the risk factors for WL and examine the association between WL and prognosis of HFpEF in obese and non‐obese patients.

Methods and results

In this multicentre cohort study, the data of 573 patients hospitalized with HFpEF [median age: 78 years (interquartile range, 71–84 years); 49.2% female] were identified from hospital databases. WL was defined as ≥5% weight reduction within 6 months after discharge. Obesity was defined according to Japanese criteria as body mass index ≥25 kg/m². The main study outcomes were all‐cause mortality and HF rehospitalization between 6 and 24 months after hospital discharge. Logistic regression analysis and Cox proportional hazards regression analysis were performed to identify independent the risk factors associated with WL and to calculate the hazard ratios (HRs) associated with adverse outcomes. The prevalence of obesity at discharge was 21.1%. At 6 month follow‐up, WL occurred in 17.4% and 10.8% of the obese and non‐obese patients, respectively. Onset of WL in non‐obese patients was associated with prior hospitalization for HF [odds ratio (OR) 2.39, 95% confidence interval (CI) 1.22–4.68, P = 0.011] and high levels of brain natriuretic peptide (OR 2.32, CI 1.17–4.60, P = 0.015). In obese patients, WL was associated with the use of mineralocorticoid receptor antagonists (OR 3.26, CI 1.08–9.76, P = 0.03) and vasopressin receptor antagonists (OR 6.61, CI 2.03–21.2, P = 0.001). During 1021.3 person‐years of follow‐up, 31 patients died, and upon 1081.0 person‐years follow‐up, 84 patients required rehospitalization for HF. In proportional hazards analysis, WL was associated with all‐cause mortality (HR 5.12, CI 2.08–12.5, P < 0.001) and HF rehospitalization (HR 2.63, CI 1.38–5.01, P = 0.003) after adjustment for confounders in non‐obese patients, but not in obese patients.

Conclusions

Weight loss should be considered as an indicator for monitoring worsening of HF condition in non‐obese patients with HFpEF. WL was not associated with adverse events in obese patients with HFpEF, possibly due to appropriate fluid management during follow‐up.

Cardionephrology from the point of view of the cardiologist: no more agree to disagree-getting to 'yes' for every patient

Whether one wants to or not, interactions between the heart and the kidneys exist and manifest nevertheless. Both from theoretical and clinical perspectives, it seems the need for a subspecialty of cardionephrology seems justified. Our editorial is a cardiologist perspective on the article by Diez and Ortiz published in Clinical Kidney Journal related to the 'need for a cardionephrology subspecialty'. We analysed the historical similarities of the emergence of already ingrained clinical fields with the current needs in the cardionephrology sector. We motivated our approach based on novel cardiovascular diagnostic and therapeutic developments and significant pathophysiological differences from a cardiological perspective, accounting for the foundation of a novel sustainable medical field. One of the sensitive issues we also addressed was the operationality and applicability of the principles. We answered with some examples from high-risk debatable contexts the question of where a cardionephrologist should be integrated. Clarifying the operationality aspects would be a positive shift towards improving guidelines adherence in managing complex patients. In conclusion, we underline that the necessity of a cardionephrologist must be addressed from an operational and scientific perspective, with the ultimate goal of reducing mortality and complications in cardiorenal patients.

Renal dysfunction in cardiovascular diseases and its consequences

It is well known that the heart and kidney and their synergy is essential for hemodynamic homeostasis. Since the early XIX century it has been recognized that cardiovascular and renal diseases frequently coexist. In the nephrological field, while it is well accepted that renal diseases favor the occurrence of cardiovascular diseases, it is not always realized that cardiovascular diseases induce or aggravate renal dysfunctions, in this way further deteriorating cardiac function and creating a vicious circle. In the same clinical field, the role of venous congestion in the pathogenesis of renal dysfunction is at times overlooked. This review carefully quantifies the prevalence of chronic and acute kidney abnormalities in cardiovascular diseases, mainly heart failure, regardless of ejection fraction, and the consequences of renal abnormalities on both organs, making cardiovascular diseases a major risk factor for kidney diseases. In addition, with regard to pathophysiological aspects, we attempt to substantiate the major role of fluid overload and venous congestion, including renal venous hypertension, in the pathogenesis of acute and chronic renal dysfunction occurring in heart failure. Furthermore, we describe therapeutic principles to counteract the major pathophysiological abnormalities in heart failure complicated by renal dysfunction. Finally, we underline that the mild transient worsening of renal function after decongestive therapy is not usually associated with adverse prognosis. Accordingly, the coexistence of cardiovascular and renal diseases inevitably means mediating between preserving renal function and improving cardiac activity to reach a better outcome.

The CRAS-EAHFE study: Characteristics and prognosis of acute heart failure episodes with cardiorenal-anaemia syndrome at the emergency department

BACKGROUND

The coexistence of other comorbidities confers poor outcomes in patients with acute heart failure. Our aim was to determine the characteristics of patients with acute heart failure and cardiorenal anaemia syndrome and the relationship between renal dysfunction and anaemia, alone or combined as cardiorenal anaemia syndrome, on short-term outcomes.

METHODS

We analysed the Epidemiology of Acute Heart Failure in Emergency Departments registry (cohort of patients with acute heart failure in Spanish emergency departments). Renal dysfunction was defined by an estimated glomerular filtration rate <60 ml/min/m², anaemia by haemoglobin values <12/<13 g/dl in women/men, and cardiorenal anaemia syndrome as the presence of both. Comparisons were made according to cardiorenal-anaemia syndrome positive (CRAS+) with respect to the rest of patients (CRAS-) and according the presence of renal dysfunction (RD+) and anaemia (A+), (alone, RD+/A-, RD-/A+) or in combination (RD+/A+; i.e. CRAS+) with respect to patients without renal dysfunction and anaemia (RD-/A-). The primary outcome was 30-day mortality, and the secondary outcomes were need for admission, prolonged hospitalisation (>10 days), in-hospital mortality during the index event, and reconsultation and the combination of 30-day post-discharge reconsultation/death. These short-term outcomes were compared and adjusted for differences among groups.

RESULTS

Of the 13,307 patients analysed, CRAS+ (36.4%) was associated with older age, multiple comorbidities, chronic use of loop diuretics, oedemas and hypotension. The 30-day mortality in CRAS+ was greater than in CRAS- (hazard ratio = 1.46, 95% confidence interval = 1.26-1.68) and RD-/A- (hazard ratio = 1.83, 95% confidence interval = 1.46-2.28) control groups. The mortality level was also higher in RD+/A- (hazard ratio = 1.40, 95% confidence interval = 1.10-1.78) and higher, but not statistically significant, in RD-/A+ (hazard ratio = 1.28, 95% confidence interval = 0.99-1.63) with respect to RD-/A-. All of the secondary outcomes, when related to CRAS- and RD-/A- control groups, were worse for CRAS+ and to a lesser extent, RD+/A-, being more rarely observed in RD-/A+.

CONCLUSIONS

Cardiorenal anaemia syndrome in acute heart failure is related to greater mortality and worse short-term outcomes, and the impact of renal dysfunction and anaemia seems to be additive.

Hemoglobin concentration and the risk of hemorrhagic and ischemic stroke in patients undergoing hemodialysis: the Q-cohort study

Background

The contribution of the hemoglobin concentration to the incidence of hemorrhagic or ischemic stroke in patients undergoing hemodialysis is unclear.

Methods

In total, 3436 patients undergoing prevalent hemodialysis were followed up for 4 years. The primary outcome was the first development of hemorrhagic or ischemic stroke. The baseline hemoglobin concentration was divided into quartiles [hemoglobin (g/dL): Q1, ≤9.7; Q2, 9.8-10.5; Q3, 10.6-11.1; Q4, ≥11.2]. The association between the hemoglobin concentration and each type of stroke was examined using the Kaplan-Meier method and a Cox proportional hazards model.

Results

During the follow-up period, 76 (2.2%) patients developed hemorrhagic stroke and 139 (4.0%) developed ischemic stroke. The 4-year incidence rate of hemorrhagic stroke was significantly higher in patients with lower hemoglobin concentrations. Compared with the quartile of patients with the highest hemoglobin concentrations (Q4), the multivariable-adjusted hazard ratios for hemorrhagic stroke were 1.18 (95% confidence interval, 0.56-2.51), 1.59 (0.82-3.21) and 2.31 (1.16-4.73) in patients in Q3, Q2 and Q1, respectively. No association was identified between the 4-year incidence rate of ischemic stroke and the hemoglobin concentration. Compared with the quartile of patients with the lowest hemoglobin concentrations (Q1), the multivariable-adjusted hazard ratios for ischemic stroke were 1.17 (95% confidence interval, 0.73-1.89), 0.88 (0.51-1.51) and 1.10 (0.66-1.83) in patients in Q2, Q3 and Q4, respectively.

Conclusions

Our results suggest that low hemoglobin concentrations are associated with a high risk of hemorrhagic stroke, but not of ischemic stroke, in patients undergoing hemodialysis.

Preeclampsia: a gestational cardiorenal syndrome

It is generally accepted today that there are two different types of preeclampsia: an early-onset or placental type and a late-onset or maternal type. In the latent phase, the first one presents with a low output/high resistance circulation eventually leading in the late second or early third trimester to an intense and acutely aggravating systemic disorder with an important impact on maternal and neonatal mortality and morbidity; the other type presents initially as a high volume/low resistance circulation, gradually evolving to a state of circulatory decompensation usually in the later stages of pregnancy, with a less severe impact on maternal and neonatal outcome. For both processes, numerous dysfunctions of the heart, kidneys, arteries, veins and interconnecting systems are reported, most of them presenting earlier and more severely in early- than in late-onset preeclampsia; however, some very specific dysfunctions exist for either type. Experimental, clinical and epidemiological observations before, during and after pregnancy are consistent with gestation-induced worsening of subclinical pre-existing chronic cardiovascular dysfunction in early-onset preeclampsia, and thus sharing the pathophysiology of cardiorenal syndrome type II, and with acute volume overload decompensation of the maternal circulation in late-onset preeclampsia, thus sharing the pathophysiology of cardiorenal syndrome type 1. Cardiorenal syndrome type V is consistent with the process of preeclampsia superimposed upon clinical cardiovascular and/or renal disease, alone or as part of a systemic disorder. This review focuses on the specific differences in haemodynamic dysfunctions between the two types of preeclampsia, with special emphasis on the interorgan interactions between heart and kidneys, introducing the theoretical concept that the pathophysiological processes of preeclampsia can be regarded as the gestational manifestations of cardiorenal syndromes.

C-reactive protein level on admission and time to and cause of death in patients hospitalized for acute heart failure

Aims

We analysed the association between C-reactive protein (CRP) levels measured on admission and timing and cause of death among patients hospitalized for acute heart failure (AHF).

Methods and Results

The ATTEND study prospectively registered 4777 hospitalized AHF patients with data on CRP levels on admission. Mortality risks were assessed by univariable and multivariable Cox proportional and non-proportional hazards models. The overall median CRP level was 5.8 mg/L (intertertile range: 2.9-11.8 mg/L). There were significant increases in all-cause, cardiac, and non-cardiac mortalities from the lowest to highest CRP tertiles throughout the follow-up periods. Within 120 days after admission, CRP levels in the highest tertile (>11.8 mg/L) were independently associated with higher all-cause (hazard ratio [HR], 2.21; 95% confidence interval [CI], 1.69-2.88; P < 0.001), cardiac (HR, 1.88; 95% CI, 1.37-2.58; P < 0.001), and non-cardiac (HR, 3.21; 95% CI, 1.94-5.32; P < 0.001) deaths, while levels in the second tertile (2.9-11.8 mg/L) were not associated with poorer survival, compared with levels in the first tertile (<2.9 mg/L). However, in terms of cardiac death, the hazard ratios for patients in the third tertile decreased markedly with time and only CRP levels in second tertile were independently associated with poorer cardiac survival after the follow-up period of 120 days (HR, 1.44; 95% CI, 1.09-1.89; P = 0.011).

Conclusions

Markedly elevated CRP levels at admission in patients with AHF may be associated with higher short-term cardiac and non-cardiac mortalities. In addition, modestly elevated CRP levels may be associated with higher mortality, especially cardiac mortality, after 120 days of long-term follow-up.

Incidence and impact of cardiorenal anaemia syndrome on all-cause mortality in acute heart failure patients stratified by left ventricular ejection fraction in the Middle East

AIMS

This study aims to evaluate the incidence and impact of cardiorenal anaemia syndrome (CRAS) on all-cause mortality in acute heart failure (AHF) patients stratified by left ventricular ejection fraction (LVEF) status in the Middle East.

METHODS AND RESULTS

Data were analysed from 4934 consecutive patients admitted to 47 hospitals in seven Middle Eastern countries (Saudi Arabia, Oman, Yemen, Kuwait, United Arab Emirates, Qatar, and Bahrain) with AHF from February to November 2012. CRAS was defined as AHF with estimated glomerular filtration rate of <60 mL/min and low haemoglobin (<13 g/dL for men or <12 g/dL for women). Analyses were performed using univariate and multivariate statistical techniques. The overall mean age of the cohort was 59 ± 15 years, 62% (n = 3081) were men, and 27% (n = 1319) had CRAS. Co-morbid conditions were common including hypertension (n = 3014; 61%), coronary artery disease (n = 2971; 60%), and diabetes mellitus (n = 2449; 50%). A total of 79% (n = 3576) of the patients had AHF with reduced ejection fraction (HFrEF) (LVEF < 50%). CRAS patients were associated with major bleeding (1.29% vs. 0.6%; P = 0.017), blood transfusion (10.1% vs. 3.0%; P < 0.001), higher re-admission rate for AHF at 3 months' follow-up (27.6% vs. 18.8%; P < 0.001) and at 12 months' follow-up (34.3% vs. 26.2%; P < 0.001). Multivariate logistic regression demonstrated that patients with CRAS were associated with higher odds of all-cause mortality during hospital admission [adjusted odds ratio (aOR), 2.10; 95% confidence interval (CI): 1.34-3.31; P = 0.001], at 3 months' follow-up (aOR, 1.48; 95% CI: 1.07-2.06; P = 0.018), and at 12 months' follow-up (aOR, 1.45; 95% CI: 1.12-1.87; P = 0.004). Stratified analyses showed that CRAS patients with HFrEF were associated with higher odds of all-cause mortality during hospital admission (aOR, 2.03; 95% CI: 1.20-3.45; P = 0.009) and at 12 months' follow-up (aOR, 1.42; 95% CI: 1.06-1.89; P = 0.019) but not at 3 months' follow-up (aOR, 1.43; 95% CI: 0.98-2.09; P = 0.063). However, in AHF patients with preserved ejection fraction (LVEF ≥ 50%), CRAS was not associated with higher odds of all-cause mortality not only during hospital admission (aOR, 2.15; 95% CI: 0.84-5.55; P = 0.113) but also at 3 months' follow-up (aOR, 1.87; 95% CI: 0.93-3.76; P = 0.078) and at 12 months' follow-up (aOR, 1.59; 95% CI: 0.91-2.76; P = 0.101).

CONCLUSIONS

The incidence of CRAS was 27%. CRAS was associated with higher odds of all-cause mortality in AHF patients in the Middle East, especially in those with HFrEF.

Renal function and anemia in relation to short- and long-term prognosis of patients with acute heart failure in the period 1985-2008: A clinical cohort study

BACKGROUND

Renal dysfunction and anaemia are common in patients with acute heart failure (HF). It is not known whether their combined presence has additive prognostic value. We investigated their prognostic value separately and in combination, on prognosis in acute HF patients. Furthermore, we examined whether the improvement in prognosis was comparable between patients with and without renal dysfunction.

METHODS AND RESULTS

This prospective registry includes 1783 patients admitted to the (Intensive) Coronary Care Unit for acute HF in the period of 1985-2008. The outcome measure was the composite of all-cause mortality, heart transplantation and left ventricular assist device implantation. In patients without renal dysfunction, anemia was associated with worse 30-day outcome (HR 2.91; [95% CI 1.69-5.00]), but not with 10-year outcome (HR 1.13 [95% CI 0.93-1.37]). On the contrary, anemia was found to influence prognosis in patients with renal dysfunction, both at 30 days (HR 1.93 [95% CI 1.33-2.80]) and at 10 years (HR 1.27 [95% CI 1.10-1.47]). Over time, the 10-year survival rate improved in patients with preserved renal function (HR 0.73 [95% CI 0.55-0.97]), but not in patients with renal dysfunction.

CONCLUSION

The long-term prognosis of acute HF patients with a preserved renal function was found to have improved significantly. However, the prognosis of patients with renal dysfunction did not change. Anemia was a strong prognosticator for short-term outcome in all patients. In patients with renal dysfunction, anemia was also associated with impaired long-term prognosis.

Association of admission and discharge anemia status with outcomes in patients hospitalized for acute decompensated heart failure: Differences between patients with preserved and reduced ejection fraction

Background:

In acute decompensated heart failure patients with a preserved or reduced ejection fraction, the association of admission and discharge anemia status with outcomes remains unclear.

Methods and results:

Of the 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 4433 patients (2017 with a preserved and 2416 with a reduced ejection fraction) were examined to investigate associations among the anemia status at admission and discharge (no anemia, developed anemia, resolved anemia, or persistent anemia), a preserved or reduced ejection fraction and the primary endpoint (all-cause death and readmission for heart failure). In the preserved ejection fraction group, adjusted analysis showed that either developed or persistent anemia was associated with a significantly higher risk of the primary endpoint relative to no anemia (hazard ratio: 1.53; 95% confidence interval (CI): 1.11–2.11; p=0.009 and hazard ratio: 1.60; 95% CI: 1.26–2.04; p<0.001, respectively), but there was no association between resolved anemia and the primary endpoint (hazard ratio: 0.98; 95% CI: 0.67–1.45; p=0.937). In the reduced ejection fraction group, either developed or resolved anemia was associated with a tendency toward higher risk of the primary endpoint relative to no anemia (hazard ratio: 1.29; 95% CI: 0.95–1.62; p=0.089, and hazard ratio: 1.31; 95% CI: 0.96–1.77; p=0.085, respectively), while persistent anemia was associated with a significantly higher risk of the primary endpoint relative to no anemia (hazard ratio: 1.36; 95% CI: 1.12–1.65; p=0.002).

Conclusions:

In acute decompensated heart failure patients, the association of admission and discharge anemia status with outcomes differs markedly between patients with a preserved or reduced ejection fraction.

Prognostic Value of Chronic Kidney Disease Measures in Patients With Cardiac Disease

Chronic kidney disease (CKD) is considered a global public health issue. The latest international clinical guideline emphasizes characterization of CKD with both glomerular filtration rate (GFR) and albuminuria. CKD is closely related to cardiac disease and increases the risk of adverse outcomes among patients with cardiovascular disease (CVD). Indeed, numerous studies have investigated the association of CKD measures with prognosis among patients with CVD, but most of them have focused on kidney function, with limited data on albuminuria. Consequently, although there are several risk prediction tools for patients with CVD incorporating kidney function, to our knowledge, none of them include albuminuria. Moreover, the selection of the kidney function measure (e.g., serum creatinine, creatinine-based estimated GFR, or blood urea nitrogen) in these tools is heterogeneous. In this review, we will summarize these aspects, as well as the burden of CKD in patients with CVD, in the current literature. We will also discuss potential mechanisms linking CKD to secondary events and consider future research directions. Given their clinical and public health importance, for CVD we will focus on 2 representative cardiac diseases: myocardial infarction and heart failure.

Association of anemia and renal dysfunction with in-hospital mortality among patients hospitalized for acute heart failure syndromes with preserved or reduced ejection fraction

BACKGROUND

The aim of this study was to evaluate the association of anemia and renal dysfunction with in-hospital outcomes in acute heart failure syndromes patients with preserved or reduced ejection fraction.

METHODS AND RESULTS

Of the 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 4693 patients were evaluated to investigate the association among anemia, renal dysfunction, a preserved or reduced ejection fraction and in-hospital mortality. They were divided into four groups based on hemoglobin and estimated glomerular filtration rate at admission. The in-hospital mortality rate was 5.9% and 6.9% of the preserved and reduced ejection fraction groups, respectively. After adjustment for multiple comorbidities, there was no association of either anemia or renal dysfunction alone with in-hospital mortality in preserved ejection fraction patients, but the combination of anemia and renal dysfunction was associated with a somewhat higher risk of in-hospital mortality than that without either condition (odds ratio (OR), 2.75; 95% confidence interval (CI), 0.72-10.41; p=0.137). In reduced ejection fraction patients, adjusted analysis showed that a significantly higher risk of in-hospital mortality was associated with anemia alone (OR, 2.56; 95% CI, 1.10 -5.94; p=0.029) and with anemia plus renal dysfunction (OR, 2.34; 95% CI, 1.09-5.03; p=0.029) relative to the risk without either condition.

CONCLUSIONS

Our findings demonstrate that anemia combined with renal dysfunction is not a risk factor for in-hospital mortality in patients with a preserved ejection fraction, whereas anemia is an independent predictor of in-hospital mortality risk in reduced ejection fraction patients regardless of renal dysfunction.

Long-term remote organ consequences following acute kidney injury

Acute kidney injury (AKI) has been a global health epidemic problem with soaring incidence, increased long-term risks for multiple comorbidities and mortality, as well as elevated medical costs. Despite the improvement of patient outcomes following the advancements in preventive and therapeutic strategies, the mortality rates among critically ill patients with AKI remain as high as 40–60 %. The distant organ injury, a direct consequence of deleterious systemic effects, following AKI is an important explanation for this phenomenon. To date, most evidence of remote organ injury in AKI is obtained from animal models. Whereas the observations in humans are from a limited number of participants in a relatively short follow-up period, or just focusing on the cytokine levels rather than clinical solid outcomes. The remote organ injury is caused with four underlying mechanisms: (1) “classical” pattern of acute uremic state; (2) inflammatory nature of the injured kidneys; (3) modulating effect of AKI of the underlying disease process; and (4) healthcare dilemma. While cytokines/chemokines, leukocyte extravasation, oxidative stress, and certain channel dysregulation are the pathways involving in the remote organ damage. In the current review, we summarized the data from experimental studies to clinical outcome studies in the field of organ crosstalk following AKI. Further, the long-term consequences of distant organ-system, including liver, heart, brain, lung, gut, bone, immune system, and malignancy following AKI with temporary dialysis were reviewed and discussed.