Haemostasis in chronic kidney disease

Clinical outcomes of prolonged dual antiplatelet therapy after coronary drug-eluting stent implantation in dialysis patients

Background

End-stage renal disease yields susceptibility to both ischemia and bleeding. The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is not established in dialysis patients, who are usually excluded from randomized studies. Since recent studies implied the benefits of prolonged DAPT >12 months in chronic kidney disease, we investigated the effectiveness and safety of prolonged DAPT in dialysis patients with higher cardiovascular risks.

Methods

In this nationwide population-based study, we analyzed dialysis patients who underwent DES implantation from 2008 to 2015. Continued DAPT was compared with discontinued DAPT using landmark analyses, including free-of-event participants at 12 (n = 2246), 15 (n = 1925) and 18 months (n = 1692) after DES implantation. The primary outcome was major adverse cardiovascular events (MACEs): a composite of mortality, nonfatal myocardial infarction, coronary revascularization and stroke. Major bleeding was a safety outcome. Inverse probability of treatment weighting Cox regression was performed.

Results

Mean follow-up periods were 278.3-292.4 days, depending on landmarks. Overall, incidences of major bleeding were far lower than those of MACE. Continued DAPT groups showed lower incidences of MACE and higher incidences of major bleeding, compared with discontinued DAPT groups. In Cox analyses, continued DAPT reduced the hazards of MACE at the 12- [hazard ratio (HR) = 0.74, 95% confidence interval (CI) 0.61-0.90; P = 0.003], 15- (HR = 0.78, 95% CI 0.64-0.96; P = 0.019) and 18-month landmarks (HR = 0.79, 95% CI 0.63-0.99; P = 0.041), but without a significant increase in major bleeding at 12 (HR = 1.39, 95% CI 0.90-2.16; P = 0.14), 15 (HR = 1.13, 95% CI 0.75-1.70; P = 0.55) or 18 months (HR = 1.27, 95% CI 0.83-1.95; P = 0.27).

Conclusions

Prolonged DAPT reduced MACE without significantly increasing major bleeding in patients who were event-free at 12 months after DES implantation. In deciding on DAPT duration, prolonged DAPT should be considered in dialysis patients.

Coagulation parameters are associated with the prognosis of immunoglobulin a nephropathy: a retrospective study

Background

Interstitial fibrosis/tubular atrophy (T) score is a known determinant of the progression of immunoglobulin A nephropathy (IgAN). Strong evidence indicates that the components of the coagulation system closely linked with fibrotic events have been highlighted in the kidney. However, whether the coagulation system can affect the renal outcome of IgAN remains unclear. Herein, we investigated the association of coagulation parameters and pathological phenotype of IgAN and their combined effects on the deterioration of renal function.

Methods

This retrospective study included N = 291 patients with biopsy-proven IgAN from May 2009 to April 2013 in the Second Xiangya Hospital. Clinical data, pathological features were collected, and the associations of coagulation parameters at biopsy, T score, and renal outcome were evaluated. T score indicated the degree of tubular atrophy or interstitial fibrosis. The renal outcome was defined as an end-stage renal disease (ESRD) or an irreversible 50% estimated glomerular filtration rate (eGFR) reduction.

Results

Shorter prothrombin time (PT) and the activated partial thromboplastin time (APTT) were significantly associated with T (both p < 0.001). PT (< 11.15 s) or APTT (< 29.65 s) had worse cumulative survival rate (p = 0.008, p = 0.027 respectively) and were significantly but not independently associated with a higher risk of renal outcome (p = 0.012, p = 0.032 respectively). In the combined analyses of PT, APTT, and T lesions, the odd ratios for the outcome were significantly higher in the presence of T with PT (< 11.15 s) or APTT (< 29.65 s).

Conclusion

Shorter PT and APTT are associated with an increased incidence of the T lesion and are additional factors that portend a poorer prognosis in IgAN. Monitoring coagulation function might be important when assessing the risk of progression. Additional studies exploring the molecular mechanism between coagulation and IgAN pathology are needed.

Genetic Polymorphisms and Perioperative Bleeding in Off-Pump Coronary Artery Bypass Grafting Surgery

BACKGROUND

Clopidogrel use before coronary artery bypass graft surgery may increase risk for perioperative hemorrhage. The effect of genetic polymorphisms related to clopidogrel responses on bleeding during or after off-pump coronary artery bypass graft surgery is unknown.

METHODS

This prospective study included 206 coronary artery disease patients scheduled for off-pump coronary artery bypass graft surgery. Genotypes were determined using Sequenom MassARRAY system. Severe bleeding was defined by the universal definition of perioperative bleeding in cardiac surgery.

RESULTS

Patients carrying the ABCB1 3435 wild-type genotype (CC) had a higher risk of severe perioperative bleeding compared with patients carrying the variant genotype (CT or TT; 33.9% vs 16.5%, P = .009). Low baseline hemoglobin level (odds ratio 0.944; 95% confidence interval, 0.917 to 0.972; P < .001), low baseline estimated glomerular filtration rate (odds ratio 0.977; 95% confidence interval, 0.956 to 0.999; P = .041), discontinuing clopidogrel 5 days or less before surgery (odds ratio 2.458; 95% confidence interval, 1.044 to 5.786; P = .039), and the ABCB1 wild-type genotype (CC; odds ratio 2.941; 95% confidence interval, 1.250 to 6.944; P = .014) were independent risk factors for severe perioperative bleeding.

CONCLUSIONS

Patients carrying the ABCB1 wild-type genotype (CC) had a higher rate of severe perioperative bleeding compared with patients carrying the variant genotype (CT or TT). Discontinuation of clopidogrel 5 days or less before surgery and the ABCB1 wild-type genotype (CC) were independent risk factors for severe perioperative bleeding.

Fibrinogen Modification and Fibrin Formation in Patients with an End-Stage Renal Disease Subjected to Peritoneal Dialysis

End-stage renal disease (ESRD) is a condition accompanied by increased inflammation, oxidative stress, risk of cardiovascular complications, and coagulopathies. The structure of fibrinogen and characteristics of fibrin from plasma samples of ESRD patients on peritoneal dialysis (PD) was investigated. Fibrinogen from ESRD patients had a higher degree of carbonylation than fibrinogen from healthy individuals. The Aα chain was the most susceptible to oxidation, followed by the Bβ chain, whereas the γ-chain was the most resistant to oxidation. Spectrofluorimetric analysis suggested a higher extent of modification of amino acid side chains in fibrinogen from ESRD patients. The tertiary structure of fibrinogen was more affected than its secondary structure. The kinetics (time and rate) of fibrinogen coagulation did not differ between the tested groups. Fibrin prepared from the isolated fibrinogen had a similar structure in both groups. Our results confirm that oxidation and structural alterations of fibrinogen occur in ESRD patients on PD, although these modifications produce no direct effect on the fibrin formation. Taking into account that some patients suffer from bleeding, whereas others develop thrombotic complications, further research on this subject is required to identify other components and processes that contribute to the outcome.

Graft Function, Albuminuria, and the Risk of Hemorrhage and Thrombosis After Kidney Transplantation

Background:

Compared to the general population, kidney transplant recipients are at increased risk of hemorrhage and thrombosis. Whether this risk is affected by graft function and albuminuria is unknown.

Objective:

To determine the association between graft function and albuminuria and the risk of post-transplant hemorrhage and thrombosis.

Design:

Retrospective cohort study.

Setting:

We used linked health care databases in Alberta, Canada.

Patients/sample/participants:

We included adult kidney transplant recipients from 2002 to 2015 with a functioning graft at 1 year.

Measurements:

Estimated glomerular filtration rate (eGFR) and albuminuria measurements at 1 year post-transplant were used to categorize recipients (eGFR: ≥45 vs. <45 mL/min/1.73 m²; albuminuria: absence vs. presence). We determined the rates of post-transplant hemorrhage and venous thrombosis based on validated diagnostic and procedural codes.

Methods:

We determined the association between categories of eGFR and albuminuria and post-transplant hemorrhage and venous thrombosis using Poisson regression with log link.

Results:

Of 1284 kidney transplant recipients, 21% had an eGFR <45 mL/min/1.73 m² and 40% had presence of albuminuria at 1 year post-transplant. Over a median follow-up of 6 years, there were 100 hemorrhages (12.6 events per 1000 person-years) and 57 venous thrombosis events (7.1 events per 1000 person-years). The age- and sex-adjusted rate of hemorrhage and thrombosis was over 2-fold higher in recipients with lower eGFR and presence of albuminuria compared to higher eGFR and no albuminuria (hemorrhage: incidence rate ratio, IRR, 2.6, 95% confidence interval [CI]: 1.5-4.4, P = .001; thrombosis: IRR, 2.3, 95% CI: 1.1-5.0, P = .046).

Limitations:

Complete relevant medication information, such as anticoagulants, were not available in our datasets. Due to sample size, this study was underpowered to conduct a fully adjusted analysis.

Conclusion:

Among kidney transplant recipients, lower eGFR and presence of albuminuria at 1 year post-transplant were associated with an over 2-fold higher risk of hemorrhage and venous thrombosis. Graft function and albuminuria at 1 year post-transplant are important prognostic factors in determining risk of post-transplant hemorrhage and venous thrombosis. Further research, including medication data, are needed to further delineate outcomes and safety.

Trial registration:

Not applicable (cohort study).

Assessment of Outcomes Among Patients With Venous Thromboembolism With and Without Chronic Kidney Disease

IMPORTANCE

Patients with venous thromboembolism (VTE) and concomitant chronic kidney disease (CKD) have been reported to have a higher risk of thrombosis and major bleeding complications compared with patients without concomitant CKD. The use of anticoagulation therapy is challenging, as many anticoagulant medications are excreted by the kidney. Large-scale data are needed to clarify the impact of CKD for anticoagulant treatment strategies and clinical outcomes of patients with VTE.

OBJECTIVE

To compare clinical characteristics, treatment patterns, and 12-month outcomes among patients with VTE and concomitant moderate to severe CKD (stages 3-5) vs patients with VTE and mild to no CKD (stages 1-2) in a contemporary international registry.

DESIGN, SETTING, AND PARTICIPANTS

The Global Anticoagulant Registry in the Field-Venous Thromboembolism (GARFIELD-VTE) study is a prospective noninterventional investigation of real-world treatment practices. A total of 10 684 patients from 415 sites in 28 countries were enrolled in the GARFIELD-VTE between May 2014 and January 2017. This cohort study included 8979 patients (6924 patients with mild to no CKD and 2055 patients with moderate to severe CKD) who had objectively confirmed VTE within 30 days before entry in the registry. Chronic kidney disease stages were defined by estimated glomerular filtration rates. Data were extracted from the study database on December 8, 2018, and analyzed between May 1, 2019, and July 30, 2020.

EXPOSURE

Moderate to severe CKD vs mild to no CKD.

MAIN OUTCOMES AND MEASURES

The primary outcomes were all-cause mortality, recurrent VTE, and major bleeding. Event rates and 95% CIs were calculated and expressed per 100 person-years. Hazard ratios (HRs) were estimated with Cox proportional hazards regression models and adjusted for relevant confounding variables. All-cause mortality was considered a competing risk for other clinical outcomes in the estimation of cumulative incidences.

RESULTS

Of the 10 684 patients with objectively confirmed VTE, serum creatinine data were available for 8979 patients (84.0%). Of those, 4432 patients (49.4%) were female and 5912 patients (65.8%) were White; 6924 patients (77.1%; median age, 57 years; interquartile range [IQR], 44-69 years) were classified as having mild to no CKD, and 2055 patients (22.9%; median age, 70 years; IQR, 59-78 years) were classified as having moderate to severe CKD. Calculations using the equation from the Modification of Diet in Renal Disease study indicated that, among the 6924 patients with mild to no CKD, 2991 patients had stage 1 CKD, and 3933 patients had stage 2 CKD; among the 2055 patients with moderate to severe CKD, 1650 patients had stage 3 CKD, 190 patients had stage 4 CKD, and 215 patients had stage 5 CKD. The distribution of VTE presentation was comparable between groups. In total, 1171 patients (57.0%) with moderate to severe CKD and 4079 patients (58.9%) with mild to no CKD presented with deep vein thrombosis alone, 547 patients (26.6%) with moderate to severe CKD and 1723 patients (24.9%) with mild to no CKD presented with pulmonary embolism alone, and 337 patients (16.4%) with moderate to severe CKD and 1122 patients (16.2%) with mild to no CKD presented with both pulmonary embolism and deep vein thrombosis. Compared with patients with mild to no CKD, patients with moderate to severe CKD were more likely to be female (3259 women [47.1%] vs 1173 women [57.1%]) and older than 65 years (2313 patients [33.4%] vs 1278 patients [62.2%]). At baseline, the receipt of parenteral therapy alone was comparable between the 2 groups (355 patients [17.3%] with moderate to severe CKD vs 1253 patients [18.1%] with mild to no CKD). Patients with moderate to severe CKD compared with those with mild to no CKD were less likely to be receiving direct oral anticoagulant therapy, either alone (557 patients [27.1%] vs 2139 patients [30.9%]) or in combination with parenteral therapy (319 patients [15.5%] vs 1239 patients [17.9%]). Patients with moderate to severe CKD had a higher risk of all-cause mortality (adjusted hazard ratio [aHR], 1.44; 95% CI, 1.21-1.73), major bleeding (aHR, 1.40; 95% CI, 1.03-1.90), and recurrent VTE (aHR, 1.40; 95% CI, 1.10-1.77) than patients with mild to no CKD.

CONCLUSIONS AND RELEVANCE

In this study of patients with VTE, the presence of moderate to severe CKD was associated with increases in the risk of death, VTE recurrence, and major bleeding compared with the presence of mild to no CKD.

Pathophysiology of atrial fibrillation and chronic kidney disease

Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related conditions with shared risk factors. The growing prevalence of both AF and CKD indicates that more patients will suffer from concurrent conditions. There are various complex interlinking mechanisms with important implications for the management of these patients. Furthermore, there is uncertainty regarding the use of oral anticoagulation (OAC) in AF and CKD that is reflected by a lack of consensus between international guidelines. Therefore, the importance of understanding the implications of co-existing AF and CKD should not be underestimated. In this review, we discuss the pathophysiology and association between AF and CKD, including the underlying mechanisms, risk of thrombo-embolic and bleeding complications, influence on stroke management, and evidence surrounding the use of OAC for stroke prevention.

Anticoagulation in Patients with End-Stage Renal Disease and Atrial Fibrillation: Confusion, Concerns and Consequences

End-stage renal disease (ESRD) patients have a higher prevalence of diabetes mellitus, hypertension, congestive heart failure and advanced age, along with an increased incidence of non-valvular atrial fibrillation (AF), thereby increasing the risk for cerebrovascular accidents. Systemic anticoagulation is therefore recommended in patients with ESRD with AF to reduce the risk and complications from thromboembolism. Paradoxically, these patients are at an increased risk of bleeding due to great degree of platelet dysfunction and impaired interaction between platelet and endothelium. Currently, CHA2DS2-VASc and Hypertension, Abnormal liver/kidney function, Stroke, Bleeding, Labile INR, Elderly, Drugs or alcohol (HAS-BLED) are the recommended models for stroke risk stratification and bleeding risk assessment in patients with AF. There is conflicting data regarding benefits and risks of medications such as antiplatelet agents, warfarin and direct oral anticoagulants in ESRD patients with AF. Moreover, there is no randomized controlled trial data to guide the clinical decision making. Hence, a multi-disciplinary approach with annual re-evaluation of treatment goals and risk-benefit assessment has been recommended. In this article, we review the current recommendations with risks and benefits of anticoagulation in patients with ESRD with AF.

Plasma fibrinogen and mortality in patients undergoing peritoneal dialysis: a prospective cohort study

BACKGROUND

Plasma fibrinogen is significantly associated with cardiovascular (CV) events and mortality in the general population. However, the association between plasma fibrinogen and mortality in patients undergoing peritoneal dialysis (PD) is unclear.

METHODS

This was a prospective cohort study. A total of 1603 incident PD patients from a single center in South China were followed for a median of 46.7 months. A Cox regression analysis was used to evaluate the independent association of plasma fibrinogen with CV and all-cause mortality. Models were adjusted for age, sex, smoking, a history of CV events, diabetes, body mass index, systolic blood pressure, hemoglobin, blood platelet count, serum potassium, serum albumin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, hypersensitive C-reactive protein, estimated glomerular filtration rate, antiplatelet agents and lipid-lowering drugs.

RESULTS

The mean age was 47.4 ± 15.3 years, 955 (59.6%) patients were male, 319 (19.9%) had a history of CV events, and 410 (25.6%) had diabetes. The average plasma fibrinogen level was 4.12 ± 1.38 g/L. Of the 474 (29.6%) patients who died during follow-up, 235 (49.6%) died due to CV events. In multivariable models, the adjusted hazard ratios (HRs) for quartile 1, quartile 3, and quartile 4 versus quartile 2 were 1.18 (95% confidence interval [CI], 0.72-1.95, P = 0.51), 1.47 (95% CI, 0.93-2.33, P = 0.10), and 1.78 (95% CI, 1.15-2.77, P = 0.01) for CV mortality and 1.20 (95% CI, 0.86-1.68, P = 0.28), 1.29 (95% CI, 0.93-1.78, P = 0.13), and 1.53 (95% CI, 1.12-2.09, P = 0.007) for all-cause mortality, respectively. A nonlinear relationship between plasma fibrinogen and CV and all-cause mortality was observed.

CONCLUSIONS

An elevated plasma fibrinogen level was significantly associated with an increased risk of CV and all-cause mortality in patients undergoing PD.

Prevention and Treatment of Bleeding with Direct Oral Anticoagulants

Anticoagulant-related bleeding carries considerable morbidity and mortality. Major or life-threatening bleeding is among the most severe of these complications. As the number of patients treated with direct oral anticoagulants (DOACs) continues to increase, so does the number of DOAC-related bleeding events. The incidence of CRNM bleeding related to DOAC therapy ranges from 15 to 18% per 100-year patients, while the incidence of major bleeding ranges from 2.71 to 3.6%. Many of these bleeding events can be prevented with tailored dosing regimens or proper peri-procedural management. When unable to be prevented, DOAC-related bleeding can lead to significant long-term disability or death. Management with newer reversal agents such as andexanet alfa and idarucizumab, as well as prothrombin complex concentrates, may improve outcomes for patients with DOAC-related bleeding. The purpose of this review is to explore strategies for preventing and treating bleeding in patients receiving DOACs for anticoagulant therapy.

Predictiveness of different preoperative risk assessments for postoperative bleeding after coronary artery bypass grafting surgery

Aim:

Postoperative bleeding is a significant cause of morbidity and mortality in patients undergoing cardiac surgery. Studies have been conducted, and guidelines have been published regarding patient blood management and aiming to prevent blood loss in the perioperative period. Various bleeding risk assessments were developed for preoperative period. We aimed to examine the correlations of scoring systems in the literature with the amount of postoperative bleeding in patients undergoing first time coronary artery bypass graft surgery, and to show the most suitable preoperative bleeding risk assessment for coronary artery bypass graft patients.

Methods:

The study included 550 consecutive patients who underwent coronary artery bypass graft operation. The inclusion criteria were considered as patients to be older than 18 years old and to undergo elective or emergent myocardial revascularization using cardiopulmonary bypass. All variables required for scoring systems were recorded. The initial results of the study were determined as the amount of chest tube drainage, the use of blood products, the change in hematocrit level, reoperation due to bleeding, duration of ventilation, duration of intensive care unit stay, and hospital stay. Mortality which occurred during first 30 days after operation was considered as operative mortality. Operative mortality was accepted as the primary endpoint. Secondary endpoints were massive bleeding and high amount of transfusion.

Results:

Data were obtained from a series of 550 consecutive patients treated with isolated coronary artery bypass graft. It was seen that PAPWORTH and WILL-BLEED risk assessments responded better for E-CABG grade 2 and 3 bleeding compared to other risk assessments. TRACK, TRUST, and ACTA-PORT scales were found to have low ability to distinguish patients with E-CABG bleeding grade 2 and 3.

Conclusion:

Predicting postoperative bleeding and transfusion rates with preoperative risk scores in patients undergoing coronary artery bypass graft surgery will provide valuable information to physicians for establishing a proper patient blood management protocol and this will decrease excessive transfusions, unnecessary reoperations as well as improve postoperative outcomes.

Apixaban Downregulates Endothelial Inflammatory and Prothrombotic Phenotype in an In Vitro Model of Endothelial Dysfunction in Uremia

PURPOSE

Chronic kidney disease (CKD) associates with inflammatory and prothrombotic phenotypes, resulting in higher cardiovascular risk. Factor Xa displays functions beyond coagulation, exhibiting proinflammatory effects. The aim of the present study was to investigate whether a direct FXa inhibitor protects from the endothelial dysfunction (ED) caused by uremia.

METHODS

Macro (HUVEC) and microvascular (HMEC) endothelial cells (ECs) were exposed to serum from uremic patients or healthy donors, in absence and presence of apixaban (60 ng/ml). We evaluated changes in surface VCAM-1 and ICAM-1, intracellular eNOS, reactive oxygen species (ROS), and von Willebrand Factor (VWF) production by immunofluorescence, reactivity of the extracellular matrix (ECM) towards platelets, and intracellular signaling.

RESULTS

ECs exposed to uremic serum triggered dysregulation of all the parameters. Presence of apixaban resulted in decreased expression of VCAM-1 (178 ± 14 to 89 ± 2% on HMEC and 324 ± 71 to 142 ± 25% on HUVEC) and ICAM-1 (388 ± 60 to 111 ± 10% on HMEC and 148 ± 9% to 90 ± 7% on HUVEC); increased eNOS (72 ± 8% to 95 ± 10% on HMEC); normalization of ROS levels (173 ± 21 to 114 ± 13% on HMEC and 165 ± 14 to 127 ± 7% on HUVEC); lower production of VWF (168 ± 14 to 92 ± 4% on HMEC and 151 ± 22 to 99 ± 11% on HUVEC); and decreased platelet adhesion onto ECM (134 ± 22 to 93 ± 23% on HMEC and 161 ± 14 to 117 ± 7% on HUVEC). Apixaban inhibited p38MAPK and p42/44 activation in HUVEC (139 ± 15 to 48 ± 15% and 411 ± 66 to 177 ± 57%, respectively) (p < 0.05 vs control for all parameters).

CONCLUSION

Anti-FXa strategies, such as apixaban, prevented ED caused by the uremic milieu, exhibiting anti-inflammatory and antioxidant properties and modulating the reactivity of the ECM.

Small bowel angioectasia as a marker of frailty and poor prognosis

Background and study aims  This study aimed to establish 5-year survival of patients diagnosed with bleeding small bowel (SB) angioectasia, with the hypothesis that many will suffer deaths relating to comorbidity rather than gastrointestinaI bleeding. Patients and methods  SB capsule endoscopy (SBCE) procedures, performed for suspected SB bleeding or iron deficiency anemia, with angioectasia isolated as the cause of SB bleeding and at least 5 years of follow-up data were isolated (n = 125) along with an age-matched group with "normal" SBCE procedures (n = 125). These were retrospectively analysed with further information on mortality and comorbidity gathered through hospital records. Results  Those with angioectasia had a median age of 72.7 years and comorbidities were common. The 5-year survival was 64.0 % (80/125) compared to 70.4 % (88/125) in those with "normal" SBCE. Those with significant cardiac or vascular comorbidity had a poorer survival (52.9 % (37/70) at 5 years) but anticoagulation/antiplatelets/ number of lesions or requirement endoscopic treatment seemed to make little difference. In those with SB bleeding secondary to angioectasia none of the subsequent deaths were directly attributable to gastrointestinal bleeding. Conclusions  In this cohort, SB angioectasia did not lead to any deaths but the 5-year survival was poor due to those diagnosed often being older and having comorbidities. This would support the hypothesis that a diagnosis of SB bleeding secondary to angioectasia suggests frailty.

Cerebrovascular Disease and Cognition in Chronic Kidney Disease Patients

Chronic kidney disease (CKD) affects both brain structure and function. Patients with CKD have a higher risk of both ischemic and hemorrhagic strokes. Age, prior disease history, hypertension, diabetes, atrial fibrillation, smoking, diet, obesity, and sedimentary lifestyle are most common risk factors. Renal-specific pathophysiologic derangements, such as oxidative stress, chronic inflammation, endothelial dysfunction, vascular calcification, anemia, gut dysbiosis, and uremic toxins are important mediators. Dialysis initiation constitutes the highest stroke risk period. CKD significantly worsens stroke outcomes. It is essential to understand the risks and benefits of established stroke therapeutics in patients with CKD, especially in those on dialysis. Subclinical cerebrovascular disease, such as of silent brain infarction, white matter lesions, cerebral microbleeds, and cerebral atrophy are more prevalent with declining renal function. This may lead to functional brain damage manifesting as cognitive impairment. Cognitive dysfunction has been linked to poor compliance with medications, and is associated with greater morbidity and mortality. Thus, understanding the interaction between renal impairment and brain is important in to minimize the risk of neurologic injury in patients with CKD. This article reviews the link between chronic kidney disease and brain abnormalities associated with CKD in detail.

How do Uremic Toxins Affect the Endothelium?

Uremic toxins can induce endothelial dysfunction in patients with chronic kidney disease (CKD). Indeed, the structure of the endothelial monolayer is damaged in CKD, and studies have shown that the uremic toxins contribute to the loss of cell–cell junctions, increasing permeability. Membrane proteins, such as transporters and receptors, can mediate the interaction between uremic toxins and endothelial cells. In these cells, uremic toxins induce oxidative stress and activation of signaling pathways, including the aryl hydrocarbon receptor (AhR), nuclear factor kappa B (NF-κB), and mitogen-activated protein kinase (MAPK) pathways. The activation of these pathways leads to overexpression of proinflammatory (e.g., monocyte chemoattractant protein-1, E-selectin) and prothrombotic (e.g., tissue factor) proteins. Uremic toxins also induce the formation of endothelial microparticles (EMPs), which can lead to the activation and dysfunction of other cells, and modulate the expression of microRNAs that have an important role in the regulation of cellular processes. The resulting endothelial dysfunction contributes to the pathogenesis of cardiovascular diseases, such as atherosclerosis and thrombotic events. Therefore, uremic toxins as well as the pathways they modulated may be potential targets for therapies in order to improve treatment for patients with CKD.

Tissue Factor and Risk of Complications After Kidney Transplantation

OBJECTIVE

Tissue factor (TF) is a membrane component of many cells and a strong activator of blood coagulation. Damage to the cells induces an increase in its expression and concentration in blood plasma. The injury and breakdown of the cells is inseparably connected with the harvesting and preservation of the kidney.

PURPOSE

The aim of the study was an analysis of TF in the renal vein after of restoration of circulation in the transplanted kidney. An additional goal was to investigate the impact of warm ischemia on TF.

MATERIALS AND METHODS

The examined group included 61 kidney recipients. Blood was taken from the renal vein in the first minute during reperfusion. Simultaneously, blood from a peripheral vein was also drawn. Apart from tissue factor (TF), I also examined thrombin/antithrombin complexes and fragments 1+2 of prothrombin.

RESULTS

In blood from renal veins, I noticed higher level of TF, thrombin/antithrombin complexes and fragments 1+2 of prothrombin in comparison with blood from peripheral veins (P < .0048, P < .016, P < .046, respectively). The 29 recipients (47% of the total) with postoperative complications had much higher concentrations of TF than others (P < .019). TF showed a strong positive correlation with the time of warm ischemia (r = 0.53864, P < .05).

CONCLUSIONS

The donor kidney appeared to be one of the main sources of TF in the blood of recipients. Warm ischemia significantly increased its concentration in renal vein blood. This concentration of TF may be associated with damage to the kidney. TF significantly increased the risk of postoperative complications.

Health risk of travel for chronic kidney disease patients

The number of people with chronic kidney disease (CKD) has increased and so has their demand for travel. However, the health risk posed by travel in these patients is unclear. Few reports document the travel risk in CKD and dialysis patients. The aim of this study is to summarize the existing evidence of the influence of travel on risks in CKD patients. We aim to describe the association between the impact of travel risks and patients with CKD. A detailed review of recent literature was performed by reviewing PubMed, Google Scholar, and Ichushi Web from the Japan Medical Abstracts Society. Screened involved the following keywords: “traveler's thrombosis,” “venous thromboembolism,” “deep vein thrombosis,” “altitude sickness,” “traveler's diarrhea,” “jet lag syndrome,” “melatonin,” with “chronic kidney disease” only, or/and “dialysis.” We present a narrative review summary of the literature from these screenings. The increased prevalence of thrombosis among travelers with CKD is related to a decrease in the estimated glomerular filtration rate and an increase in urine protein levels. CKD patients who remain at high altitudes are at an increased risk for progression of CKD, altitude sickness, and pulmonary edema. Traveler's diarrhea can become increasingly serious in patients with CKD because of decreased immunity. Microbial substitution colitis is also common in CKD patients. Moreover, time differences and disturbances in the circadian rhythm increase cardiovascular disease events for CKD patients. The existing literature shows that travel-related conditions pose an increased risk for patients with CKD.

[Thromboelastography-based assessment of coagulation function in patients with chronic kidney disease and the risk factors of hypercoagulability]

OBJECTIVE

To assess the changes in the coagulation profiles of patients with chronic kidney disease (CKD) using thromboelastography (TEG) and identify the risk factors of hypercoagulation in CKD patients.

METHODS

A total of 128 patients with CKD admitted in Hunan Provincial People's Hospital between August, 2018 and May, 2019 were recruited. The results of conventional coagulation test and TEG were compared between patients with CKD and 21 healthy control adults. The patients with CKD were divided into hypercoagulation group with a maximum amplitude (MA) &gt; 68 mm (n=66) and non-hypercoagulation group (MA≤68 mm, n=62). The laboratory indicators were compared between the groups, and the factors affecting the hypercoagulable state in patients with CKD were analyzed.

RESULTS

The levels of fibrinogen and D-Dimer increased significantly in patients with CKD at different stages as compared with the control subjects (P &lt; 0.05). In the patients with CKD, the reaction time and K time decreased while MA, α-angle and coagulation index increased significantly in patients in stage 3-4 and those in stage 5 either with or without hemodialysis compared with the control group (P &lt; 0.05). The estimated glomerular filtration rate (eGFR), percentage of patients with diabetes mellitus, history of stroke, percentage of neutrophils, neutrophil-lymphocyte ratio, red blood cell count, hemoglobin levels, platelet count, serum creatinine, serum cystatin-C, serum albumin, and lipoprotein (a) all differed significantly between hypercoagulation group and non-hypercoagulation group (P &lt; 0.05). The eGFR, platelet count and hemoglobin levels were identified as independent factors affecting hypercoagulability in patients with CKD (P &lt; 0.05).

CONCLUSIONS

s The hypercoagulable state of patients with CKD worsens gradually with the disease progression, and eGFR, platelet count and hemoglobin levels are all risk factors for the hypercoagulable state in patients with CKD.

Assessment of Thrombotic and Bleeding Tendency in Two Mouse Models of Chronic Kidney Disease: Adenine-Diet and 5/6th Nephrectomy

The coexistence of bleeding and thrombosis in patients with chronic kidney disease (CKD) is frequent and poorly understood. Mouse models are essential to understand complications of CKD and to develop new therapeutic approaches improving the health of patients. We evaluated the hemostasis in two models of renal insufficiency: adenine-diet and 5/6th nephrectomy (5/6Nx). Compared with 5/6Nx mice, mice fed with 0.25% adenine had more severe renal insufficiency and so higher levels of prothrombotic uremic toxins like indoxyl sulfate. More severe renal inflammation and fibrosis were observed in the adenine group, as demonstrated by histological and reverse transcription quantitative polymerase chain reaction experiments. Liver fibrinogen γ chain expression and level of plasma fibrinogen were increased only in adenine mice. In both CKD mouse models, tissue factor (TF) expression was increased in kidney and aorta extracts. Immunochemistry analysis of kidney sections showed that TF is localized in the vascular walls. Thrombin–antithrombin complexes were significantly increased in plasma from both adenine and 5/6Nx mice. Tail bleeding time increased significantly only in adenine mice, whereas platelet count was not significant altered. Finally, results obtained by intravital microscopy after laser-induced endothelial injury showed impaired platelet function in adenine mice and an increase in fibrin generation in 5/6Nx mice. To summarize, adenine diet causes a more severe renal insufficiency compared with 5/6Nx. The TF upregulation and the hypercoagulable state were observed in both CKD models. Bleeding tendency was observed only in the adenine model of CKD that recapitulates the whole spectrum of hemostasis abnormalities observed in advanced human CKD.

Indoxyl Sulfate, a Uremic Endotheliotoxin

Chronic kidney disease (CKD) is associated with a high prevalence of cardiovascular diseases. During CKD, the uremic toxin indoxyl sulfate (IS)—derived from tryptophan metabolism—accumulates. IS is involved in the pathophysiology of cardiovascular complications. IS can be described as an endotheliotoxin: IS induces endothelial dysfunction implicated in cardiovascular morbidity and mortality during CKD. In this review, we describe clinical and experimental evidence for IS endothelial toxicity and focus on the various molecular pathways implicated. In patients with CKD, plasma concentrations of IS correlate with cardiovascular events and mortality, with vascular calcification and atherosclerotic markers. Moreover, IS induces a prothrombotic state and impaired neovascularization. IS reduction by AST-120 reverse these abnormalities. In vitro, IS induces endothelial aryl hydrocarbon receptor (AhR) activation and proinflammatory transcription factors as NF-κB or AP-1. IS has a prooxidant effect with reduction of nitric oxide (NO) bioavailability. Finally, IS alters endothelial cell and endothelial progenitor cell migration, regeneration and control vascular smooth muscle cells proliferation. Reducing IS endothelial toxicity appears to be necessary to improve cardiovascular health in CKD patients.

Nitinol stent-assisted maturation of the dysfunctional cannulation zone in the immature arteriovenous fistula

INTRODUCTION

The native arteriovenous fistula may remain immature despite adequate arterial inflow after formation. This may occur when the puncturable vein segment (cannulation zone) is too small to be reliably punctured, occluded or too deep under the skin for needle access. We performed stenting (stent-assisted maturation) of arteriovenous fistulas with an immature cannulation zone, allowing for a large subcutaneous channel which could then be immediately punctured for dialysis.

METHODS

We performed a retrospective review of 49 patients (mean age was 58.7 ± 16.09 (12-83) years, mean arteriovenous fistula age of 162.6 ± 27.28 days) with end-stage renal failure who underwent balloon dilatation and bare-metal stent implantation (1.6 ± 0.67 (1-3) stents, median diameter and length of 8 (5-14) mm and 80 (40-150) mm, respectively) through their cannulation zone (forced maturation). Radiocephalic (35 arteriovenous fistulas), brachiocephalic (10 arteriovenous fistulas) and autogenous loop arteriovenous fistulas (4 arteriovenous fistulas) were included with 30 patients (61.2%) having an inadequate cannulation zone venous diameter, 9 patients (18.4%) having an absent cannulation zone and 10 patients (20.4%) having a patent cannulation zone deeper than 1 cm which was not reliably puncturable. The study was conducted over 9 years (January 2008-December 2016) with implantation of the SMART^® stent and Absolute Pro^® stent in 61.2% and 38.8%, respectively. Long-term outcomes including primary useable segmental and access circuit patency as well as assisted primary access circuit patency, rate of re-intervention, technical success and complications were analysed.

RESULTS

At 6 months, 12 months and 4 years, respectively, cannulation zone primary patency was 84.4%, 74.4% and 56.1% and access circuit primary patency was 62.2%, 45.3% and 23.2%; however, assisted primary access circuit patency was 95.6%, 91.1% and 83.8%, achieved with an endovascular re-intervention rate of 0.53 procedures/year with only four thrombosed circuits occurring.

DISCUSSION

Forced maturation using nitinol stents allows for long-term haemodialysis access with a low rate of re-intervention.

Anticoagulant strategies for the patient with chronic kidney disease

Chronic kidney disease (CKD) is a global health problem affecting up to 14% of the adult population in developed countries. On the basis of current guidelines, patients with CKD will often fulfil criteria for both short-term and long-term anticoagulation. Paradoxically, patients with CKD are not only at a higher risk of thrombosis, they are also at increased risk of bleeding. Furthermore, the pharmacokinetics and pharmacodynamics of many anticoagulant therapies are significantly affected by renal dysfunction. In addition, patients with advanced CKD are often systematically excluded from major clinical trials. As such, the decision on whether to anticoagulate or not, and if so with what agent, poses significant challenges. A solid understanding of the condition in question and the available treatments is required to make an informed judgement call. An in-depth appreciation of the advantages and disadvantages of the currently available anticoagulants is a key element in the decision-making process.

Outcomes After Transcatheter Mitral Valve Repair in Patients With Renal Disease

BACKGROUND

Renal disease is associated with poor prognosis despite guideline-directed cardiovascular therapy, and outcomes by sex in this population remain uncertain.

METHODS AND RESULTS

Patients (n=5213) who underwent a MitraClip procedure in the National Cardiovascular Data Registry Transcatheter Valve Therapy registry were evaluated for the primary composite outcome of all-cause mortality, stroke, and new requirement for dialysis by creatinine clearance (CrCl). Centers for Medicare and Medicaid Services-linked data were available in 63% of patients (n=3300). CrCl was <60 mL/min in 77% (n=4010) and <30 mL/min in 23% (n=1183) of the cohort. Rates of primary outcome were higher with lower CrCl (>60 mL/min, 1.4%; 30-<60 mL/min, 2.7%; <30 mL/min, 5.2%; dialysis, 7.8%; P<0.001), and all low CrCl groups were independently associated with the primary outcome (30-<60 mL/min: adjusted odds ratio, 2.32; 95% CI, 1.38-3.91; <30 mL/min: adjusted odds ratio, 4.44; 95% CI, 2.63-7.49; dialysis: adjusted hazards ratio, 4.52; 95% CI, 2.08-9.82) when compared with CrCl >60 mL/min. Rates of 1-year mortality were higher with lower CrCl (>60 mL/min, 13.2%; 30-<60 mL/min, 18.8%; <30 mL/min, 29.9%; dialysis, 32.3%; P<0.001), and all low CrCl groups were independently associated with 1-year mortality (30-<60 mL/min: adjusted hazards ratio, 1.50; 95% CI, 1.13-1.99; <30 mL/min: adjusted hazards ratio, 2.38; 95% CI, 1.78-3.20; adjusted hazards ratio: dialysis, 2.44; 95% CI, 1.66-3.57) when compared with CrCl >60 mL/min.

CONCLUSIONS

The majority of patients who undergo MitraClip have renal disease. Preprocedural renal disease is associated with poor outcomes, particularly in stage 4 or 5 renal disease where 1-year mortality is observed in nearly one-third. Studies to determine how to further optimize outcomes in this population are warranted.

Perioperative outcomes and risk assessment in dialysis patients: current knowledge and future directions

Perioperative medicine is rapidly emerging as a key discipline to address the specific needs of high-risk surgical groups, such as those on chronic dialysis. Crude hospital separation rates for chronic dialysis patients are considerably higher than patients with normal renal function, with up to 15% of admission being related to surgical intervention. Dialysis dependency carries substantial mortality and morbidity risk compared to patients with normal renal function. This group of patients has a high comorbid burden and complex medical need, making accurate perioperative planning essential. Existing perioperative risk assessment tools are unvalidated in chronic dialysis patients. Furthermore, they fail to incorporate important dialysis treatment-related characteristics that could potentially influence perioperative outcomes. There is a dearth of information on perioperative outcomes of Australasian dialysis patients. Current perioperative outcome estimates stem predominantly from North American literature; however, the generalisability of these findings is limited, as the survival of North American dialysis patients is significantly inferior to their Australasian counterparts and potentially confounds reported perioperative outcomes; let alone regional variation in surgical indication and technique. We propose that data linkage between high-quality national registries will provide more complete data with more detailed patient and procedural information to allow for more informative analyses to develop and validate dialysis-specific risk assessment tools.

Perioperative considerations for kidney and pancreas-kidney transplantation

Kidney transplantation is the treatment of choice in patients with end-stage renal disease, as it improves survival and quality of life. Living donor kidney transplant prior to pancreas transplantation, or simultaneous pancreas and kidney transplantation are discussed. Patients usually present comorbidities and extensive preoperative workups are recommended, especially cardiac assessment, though type and frequency of surveillance is not established. Nephroprotective strategies include adequate fluid status and goal-directed therapy. The conventional use of diuretics has not demonstrated a real nephroprotective effect at follow-up. Thromboprophylaxis regimes, especially for the pancreatic graft outcome, are of importance. Notably, transplantation in the obese population has increased in recent decades. Strict preoperative evaluation and pulmonary considerations must be kept in mind. Finally, robotic kidney transplant is a recent approach that presents anesthetic challenges, mainly related to steep Trendelenburg position and fluid restriction.

Renal dysfunction and long-term clinical outcomes in patients with venous thromboembolism: From the COMMAND VTE Registry

INTRODUCTION

Patients with renal dysfunction are at high risk for developing venous thromboembolism (VTE). However, the impact of renal dysfunction on recurrent VTE remains to be clarified. We assessed the relationship between estimated glomerular filtration rate (eGFR) at diagnosis and long-term clinical outcomes in VTE patients.

MATERIALS AND METHODS

The COMMAND VTE Registry is a multicenter registry enrolling consecutive patients with acute symptomatic VTE among 29 centers in Japan between January 2010 and August 2014. Patients with available creatinine values (N = 2829) were divided into the reference eGFR (≥60 mL/min/1.73 m²) group (N = 1760) and the low eGFR (<60 mL/min/1.73 m²) group (N = 1069). The low eGFR group was further subdivided into the moderately low eGFR (30-59 mL/min/1.73 m²) group (N = 898) and very low eGFR (<30 mL/min/1.73 m²) group (N = 171).

RESULTS

The low eGFR group was independently associated with the increased risk for recurrent VTE (adjusted HR 1.55, 95%CI 1.15-2.08). When the low eGFR group was subdivided into the moderately low and very low eGFR groups, the risk for recurrent VTE increased with decreasing eGFR (adjusted HR 1.43, 95%CI 1.04-1.95, and adjusted HR 2.54, 95%CI 1.42-4.28). The risk for major bleeding was higher in the very low eGFR group, but not in the moderately low eGFR group (adjusted HR 1.70, 95%CI 1.06-2.61, and adjusted HR 0.85, 95%CI 0.73-1.28).

CONCLUSIONS

Renal dysfunction measured by eGFR was associated with an increased risk for recurrent VTE, which was more prominent in severe renal dysfunction. Severe renal dysfunction was also associated with a higher risk for major bleeding.

Impact of renal function on clinical outcomes after PCI in ACS and stable CAD patients treated with ticagrelor: a prespecified analysis of the GLOBAL LEADERS randomized clinical trial

BACKGROUND

Impaired renal function (IRF) is associated with increased risks of both ischemic and bleeding events. Ticagrelor has been shown to provide greater absolute reduction in ischemic risk following acute coronary syndrome (ACS) in those with versus without IRF.

METHODS

A pre-specified sub-analysis of the randomized GLOBAL LEADERS trial (n = 15,991) comparing the experimental strategy of 23-month ticagrelor monotherapy (after 1-month ticagrelor and aspirin dual anti-platelet therapy [DAPT]) with 12-month DAPT followed by 12-month aspirin after percutaneous coronary intervention (PCI) in ACS and stable coronary artery disease (CAD) patients stratified according to IRF (glomerular filtration rate < 60 ml/min/1.73 m²).

RESULTS

At 2 years, patients with IRF (n = 2171) had a higher rate of the primary endpoint (all-cause mortality or centrally adjudicated, new Q-wave myocardial infarction [MI](hazard ratio [HR] 1.64, 95% confidence interval [CI] 1.35-1.98, p_adj = 0.001), all-cause death, site-reported MI, all revascularization and BARC 3 or 5 type bleeding, compared with patients without IRF. Among patients with IRF, there were similar rates of the primary endpoint (HR 0.82, 95% CI 0.61-1.11, p = 0.192, p_int = 0.680) and BARC 3 or 5 type bleeding (HR 1.10, 95% CI 0.71-1.71, p = 0.656, p_int = 0.506) in the experimental versus the reference group. No significant interactions were seen between IRF and treatment effect for any of the secondary outcome variables. Among ACS patients with IRF, there were no between-group differences in the rates of the primary endpoint or BARC 3 or 5 type bleeding; however, the rates of the patient-oriented composite endpoint (POCE) of all-cause death, any stroke, MI, or revascularization (p_int = 0.028) and net adverse clinical events (POCE and BARC 3 or 5 type bleeding) (p_int = 0.045), were lower in the experimental versus the reference group. No treatment effects were found in stable CAD patients categorized according to presence of IRF.

CONCLUSIONS

IRF negatively impacted long-term prognosis after PCI. There were no differential treatment effects found with regard to all-cause death or new Q-wave MI after PCI in patients with IRF treated with ticagrelor monotherapy.

CLINICAL TRIAL REGISTRATION

The trial has been registered with ClinicalTrials.gov, number NCT01813435.

Stent selection among patients with chronic kidney disease: Results from the NCDR CathPCI Registry

OBJECTIVES

This study sought to define contemporary rates of drug eluting stent (DES) usage in patients with chronic kidney disease (CKD).

BACKGROUND

Among patients with CKD undergoing percutaneous coronary interventions (PCIs), outcomes are superior for those who receive DES compared to those who receive bare metal stents (BMSs). However, perceived barriers may limit the use of DES in this population.

METHODS

All adult PCI cases from the NCDR CathPCI Registry involving coronary stent placement between July 1, 2009 and December 31, 2015 were analyzed. The rate of DES usage was then compared among four groups, stratified by CKD stage (I/II, III, IV, and V). Subgroup analysis was conducted based on PCI status and indication. Cases were linked to Medicare claims data to assess 1-year mortality.

RESULTS

A total of 3,650,333 PCI cases met criteria for analysis. DES usage significantly declined as renal function worsened (83.0%, 79.9%, 75.6%, and 75.6%, respectively, in the four CKD stages; p < .001). DES usage was universally lower across the four groups in the setting of ST-Elevation Myocardial Infarction (STEMI) (70.6%, 66.5%, 58.7%, 58.0%; p < .001) and higher in the setting of elective PCI (87.6%, 84.9%, 82.3%, 77.9%; p < .0001). DES was associated with improved 1-year survival, and usage increased over time across each group.

CONCLUSIONS

DESs are underutilized in patients with advanced renal dysfunction. Although DES usage has increased over time, variation still exists between patients with normal renal function and those with CKD.

Percutaneous left atrial appendage closure, a safe alternative to anticoagulation for patients with nonvalvular atrial fibrillation and end-stage renal disease on hemodialysis: A single center experience

The evidence about the effectiveness and safety of oral anticoagulation in patients on hemodialysis is conflicting and scarce. Percutaneous left atrial appendage occlusion (LAAO) has demonstrated to be a valid alternative therapeutic option for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). The aim of this study is to present the outcomes of percutaneous LAAO in patients with end-stage renal disease (ESRD) on hemodialysis and NVAF in our center. We conducted a retrospective review of clinical records, demographics, LAAO procedure, complications, and outcomes of patients with NVAF and ESRD on hemodialysis who underwent a percutaneous LAAO in our center between January 2017 and January 2019. In the period of the study, eight patients with ESRD on hemodialysis underwent a percutaneous LAAO in our center. The overall mean age was 67.5 years (range 56-81; SD ± 7.2). All patients had permanent NVAF. The total mean dialysis duration was 8.49 years (range 0.83-14.8; SD ± 6.2). The mean CHA2DS2-VASc and HAS-BLED scores were high (4.75 [SD ± 1.16] and 4.62 [SD ± 0.91], respectively). All patients had history of a major hemorrhagic event (BARC Score ≥3). Most patients (n = 6) showed left ventricular hypertrophy, and the average LVEF was 54% (SD ± 6.5). All devices were implanted successfully. Postprocedural antithrombotic regimen prescribed was based on antiplatelet therapy. No deaths, cardioembolic events, or major bleeding (according to the BARC scale) were reported during a mean follow-up of 14.24 months (SD ± 9.44). Percutaneous LAAO could be of particular interest in patients with NVAF and CKD in hemodialysis. Further studies will be necessary to confirm this hypothesis.

Surgical osteoplasty and soft tissue excision as treatment for facial deformities in patients with renal osteodystrophy: three case reports

BACKGROUND

Renal osteodystrophy (ROD) may occur in patients presenting chronic kidney disease (CKD), leading to laboratory test alterations and changes in bone turnover with extra-skeletal calcifications. Treatment involves the medical management of secondary hyperparathyroidism, potential total parathyroidectomy, and surgical interventions concerning calcifications if causing facial deformities with esthetic and functional repercussions. In this context, the aim of the present study is to describe three cases of facial deformities caused by ROD treated through cosmetic-functional surgeries.

CASE PRESENTATION

All patients underwent osteoplasty and soft tissue excision for several purposes, including speech difficulties, chewing difficulties, airway obstructions, malocclusion, and facial disharmony. Most patients were male (n = 2, 66.7%) with a mean age of 30.0 years old. Patients underwent a mean hemodialysis time of 9 years, and the maximum mean parathyroid hormone (PTH) level was of 2384.5 pg/ml.

CONCLUSIONS

Long hemodialysis periods and elevated PTH levels were the probable factors for the development of facial deformities in this group of patients. The main complications associated to the surgical management of facial deformities in ROD patients are directly related to end-stage renal disease, with increased risks for hemorrhage and systemic drug accumulation.

End stage renal disease modifies the effect of targeted temperature management after out-of-hospital cardiac arrest

INTRODUCTION

Kidney function can affect the permeability of the blood-brain barrier; thus, end-stage renal disease (ESRD) may alter the effects of targeted temperature management (TTM) on the neurological outcomes of out-of-hospital cardiac arrest (OHCA) patients. We aimed to investigate whether the interaction effect of TTM on outcomes after OHCA was observed among patients with and without ESRD.

METHODS

Adult OHCA patients with presumed cardiac etiology who attained sustained return of spontaneous circulation from 2013 to 2017 were included using nationwide OHCA registry. The main exposure variable was TTM. The primary endpoint was survival with good neurological recovery. Multivariable logistic regression analysis was performed after adjustment for potential confounders. To compare the effect of ESRD on TTM, an interaction term (TTM × ESRD) was added to the model.

RESULTS

A total of 21,250 patients were included in the analysis; 2693 (12.7%) patients underwent TTM. ESRD was observed in 128 (4.8%) in the TTM group and 767 (4.1%) in the no-TTM group. The TTM group showed better outcomes than the no-TTM group (32.4% vs. 17.2%, p < 0.01). The adjusted odds ratio of TTM for good neurological recovery in the entire study group was 1.15 (95% CI, 1.03-1.29). In the interaction model, the adjusted odds ratio of TTM for good neurological recovery was 0.47 (95% CI, 0.23-0.98) in the ESRD group vs. 1.54 (95% CI, 1.00-2.39) in the no-ESRD group.

CONCLUSIONS

The interaction effect between ESRD and TTM on neurologic outcome was positive in adult OHCA initial survivors with presumed cardiac etiology.

The Risk of Stroke and Stroke Type in Patients With Atrial Fibrillation and Chronic Kidney Disease

Background:

Atrial fibrillation (AF) and chronic kidney disease (CKD) are known to increase the risk of stroke.

Objectives:

We set out to examine the risk of stroke by kidney function and albuminuria in patients with and without AF.

Design:

Retrospective cohort study.

Settings:

Ontario, Canada.

Participants:

A total of 736 666 individuals (>40 years) from 2002 to 2015.

Measurements:

New-onset AF, albumin-to-creatinine ratio (ACR), and an estimated glomerular filtration rate (eGFR).

Methods:

A total of 39 120 matched patients were examined for the risk of ischemic, hemorrhagic, or any stroke event, accounting for the competing risk of all-cause mortality. Interaction terms for combinations of ACR/eGFR and the outcome of stroke with and without AF were examined.

Results:

In a total of 4086 (5.2%) strokes (86% ischemic), the presence of AF was associated with a 2-fold higher risk for any stroke event and its subtypes of ischemic and hemorrhagic stroke. Across eGFR levels, the risk of stroke was 2-fold higher with the presence of AF except for low levels of eGFR (eGFR < 30 mL/min/1.73 m², hazard ratio [HR]: 1.38, 95% confidence interval [CI]: 0.99-1.92). Similarly across ACR levels, the risk of stroke was 2-fold higher except for high levels of albuminuria (ACR > 30 mg/g, HR: 1.61, 95% CI: 1.31-1.99). The adjusted risk of stroke with AF differed by combinations of ACR and eGFR categories (interaction P value = .04) compared with those without AF. Both stroke types were more common in patients with AF, and ischemic stroke rates differed significantly by eGFR and ACR categories.

Limitations:

Medication information was not included.

Conclusions:

Patients with CKD and AF are at a high risk of total, ischemic, and hemorrhagic strokes; the risk is highest with lower eGFR and higher ACR and differs based on eGFR and the degree of ACR.

Intracranial haemorrhage detected by cerebral computed tomography after falls in hospital acute medical wards

Background

There is little published data on brain imaging and intracranial haemorrhage after hospital inpatient falls. Imaging protocols for inpatient falls have been adopted from head injury guidelines developed from data in patients presenting to the Emergency Department. We sought to describe the use of brain computed tomography (CT) following inpatient falls, and determine the incidence and potential risk factors for intracranial haemorrhage.

Methods

We identified inpatient falls in acute medical wards at Monash Health, a large hospital network in the southeast region of Melbourne in Australia, from the incident reporting system during a 32 month period. We examined the post-fall medical assessment form, neurological observation chart and the diagnostic imaging system for details of the fall and brain CT findings. We used survival analysis to evaluate the timeliness of brain imaging and determined potential risk factors for intracranial haemorrhage by logistic regression.

Results

From 934 falls in 789 medical inpatients, 191 brain CT scans were performed. The median age of patients was 77 years. Only 55% of falls were from standing height and 24% experienced a head strike. Less than 10% of patients received an urgent scan within one hour, and timeliness of imaging was influenced by anticoagulation status rather than guideline determination of urgency. The overall incidence of intracranial haemorrhage was 0.9%. The factors associated with intracranial haemorrhage were head strike, anticoagulation, loss of consciousness or amnesia, drop in Glasgow Coma Scale and advanced chronic kidney disease.

Conclusions

The incidence of intracranial haemorrhage was low as most inpatient falls were at low risk for head injury. Research is needed to determine if guidelines specific for hospital inpatients may reduce unnecessary scans without compromising case detection, and improve timeliness of urgent scans.

A prospective, randomized, pilot trial of a polyethylene glycol (PEG)-coated collagen patch (Hemopatch®) for intraoperative hemostasis during deceased donor renal transplant

INTRODUCTION

The objective of this study was to evaluate the safety and feasibility of using a polyethylene glycol (PEG)-coated collagen patch (Hemopatch^®) in patients undergoing deceased donor renal transplant. The primary outcome was the amount of intraoperative estimated blood loss in those patients receiving the patch compared to without. Secondary outcomes were the subjective achievement of hemostasis, perigraft collection, and drop in hemoglobin 48 hours postoperatively.

METHODS

We performed a single-center, prospective, randomized trial. Patients scheduled to undergo deceased donor renal transplant surgery were randomized to receive the PEG-coated patch or standard hemostasis (i.e., electrocautery and clips).

RESULTS

A total of 30 patients were enrolled over 15 months and randomized to receive the PEG-coated patch (n=15) or standard hemostasis (n=15). The mean age was 62.5 years. As determined by the operating surgeon, hemostasis was successfully achieved in all 15 cases using the PEG-coated patch. In the PEG-coated patch group, there was a trend towards less estimated blood loss (237 cc vs. 327 cc; p=0.11) and a lower drop in hemoglobin 48 hours postoperatively (22.27 g/L vs. 29.53 g/L; p=0.09) compared to the standard hemostasis group. Perigraft collection was similar between groups (27% vs. 40%; p=0.43). Subgroup analysis on patients who received anticoagulation therapy revealed no significant difference in blood loss between groups.

CONCLUSIONS

Based on our single-center experience, the PEG-coated patch (Hemopatch^®) is a safe and feasible option to aid hemostasis during deceased donor renal transplant surgery. Hemostasis was successfully achieved in all cases using the PEG-coated patch.

Chronic kidney disease in the pathogenesis of acute ischemic stroke

Chronic kidney disease has a graded and independent inverse impact on cerebrovascular health. Both thrombotic and hemorrhagic complications are highly prevalent in chronic kidney disease patients. Growing evidence suggests that in chronic kidney disease patients, ischemic strokes are more common than hemorrhagic strokes. Chronic kidney disease is asymptomatic until an advanced stage, but mild to moderate chronic kidney disease incites various pathogenic mechanisms such as inflammation, oxidative stress, neurohormonal imbalance, formation of uremic toxins and vascular calcification which damage the endothelium and blood vessels. Cognitive dysfunction, dementia, transient infarcts, and white matter lesions are widespread in mild to moderate chronic kidney disease patients. Uremic toxins produced after chronic kidney disease can pass through the blood-brain barrier and mediate cognitive dysfunction and neurodegeneration. Furthermore, chronic kidney disease precipitates vascular risk factors that can lead to atherosclerosis, hypertension, atrial fibrillation, and diabetes. Chronic kidney disease also exacerbates stroke pathogenesis, worsens recovery outcomes, and limits the eligibility of stroke patients to receive available stroke therapeutics. This review highlights the mechanisms involved in the advancement of chronic kidney disease and its possible association with stroke.

Endothelial dysfunction and low-grade inflammation in the transition to renal replacement therapy

Introduction

End-stage renal disease (ESRD) strongly associates with cardiovascular disease (CVD) risk. This risk is not completely mitigated by renal replacement therapy. Endothelial dysfunction (ED) and low-grade inflammation (LGI) may contribute to the increased CVD risk. However, data on serum biomarkers of ED and LGI during the transition to renal replacement therapy (dialysis and kidney transplantation) are scarce.

Methods

We compared serum biomarkers of ED and LGI between 36 controls, 43 participants with chronic kidney disease (CKD) stage 5 non-dialysis (CKD5-ND), 20 participants with CKD stage 5 hemodialysis (CKD5-HD) and 14 participants with CKD stage 5 peritoneal dialysis (CKD5-PD). Further, in 34 and 15 participants repeated measurements were available during the first six months following dialysis initiation and kidney transplantation, respectively. Serum biomarkers of ED (sVCAM-1, E-selectin, P-selectin, thrombomodulin, sICAM-1, sICAM-3) and LGI (hs-CRP, SAA, IL-6, IL-8, TNF-α) were measured with a single- or multiplex array detection system based on electro-chemiluminescence technology.

Results

In linear regression analyses adjusted for potential confounders, participants with ESRD had higher levels of most serum biomarkers of ED and LGI than controls. In addition, in CKD5-HD levels of serum biomarkers of ED and LGI were largely similar to those in CKD5-ND. In contrast, in CKD5-PD levels of biomarkers of ED were higher than in CKD5-ND and CKD5-HD. Similarly, in linear mixed model analyses sVCAM-1, thrombomodulin, sICAM-1 and sICAM-3 increased after PD initiation. In contrast, incident HD patients showed an increase in sVCAM-1, P-selectin and TNF-α, but a decline of hs-CRP, SAA and IL-6. Further, following kidney transplantation sVCAM-1, thrombomodulin, sICAM-3 and TNF-α were lower at three months post-transplantation and remained stable in the three months thereafter.

Conclusions

Levels of serum biomarkers of ED and LGI were higher in ESRD as compared with controls. In addition, PD initiation and, less convincingly, HD initiation may increase levels of selected serum biomarkers of ED and LGI on top of uremia per se. In contrast to dialysis, several serum biomarkers of ED and LGI markedly declined following kidney transplantation.

Effect of quinolinic acid - A uremic toxin from tryptophan metabolism - On hemostatic profile in rat and mouse thrombosis models

PURPOSE

We aimed to determine the effect of quinolinic acid (QA) on hemostasis in rat and mouse models of thrombosis.

MATERIAL AND METHODS

Wistar rats (male, n = 72) received QA dissolved in drinking water in doses of 3, 10, 30 mg/kg or pure drinking water (vehicle control group -VEH) for 14 days. On the 14^th day of the experiment the effect of QA on hemostasis was evaluated using electrically induced arterial thrombosis model. The following parameters were measured: thrombus weight, hematology, thromboelastometric (ROTEM) parameters, TXA₂ and 6-keto-PGF_1α concentration, coagulation and fibrinolytic markers activity and concentration. GFP mice (male, n = 30) were assigned to the group receiving QA (30 mg/kg) or VEH for 14 days and to the group receiving: single intravenous dose of QA (30 mg/kg) or VEH or the same dose of QA and anti-CD31 (platelet endothelial cell adhesion molecule-1, PECAM-1) antibody conjugated with Alexa Fluor 647. The effect of QA on hemostasis was evaluated in the model of laser-induced injury of mesentery vein using intravital confocal microscopy.

RESULTS

Administering QA for 14 days resulted in a divergent, depending on dose, increase in concentration of active form of tPA and PAI-1 and concentration of total PAI-1 and PAP complexes in rats' plasma. In turn, administering QA for 14 days in mice revealed its prothrombotic activity, while single-dose IV administration revealed its antithrombotic activity, through the up-regulation of PECAM-1 expression.

CONCLUSIONS

We demonstrated the first evidence for the opposite biological effects of QA on hemostasis in rat and mouse thrombosis models.

Revascularization Strategies in Patients with Chronic Kidney Disease and Acute Coronary Syndromes

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is a highly prevalent condition that increases the incidence and complexity of acute coronary syndrome (ACS). The purpose of this review is to summarize current evidence, uncertainties, and opportunities in the management of patients with CKD and ACS, with a focus on revascularization.

RECENT FINDINGS

Patients with CKD have been systematically under-represented or excluded from clinical trials in ACS. Available data, however, demonstrates that although patients with CKD and ACS benefit from revascularization, they are also less likely to receive recommended medical and revascularization therapies when compared to patients with normal kidney function. Despite the increased short-term risk of major morbidity and mortality, patients with CKD and ACS should be considered for an early invasive strategy while also trying to mitigate the risks of procedural related complications. Until evidence emerges from randomized clinical trials, the decision about revascularization strategy should involve multi-disciplinary collaboration, heart team consensus, and patient shared decision-making.

Transradial access versus transfemoral access: a comparison of outcomes and efficacy in reducing hemorrhagic events

Introduction: The radial artery is currently the most widely used access site for PCI procedures both acute and stable patient settings. Thanks to advantages in pharmacological therapy as well as in interventional devices, the rate of ischemic complications following PCI has significantly decreased. Nevertheless, this has been counterbalanced by an increased risk of periprocedural and late bleeding event, that can occur both at access and non-access sites. Choice of access site for PCI is of paramount importance to reduce the risk of access-related bleeding events. Areas covered: The aim of this review is to provide an overview of the actual available evidence comparing the transradial versus transfemoral approach to reduce hemorrhagic events. The most robust evidence comes from large randomized trials, partly also from observational registries, which compared the transradial and transfemoral approach. Expert opinion: Results show that radial access has proved to be decisive in reducing the incidence of hemorrhagic events. Furthermore, it showed a significant reduction in mortality and AKI compared to transfemoral access. However, increased experience in the use of the radial approach has led to less practice in the use of the femoral approach, which may be useful in cases of emergency, complications or inability to use the radial artery.

Novel Model to Predict Gastrointestinal Bleeding During Left Ventricular Assist Device Support

BACKGROUND

Gastrointestinal bleeding (GIB) is a leading cause of morbidity during continuous-flow left ventricular assist device (CF-LVAD) support. GIB risk assessment could have important implications for candidate selection, informed consent, and postimplant therapeutic strategies. The aim of the study is to derive and validate a predictive model of GIB in CF-LVAD patients.

METHODS AND RESULTS

CF-LVAD recipients at the Utah Transplantation Affiliated Hospitals program between 2004 and 2017 were included. GIB associated with a decrease in hemoglobin ≥2 g/dL was the primary end point. A weighted score comprising preimplant variables independently associated with GIB was derived and internally validated. A total of 351 patients (median age, 59 years; 82% male) were included. After a median of 196 days, GIB occurred in 120 (34%) patients. Independent predictors of GIB included age >54 years, history of previous bleeding, coronary artery disease, chronic kidney disease, severe right ventricular dysfunction, mean pulmonary artery pressure <18 mm Hg, and fasting glucose >107 mg/dL. A weighted score termed Utah bleeding risk score, effectively stratified patients based on their probability of GIB: low (0-1 points) 4.8%, intermediate (2-4) 39.8%, and high risk (5-9) 83.8%. Discrimination was good in the development sample (c-index: 0.83) and after internal bootstrap validation (c-index: 0.74).

CONCLUSIONS

The novel Utah bleeding risk score is a simple tool that can provide personalized GIB risk estimates in CF-LVAD patients. This scoring system may assist clinicians and investigators in designing tailored risk-based strategies aimed at reducing the burden posed by GIB in the individual CF-LVAD patient and healthcare systems.

Benefits and Harms of Oral Anticoagulant Therapy in Chronic Kidney Disease: A Systematic Review and Meta-analysis

BACKGROUND

Effects of oral anticoagulation in chronic kidney disease (CKD) are uncertain.

PURPOSE

To evaluate the benefits and harms of vitamin K antagonists (VKAs) and non-vitamin K oral anticoagulants (NOACs) in adults with CKD stages 3 to 5, including those with dialysis-dependent end-stage kidney disease (ESKD).

DATA SOURCES

English-language searches of MEDLINE, EMBASE, and Cochrane databases (inception to February 2019); review bibliographies; and ClinicalTrials.gov (25 February 2019).

STUDY SELECTION

Randomized controlled trials evaluating VKAs or NOACs for any indication in patients with CKD that reported efficacy or bleeding outcomes.

DATA EXTRACTION

Two authors independently extracted data, assessed risk of bias, and rated certainty of evidence.

DATA SYNTHESIS

Forty-five trials involving 34 082 participants who received anticoagulation for atrial fibrillation (AF) (11 trials), venous thromboembolism (VTE) (11 trials), thromboprophylaxis (6 trials), prevention of dialysis access thrombosis (8 trials), and cardiovascular disease other than AF (9 trials) were included. All but the 8 trials involving patients with ESKD excluded participants with creatinine clearance less than 20 mL/min or estimated glomerular filtration rate less than 15 mL/min/1.73 m2. In AF, compared with VKAs, NOACs reduced risks for stroke or systemic embolism (risk ratio [RR], 0.79 [95% CI, 0.66 to 0.93]; high-certainty evidence) and hemorrhagic stroke (RR, 0.48 [CI, 0.30 to 0.76]; moderate-certainty evidence). Compared with VKAs, the effects of NOACs on recurrent VTE or VTE-related death were uncertain (RR, 0.72 [CI, 0.44 to 1.17]; low-certainty evidence). In all trials combined, NOACs seemingly reduced major bleeding risk compared with VKAs (RR, 0.75 [CI, 0.56 to 1.01]; low-certainty evidence).

LIMITATION

Scant evidence for advanced CKD or ESKD; data mostly from subgroups of large trials.

CONCLUSION

In early-stage CKD, NOACs had a benefit-risk profile superior to that of VKAs. For advanced CKD or ESKD, there was insufficient evidence to establish benefits or harms of VKAs or NOACs.

PRIMARY FUNDING SOURCE

None. (PROSPERO: CRD42017079709).

Mild bleeding disorders: what every clinician should know

Patients with mild bleeding disorders are under-recognized and frequently present to general physicians. The underlying reasons for bleeding are multifactorial. There is little evidence to guide diagnostic and management decision making in patients with mild bleeding disorders. This article outlines different types of mild bleeding disorders, with a particular focus on bleeding associated with low levels of von Willebrand factor and mild platelet defects. It gives practical, evidence-based advice on the investigation and management of patients with a suspected or known mild bleeding disorder, considering the scenarios of an acute bleed, stable outpatient, peri-surgical management and thrombosis. Patients with a mild bleeding disorder have variable bleeding because of the interplay of genetic and environmental factors. The clinical history remains of utmost importance in their general management. Liaison with a specialist centre, multidisciplinary assessment and a careful judgement of the balance of risk in each individual circumstance is required to safely manage these patients.

Anticoagulation in Patients With Advanced Chronic Kidney Disease: Walking the Fine Line Between Benefit and Harm

Chronic kidney disease affects more than 3 million Canadians and is highly associated with cardiovascular diseases that require anticoagulation, such as atrial fibrillation and venous thromboembolism. Patients with chronic kidney disease are at a problematic crossroads; they are at high risk of thrombotic conditions requiring anticoagulation and bleeding complications due to anticoagulation. The limited high-quality clinical evidence to guide decision-making in this area further compounds the dilemma. In this review, we discuss the physiology and epidemiology of bleeding and thrombosis in patients with kidney disease. We specifically focus on patients with advanced kidney disease (estimated glomerular filtration rate ≤ 30 mL/min) or who are receiving dialysis and focus on the nephrologist perspective regarding these issues. We summarize the existing evidence for anticoagulation use in the prevention of stroke with atrial fibrillation and provide practical clinical recommendations for considering anticoagulation use in this population. Last, we examine specific scenarios such as the use of a glomerular filtration rate estimating equation and dosing, the use of existing prediction tools for stroke and hemorrhage risk, current patterns of anticoagulation use (including during the dialysis procedure), and vascular calcification with vitamin K antagonist use in patients with chronic kidney disease.

Oral Anticoagulants in Patients With Atrial Fibrillation and End-Stage Renal Disease

The role of oral anticoagulants (OAC) in atrial fibrillation (AF) is well established. However, none of the randomized controlled trials included patients with end-stage renal disease (ESRD) leaving a lack of evidence in this large, challenging and unique patient group. Patients on hemodialysis (HD) with AF have additional risk factors for stroke due to vascular comorbidities, HD treatment, age, and diabetes. Conversely, they are also at increased risk of major bleeding due to uremic platelet impairment. Anticoagulants increase bleeding risk in patients with ESRD and HD up to 10-fold compared with non chronic kidney disease (CKD) patients on warfarin. There are conflicting data and recommendations regarding use of OACs in ESRD which will be reviewed in this article. We conclude by proposing a modified strategy for OAC use in ESRD based on the latest evidence.