Cardiovascular complications in chronic dialysis patients

Update on Hemodialysis-Induced Multiorgan Ischemia: Brains and Beyond

Hemodialysis is a life-saving treatment for patients with kidney failure. However, patients requiring hemodialysis have a 10-20 times higher risk of cardiovascular morbidity and mortality than that of the general population. Patients encounter complications such as episodic intradialytic hypotension, abnormal perfusion to critical organs (heart, brain, liver, and kidney), and damage to vulnerable vascular beds. Recurrent conventional hemodialysis exposes patients to multiple episodes of circulatory stress, exacerbating and being aggravated by microvascular endothelial dysfunction. This promulgates progressive injury that leads to irreversible multiorgan injury and the well-documented higher incidence of cardiovascular disease and premature death. This review aims to examine the underlying pathophysiology of hemodialysis-related vascular injury and consider a range of therapeutic approaches to improving outcomes set within this evolved rubric.‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬.

Hemodiafiltration: Technical and Medical Insights

Despite the significant medical and technical improvements in the field of dialytic renal replacement modalities, morbidity and mortality are excessively high among patients with end-stage kidney disease, and most interventional studies yielded disappointing results. Hemodiafiltration, a dialysis method that was implemented in clinics many years ago and that combines the two main principles of hemodialysis and hemofiltration-diffusion and convection-has had a positive impact on mortality rates, especially when delivered in a high-volume mode as a surrogate for a high convective dose. The achievement of high substitution volumes during dialysis treatments does not only depend on patient characteristics but also on the dialyzer (membrane) and the adequately equipped hemodiafiltration machine. The present review article summarizes the technical aspects of online hemodiafiltration and discusses present and ongoing clinical studies with regards to hard clinical and patient-reported outcomes.

Impact of Hydrophilic Modification of Synthetic Dialysis Membranes on Hemocompatibility and Performance

The dialyzer is the core element in the hemodialysis treatment of patients with end-stage kidney disease (ESKD). During hemodialysis treatment, the dialyzer replaces the function of the kidney by removing small and middle-molecular weight uremic toxins, while retaining essential proteins. Meanwhile, a dialyzer should have the best possible hemocompatibility profile as the perpetuated contact of blood with artificial surfaces triggers complement activation, coagulation and immune cell activation, and even low-level activation repeated chronically over years may lead to undesired effects. During hemodialysis, the adsorption of plasma proteins to the dialyzer membrane leads to a formation of a secondary membrane, which can compromise both the uremic toxin removal and hemocompatibility of the dialyzer. Hydrophilic modifications of novel dialysis membranes have been shown to reduce protein adsorption, leading to better hemocompatibility profile and performance stability during dialysis treatments. This review article focuses on the importance of performance and hemocompatibility of dialysis membranes for the treatment of dialysis patients and summarizes recent studies on the impact of protein adsorption and hydrophilic modifications of membranes on these two core elements of a dialyzer.

Long-term impacts of different dialysis modalities on right ventricular function in patients with end-stage renal disease

BACKGROUND

Right ventricular dysfunction is a major cause of heart failure and mortality in end-stage renal disease patients. Scarce data is available regarding the comparison of echocardiographic right ventricular function in end-stage renal disease patients on hemodialysis (HD) and peritoneal dialysis (PD). The aim of the study was to evaluate the long-term impacts of different dialysis modalities on right ventricular function assessed by conventional echocardiography, in end-stage renal disease patients with preserved left ventricular function.

METHODS

The study included 120 patients grouped as follows: PD (n = 40), HD with arterio-venous fistula (n = 40), and healthy control subjects (n = 40). Conventional echocardiography was performed on all patients. A classification of right ventricular function was defined in HD patients by using tricuspid annular plane systolic excursion (TAPSE), right ventricular myocardial performance index (RV-MPI), fractional area change (FAC), and tricuspid lateral annulus systolic velocity (Sa) values. Correlation analysis was performed by using the right ventricular dysfunction score, clinical, and echocardiographic parameters.

RESULTS

The mean age of the study population was 51.9 ± 13.1 years and 47.5% were females. TAPSE and Sa velocity were found to be significantly lower and RV-MPI was significantly higher in patients undergoing HD, compared with control and PD patients. Logistic regression analysis showed that HD treatment was an independent risk factor for developing right ventricular dysfunction.

CONCLUSION

RV function was impaired in patients undergoing HD compared with patients on PD.

Atherosclerosis Specific Features in Chronic Kidney Disease (CKD)

Atherosclerosis is the major cause of cardiovascular disease, leading to a high mortality rate worldwide. Several risk factors are known to favor atherogenesis, among which are high blood pressure, smoking, diabetes mellitus, and others. Chronic kidney disease is another serious health problem associated with significant health care costs, morbidity, and mortality. Chronic kidney disease shares several risk factors with atherosclerosis and cardiovascular diseases, such as hypertension and diabetes mellitus. Additional risk factors for cardiovascular disease development should be considered in patients with chronic kidney disease. Interestingly, patients suffering from chronic kidney disease are more prone to cardiovascular problems than the general population. Moreover, chronic kidney disease is characterized by an increased atherosclerotic burden from the very early stages. The purpose of this review was to summarize data on atherosclerosis in chronic kidney disease, highlighting the specific features of the disease combination.

Anticoagulation in patients with kidney failure on dialysis: factor XI as a therapeutic target

Chronic kidney disease is present in almost 10% of the world population and is associated with excess mortality and morbidity. Reduced glomerular filtration rate and the presence and extent of proteinuria, key domains of chronic kidney disease, have both been shown to be strong and independent risk factors for cardiovascular disease. Patients with kidney failure requiring dialysis are at highest risk for cardiovascular events (e.g., stroke or myocardial infarction), and of developing chronic cardiovascular conditions, such as heart failure. Despite the high burden of cardiovascular disease, there is a paucity of evidence supporting therapies to reduce this risk. Although long-term anticoagulant treatment has the potential to prevent thromboembolism in persons with kidney failure on dialysis, this possibility remains understudied. The limited data available on anticoagulation in patients with kidney failure has focused on vitamin K antagonists or direct oral anticoagulants that inhibit thrombin or factor (F) Xa. The risk of bleeding is a major concern with these agents. However, FXI is emerging as a potential safer target for new anticoagulants because FXI plays a greater part in thrombosis than in hemostasis. In this article, we (i) explain the rationale for considering anticoagulation therapy in patients with kidney failure to reduce atherothrombotic events, (ii) highlight the limitations of current anticoagulants in this patient population, (iii) explain the potential benefits of FXI inhibitors, and (iv) summarize ongoing studies investigating FXI inhibition in patients with kidney failure on dialysis.

Fluid Management During Kidney Transplantation: A Consensus Statement of the Committee on Transplant Anesthesia of the American Society of Anesthesiologists

BACKGROUND

Intraoperative fluid management may affect the outcome after kidney transplantation. However, the amount and type of fluid administered, and monitoring techniques vary greatly between institutions and there are limited prospective randomized trials and meta-analyses to guide fluid management in kidney transplant recipients.

METHODS

Members of the American Society of Anesthesiologists (ASA) committee on transplantation reviewed the current literature on the amount and type of fluids (albumin, starches, 0.9% saline, and balanced crystalloid solutions) administered and the different monitors used to assess fluid status, resulting in this consensus statement with recommendations based on the best available evidence.

RESULTS

Review of the current literature suggests that starch solutions are associated with increased risk of renal injury in randomized trials and should be avoided in kidney donors and recipients. There is no evidence supporting the routine use of albumin solutions in kidney transplants. Balanced crystalloid solutions such as Lactated Ringer are associated with less acidosis and may lead to less hyperkalemia than 0.9% saline solutions. Central venous pressure is only weakly supported as a tool to assess fluid status.

CONCLUSIONS

These recommendations may be useful to anesthesiologists making fluid management decisions during kidney transplantation and facilitate future research on this topic.

Plasma Catestatin Levels and Advanced Glycation End Products in Patients on Hemodialysis

Catestatin (CST) is a pleiotropic peptide involved in cardiovascular protection with its antihypertensive and angiogenic effects. Considering that patients with end-stage renal disease (ESRD) who are undergoing hemodialysis (HD) are associated with higher cardiovascular risk, the aim of this study was to investigate plasma CST levels in HD patients, compare them to healthy controls and evaluate possible CST associations with advanced glycation end products (AGEs) and laboratory, anthropometric and clinical parameters. The study included 91 patients on HD and 70 healthy controls. Plasma CST levels were determined by an enzyme-linked immunosorbent assay in a commercially available diagnostic kit, while AGEs were determined using skin autofluorescence. Plasma CST levels were significantly higher in the HD group compared to the controls (32.85 ± 20.18 vs. 5.39 ± 1.24 ng/mL, p < 0.001) and there was a significant positive correlation between CST and AGEs (r = 0.492, p < 0.001). Furthermore, there was a significant positive correlation between plasma CST levels with both the Dialysis Malnutrition Score (r = 0.295, p = 0.004) and Malnutrition-Inflammation Score (r = 0.290, p = 0.005). These results suggest that CST could be playing a role in the complex pathophysiology of ESRD/HD and that it could affect the higher cardiovascular risk of patients on HD.

Predicting the Appearance of Hypotension During Hemodialysis Sessions Using Machine Learning Classifiers

A patient suffering from advanced chronic renal disease undergoes several dialysis sessions on different dates. Several clinical parameters are monitored during the different hours of any of these sessions. These parameters, together with the information provided by other parameters of analytical nature, can be very useful to determine the probability that a patient may suffer from hypotension during the session, which should be specially watched since it represents a proven factor of possible mortality. However, the analytical information is not always available to the healthcare personnel, or it is far in time, so the clinical parameters monitored during the session become key to the prevention of hypotension. This article presents an investigation to predict the appearance of hypotension during a dialysis session, using predictive models trained from a large dialysis database, which contains the clinical information of 98,015 sessions corresponding to 758 patients. The prediction model takes into account up to 22 clinical parameters measured five times during the session, as well as the gender and age of the patient. This model was trained by means of machine learning classifiers, providing a success in the prediction higher than 80%.

Current and novel imaging techniques to evaluate myocardial dysfunction during hemodialysis

PURPOSE OF REVIEW

Patients on hemodialysis have significantly higher rates of cardiovascular mortality resulting from a multitude of myocardial dysfunctions. Current imaging modalities allow independent assessment of cardiac morphology, contractile function, coronary arteries and cardiac perfusion. Techniques such as cardiac computed tomography (CT) imaging have been available for some time, but have not yet had widespread adoption because of technical limitations related to cardiac motion, radiation exposure and safety of contrast agents in kidney disease.

RECENT FINDINGS

Novel dynamic contrast-enhanced (DCE) CT imaging can be used to acquire high-resolution cardiac images, which simultaneously allow the assessment of coronary arteries and the quantitative measurement of myocardial perfusion. The advancement of recent CT scanners and cardiac protocols have allowed noninvasive imaging of the whole heart in a single imaging session with minimal cardiac motion artefact and exposure to radiation.

SUMMARY

DCE-CT imaging in clinical practice would allow comprehensive evaluation of the structure, function, and hemodynamics of the heart in a short, well tolerated scanning session. It is an imaging tool enabling the study of myocardial dysfunction in dialysis patients, who have greater cardiovascular risk than nonrenal cardiovascular disease populations, both at rest and under cardiac stress associated with hemodialysis itself.

Efficacy of Implantable Cardioverter-defibrillators for Secondary Prevention of Sudden Cardiac Death in Patients with End-stage Renal Disease

End-stage renal disease (ESRD) constitutes a major burden on the health-care system in the United States, with more than 300,000 patients nationwide being treated with renal replacement therapy. Very few studies to date have evaluated the benefit of implantable cardioverter-defibrillator (ICD) implantation for secondary prevention in patients with ESRD. In this study, we evaluated the efficacy of secondary-prevention ICDs in reducing all-cause mortality in patients on dialysis using the United States Renal Data System (USRDS) database. We queried the USRDS for relevant data between 2004 and 2010. Patients with diagnoses of ventricular fibrillation (VF), ventricular tachycardia (VT), or sudden cardiac arrest (SCA) were included in the study. Patients were excluded from the analysis if they were younger than 18 years; had missing age, sex, or race/ethnicity information; had experienced myocardial infarction; or had an ICD in situ at the time of VF, VT, or SCA diagnosis. The primary endpoint of this study was to determine the efficacy of secondary-prevention ICDs in reducing all-cause mortality in patients on dialysis. A total of 1,442 patients (3.4%) with ESRD had ICD insertion. Patients who received an ICD were predominantly younger, white males with lower Charlson Comorbidity Index and with fewer cardiovascular events. Survival at two years was 53% among those with an ICD relative to 27% among those without an ICD. In this study, we observed a substantial decrease in mortality in patients receiving an ICD for secondary prevention when compared with a cohort of similar patients with a history of VF, VT, or SCA.

Using Artificial Intelligence Resources in Dialysis and Kidney Transplant Patients: A Literature Review

BACKGROUND

The purpose of this review is to depict current research and impact of artificial intelligence/machine learning (AI/ML) algorithms on dialysis and kidney transplantation. Published studies were presented from two points of view: What medical aspects were covered? What AI/ML algorithms have been used?

METHODS

We searched four electronic databases or studies that used AI/ML in hemodialysis (HD), peritoneal dialysis (PD), and kidney transplantation (KT). Sixty-nine studies were split into three categories: AI/ML and HD, PD, and KT, respectively. We identified 43 trials in the first group, 8 in the second, and 18 in the third. Then, studies were classified according to the type of algorithm.

RESULTS

AI and HD trials covered: (a) dialysis service management, (b) dialysis procedure, (c) anemia management, (d) hormonal/dietary issues, and (e) arteriovenous fistula assessment. PD studies were divided into (a) peritoneal technique issues, (b) infections, and (c) cardiovascular event prediction. AI in transplantation studies were allocated into (a) management systems (ML used as pretransplant organ-matching tools), (b) predicting graft rejection, (c) tacrolimus therapy modulation, and (d) dietary issues.

CONCLUSIONS

Although guidelines are reluctant to recommend AI implementation in daily practice, there is plenty of evidence that AI/ML algorithms can predict better than nephrologists: volumes, Kt/V, and hypotension or cardiovascular events during dialysis. Altogether, these trials report a robust impact of AI/ML on quality of life and survival in G5D/T patients. In the coming years, one would probably witness the emergence of AI/ML devices that facilitate the management of dialysis patients, thus increasing the quality of life and survival.

[Blood pressure variability in hemodialysis patients: prognostic significance and treatment possibilities]

A present review is devoted to the current state of the problem of blood pressure variability (BPV) in hemodialysis patients. The BPV classification and clinical significance of BPV metrics are discussed. The results of cohort and randomized studies on the high BPV influence on outcomes in hemodialysis patients, as well as on the possibilities of antihypertensive drugs in the treatment of high BPV in dialysis patients, are presented.

Role of direct oral anticoagulants in patients with kidney disease

The anticoagulation field is experiencing a renaissance that began with regulatory approval of the direct thrombin inhibitor dabigatran, a direct oral anticoagulant (DOAC), in 2010. The DOAC medication class has rapidly evolved to include the additional approval of 4 direct factor Xa inhibitors. Commensurately, DOAC use has increased and collectively account for the majority of new anticoagulant prescriptions. Despite exclusion of patients with moderate-to-severe kidney disease from most pivotal DOAC trials, DOACs are increasingly used in this setting. An advantage of DOACs is similar or improved antithrombotic efficacy with less bleeding risk when compared with traditional agents. Several post hoc analyses, retrospective studies, claims data studies, and meta-analyses suggest that these benefits extend to patients with kidney disease. However, the lack of randomized controlled trial data in specific kidney disease settings, with their unique pathophysiology, should be a call to action for the kidney community to systematically study these agents, especially because early data suggest that DOACs may pose less risk of anticoagulant-related nephropathy than do vitamin K antagonists. Most DOACs are renally cleared and are significantly protein bound in circulation; thus, the pharmacokinetics of these drugs are influenced by reduced renal function and proteinuria. DOACs are susceptible to altered metabolism by P-glycoprotein inhibitors and inducers, including drugs commonly used for the management of kidney disease comorbidities. We summarize the currently available literature on DOAC use in kidney disease and illustrate knowledge gaps that represent important opportunities for prospective investigation.

[Cardiac arrhythmias in patients with chronic kidney disease]

Patients with chronic kidney disease are at increased risk for cardiovascular morbidity and mortality, with the increased prevalence of supraventricular and ventricular arrhythmia being an important factor. The underlying pathomechanisms are diverse and mainly cause increasing atrial and ventricular fibrosis with so-called cardiac remodeling. In particular, patients with advanced kidney disease were excluded from many pioneering clinical trials, so there are no clear guidelines in the treatment of cardiac arrhythmia for these patients. The potential benefits of implantable cardioverter defibrillator (ICD) therapy for the prevention of sudden cardiac death or the benefits of anticoagulation for prevention of thromboembolic events in atrial fibrillation should therefore be evaluated individually for each patient with advanced kidney disease, taking comorbidities and the prognosis into account. When using antiarrhythmic drugs, a dose adjustment may be necessary depending on the pharmacokinetics and metabolism. Although atrial fibrillation treatment by means of pulmonary vein isolation can lead to an improvement in kidney function, the success rate seems to be significantly reduced in the presence of advanced kidney disease. Overall, an individual therapy and treatment concept for each patient with advanced chronic kidney disease is advisable.

Additional hemoperfusion is associated with improved overall survival and self-reported sleep disturbance in patients on hemodialysis

Introduction:

Patients with maintenance hemodialysis have experienced long-standing sleep disturbance. In this study, we attempted to explore whether long-term hemoperfusion could improve sleep and increase the overall survival in hemodialysis patients.

Methods:

A total of 158 patients, who underwent routine hemodialysis, were assessed in this study. These patients were computer-matched into two groups, with one group including 80 patients with absolute hemodialysis and the other consisting of 78 cases with hemodialysis in combination with hemoperfusion. Hemoperfusion was performed 1–2 times biweekly, with each session lasting 2 h. Self-reported sleep disturbance was evaluated before and after the observational time (2-year period); sleep quality was measured using the Pittsburgh Sleep Quality Index.

Findings:

Using multivariate regression analyses, we found sleep duration was associated with age, diabetes, low income, pruritus, hyperphosphatemia, hypercalcemia, high parathyroid hormone, and hemoglobin ( P < 0.001). The overall survival rate of the hemodialysis in combination with hemoperfusion group was significantly higher than that of the absolute hemodialysis group ( P < 0.05) after adjusting for sex, age, and diabetes. A 2-year hemoperfusion therapy was associated with improved sleep disturbance and sleep efficiency; this was accompanied by an increase in nocturnal melatonin levels. Furthermore, there was a significant difference in the first hospitalization between the hemodialysis and hemodialysis in combination with hemoperfusion groups ( P < 0.01).

Discussion:

Our results indicated that hemoperfusion in combination with hemodialysis is associated with an increase in the overall survival and improved sleep disorders in hemodialysis patients.

Associations of vitamin K status with mortality and cardiovascular events in peritoneal dialysis patients

PURPOSE

Vitamin K deficiency, expressed by a high level of desphospho-uncarboxylated matrix GLA protein (dp-ucMGP), is highly prevalent in dialysis patients. However, the predictive ability of the vitamin K status remains unclear in continuous ambulatory peritoneal dialysis (CAPD) patients.

METHODS

158 prevalent CAPD patients with a median level of dp-ucMGP of 1093 (752, 1485) pmol/L were enrolled. Patient outcomes including all-cause mortality and cardiovascular events (CVEs) were recorded during follow-up. Survival curves were performed using Kaplan-Meier method, and the influences of dp-ucMGP on outcomes were analyzed by Cox regression models.

RESULTS

A total of 59 deaths and 82 new episodes of CVEs occurred during median follow-up of 31.4 ± 13.1 months (range: 3.8-48.0 months). Kaplan-Meier analysis revealed patients with higher dp-ucMGP levels (≥ 1093 pmol/L) had an increased risk for both mortality (P = 0.005) and CVEs (P < 0.001). Multivariable Cox regression confirmed that higher dp-ucMGP levels increase the mortality risk [hazard ratio (HR), 1.763; 95% CI 1.045-3.291] and CVEs (HR, 1.846; 95% CI 1.074-3.172). For every 100 pmol/L increase in serum dp-ucMGP, the adjusted HRs for mortality and CVEs were 1.054 (95% CI 1.008-1.106) and 1.034 (95% CI 1.012-1.089), respectively.

CONCLUSIONS

Vitamin K deficiency, as expressed by high dp-ucMGP levels, showed independently associations with mortality and CVEs in CAPD patients.

Fibroblast growth factor-23 promotes rhythm alterations and contractile dysfunction in adult ventricular cardiomyocytes

Background

Cardiac dysfunction and arrhythmia are common and onerous cardiovascular events in end-stage renal disease (ESRD) patients, especially those on dialysis. Fibroblast growth factor (FGF)-23 is a phosphate-regulating hormone whose levels dramatically increase as renal function declines. Beyond its role in phosphorus homeostasis, FGF-23 may elicit a direct effect on the heart. Whether FGF-23 modulates ventricular cardiac rhythm is unknown, prompting us to study its role on excitation–contraction (EC) coupling.

Methods

We examined FGF-23 in vitro actions on EC coupling in adult rat native ventricular cardiomyocytes using patch clamp and confocal microscopy and in vivo actions on cardiac rhythm using electrocardiogram.

Results

Compared with vehicle treatment, FGF-23 induced a significant decrease in rat cardiomyocyte contraction, L-type Ca2+ current, systolic Ca2+ transients and sarcoplasmic reticulum (SR) load and SR Ca2+-adenosine triphosphatase 2a pump activity. FGF-23 induced pro-arrhythmogenic activity in vitro and in vivo as automatic cardiomyocyte extracontractions and premature ventricular contractions. Diastolic spontaneous Ca2+ leak (sparks and waves) was significantly increased by FGF-23 via the calmodulin kinase type II (CaMKII)-dependent pathway related to hyperphosphorylation of ryanodine receptors at the CaMKII site Ser2814. Both contraction dysfunction and spontaneous pro-arrhythmic Ca2+ events induced by FGF-23 were blocked by soluble Klotho (sKlotho).

Conclusions

Our results show that FGF-23 reduces contractility and enhances arrhythmogenicity through intracellular Ca2+ mishandling. Blocking its actions on the heart by improving sKlotho bioavailability may enhance cardiac function and reduce arrhythmic events frequently observed in ESRD.

Changes of Left and Right Ventricle Mechanics and Function in Patients with End-Stage Renal Disease Undergoing Haemodialysis

Background and objectives: Chronic kidney disease (CKD) increases the risk of cardiovascular diseases even in its early stages and is associated with structural and functional cardiac abnormalities. The aim of this study was to use speckle-tracking echocardiography (STE) to evaluate left and right ventricle mechanics and function, markers of subclinical dysfunction in patients with end-stage renal disease (ESRD) undergoing haemodialysis. Methods: Patients with ESRD undergoing regular haemodialysis and with preserved left ventricle (LV) ejection fraction (EF) (n = 38) were enrolled in this retrospective study. The control group consisted of 32 age-matched persons with normal kidney function (glomerular filtration rate (GFR) >90 mL/min/1.73 m² according to Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)). Conventional 2D echocardiography and STE were performed in all patients. Results: 70 individuals, 31 (44.29%) males and 39 (55.71%) females, were included in the study. There were no significant differences in age, sex and body surface area between the groups. LV end diastolic diameter did not differ between the groups, while LV myocardial mass index was higher in the group of patients on haemodialysis (111.64 ± 27.99 versus 84.21 ± 16.99, p < 0.001) and LV diastolic dysfunction (LVDD) was found in 31 (81.6%) patients of this group. LV global longitudinal strain (GLS) (-22.43 ± 2.71 versus -24.73 ± 2.03, p < 0.001) and LV global circumferential strain (GCS) at the mitral valve and papillary muscles levels (-18.73 ± 3.49 versus -21.67 ± 2.22, p < 0.001; -18.64 ± 2.75 versus -20.42 ± 2.38, p = 0.005, respectively) were significantly lower in haemodialysis group patients. The parameters of the right ventricle (RV) free wall longitudinal function including RV GLS (-22.63 ± 3.04 versus -25.45 ± 2.48, p < 0.001), were reduced in haemodialysis patients compared with the controls. However, RV fractional area change (FAC) did not differ between the groups (p = 0.19). Conclusion: Patients with ESRD and preserved LV ejection fraction undergoing haemodialysis had a higher prevalence of LVDD and impaired LV longitudinal and circumferential deformation indices, as well as reduced RV longitudinal function and deformation parameters compared with the age-matched healthy controls. STE helps to detect subclinical LV and RV dysfunction in chronic haemodialysis patients.

Epidemiology and Prognostic Importance of Atrial Fibrillation in Kidney Transplant Recipients: A Meta-Analysis

This meta-analysis was conducted with the aims to summarize all available evidence on (1) prevalence of pre-existing atrial fibrillation (AF) and/or incidence of AF following kidney transplantation; (2) the outcomes of kidney transplant recipients with AF; and (3) the trends of estimated incidence of AF following kidney transplantation over time. A literature search was conducted utilizing MEDLINE, EMBASE, and the Cochrane Database from inception through March 2018. We included studies that reported (1) prevalence of pre-existing AF or incidence of AF following kidney transplantation or (2) outcomes of kidney transplant recipients with AF. Effect estimates from the individual study were extracted and combined utilizing random-effect, generic inverse variance method of DerSimonian and Laird. The protocol for this meta-analysis is registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42018086192). Eight cohort studies with 137,709 kidney transplant recipients were enrolled. Overall, the pooled estimated prevalence of pre-existing AF in patients undergoing kidney transplantation was 7.0% (95% CI: 5.6⁻8.8%) and pooled estimated incidence of AF following kidney transplantation was 4.9% (95% CI: 1.7⁻13.0%). Meta-regression analyses were performed and showed no significant correlations between year of study and either prevalence of pre-existing AF (p = 0.93) or post-operative AF after kidney transplantation (p = 0.16). The pooled odds ratios (OR) of mortality among kidney transplant recipients with AF was 1.86 (3 studies; 95% CI: 1.03⁻3.35). In addition, AF is also associated with death-censored allograft loss (2 studies; OR: 1.55, 95% CI: 1.02⁻2.35) and stroke (3 studies; OR: 2.54, 95% CI: 1.11⁻5.78) among kidney transplant recipients. Despite advances in medicine, incidence of AF following kidney transplant does not seem to decrease over time. In addition, there is a significant association of AF with increased mortality, allograft loss, and stroke after kidney transplantation.

Assessment of Atrial Fibrillation and Ventricular Arrhythmia Risk After Transplant in Patients With End-Stage Renal Disease by P-wave/QT Interval Dispersion, T-Wave Peak-End Interval, and T-Wave Peak-End/QT Interval Ratio

OBJECTIVES

The association between end-stage renal disease with atrial fibrillation and ventricular arrhythmias is well documented. The aim of this study was to investigate whether kidney transplant has any effect on P-wave dispersion, a predictor of atrial fibrillation and corrected QT interval dispersion, T-wave peak-end interval, and T-wave peak-end/corrected QT ratio, which are predictors of ventricular arrhythmias in patients with end-stage renal disease.

MATERIALS AND METHODS

In a retrospective study, 234 patients (125 kidney transplant and 109 healthy control patients) were examined. P-wave dispersion, corrected QT dispersion, T-wave peak-end interval, and T-wave peak-end/corrected QT ratio values before and 3, 6, and 12 months after transplant were calculated and compared in transplant recipients. Baseline values of the control group were compared with 12-month values of kidney transplant patients.

RESULTS

We observed a statistically significant decline in P-wave dispersion, corrected QT dispersion, T-wave peak-end interval, and T-wave peak-end/corrected QT ratio values among the pretransplant and 3-, 6-, and 12-month posttransplant measurements (P < .001 for all comparisons). However, the values of these measurements in the transplant group at 12 months were significantly higher than baseline values of the control group (P < .001 for all comparisons).

CONCLUSIONS

P-wave dispersion, corrected QT dispersion, T-wave peak-end interval, and T-wave peak-end/corrected QT ratio were shown to be attenuated after transplant, although they remained higher than baseline measurements in healthy individuals. These results indirectly offer that there may be a reduction in risk of atrial fibrillation and ventricular arrhythmias after transplant.

The efficacy of low-dose tadalafil in patients undergoing hemodialysis with end-stage renal disease

BACKGROUND

Erectile dysfunction (ED) is a disorder that is frequently observed in people with chronic kidney disease who undergo hemodialysis (HD). In the context of evidence-based medicine, we aimed to investigate the effect of low-dose tadalafil on sexual function in patients undergoing HD.

METHODS

The medical records of 30 males (aged 29-65 years) with end-stage renal disease (ESRD) on a HD program, and who had received 5 mg tadalafil twice weekly, were retrospectively evaluated. Changes in erectile and ejaculatory function were evaluated using the International Erectile Function Index questionnaire, the Erection Hardness Scale (EHS), and the Male Sexual Health Questionnaire (MSHQ).

RESULTS

The mean age of the patients was 47.6 ± 10.1 years, their mean body mass index was 24.3 ± 4.2 kg/m², their mean hemoglobin was 11.9 ± 0.9 g/dL, and their mean creatinine clearance was 5.8 ± 1.1 mL/min. At the third month of treatment, 36.6% of the patients had no ED, 40% had mild ED, 10% had mild-to-moderate ED, and 13.3% had moderate ED. The mean MSHQ scores (p < .05) and the mean EHS scores (p = .001) were significantly improved. There was no significant difference between Beck's Depression Inventory scores (p > .05), but Hamilton anxiety rate scores decreased significantly (p = .001). The quality-of-life score improved throughout the study period (p < .05).

CONCLUSIONS

Tadalafil therapy is an effective therapeutic option in patients with ESRD who undergo HD, not only for the treatment of ED, but also for ejaculatory function, with acceptable adverse effects.

Treatment effects of renin-angiotensin aldosterone system blockade on kidney failure and mortality in chronic kidney disease patients

BACKGROUND

Chronic kidney disease (CKD) is a leading cause of death before and after onset of end-stage renal disease (ESRD). Knowing treatments that can delay disease progression will lead to reduced mortality. We therefore aimed to estimate the effectiveness of renin angiotensin aldosterone system (RAAS) blockade on CKD progression.

METHODS

We conducted a retrospective CKD cohort at Ubon Ratchathani province, Thailand from 1997 to 2011. ESRD was defined as estimated glomerular filtration rate (eGFR) <15 ml/min/1.73 m2, dialysis, or kidney transplantation. All-cause mortality was verified until December 31, 2011. A counterfactual-framework was applied to estimate the effectiveness of RAAS blockade on outcomes, i.e., ESRD, death before and after ESRD. RAAS blockade was categorized according to duration of use <0.25 year, 0.25-1 year (RAAS1), and >1 year (RAAS2). An augmented inverse-probability weighting (AIPW) method was used to estimate potential-outcome mean (POM) and average treatment-effect (ATE). Multi-logit and Poisson regressions were used for treatment and outcome models, respectively. Analyses were stratified by ESRD, death before/after ESRD for diabetic and non-diabetic groups. STATA 14.0 was used for statistical analyses.

RESULTS

Among 15,032 diabetic patients, 2346 (15.6%), 2351 (18.5%), and 1607 (68.5%) developed ESRD, died before ESRD, and died after ESRD, respectively. Only RAAS2 effect was significant on ESRD, death before and after ESRD. The ESRD rates were 12.9%, versus 20.0% for RAAS2 and non-RAAS, respectively, resulted in significant risk differences (RD) of -7.2% (95% CI: -8.8%, -5.5%), and a numbers needed-to-treat (NNT) of 14. Death rates before ESRD for these corresponding groups were 14.4% (12.9%, 15.9%) and 19.6% (18.7%, 20.4%) with a NNT of 19. Death rates after ESRD in RAAS2 was lower than non-RASS group (i.e., 62.8% (55.5%, 68.9%) versus 68.1% (65.9%, 70.4%)) but this was not significant. RAAS2 effects on ESRD and death before ESRD were persistently significant in non-diabetic patients (n = 17,074) but not for death after ESRD with the NNT of about 15 and 16 respectively.

CONCLUSIONS

Receiving RAAS blockade for 1 year or longer could prevent both CKD progression to ESRD and premature mortality.

Cardiovascular disease risk in patients receiving organ transplantation: a national cohort study

Although organ transplantation is the definitive treatment for end-stage organ failure, the post-transplant outcomes can be substantially influenced by cardiovascular complications. A national cohort study was performed to estimate risks of cardiovascular diseases in those with heart, lung, kidney, and liver transplantation. This cohort study consisted of 5978 solid organ transplantations identified using the Taiwan National Health Insurance Database. Cardiovascular and mortality risks in transplant recipients were evaluated using standardized incidence ratios, excess absolute risks, and standardized mortality ratios as compared to those in the general population. In heart, kidney, and liver recipients, the standardized incidence ratios of overall cardiovascular diseases were 9.41 (7.75-11.44), 3.32 (2.29-3.77), and 1.4 (1.15-1.7) and the overall standardized mortality ratios were 5.23 (4.54-6.03), 1.48 (1.34-1.63), and 3.95 (3.64-4.28), respectively. Except for heart organ recipients who were at highest risk for coronary artery disease with a standardized incidence ratio of 13.12 (10.57-16.29), kidney and liver organ recipients had a ninefold increased risk in developing deep vein thrombosis post-transplant. In conclusion, solid organ transplant patients are at risk of cardiovascular disease, in particular, deep vein thrombosis, which may warrant early identification of high-risk patients in addition to prompt and adequate thromboprophylaxis perioperatively.