Cardio-renal syndromes: report from the consensus conference of the acute dialysis quality initiative

Clinical values of serum NGAL combined with NT-proBNP in the early prognosis of type 1 cardiorenal syndrome

BACKGROUND

Cardiorenal syndrome (CRS) is a condition that defines disorders of the heart and kidneys whereby "acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other". Early diagnosis of its biomarkers has a significant impact on the treatment and prognosis of the CRS. Elevated serum NGAL and NT-proBNP levels are independent risk factors for predicting heart and kidney disease. Therefore, we proposed early detection of type 1 CRS using serum NGAL in combination with NT-proBNP.

OBJECTIVE

This study intended to investigate the clinical value of serum NGAL in combination with NT-proBNP in the early diagnosis of type 1 CRS.

METHODS

In this paper, 80 patients with type 1 CRS and 80 healthy controls admitted to our hospital from January 2019 to August 2020 were retrospectively included, and the predictive value of single index and combined indices for predicting CRS were judged by calculating the correlation between serum NGAL, NT-proBNP and the creatinine levels and plotting receiver operating characteristic (ROC) curves.

RESULTS

There was no difference in baseline data between the control and patient groups. Serum NGAL and NT-proBNP in the patient group were significantly higher than those in the control group, and were positively correlated with changes in blood creatinine. The ROC curves showed that serum NGAL and NT-proBNP independently had a high predictive value for CRS, and the combination of the two had a better predictive value.

CONCLUSION

Serum NGAL in combination with NT-proBNP is of high clinical value for the early diagnosis of type 1 CRS.

Cardiovascular and Renal Disease in Chronic Critical Illness

With advances in critical care, patients who would have succumbed in previous eras now survive through hospital discharge. Many survivors suffer from chronic organ dysfunction and induced frailty, representing an emerging chronic critical illness (CCI) phenotype. Persistent and worsening cardiovascular and renal disease are primary drivers of the CCI phenotype and have pathophysiologic synergy, potentiating one another and generating a downward spiral of worsening disease and clinical outcomes manifest as cardio-renal syndromes. In addition to pharmacologic therapies (e.g., diuretics, beta adrenergic receptor blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and blood pressure control), special consideration should be given to behavioral modifications that avoid the pitfalls of polypharmacy and suboptimal renal and hepatic dosing, to which CCI patients may be particularly vulnerable. Smoking cessation, dietary modifications (e.g., early high-protein nutrition and late low-sodium diets), and increased physical activity are advised. Select patients benefit from cardiac re-synchronization therapy or renal replacement therapy. Coordinated, patient-centered care bundles may improve compliance with standards of care and patient outcomes. Given the complex, heterogeneous nature of cardiovascular and renal disease in CCI and the dismal long-term outcomes, further research is needed to clarify pathophysiologic mechanisms of cardio-renal syndromes in CCI and develop targeted therapies.

Myocardial Iron Deficiency Quantification and Effective Cardiac Iron Management Strategy Exploration evaluated by Cardiac T2* Mapping in End-Stage Renal Disease Patients

PURPOSE

To explore myocardial iron content using Cardiac T2* Mapping in dialysis patients undergoing oral iron therapy or intravenous iron supplements compared to healthy controls.

METHODS

Fifty-nine dialysis patients, including 30 peritoneal dialysis (PD) patients who underwent oral iron therapy, 29 hemodialysis (HD) dialysis patients who underwent intravenous iron supplements, and 30 healthy controls were included in the study. Cardiac MRI, including cine, T2 stir, and T2* mapping, was conducted at 3.0T. Quantitive T2* mapping, Cine imaging analysis was performed by two radiologists using cvi42.

RESULTS

The global cardiac T2* value was higher in dialysis patients than in healthy controls (27.1 ± 6.29 ms versus 24.6 ± 3.60 ms, p< 0.05). The global cardiac T2* value of PD patients was higher than that of HD patients (28.5 ± 4.30 ms versus 25.x7 ± 3.54 ms, p< 0.05). The anteroseptal cardiac T2* value was higher in PD patients than in healthy controls (32.0 ± 4.49 ms versus 27.8 ± 4.02 ms, p< 0.05). The global T2* value negatively correlated with left ventricular ejection fraction (LVEF), peak radial strain, circumferential strain, and longitudinal strain.

CONCLUSION

Our study confirmed that PD patients have myocardial iron deficiency despite undergoing oral iron therapy compared to HD patients who received intravenous iron treatments. And the Cardiac T2* value was found to be an independent risk factor and predictor of LVEF and left ventricular altered mechanics. Intravenous iron supplements may be an effective cardiac iron management strategy in patients with HD-dependent end-stage renal disease.

End-stage kidney disease in patients with clinically manifest vascular disease; incidence and risk factors: results from the UCC-SMART cohort study

BACKGROUND

Patients with cardiovascular disease (CVD) are at increased risk of end-stage kidney disease (ESKD). Insights into the incidence and role of modifiable risk factors for end-stage kidney disease may provide means for prevention in patients with cardiovascular disease.

METHODS

We included 8402 patients with stable cardiovascular disease. Incidence rates (IRs) for end-stage kidney disease were determined stratified according to vascular disease location. Cox proportional hazard models were used to assess the risk of end-stage kidney disease for the different determinants.

RESULTS

Sixty-five events were observed with a median follow-up of 8.6 years. The overall incidence rate of end-stage kidney disease was 0.9/1000 person-years. Patients with polyvascular disease had the highest incidence rate (1.8/1000 person-years). Smoking (Hazard ratio (HR) 1.87; 95% CI 1.10-3.19), type 2 diabetes (HR 1.81; 95% CI 1.05-3.14), higher systolic blood pressure (HR 1.37; 95% CI 1.24-1.52/10 mmHg), lower estimated glomerular filtration rate (eGFR) (HR 2.86; 95% CI 2.44-3.23/10 mL/min/1.73 m²) and higher urine albumin/creatinine ratio (uACR) (HR 1.19; 95% CI 1.15-1.23/10 mg/mmol) were independently associated with elevated risk of end-stage kidney disease. Body mass index (BMI), waist circumference, non-HDL-cholesterol and exercise were not independently associated with risk of end-stage kidney disease.

CONCLUSIONS

Incidence of end-stage kidney disease in patients with cardiovascular disease varies according to vascular disease location. Several modifiable risk factors for end-stage kidney disease were identified in patients with cardiovascular disease. These findings highlight the potential of risk factor management in patients with manifest cardiovascular disease.

Quality and quantity culture effectively restores functional and proliferative capacities of endothelial progenitor cell in end-stage renal disease patients

BACKGROUND

Endothelial cell dysfunction plays the crucial role in initiation and propagation of obstructive arteriosclerosis which ultimately causes arterial obstructive syndrome. Additionally, severe endothelial progenitor cells (EPC) dysfunction is always found in those of end-stage renal disease (ESRD) patients. This study tested the hypothesis that a novel method, named "quality and quantity (QQ) culture", could successfully improve the EPC proliferation and function in ESRD patients.

MATERIALS AND METHODS

Peripheral blood mononuclear cells (PBMNCs) were isolated from age-matched control subjects (i.e., normal renal function) (group 1) and ESRD patients (group 2), followed by culture in either conventional EPC culture for one month or in QQ culture for 7 days, respectively. The result showed that as compared to the conventional EPC culture method, the EPC population and M2-like population/ratio (M2/M1) were significantly enriched in QQ culture both in groups 1 and 2 (all p < 0.001), but these parameters did not differ between the groups. As compared with conventional EPC culture, the angiogenesis capacity and colony formation were significantly increased in QQ culture (all p < 0.001), but they showed no difference between groups 1 and 2. In RAW264.7 macrophages treated by liposaccharide, the gene expressions and ELISA findings of pro-inflammatory cytokines (IL-1β/IL-6/TGF-β) and inflammatory mediator (iNOS) were significantly reduced in QQ culture than in conventional EPC culture in groups 1 and 2 (all p < 0.001), but they showed no difference between the groups.

CONCLUSIONS

This study demonstrated that QQ culture enhanced number, proliferation, and angiogenesis of EPCs and anti-inflammatory capacity in ESRD patients.

Vascular pathologies in chronic kidney disease: pathophysiological mechanisms and novel therapeutic approaches

Cardiovascular disease (CVD) is a major cause of death in patients with chronic kidney disease (CKD). Both conditions are rising in incidence as well as prevalence, creating poor outcomes for patients and high healthcare costs. Recent data suggests CKD to be an independent risk factor for CVD. Accumulation of uremic toxins, chronic inflammation, and oxidative stress have been identified to act as CKD-specific alterations that increase cardiovascular risk. The association between CKD and cardiovascular mortality is markedly influenced through vascular alterations, in particular atherosclerosis and vascular calcification (VC). While numerous risk factors promote atherosclerosis by inducing endothelial dysfunction and its progress to vascular structural damage, CKD affects the medial layer of blood vessels primarily through VC. Ongoing research has identified VC to be a multifactorial, cell-mediated process in which numerous abnormalities like mineral dysregulation and especially hyperphosphatemia induce a phenotype switch of vascular smooth muscle cells to osteoblast-like cells. A combination of pro-calcifying stimuli and an impairment of inhibiting mechanisms like fetuin A and vitamin K-dependent proteins like matrix Gla protein and Gla-rich protein leads to mineralization of the extracellular matrix. In view of recent studies, intercellular communication pathways via extracellular vesicles and microRNAs represent key mechanisms in VC and thereby a promising field to a deeper understanding of the involved pathomechanisms. In this review, we provide an overview about pathophysiological mechanisms connecting CKD and CVD. Special emphasis is laid on vascular alterations and more recently discovered molecular pathways which present possible new therapeutic targets.

Body composition and ventricular function in hemodialysis patients

There is no evidence about the potential role of body composition on cardiovascular mortality in dialysis patients. The aim of this study was to assess the relationship between body composition and changes in ventricular function. We conducted an observational study over a population of 78 patients on chronic hemodialysis. A transthoracic echocardiogram and a bioimpedance were performed at the beginning and at the end of the study. The mean follow-up time was 30.6 months. Patients who had a higher fat tissue index (FTI > 9.20 kg/m² ) experienced a worsening in right and left ventricular function. They developed a greater fall in tricuspid annular plane systolic excursion (TAPSE) (-1 ± 4.3 mm) and left ventricular ejection fraction (LVEF)(-4.2 ± 6.8%), compared to those with lower FTI (p = 0.032 and p = 0.045, respectively). No associations were found between any other echocardiography or body composition parameters and overall mortality. Patients with right ventricular dysfunction (determined as TAPSE) experienced a tendency to higher mortality rate along the study (HR for mortality of 13.5 (95% CI, 1.1-166.7; p = 0.041)]. A higher fat tissue index could be associated with a deleterious effect over right and left ventricular function in dialysis patients.

Mechanisms of kidney dysfunction in the cirrhotic patient: Non-hepatorenal acute-on-chronic kidney damage considerations

Renal dysfunction is a common finding in cirrhotic patients and has a great physiologic, and therefore, prognostic relevance. The combination of liver disease and renal dysfunction can occur as a result of systemic conditions that affect both the liver and the kidney, although primary disorders of the liver complicated by renal dysfunction are much more common. As most of the renal dysfunction scenarios in cirrhotic patients correspond to either prerenal azotemia or hepatorenal syndrome (HRS), physicians tend to conceive renal dysfunction in cirrhotic patients as mainly HRS. However, there are many systemic conditions that may cause both a "baseline" chronic kidney damage and a superimposed kidney dysfunction when this systemic condition worsens. The main aim of this article is to review some of the most important non prerenal non-HRS considerations regarding acute on chronic kidney dysfunction in cirrhotic patients, including renal manifestation of related to non-alcoholic steatohepatitis (NASH) viral hepatitis, the effect of cardiorenal syndrome in cirrhotics and corticosteroid-deficiency associated renal dysfunction.

Deciphering key genes in cardio-renal syndrome using network analysis

Cardio-renal syndrome (CRS) is a rapidly recognized clinical entity which refers to the inextricably connection between heart and renal impairment, whereby abnormality to one organ directly promotes deterioration of the other one. Biological markers help to gain insight into the pathological processes for early diagnosis with higher accuracy of CRS using known clinical findings. Therefore, it is of interest to identify target genes in associated pathways implicated linked to CRS. Hence, 119 CRS genes were extracted from the literature to construct the PPIN network. We used the MCODE tool to generate modules from network so as to select the top 10 modules from 23 available modules. The modules were further analyzed to identify 12 essential genes in the network. These biomarkers are potential emerging tools for understanding the pathophysiologic mechanisms for the early diagnosis of CRS. Ontological analysis shows that they are rich in MF protease binding and endo-peptidase inhibitor activity. Thus, this data help increase our knowledge on CRS to improve clinical management of the disease.

Immunomodulatory Approaches in Diabetes-Induced Cardiorenal Syndromes

Immunomodulatory approaches are defined as all interventions that modulate and curb the immune response of the host rather than targeting the disease itself with the aim of disease prevention or treatment. A better understanding of the immune system continues to offer innovative drug targets and methods for immunomodulatory interventions. Cardiorenal syndrome is a clinical condition that defines disorders of the heart and kidneys, both of which communicate with one another through multiple pathways in an interdependent relationship. Cardiorenal syndrome denotes the confluence of heart-kidney relationships across numerous interfaces. As such, a dysfunctional heart or kidney has the capacity to initiate disease in the other organ via common hemodynamic, neurohormonal, immunological, and/or biochemical feedback pathways. Understanding how immunomodulatory approaches are implemented in diabetes-induced cardiovascular and renal diseases is important for a promising regenerative medicine, which is the process of replacing cells, tissues or organs to establish normal function. In this article, after a brief introduction on the immunomodulatory approaches in diseases, we will be reviewing the epidemiology and classifications of cardiorenal syndrome. We will be emphasizing on the hemodynamic factors and non-hemodynamic factors linking the heart and the kidneys. In addition, we will be elaborating on the immunomodulatory pathways involved in diabetes-induced cardiorenal syndrome namely, RAS, JAK/STAT, and oxidative stress. Moreover, we will be addressing possible therapeutic approaches that target the former pathways in an attempt to modulate the immune system.

Long-term outcomes of autologous skeletal myoblast cell-sheet transplantation for end-stage ischemic cardiomyopathy

We evaluated the cardiac function recovery following skeletal myoblast cell-sheet transplantation and the long-term outcomes after applying this treatment in 23 patients with ischemic cardiomyopathy. We defined patients as “responders” when their left ventricular ejection fraction remained unchanged or improved at 6 months after treatment. At 6 months, 16 (69.6%) patients were defined as responders, and the average increase in left ventricular ejection fraction was 4.9%. The responders achieved greater improvement degrees in left ventricular and hemodynamic function parameters, and they presented improved exercise capacity. During the follow-up period (56 ± 28 months), there were four deaths and the overall 5-year survival rate was 95%. Although the responders showed higher freedom from mortality and/or heart failure admission (5-year, 81% versus 0%; p = 0.0002), both groups presented an excellent 5-year survival rate (5-year, 93% versus 100%; p = 0.297) that was higher than that predicted using the Seattle Heart Failure Model. The stepwise logistic regression analysis showed that the preoperative estimated glomerular filtration rate and the left ventricular end-systolic volume index were independently associated with the recovery progress. Approximately 70% of patients with “no-option” ischemic cardiomyopathy responded well to the cell-sheet transplantation. Preoperative renal and left ventricular function might predict the patients’ response to this treatment.

Intrarenal Doppler ultrasonography reflects hemodynamics and predicts prognosis in patients with heart failure

We aimed to clarify clinical implications of intrarenal hemodynamics assessed by intrarenal Doppler ultrasonography (IRD) and their prognostic impacts in heart failure (HF). We performed a prospective observational study, and examined IRD and measured interlobar renal artery velocity time integral (VTI) and intrarenal venous flow (IRVF) patterns (monophasic or non-monophasic pattern) to assess intrarenal hypoperfusion and congestion in HF patients (n = 341). Seven patients were excluded in VTI analysis due to unclear imaging. The patients were divided into groups based on (A) VTI: high VTI (VTI ≥ 14.0 cm, n = 231) or low VTI (VTI < 14.0 cm, n = 103); and (B) IRVF patterns: monophasic (n = 36) or non-monophasic (n = 305). We compared post-discharge cardiac event rate between the groups, and right-heart catheterization was performed in 166 patients. Cardiac index was lower in low VTI than in high VTI (P = 0.04), and right atrial pressure was higher in monophasic than in non-monophasic (P = 0.03). In the Kaplan–Meier analysis, cardiac event rate was higher in low VTI and monophasic groups (P < 0.01, respectively). In the Cox proportional hazard analysis, the combination of low VTI and a monophasic IRVF pattern was a predictor of cardiac events (P < 0.01). IRD imaging might be associated with cardiac output and right atrial pressure, and prognosis.

Worsening Kidney Function Is the Major Mechanism of Heart Failure in Hypertension: The ALLHAT Study

OBJECTIVES

The authors aimed to quantify the extent to which the effect of antihypertensive drugs on incident heart failure (HF) is mediated by their effect on kidney function.

BACKGROUND

The authors hypothesized that the dynamic change in kidney function is the mechanism behind differences in the rate of incident HF in ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) participants randomized to lisinopril and chlorthalidone, in comparison with those randomized to amlodipine and doxazosin.

METHODS

Causal mediation analysis of ALLHAT data (1994 to 2002) included participants with available baseline and 24- to 48-month estimated glomerular filtration rate (eGFR) (N = 27,918; mean age 66 ± 7.4 years; 32.4% Black, 56.3% men). Change in eGFR was the mediator. Incident symptomatic HF was the primary outcome. Hospitalized/fatal HF was the secondary outcome. Linear regression (for mediator) and logistic regression (for outcome) analyses were adjusted for demographics, cardiovascular disease, and risk factors.

RESULTS

There were 1,769 incident HF events, including 1,359 hospitalized/fatal HF events. In fully adjusted causal mediation analysis, the relative change in eGFR mediated 18% of the effect of chlorthalidone, and 33% of lisinopril on incident symptomatic HF, and 25% of the effect of chlorthalidone, and 41% of lisinopril on hospitalized/fatal HF. In participants with diabetes, the relative change in eGFR mediated nearly 50% of the effect of lisinopril on incident symptomatic HF, whereas in diabetes-free participants, only 17%.

CONCLUSIONS

On the risk difference scale, change in eGFR accounts for up to 50% of the mechanism by which antihypertensive medications affect HF. (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial [ALLHAT]; NCT00000542).

Neural tone and cardio-renal outcomes in patients with type 2 diabetes mellitus: a review of the literature with a focus on SGLT2 inhibitors

Recent clinical trials involving the systemic effects of sodium-glucose cotransporter 2 inhibitors (SGLT2i) have revealed beneficial outcomes pertaining to the microvascular sequelae of type 2 diabetes mellitus (T2DM) such as nephropathy, as well as macrovascular effects such as major adverse cardiovascular effects (MACE). Such findings have spurred the elevation of these agents to level A-tiers of recommendation within clinical guidelines addressing the management of complicated T2DM. While the mechanisms of SGLTi (-flozin drugs) are still being elucidated, a paucity of data exists within the literature appraising the role of neuromodulation and associated mechanisms in the aforementioned outcome studies. Given the role of the nervous system in orchestrating the pathologic processes that hamper cardio-renal status, insight into this topic offers an expanded perspective on T2DM. In this review we investigate the mechanisms by which SGLTi improve cardio-renal function in T2DM patients with emphases on neural tone and nervous system physiology.

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.

Usefulness of Peritoneal Ultrafiltration in Patients with Diuretic Resistant Heart Failure without End-Stage Renal Disease

AIM

This study aimed to explore the role of peritoneal ultrafiltration (UF) in cardiorenal syndrome (CRS) patients for fluid and metabolic control.

BACKGROUND

Peritoneal UF is safely and efficiently used for the management of CRS. It has been shown to provide efficient UF in hypervolemic patients.

METHODS

Thirty (20 males and 10 females) CRS patients were treated by peritoneal dialysis (PD) and UF. The baseline data of the patients (demographics, causes of heart failure, the presence of pacemaker or implantable cardioverter-defibrillator, the need for extracorporeal UF or paracentesis or thoracentesis, comorbidity, drugs, left ventricular ejection fraction [LVEF] and pulmonary artery systolic pressure [PAPs], pericardial effusion, physical examination, body weight, NYHA class, dialysis regime, urine output, N-terminal pro-B-type natriuretic peptide [NT-proBNP] level, hemoglobin, estimated glomerular filtration rate [eGFR], and other routine biochemical determinations) were recorded at the onset, every 6 months, and then annually. Echocardiograms were performed at baseline and after 6 and 12 months. The time points of complications associated with PD, the need for hemodialysis, the day of death, and causes of death were documented.

RESULTS

Mean age was 69 ± 8 years (range 49-84 years). The average PD duration was 18.25 ± 14.87 months. According to the CKD-EPI, initial mean GFR was 34.34 ± 11.9 mL/min/1.73 m2 (range 16.57-59.0), and this increased to 45.48 ± 26.04, 45.10 ± 28.58, and 41.10 ± 25.68 mL/min/1.73 m2 in the third, sixth, and twelfth months, respectively. There was a significant increase in the first 3 months and a significant decrease between the third and twelfth months (respectively, p = 0.018 and p = 0.043). There was no difference in eGFR levels between baseline and the end of the first year (p = 0.217). In the first 3 months, there was a significant decline in urea levels to 79.38 ± 36.65 from 109.92 ± 42.44 mg/dL and this was maintained until the end of the first year of PD therapy (after 3 months, p = 0.002; after 1 year, p = 0.024). However, there was no significant change in creatinine levels within the first year (p = 0.312). There was a significant increase in hemoglobin level up to the end of the first year of PD (after 3 months, p = 0.000; after 12 months, p = 0.013). There was a marked decrease in NT-proBNP levels in the first 6 months (p = 0.011). Functional capacity (according to NYHA classification) improved in all patients by the third month of PD treatment (p < 0.001). This early improvement was maintained in many patients during the following 12 months (p < 0.001). There was a marked decrease in NT-proBNP levels in the first 6 months (p = 0.011). At the end of the first year, there was an approximate 15% reduction in NT-proBNP levels (p = 0.647). Hospitalizations decreased to 6 ± 15 days/patient-year (range 18-122 days) from 62 ± 24 days/patient-year (p = 0.000).

CONCLUSION

Peritoneal UF is a treatment method that maintains renal function and electrolyte balance, improves cardiac function, and reduces hospitalizations in CRS patients. We observed that this treatment significantly increased functional capacity and quality of life and significantly reduced hospital admissions.

Cardiorenal Syndrome in Type 2 Diabetes Mellitus - Rational Use of Sodium-glucose Cotransporter-2 Inhibitors

Cardiorenal syndrome (CRS) in people with type 2 diabetes mellitus (T2DM) illustrates the bidirectional link between the heart and the kidneys, with acute or chronic dysfunction of one organ adversely impacting the function of the other. Of the five subtypes identified, type 1 and 2 CRS occur because of the adverse impact of cardiac conditions on the kidneys. Type 3 and 4 occur when renal conditions affect the heart, and in type 5, systemic conditions impact the heart and kidneys concurrently. The cardiovascular and renoprotective benefits evidenced with sodium-glucose cotransporter-2 (SGLT2) inhibitors make them a potential choice in the management of CRS. Cardiovascular protection is mediated by a reduction in cardiac workload, blood pressure, and body weight; with improvement in lipid profile, uric acid levels, and adaptive ketogenesis process. Renoprotection is facilitated by reduction in albuminuria and hypoxic stress, and restoration of tubuloglomerular feedback. The favourable effect on cardiovascular complications and death, as well as renal complications and progression to end-stage kidney disease, has been confirmed in clinical trials. Guidelines endorse first-line use of SGLT2 inhibitors after metformin in patients with T2DM with high cardiovascular risk, chronic kidney disease or both. Since most trials with SGLT2 inhibitors excluded subjects with acute illness, patients with CRS subtypes 1 and 3 have not been studied adequately, making SGLT2 initiation in clinical practice challenging. Ongoing trials may provide evidence for SGLT2 inhibitor use in CRS. This review aims to enhance understanding of CRS and provide guidance for judicious use of SGLT2 inhibitors in T2DM.

Novel risk models to predict acute kidney disease and its outcomes in a Chinese hospitalized population with acute kidney injury

Acute kidney disease (AKD) is a state between acute kidney injury (AKI) and chronic kidney disease (CKD), but the prognosis of AKD is unclear and there are no risk-prediction tools to identify high-risk patients. 2,556 AKI patients were selected from 277,898 inpatients of three affiliated hospitals of Central South University from January 2015 to December 2015. The primary point was whether AKI patients developed AKD. The endpoint was death or end stage renal disease (ESRD) 90 days after AKI diagnosis. Multivariable Cox regression was used for 90-day mortality and two prediction models were established by using multivariable logistic regression. Our study found that the incidence of AKD was 53.17% (1,359/2,556), while the mortality rate and incidence of ESRD in AKD cohort was 19.13% (260/1,359) and 3.02% (41/1,359), respectively. Furthermore, adjusted hazard ratio of mortality for AKD versus no AKD was 1.980 (95% CI 1.427–2.747). In scoring model 1, age, gender, hepatorenal syndromes, organic kidney diseases, oliguria or anuria, respiratory failure, blood urea nitrogen (BUN) and acute kidney injury stage were independently associated with AKI progression into AKD. In addition, oliguria or anuria, respiratory failure, shock, central nervous system failure, malignancy, RDW-CV ≥ 13.7% were independent risk factors for death or ESRD in AKD patients in scoring model 2 (goodness-of fit, P₁ = 0.930, P₂ = 0.105; AUROC₁ = 0.879 (95% CI 0.862–0.896), AUROC₂ = 0.845 (95% CI 0.813–0.877), respectively). Thus, our study demonstrated AKD was independently associated with increased 90-day mortality in hospitalized AKI patients. A new prediction model system was able to predict AKD following AKI and 90-day prognosis of AKD patients to identify high-risk patients.

Clinical Application of Melatonin in the Treatment of Cardiovascular Diseases: Current Evidence and New Insights into the Cardioprotective and Cardiotherapeutic Properties

Cardiovascular diseases (CVDs) are the leading global cause of mortality and disability, tending to happen in younger individuals in developed countries. Despite improvements in medical treatments, the therapy and long-term prognosis of CVDs such as myocardial ischemia-reperfusion, atherosclerosis, heart failure, cardiac hypertrophy and remodeling, cardiomyopathy, coronary artery disease, myocardial infarction, and other CVDs threatening human life are not satisfactory enough. Therefore, many researchers are attempting to identify novel potential therapeutic methods for the treatment of CVDs. Melatonin is an anti-inflammatory and antioxidant agent with a wide range of therapeutic properties. Recently, several investigations have been carried out to evaluate its effectiveness and efficiency in CVDs therapy, focusing on mechanistic pathways. Herein, this review aims to summarize current findings of melatonin treatment for CVDs.

Kidney injury as post-interventional complication of TAVI

Transcatheter aortic valve implantation (TAVI) is an accepted treatment approach of aortic stenosis. In the beginning, this technique was executed in high-risk patients only. Today, intermediate-risk patients are also amenable for TAVI, as long as the transfemoral approach is chosen. Numerous predictors have been identified that could lead to periprocedural complications and are defined by patient co-morbidities as well as being inherent to the technical approach. Although vascular complications and postinterventional paravalvular regurgitation have been minimized over the past years by revised technologies and techniques, there is a prevailing individual risk brought about by the specific pathophysiology of the cardiorenal syndrome.

Defining an Intraoperative Hypotension Threshold in Association with De Novo Renal Replacement Therapy after Cardiac Surgery

BACKGROUND

Acute kidney injury (AKI) is a frequent and deadly complication after cardiac surgery. In the absence of effective therapies, a focus on risk factor identification and modification has been the mainstay of management. The authors sought to determine the impact of intraoperative hypotension on de novo postoperative renal replacement therapy in patients undergoing cardiac surgery, hypothesizing that prolonged periods of hypotension during and after cardiopulmonary bypass (CPB) were associated with an increased risk of renal replacement therapy.

METHODS

Included in this single-center retrospective cohort study were adult patients who underwent cardiac surgery requiring CPB between November 2009 and April 2015. Excluded were patients who were dialysis dependent, underwent thoracic aorta or off-pump procedures, or died before receiving renal replacement therapy. Degrees of hypotension were defined by mean arterial pressure (MAP) as less than 55, 55 to 64, and 65 to 74 mmHg before, during, and after CPB. The primary outcome was de novo renal replacement therapy.

RESULTS

Of 6,523 patient records, 336 (5.2%) required new postoperative renal replacement therapy. Each 10-min epoch of MAP less than 55 mmHg post-CPB was associated with an adjusted odds ratio of 1.13 (95% CI, 1.05 to 1.23; P = 0.002), and each 10-min epoch of MAP between 55 and 64 mmHg post-CPB was associated with an adjusted odds ratio of 1.12 (95% CI, 1.06 to 1.18; P = 0.0001) for renal replacement therapy. The authors did not observe an association between hypotension before and during CPB with renal replacement therapy.

CONCLUSIONS

MAP less than 65 mmHg for 10 min or more post-CPB is associated with an increased risk of de novo postoperative renal replacement therapy. The association between intraoperative hypotension and AKI was weaker in comparison to factors such as renal insufficiency, heart failure, obesity, anemia, complex or emergent surgery, and new-onset postoperative atrial fibrillation. Nonetheless, post-CPB hypotension is a potentially easier modifiable risk factor that warrants further investigation.

The Cardiorenal Syndrome: Mechanistic Insights and Prognostication with Soluble Biomarkers

PURPOSE OF REVIEW

To characterize and interpret recent studies of biomarkers of cardiorenal syndrome.

RECENT FINDINGS

Recent studies have questioned the mechanisms and significance of moderate worsening renal function (WRF) in patients with acute heart failure. In the setting of successful decongestion, WRF may not predict cardiorenal morbidity. Cardiac-specific biomarkers including cardiac troponins and natriuretic peptides are highly prognostic in acute and chronic HF patients with kidney impairment, and serial changes in these markers during hospitalization are also predictive of longer-term adverse outcomes. These markers also predict new HF in patients with established chronic kidney disease (CKD). The role of kidney tubular injury markers in acute HF remains controversial, with inconsistent associations with short- and long-term cardiorenal outcomes. Many cases of WRF in acute HF are not characterized by a clear pattern of renal tubular injury. Cardiac-specific and renal-specific biomarkers may provide mechanistic and prognostic information in cardiorenal syndromes.

Cardiorenal syndrome in thalassemia patients

Background

Cardiorenal syndrome (CRS), a serious condition with high morbidity and mortality, is characterized by the coexistence of cardiac abnormality and renal dysfunction. There is limited information about CRS in association thalassemia. This study aimed to investigate the prevalence of CRS in thalassemia patients and also associated risk factors.

Methods

Thalassemia patients who attended the out-patient clinic of a tertiary care university hospital from October 2016 to September 2017 were enrolled onto this cross-sectional study. Clinical and laboratory findings from 2 consecutive visits, 3 months apart, were assessed. The criteria for diagnosis of CRS was based on a system proposed by Ronco and McCullough. Cardiac abnormalities are assessed by clinical presentation, establishment of acute or chronic heart failure using definitions from 2016 ESC guidelines or from structural abnormalities shown in an echocardiogram. Renal dysfunction was defined as chronic kidney disease according to the 2012 KDIGO guidelines.

Results

Out of 90 thalassemia patients, 25 (27.8%) had CRS. The multivariable analysis showed a significant association between CRS and extramedullary hematopoiesis (EMH) (odds ratio (OR) 20.55, p = 0.016); thalassemia type [β⁰/β^E vs β⁰/β⁰ thalassemia (OR 0.005, p = 0.002)]; pulmonary hypertension (OR 178.1, p = 0.001); elevated serum NT-proBNP (OR 1.028, p = 0.022), and elevated 24-h urine magnesium (OR 1.913, p = 0.016). There was no association found between CRS and frequency of blood transfusion, serum ferritin, liver iron concentration, cardiac T2*, type of iron chelating agents, or urine neutrophil gelatinase-associated lipocalin level.

Conclusions

CRS is relatively common in thalassemia patients. Its occurrence is associated with laboratory parameters which are easily measured in clinical practice.

Prevalence, types, risk factors, and outcomes of cardiorenal syndrome in a rural population of central India: A cross-sectional study

Background and Objectives:

Heart failure leading to renal dysfunction and vice-versa termed as Cardio-Renal Syndrome(CRS) has now been increasingly identified as a marker of higher morbidity and mortality. Till date, there is limited data available regarding clinical profile, associated risk factors and outcome of CRS in rural population of central India. This study was conducted to elucidate the prevalence, risk factors, and outcome of CRS and its types.

Methods:

This was a single-centric, cross-sectional study conducted amongst the patients admitted to medicine wards and ICCU from October 2017 to September 2019. Classification given by RONCO et al. in 2008 was used for classifying CRS patients into various types. Cross-sectional data was used to find the prevalence, risk factors and their inter-relationship with outcome and mortality. STATA software was used for statistical analysis.

Results:

Out of 96 CRS patients, 47(48.96%) were Type 1, 22 (22.92%) were type 2, 19(19.79%) were type 4 and 3 (3.13% ) were type 3, and 5 (5.21%) were of type 5. Most common risk factor was Hypertension (HTN) found in 46 (47.92%), followed closely by Coronary Artery Disease (CAD) and anaemia. Mortality was seen in 44(45.83%) of CRS patients and it was significantly high. High mortality was common in patients of types 3 and type 5 CRS. Risk factors like HTN, CAD, smoking, reduced glomerular filtration rate, low ejection fraction and sepsis were significantly associated with worse outcomes across all CRS sub-types.

Interpretation and Conclusions:

There is high mortality among CRS. Prevention or optimal management of HTN, CAD and sepsis is required to decrease mortality. There is need for more population based studies for confirming our study findings.

Role of sodium glucose co-transporter 2 inhibitors in patients with heart failure: an elusive mechanism

Heart failure (HF) is a major cause of morbidity and mortality worldwide, and the burden of HF continues to rise. There has been an interest in sodium-glucose co-transporter-2 (SGLT2) inhibitors for their role in reducing HF hospitalizations in pivotal trials. Since these agents were approved by the Food and Drug Administration for the management of diabetes mellitus, multiple small trials and analyses have tried to explain the underlying beneficial mechanisms in HF . In this review, we discuss different mechanisms by which SGLT2 inhibitors play hemodynamic, metabolic, and cellular roles in different HF phenotypes. We also address issues pertaining to the safety of these relatively newer agents.KEY MESSAGESSGLT2 inhibitors are associated with a reduction in HF hospitalizations in both diabetics and non-diabetics.The beneficial role of SGLT2 inhibitors in reducing HF hospitalization is observed among participants with established cardiovascular disease/HF and at-risk population.SGLT2 inhibitors pose an important role in renal protection, another mechanism by which these medications can be helpful in HF patients.

Patients with moderate chronic kidney disease without heart disease have reduced coronary flow velocity reserve

Aims

The overall aim was to identify sub‐clinical cardiac abnormalities by echocardiography in patients with chronic kidney disease (CKD) stages 3 and 4 and to investigate underlying mechanisms.

Methods and results

Ninety‐one patients with CKD stages 3 and 4, without a diagnosis of heart disease, and 41 healthy matched controls were included in this cross‐sectional study. Cardiac morphology and function were analysed with Doppler echocardiography and coronary flow velocity reserve (CFVR) in response to adenosine was measured in the left anterior descendent artery to detect coronary microvascular dysfunction (CMD). All study subjects had a left ventricular (LV) ejection fraction > 50%. Patients with CKD showed statistically significant increases in left atrial volume index and transmitral and pulmonary vein flow velocities during atrial contraction and prolonged LV isovolumetric relaxation time. Patients with CKD had significantly reduced CFVR vs. controls (2.74 ± 0.86 vs. 3.40 ± 0.89, P < 0.001), and 43% of patients were classified as having CMD compared with 9% of controls (P = 0.001).

Conclusions

Patients with CKD stages 3 and 4, without a diagnosis of heart disease, showed early abnormalities in LV diastolic function that did not fulfil the criteria for LV dysfunction according to current guidelines. A large proportion of CKD patients had CMD, suggesting that microvascular abnormalities may have a pathogenic role in the development of heart failure in this patient group.

Cardiovascular System Affection and Its Relation to First-Year Mortality in Patients Initiating Maintenance Hemodialysis

Background

The incidence of end-stage renal disease (ESRD) has increased by 30–40% in the last decade. These patients have a higher mortality rate of 3–8 times compared to the general population. In the present study, we aimed to detect cardiovascular complications and their relation to the first-year mortality rate in patients on hemodialysis in Aswan University Hospital, upper Egypt.

Patients and Methods

Our study was a cross-sectional study which was done at the hemodialysis unit in Aswan University Hospital from May 2016 to May 2018. The study included 100 patients with ESRD on regular hemodialysis (first year on programmed hemodialysis). All patients were subjected to full clinical examination and laboratory studies includngd complete blood count (CBC), kidney function tests, serum calcium and phosphorus level, parathormone (PTH) hormone, serum albumin level, C-reactive protein (CRP), echocardiography and electrocardiogram (ECG), and lateral abdominal x-ray for detection of aortic calcification. 

Results

The present study included 47 males and 53 females, with a mean age of 50.6 ±13.89 years. The main risk factors for patients with ESRD were hypertension (48%) followed by diabetic nephropathy (36%), glomerulonephritis (15%), idiopathic etiology (11%), obstructive uropathy (8%), lupus nephritis (6%), polycystic kidney disease (4%) and cardio renal syndrome (1%). Twenty-seven deaths have been noted during the first year of dialysis treatment. The leading causes of death were cardio-vascular events (66, 67%), infection (22, 22%) and malignancy (11, 11%), The most common cardiovascular events were myocardial infarction (27.8%), sudden cardiac death (SCD) (27.8%) and heart failure (22.2%).

Conclusion

In conclusion, our study showed that the main risk factors for ESRD patients in Aswan University Hospital are hypertensive nephrosclerosis, diabetic nephropathy, glomerulonephritis and idiopathic etiology, and the main causes of first-year mortality were cardiovascular events followed by infection and malignancy.

Cardiorenal Syndrome in Renal Transplant Recipients: Prevalence, Clinical Presentation, Treatment, and Outcome

BACKGROUND

Data on the cardiorenal syndrome (CRS) in renal transplant recipients (RTR) are scarce. We investigated the prevalence, clinical presentation, treatment, and outcomes of patients with CRS in our renal transplant cohort.

METHODS

Charts and medical records of adult RTR were investigated to identify patients with renal allograft dysfunction and heart failure (HF) with reduced (HFrEF) or preserved (HFpEF) ejection fraction.

RESULTS

From December 2009 to December 2019, a total of 1,610 patients received a kidney allograft at our institution. CRS was diagnosed in 9 patients (0.56%) a median of 11 years after transplantation (4-20 years). Seven of the patients were male, and 2 were female. The median age when CRS was diagnosed was 71 years (64-80 years). The major presenting symptom was dyspnea. Five patients had HFrEF, and 4 had HFpEF. The patient's median basal creatinine clearance was 37 mL/min (range 29-77 mL/min). At hospitalization, it was decreased to 24 mL/min (range 13-45 mL/min). The patients were treated with diuretics, but 5 of them required extracorporeal fluid removal. At the 16-month follow-up (median), all patients with HFpEF were alive and had returned to initial levels of creatinine clearance. Two of the 5 HFrEF had died, and 2 needed permanent extracorporeal water removal.

CONCLUSION

CRS after renal transplantation was rare (<1.0%), but CRS in HFreF patients was associated with a poor outcome.

Canine Traditional Laboratory Tests and Cardiac Biomarkers

In small animals, cardiac disease evaluation through laboratory tests can be a challenge. This review will present both historical and updated perspectives on the clinical pathology of cardiac diseases in dogs and demonstrate that laboratory tests are useful tools for the management of patients with cardiac diseases.

Overestimation of glomerular filtration rate by creatinine-based equation in heart failure patients is predicted by a novel scoring system

AIMS

Creatinine-based estimated glomerular filtration rate (eGFRcre) has been shown to overestimate the glomerular filtration rate (GFR) when it is compared with cystatin C-based estimated GFR (eGFRcys) in older people. We investigated clinical determinants of GFR overestimation by eGFRcre and developed a score for prediction of GFR overestimation (OE) in heart failure patients.

METHODS

We retrospectively examined 244 Japanese heart failure patients (aged 72.2 ± 13.1 years; 48% women) who had no known extrarenal factors that affect serum cystatin C concentration. eGFR OE by eGFRcre was defined as eGFRcre being ≥120% of cystatin C-based eGFR.

RESULTS

The proportion of heart failure patients with OE was 14.3%. Patients with OE were older, had lower body weight and total skeletal muscle mass than those in patients without OE. Laboratory examinations showed that hemoglobin concentration was lower, and the ratio of blood urea nitrogen-to-creatinine was higher in patients with OE than in patients without OE. In multivariate regression analysis, body weight (<63.0 kg in men and <42.0 kg in women), hemoglobin level (<12.4 g/dL in men and <11.0 g/dL in women) and ratio of blood urea nitrogen-to-creatinine (>26.5) in addition to skeletal muscle mass were independently associated with OE. A score calculated by using cut-off levels of body weight, hemoglobin concentration and ratio of blood urea nitrogen-to-creatinine predicted OE with a sensitivity of 97.1% and a specificity of 98.1%.

CONCLUSION

Overestimation of GFR by eGFRcre is predictable by a novel scoring system, which might be useful for the detection of patients who require cystatin C-based eGFR measurement for accurate assessment of renal function. Geriatr Gerontol Int 2020; 20: 752-758.

New insights into the pathophysiological mechanisms underlying cardiorenal syndrome

Communication between the heart and kidney occurs through various bidirectional pathways. The heart maintains continuous blood flow through the kidney while the kidney regulates blood volume thereby allowing the heart to pump effectively. Cardiorenal syndrome (CRS) is a pathologic condition in which acute or chronic dysfunction of the heart or kidney induces acute or chronic dysfunction of the other organ. CRS type 3 (CRS-3) is defined as acute kidney injury (AKI)-mediated cardiac dysfunction. AKI is common among critically ill patients and correlates with increased mortality and morbidity. Acute cardiac dysfunction has been observed in over 50% of patients with severe AKI and results in poorer clinical outcomes than heart or renal dysfunction alone. In this review, we describe the pathophysiological mechanisms responsible for AKI-induced cardiac dysfunction. Additionally, we discuss current approaches in the management of patients with CRS-3 and the development of targeted therapeutics. Finally, we summarize current challenges in diagnosing mild cardiac dysfunction following AKI and in understanding CRS-3 etiology.

The Value of a Cystatin C-based Estimated Glomerular Filtration Rate for Cardiovascular Assessment in a General Japanese Population: Results From the Iwate Tohoku Medical Megabank Project

BACKGROUND

Epidemiological studies have shown that high circulating cystatin C is associated with a risk of cardiovascular disease (CVD) independent of creatinine-based renal function measurements. The present study investigated the comparison between the cystatin C-based estimated glomerular filtration rate (GFRcys) and creatinine-based GFR (GFRcr) to determine whether these measurements are associated with CV biomarkers and elevated CVD risk in a general Japanese population.

METHODS

The Iwate Tohoku Medical Megabank Organization pooled individual participant data from a general population-based cohort study in Iwate prefecture (n = 29,375). Chronic kidney disease (CKD) was estimated using the GFRcys, GFRcr and the urine albumin-to-creatinine ratio (UACR).

RESULTS

The prevalence of CKD in the participants was found to be higher based on the GFRcr than the GFRcys. Multiple variable analyses after adjusting for baseline characteristics showed that high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were associated with the GFRcys. The area under the receiver operating characteristic (AUROC) curve for identifying individuals with a high Suita score was higher for the GFRcys (AUROC = 0.68) than it was for the GFRcr (AUROC = 0.64, P < 0.001). The GFRcys provided reclassification improvement for the CVD risk prediction model by the GFRcr (net reclassification improvement = 0.341; integrated discrimination improvement = 0.018, respectively, P < 0.001).

CONCLUSIONS

The GFRcys is more closely associated with CV biomarkers, including hs-cTnT and NT-proBNP levels, and a high Suita score than the GFRcr, and it provides additional value in the assessment of CVD risk using GFRcr.

Benefits of peritoneal ultrafiltration in HFpEF and HFrEF patients

Background

Peritoneal ultrafiltration (pUF) in refractory heart failure (HF) reduces the incidence of decompensation episodes, which is of particular significance as each episode incrementally adds to mortality. Nevertheless, there are insufficient data about which patient cohort benefits the most. The objective of this study was to compare pUF in HFrEF and HFpEF, focusing on functional status, hospitalizations, surrogate endpoints and mortality.

Methods

This study involves 143 patients, who could be classified as either HFpEF (n = 37, 25.9%) or HFrEF (n = 106, 74.1%) and who received pUF due to refractory HF.

Results

Baseline eGFR was similar in HFrEF (23.1 ± 10.6 mg/dl) and HFpEF (27.8 ± 13.2 mg/dl). Significant improvements in NYHA class were found in HFpEF (3.19 ± 0.61 to 2.72 ± 0.58, P <  0.001) and HFrEF (3.45 ± 0.52 to 2.71 ± 0.72, P <  0.001). CRP decreased in HFrEF (19.4 ± 17.6 mg/l to 13.7 ± 21.4 mg/l, P = 0.018) and HFpEF (33.7 ± 52.6 mg/l to 17.1 ± 26.3 mg/l, P = 0.004). Body weight was significantly reduced in HFrEF (81.1 ± 14.6 kg to 77.2 ± 15.6 kg, P = 0.003) and HFpEF (86.9 ± 15.8 kg to 83.1 ± 15.9 kg, P = 0.005). LVEF improved only in HFrEF (25.9 ± 6.82% to 30.4 ± 12.2%, P = 0.046). BCR decreased significantly in HFrEF and HFpEF (55.7 ± 21.9 to 34.3 ± 17.9 P > 0.001 and 50.5 ± 68.9 to 37.6 ± 21.9, P = 0.006). Number of hospitalization episodes as well as number of hospitalization days decreased significantly only in HFpEF (total number 2.88 ± 1.62 to 1.25 ± 1.45, P <  0.001, days 40.4 ± 31.7 to 18.3 ± 22.5 days, P = 0.005).

Conclusions

pUF offers various benefits in HFpEF and HFrEF, but there are also substantial differences. In particular, hospitalization rates were found to be significantly reduced in HFpEF patients, indicating a greater medical and economical advantage. However, LVEF was only found to be improved in HFrEF patients. While pUF can now be regarded as an option to supplement classical HF therapy, further studies are desirable to obtain specifications about pUF in HFpEF, HFmEF and HFrEF patients.

Cardiorenal syndrome: Multi-organ dysfunction involving the heart, kidney and vasculature

Cardiorenal syndrome (CRS) is a multi-organ disease, encompassing heart, kidney and vascular system dysfunction. CRS is a worldwide problem, with high morbidity, mortality, and inflicts a significant burden on the health care system. The pathophysiology is complex, involving interactions between neurohormones, inflammatory processes, oxidative stress and metabolic derangements. Therapies remain inadequate, mainly comprising symptomatic care with minimal prospect of full recovery. Challenges include limiting the contradictory effects of multi-organ targeted drug prescriptions and continuous monitoring of volume overload. Novel strategies such as multi-organ transplantation and innovative dialysis modalities have been considered but lack evidence in the CRS context. The adjunct use of pharmaceuticals targeting alternative pathways showing positive results in preclinical models also warrants further validation in the clinic. In recent years, studies have identified the involvement of gut dysbiosis, uraemic toxin accumulation, sphingolipid imbalance and other unconventional contributors, which has encouraged a shift in the paradigm of CRS therapy.

Neutrophil gelatinase-associated lipocalin does not predict acute kidney injury in heart failure

BACKGROUND

Acute cardiorenal syndrome type 1 (CRS-1) is defined by a rapid cardiac dysfunction leading to acute kidney injury (AKI). Neutrophil gelatinase-associated lipocalin (NGAL) is expressed on the surface of human neutrophils and epithelial cells, such as renal tubule cells, and its serum (sNGAL) and urinary have been used to predict AKI in different clinical settings.

AIM

To characterize CRS-1 in a cohort of patients with acute heart diseases, evaluating the potentiality of sNGAL as an early marker of CRS-1.

METHODS

We performed a retrospective cohort, multi-centre study. From January 2010 to December 2011, we recruited 202 adult patients admitted to the coronary intensive care unit (CICU) with a diagnosis of acute heart failure or acute coronary syndrome. We monitored the renal function to evaluate CRS-1 development and measured sNGAL levels within 24 h and after 72 h of CICU admission.

RESULTS

Overall, enrolled patients were hemodynamically stable with a mean arterial pressure of 92 (82-107) mmHg, 55/202 (27.2%) of the patients developed CRS-1, but none of them required dialysis. Neither the NGAL delta value (AUC 0.40, 95%CI: 0.25-0.55) nor the NGAL peak (AUC 0.45, 95%CI: 0.36-0.54) or NGAL cut-off (≥ 140 ng/mL) values were statistically significant between the two groups (CRS-1 vs no-CRS1 patients). The area under the ROC curve for the prediction of CRS-1 was 0.40 (95%CI: 0.25-0.55) for the delta NGAL value and 0.45 (95%CI: 0.36-0.54) for the NGAL peak value. Finally, in multivariate analysis, the risk of developing CRS-1 was correlated with age > 60 years, urea nitrogen at admission and 24 h-urine output (AUC 0.83, SE = 60.5% SP = 93%), while sNGAL was not significantly correlated.

CONCLUSION

In our population, sNGAL does not predict CRS-1, probably as a consequence of the mild renal injury and the low severity of heart disease. So, these data might suggest that patient selection should be taken into account when considering the utility of NGAL measurement as a biomarker of kidney damage.

A role for the Reitan catheter pump for percutaneous cardiac circulatory support of patients presenting acute congestive heart failure with low output and renal dysfunction?

Outcomes in acute decompensated heart failure remain poor, in particular when patients present with impaired renal function. Recent results indicate that treatment of acute decompensated heart failure patients with the Reitan catheter pump not only increases cardiac index, but also improves renal function resulting in maintained increase of diuresis. These favorable effects were achieved without significant hemolysis, bleeding or vascular complications suggesting that Reitan catheter pump treatment has the potential to facilitate recovery from acute decompensated heart failure with low output and complicated by renal dysfunction.

Human Epididymis Protein 4 as an Indicator of Acute Heart Failure in Patients with Chronic Kidney Disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death in patients with chronic kidney disease (CKD).

OBJECTIVE

To assess whether human epididymis protein 4 (HE4) can be useful in diagnosing acute heart failure (AHF) in patients with CKD.

METHODS

A cohort of 139 Han nationality female patients with CKD who were hospitalized at Renmin Hospital of Wuhan University, Wuhan, China from January 2015 through November 2017 were included.

RESULTS

Multivariable linear regression analysis showed that HE4 levels were significantly associated with N-terminal pro b-type natriuretic peptide (NT-proBNP) after adjustment of kidney function and other confounding factors. In the multivariate logistic regression analysis, HE4 was independently associated with AHF in patients with CKD (odds ratio, 2.120; 95% confidence interval, 1.034-4.344; P = .04). Moreover, according to the optimal cutoff value of 639.6 pmol per L, the area under the curve, sensitivity, and specificity of HE4 were 0.729, 74.2%, and 76.8%, respectively.

CONCLUSIONS

During hospitalization, HE4 maybe an useful indicator for diagnosing AHF in patients with CKD.

Cardiorenal syndrome in heart failure with preserved ejection fraction-an under-recognized clinical entity

Cardiorenal syndrome (CRS) results from the complex and bidirectional interaction between the failing heart and the kidneys. Limited information exists about the pathophysiology and treatment options for worsening kidney function in the setting of heart failure with preserved ejection fraction (HFpEF). This review summarizes the salient pathophysiological pathways in CRS in patients with HFpEF, with emphasis on type 1 and type 2 phenotypes, and outlines diagnostic and therapeutic strategies that are applicable in this population. Elevated central venous and intra-abdominal pressure, left ventricular hypertrophy, LV strain, RAAS activation, oxidative injury, pulmonary hypertension, and RV dysfunction play key roles in the pathogenesis of CRS in the backdrop of HFpEF. The availability of biomarkers of renal and cardiac injury offer a new dimension in accurately diagnosing and quantifying end organ damage in CRS and will improve the accuracy of goal-directed therapies in this population. Novel targeted therapies such as the development of angiotensin/neprilysin inhibitors and sodium-glucose cotransporter-2 (SGLT-2) inhibitors offer new territory in realizing potential benefits in reduction of cardio-renal adverse outcomes in this population. Future studies focusing exclusively on renal outcomes in patients with HFpEF are crucial in delivering optimal therapies in this subset of patients.

Inhibition of apoptosis signal-regulating kinase 1 ameliorates left ventricular dysfunction by reducing hypertrophy and fibrosis in a rat model of cardiorenal syndrome

BACKGROUND

Cardiorenal syndrome (CRS) is a major health burden worldwide in need of novel therapies, as current treatments remain suboptimal. The present study assessed the therapeutic potential of apoptosis signal-regulating kinase 1 (ASK1) inhibition in a rat model of CRS.

METHODS

Adult male Sprague-Dawley rats underwent surgery for myocardial infarction (MI) (week 0) followed by 5/6 subtotal nephrectomy (STNx) at week 4 to induce to induce a combined model of heart and kidney dysfunction. At week 6, MI + STNx animals were randomized to receive either 0.5% carboxymethyl cellulose (Vehicle, n = 15, Sham = 10) or G226 (15 mg/kg daily, n = 11). Cardiac and renal function was assessed by echocardiography and glomerular filtration rate (GFR) respectively, prior to treatment at week 6 and endpoint (week 14). Haemodynamic measurements were determined at endpoint prior to tissue analysis.

RESULTS

G226 treatment attenuated the absolute change in left ventricular (LV) fractional shortening and posterior wall thickness compared to Vehicle. G226 also attenuated the reduction in preload recruitable stroke work. Increased myocyte cross sectional area, cardiac interstitial fibrosis, immunoreactivity of cardiac collagen-I and III and cardiac TIMP-2 activation, were significantly reduced following G226 treatment. Although we did not observe improvement in GFR, G226 significantly reduced renal interstitial fibrosis, diminished renal collagen-I and -IV, kidney injury molecule-1 immunoreactivity as well as macrophage infiltration and SMAD2 phosphorylation.

CONCLUSION

Inhibition of ASK1 ameliorated LV dysfunction and diminished cardiac hypertrophy and cardiorenal fibrosis in a rat model of CRS. This suggests that ASK1 is a critical pathway with therapeutic potential in the CRS setting.

Impact of left ventricular dysfunction and fluid balance on the outcomes of patients with sepsis

OBJECTIVE

Left ventricular (LV) dysfunction is a predictor of mortality in patients with sepsis. However, whether the adverse impact of LV dysfunction depends on fluid balance remains unclear. We retrospectively investigated the impact of LV dysfunction and fluid balance on various outcomes of patients with sepsis.

METHODS

Critically ill patients with sepsis were classified according to their LV function: normal LV function, diastolic dysfunction (septal e' of <10 and E/e' of ≥15 with ejection fraction of ≥50%), and systolic dysfunction (ejection fraction of <50%).

RESULTS

There were 83 (51.2%) patients with normal LV function, 39 (24.1%) with diastolic dysfunction, and 40 (24.7%) with systolic dysfunction. The cumulative and daily fluid balances after intensive care unit admission did not differ. However, acute kidney injury was more prevalent in the patients with diastolic and systolic dysfunction than in those with normal LV function (82.1%, 87.5%, and 69.9%, respectively; P = 0.065). LV dysfunction lengthened the duration of renal replacement therapy, independent of baseline renal dysfunction and the daily fluid balance (P = 0.008). Moreover, both diastolic and systolic dysfunction were associated with mortality (hazard ratio: 2.7 and 3.0; P = 0.047 and P = 0.028, respectively), regardless of the daily fluid balance, which was also a significant predictor of mortality (P < 0.001).

CONCLUSIONS

LV dysfunction has an adverse impact on renal outcomes and mortality in patients with sepsis and seems to be independent of fluid balance. Additional therapeutic options to restore organ perfusion are needed for patients with sepsis who have LV dysfunction, in addition to intravenous fluid restriction.

Klotho/FGF23 and Wnt Signaling as Important Players in the Comorbidities Associated with Chronic Kidney Disease

Fibroblast Growth Factor 23 (FGF23) and Klotho play an essential role in the regulation of mineral metabolism, and both are altered as a consequence of renal failure. FGF23 increases to augment phosphaturia, which prevents phosphate accumulation at the early stages of chronic kidney disease (CKD). This effect of FGF23 requires the presence of Klotho in the renal tubules. However, Klotho expression is reduced as soon as renal function is starting to fail to generate a state of FGF23 resistance. Changes in these proteins directly affect to other mineral metabolism parameters; they may affect renal function and can produce damage in other organs such as bone, heart, or vessels. Some of the mechanisms responsible for the changes in FGF23 and Klotho levels are related to modifications in the Wnt signaling. This review examines the link between FGF23/Klotho and Wnt/β-catenin in different organs: kidney, heart, and bone. Activation of the canonical Wnt signaling produces changes in FGF23 and Klotho and vice versa; therefore, this pathway emerges as a potential therapeutic target that may help to prevent CKD-associated complications.

Right Heart Failure and Cardiorenal Syndrome

Cardiorenal syndrome is a complex interplay of dysregulated heart and kidney interaction that leads to multiorgan system dysfunction, which is not an uncommon occurrence in the setting of right heart failure. The traditional concept of impaired perfusion and forward flow recently has been modified to include the recognition of systemic venous congestion as a contributor, with direct and indirect mechanisms, including elevated renal venous pressure, reduced renal perfusion pressure, increased renal interstitial pressure, tubular dysfunction, splanchnic congestion, and neurohormonal and inflammatory activation. Treatment options beyond diuretics and vasoactive drugs remain limited and lack supportive evidence.

Central venous pressure and the risk of diuretic-associated acute kidney injury in patients after cardiac surgery

BACKGROUND

When prescribing diuretics in the postcardiac surgical intensive care unit (ICU), clinicians may use central venous pressure (CVP) to assess volume status and the risk of acute kidney injury (AKI). In this study, we examined how the risk of diuretic-associated AKI varied with CVP in patients undergoing cardiac surgery.

METHODS

We used the Medical Information Mart for Intensive Care database to study adults admitted to the postcardiac surgical ICU at an urban, academic medical center between 2001 and 2012. We examined the odds of AKI per 1-mm Hg increase in CVP among patients receiving intravenous loop diuretics using multivariable adjusted logistic regression. We examined the risk of AKI among patients with diuretic use (vs nonuse) across tertiles of CVP using inverse probability treatment weighting.

RESULTS

Among 4,164 patients receiving intravenous loop diuretics, the adjusted odds of subsequent AKI were 1.11 (95% CI 1.08-1.13) times higher per mm Hg increase in mean CVP. This association was log-linear across the entire range of CVPs observed. In the analysis of diuretic use (n = 5,396), the adjusted risk ratio for AKI with diuretic use (vs nonuse) was 1.33 (95% CI 1.21-1.47) and did not materially differ across tertile of CVP.

CONCLUSIONS

Higher rather than lower CVP is an independent marker of AKI risk. The risk of AKI associated with diuretic use may not be influenced by CVP. Novel methods of assessing volume status and AKI risk are needed to guide patient selection for diuretic therapy.

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Cardiorenal Syndrome: Classification, Pathophysiology, Diagnosis, and Treatment Strategies: A Scientific Statement From the American Heart Association

Cardiorenal syndrome encompasses a spectrum of disorders involving both the heart and kidneys in which acute or chronic dysfunction in 1 organ may induce acute or chronic dysfunction in the other organ. It represents the confluence of heart-kidney interactions across several interfaces. These include the hemodynamic cross-talk between the failing heart and the response of the kidneys and vice versa, as well as alterations in neurohormonal markers and inflammatory molecular signatures characteristic of its clinical phenotypes. The mission of this scientific statement is to describe the epidemiology and pathogenesis of cardiorenal syndrome in the context of the continuously evolving nature of its clinicopathological description over the past decade. It also describes diagnostic and therapeutic strategies applicable to cardiorenal syndrome, summarizes cardiac-kidney interactions in special populations such as patients with diabetes mellitus and kidney transplant recipients, and emphasizes the role of palliative care in patients with cardiorenal syndrome. Finally, it outlines the need for a cardiorenal education track that will guide future cardiorenal trials and integrate the clinical and research needs of this important field in the future.

MELD-XI Score and Coronary Artery Disease Prevalence and Extent Among In-Hospital Patients With End-Stage Liver Failure Awaiting Transplant

OBJECTIVES

Liver transplant is a life-saving procedure for a variety of end-stage liver diseases. Cardiovascular disorders are among the leading cause of death among patients with end-stage liver disease and those undergoing liver transplant procedures. MELD-XI score is a newly developed score for mortality prediction in patients with end-stage liver failure. In this study, we investigated the relationships among MELD-XI score, total in-hospital mortality, and coronary artery disease severity and extent among patients with end-stage liver failure who were awaiting transplant.

MATERIALS AND METHODS

We retrospectively reviewed medical records of 121 patients with end-stage liver failure on transplant wait list. Study patients had undergone coronary angiography as part of pretransplant cardiac evaluation. We determined prevalence of coronary artery disease and Gensini score (which indicates extent of coronary artery disease) using coronary angiography and reviewed MELD-XI score and in-hospital mortality rates. We compared MELD-XI score and Gensini score in deceased and surviving patients and correlated both scores with mortality and with each other.

RESULTS

Of 121 patients, 79 (65.3%) were men; mean age of the study population was 59.6 ± 10.2 years. Twenty-eight patients (23.1%) had coronary artery disease, and 13 (10.7%) had severe coronary artery disease on coronary angiography. Twenty-three patients (19%) died while on the transplant wait list. Gensini score and MELD-XI scores were significantly higher in those who died (P < .05). MELD-XI score, but not Gensini score, was a significant independent predictor of death among patients awaiting liver transplant (hazard ratio = 1.35; 95% confidence interval, 1.04-1.78; P < .05).

CONCLUSIONS

MELD-XI score independently predicted in-hospital death among patients scheduled to undergo liver transplant. These patients also had increased prevalence and extent of coronary artery disease.