Sudden Cardiac Death Among Hemodialysis Patients

Out-of-hospital cardiac arrest in dialysis patients

Purpose

The aim of the study was to assess whether a history of dialysis is related to cardiopulmonary resuscitation (CPR) attempts and survival to hospital admission in patients with out-of-hospital cardiac arrest (OHCA).

Methods

The databases of the POL-OHCA registry and of emergency medical calls in the Command Support System of the State of Emergency Medicine (CSS) were searched to identify patients with OHCA and a history of dialysis. A total of 264 dialysis patient with OHCA were found: 126 were dead on arrival of emergency medical services (EMS), and 138 had OHCA with CPR attempts. Data from the POL-OHCA registry for patients with CPR attempts, including age, sex, place of residence, first recorded rhythm, defibrillation during CPR, and priority dispatch codes, were collected and compared between patients with and without dialysis.

Results

CPR attempts by EMS were undertaken in 138 dialyzed patients (52.3%). The analysis of POL-OHCA data revealed no differences in age, sex, place of residence, first recorded rhythm, and priority dispatch codes between patients with and without dialysis. Defibrillation was less frequent in dialysis patients (P = 0.04). A stepwise logistic regression analysis revealed no association between survival to hospital admission and a history of hemodialysis (odds ratio = 1.12; 95% CI 0.74–1.70, P = 0.60).

Conclusions

A history of dialysis in patients with OHCA does not affect the rate of CPR attempts by EMS or a short-term outcome in comparison with patients without dialysis. Defibrillation during CPR is less common in patients on dialysis than in those without.

Association of hyperphosphatemia with an increased risk of sudden death in patients on hemodialysis: Ten-year outcomes of the Q-Cohort Study

BACKGROUND AND AIMS

Sudden death is one of the most common causes of death among patients on hemodialysis. Although hyperphosphatemia is a well-known risk factor for cardiovascular and all-cause deaths, the studies focusing on the relationship between serum phosphate levels and the risk of sudden death are limited. This study aimed to clarify the relationship between serum phosphate levels and the risk of sudden death in patients on hemodialysis.

METHODS

This is a multicenter, longitudinal, and observational study. A total of 3505 patients, registered in the Q-Cohort Study, who underwent maintenance hemodialysis, and were followed up for 10 years, were included. Patients were divided into quartiles on the basis of baseline serum phosphate levels: Q1 (n = 886), <4.2 mg/dL; Q2 (n = 837), 4.2-4.8 mg/dL; Q3 (n = 908), 4.9-5.6 mg/dL; and Q4 (n = 874), ≥5.7 mg/dL. Associations between baseline serum phosphate levels and sudden death were analyzed using the Cox proportional hazards model and the Fine-Gray regression model.

RESULTS

During the follow-up period, 227 patients died from sudden death. The risk for sudden death was significantly higher in the highest quartile (Q4) than in the lowest quartile (Q1) as the reference group (multivariable-adjusted hazard ratios and 95% confidence intervals: Q1, 1.00; Q2, 1.15 [0.77-1.70], Q3, 1.31 [0.89-1.93], and Q4, 1.72 [1.14-2.59]; hazard ratio for every 1-mg/dL increase in the serum phosphate level, 1.23 [1.09-1.39]; p < 0.001).

CONCLUSIONS

Hyperphosphatemia is independently associated with an elevated risk of sudden death in patients on hemodialysis.

Sudden Cardiac Death in Haemodialysis Patients under Hydroxychloroquine Treatment for COVID-19: A Report of Two Cases

Hydroxychloroquine (HQ) has been used for the treatment of novel coronavirus disease (COVID-19) even though there is no clear evidence for its effectiveness yet. In contrary, HQ has major side effects like QTc prolongation and subsequent development of ventricular arrhythmias. Such side effects may possess additional risks on end-stage renal disease (ESRD) patients who have higher cardiovascular risks than general population. We herein present 2 cases of sudden cardiac death in 2 ESRD patients with COVID-19 for whom a treatment regimen including HQ was preferred. Both patients were clinically stable at the time of arrest. Death could not be attributed to worsening of the COVID-19 since the patients' clinical picture and laboratory values were improving. The cardiac events coincided with the end of routine haemodialysis sessions of both patients. Electrocardiography controls upon admission and on the 24 and 48 h of treatment showed normal QTc intervals. Potential risks contributing to sudden cardiac death during HQ treatment of ESRD patients are discussed.

β-Blocker Use and Risk of Mortality in Heart Failure Patients Initiating Maintenance Dialysis

RATIONAL & OBJECTIVE

Beta-blockers are recommended for patients with heart failure (HF) but their benefit in the dialysis population is uncertain. Beta-blockers are heterogeneous, including with respect to their removal by hemodialysis. We sought to evaluate whether β-blocker use and their dialyzability characteristics were associated with early mortality among patients with chronic kidney disease with HF who transitioned to dialysis.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults patients with chronic kidney disease (aged≥18 years) and HF who initiated either hemodialysis or peritoneal dialysis during January 1, 2007, to June 30, 2016, within an integrated health system were included.

EXPOSURES

Patients were considered treated with β-blockers if they had a quantity of drug dispensed covering the dialysis transition date.

OUTCOMES

All-cause mortality within 6 months and 1 year or hospitalization within 6 months after transition to maintenance dialysis.

ANALYTICAL APPROACH

Inverse probability of treatment weights using propensity scores was used to balance covariates between treatment groups. Cox proportional hazard analysis and logistic regression were used to investigate the association between β-blocker use and study outcomes.

RESULTS

3,503 patients were included in the study. There were 2,115 (60.4%) patients using β-blockers at transition. Compared with nonusers, the HR for all-cause mortality within 6 months was 0.79 (95% CI, 0.65-0.94) among users of any β-blocker and 0.68 (95% CI, 0.53-0.88) among users of metoprolol at transition. There were no observed differences in all-cause or cardiovascular-related hospitalization.

LIMITATIONS

The observational nature of our study could not fully account for residual confounding.

CONCLUSIONS

Beta-blockers were associated with a lower rate of mortality among incident hemodialysis patients with HF. Similar associations were not observed for hospitalizations within the first 6 months following transition to dialysis.

Trends in Use and In-Hospital Outcomes of Subcutaneous Implantable Cardioverter Defibrillators in Patients Undergoing Long-Term Dialysis

BACKGROUND AND OBJECTIVES

Patients on dialysis are at high risk of complications related to implantable cardioverter defibrillator (ICD) implantation; use of subcutaneous ICDs may be preferred over transvenous devices due to lower risk of bloodstream infection and interference with vascular access sites. We evaluated trends in use and in-hospital outcomes of subcutaneous compared with transvenous ICDs among patients on dialysis in the United States.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Retrospective analysis of ICD implants from 2012 to 2018 among patients on dialysis reported to the National Cardiovascular Data Registry ICD Registry, a nationally representative US ICD Registry. We examined overall trends in subcutaneous ICD adoption as a proportion of all eligible ICD implants among patients on dialysis and then compared in-hospital outcomes between eligible subcutaneous ICD and transvenous ICD recipients using inverse probability of treatment weighting.

RESULTS

Of the 23,136 total ICD implants in patients on dialysis during the study period, 3195 (14%) were subcutaneous ICDs. Among eligible first-time ICD recipients on dialysis, the proportion of subcutaneous ICDs used increased yearly from 10% in 2012 to 69% in 2018. In propensity score-weighted analysis of 3327 patients, compared with transvenous ICDs, patients on dialysis receiving subcutaneous ICDs had a higher rate of in-hospital cardiac arrest (2% versus 0.4%, P=0.002), but there was no significant difference in total in-hospital complications (2% versus 1%, P=0.08), all-cause death, or length of hospital stay.

CONCLUSIONS

The utilization of subcutaneous ICDs among US patients on dialysis has been steadily increasing. The overall risk of short-term complications is low and comparable with transvenous ICDs, but higher risks of in-hospital cardiac arrest merits closer monitoring and further investigation.

PODCAST

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Electrophysiological insights into the relationship between calcium dynamics and cardiomyocyte beating function in chronic hemodialysis treatment

For patients in which the Ca²⁺ concentration of dialysis fluid is lower than that in plasma, chronic hemodialysis treatment often leads to cardiac beating dysfunction. By applying these conditions to an electrophysiological mathematical model, we evaluated the impact of body fluid Ca²⁺ dynamics during treatment on cardiomyocyte beating and, moreover, explored measures that may prevent cardiomyocyte beating dysfunction. First, Ca²⁺ concentrations in both plasma and interstitial fluid were decreased with treatment time, which induced both a slight decline in beating rhythm on a sinoatrial nodal cell and a wane in contraction force on a ventricular cell. These simulated results were in agreement with clinical observations. Next, a relationship between the intracellular Ca²⁺ concentration and ion current dynamics of ion transporters were examined to elucidate the mechanism underlying cardiomyocyte beating dysfunction. The inward current of the Na/Ca exchanger (NCX) increased with a decrease in Ca²⁺ concentration in interstitial fluid and induced a reduction in intracellular Ca²⁺ concentration during treatment. Furthermore, the decline in intracellular Ca²⁺ concentration reduced the contraction force. These findings implied that ion transport through the NCX is a dominant factor that induces cardiomyocyte beating dysfunction during hemodialysis. Finally, the replenishment of Ca²⁺ or application of an NCX inhibitor during treatment suppressed the decrease in intracellular Ca²⁺ concentration and contributed to the stabilization of cardiomyocyte beating function. In summary, the clinical implementation of hepatically cleared NCX inhibitor may be a suitable approach to improving the quality of life for patients on chronic hemodialysis.

Trends in Cardiovascular Mortality Among a Cohort of Children and Young Adults Starting Dialysis in 1995 to 2015

IMPORTANCE

Survival of patients receiving dialysis has improved during the last 2 decades. However, few studies have examined temporal trends in the attributed causes of death (especially cardiovascular-related) in young populations.

OBJECTIVE

To determine temporal trends and risk of cause-specific mortality (ie, cardiovascular and infectious) for children and young adults receiving dialysis.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study examined the records of children and young adults (aged <30 years) starting dialysis between 1995 and 2015 according to the United States Renal Data System database. Analyses were performed between June 2019 and June 2020. Fine-Gray models were used to examine trends in risk of different cardiovascular-related deaths. Models were adjusted for age, sex, race, neighborhood income, cause of end-stage kidney disease, insurance type, and comorbidities. Analyses were performed separately for children (ie, age <18 years) and young adults (between ages 18 and 30 years). Follow-up was censored at death or administratively, and transplantation was treated as a competing event.

EXPOSURES

Calendar year.

MAIN OUTCOMES AND MEASURES

Cardiovascular cause-specific mortality.

RESULTS

A total of 80 189 individuals (median [interquartile range] age, 24 [19-28] years; 36 259 [45.2%] female, 29 508 [36.8%] Black, and 15 516 [19.3%] Hispanic white) started dialysis and 16 179 experienced death during a median (interquartile range) of 14.3 (14.0-14.7) years of follow-up. Overall, 40.2% of deaths were from cardiovascular-related causes (6505 of 16 179 patients). In adjusted analysis, risk of cardiovascular-related death was stable initially but became statistically significantly lower after 2006 (vs 1995) in those starting dialysis as either children (subhazard ratio [SHR], 0.74; 95% CI, 0.55-1.00) or adults (SHR, 0.90; 95% CI, 0.83-0.98). Risk of sudden cardiac death improved steadily for all age groups, but to a greater degree in children (SHR, 0.31; 95% CI, 0.20-0.47) vs young adults (SHR, 0.64; 95% CI, 0.56-0.73) comparing 2015 vs 1995. Risk of stroke became statistically significantly lower around 2010 (vs 1995) for children (SHR, 0.40; 95% CI, 0.18-0.88) and young adults (SHR, 0.76; 95% CI, 0.59-0.99).

CONCLUSIONS AND RELEVANCE

In this study, the risk of cardiovascular-related death declined for children and young adults starting dialysis during the last 2 decades, but trends differed depending on age at dialysis initiation and the specific cause of death. Additional studies are needed to improve risk of cardiovascular disease in young populations.

Cardiopulmonary Resuscitation Preferences of People Receiving Dialysis

IMPORTANCE

Whether the cardiopulmonary resuscitation (CPR) preferences of patients receiving dialysis align with their values and other aspects of end-of-life care is not known.

OBJECTIVE

To describe the CPR preferences of patients receiving dialysis and how these preferences are associated with their responses to questions about other aspects of end-of-life care.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional survey study of a consecutive sample of patients receiving dialysis at 31 nonprofit dialysis facilities in 2 US metropolitan areas (Seattle, Washington, and Nashville, Tennessee) between April 22, 2015, and October 2, 2018. Analyses for this article were conducted between December 2018 and April 2020.

EXPOSURES

Participants were asked to respond to the question "If you had to decide right now, would you want CPR if your heart were to stop beating?" Those who indicated they would probably or definitely want CPR were categorized as preferring CPR.

MAIN OUTCOMES AND MEASURES

This study examined the association between preference for CPR and other treatment preferences, engagement in advance care planning, values, desired place of death, expectations about prognosis, symptoms, and palliative care needs.

RESULTS

Of the 1434 individuals invited to complete the survey, 1009 agreed to participate, and 876 were included in the analytic cohort (61.1%). The final cohort had a mean (SD) age of 62.6 (14.0) years; 492 (56.2%) were men, and 528 (60.3%) were White individuals. Among 738 of 876 participants (84.2%) who indicated that they would definitely or probably want CPR (CPR group), 555 (75.2%) wanted mechanical ventilation vs 13 of 138 (9.4%) of those who did not want CPR (do not resuscitate [DNR] group) (P < .001). A total of 249 of 738 participants (33.7%) in the CPR group vs 84 of 138 (60.9%) in the DNR group had documented treatment preferences (P < .001). In terms of values about future care, 171 participants (23.2%) in the CPR group vs 5 of 138 (3.6%) in the DNR group valued life prolongation (P < .001); 320 in the CPR group (43.4%) vs 109 of 138 in the DNR group (79.0%) valued comfort (P < .001); and 247 participants (33.5%) in the CPR group vs 24 of 138 (17.4%) in the DNR group were unsure about their wishes for future care (P < .001). In the CPR group, 207 (28.0%) had thought about stopping dialysis vs 62 of 138 (44.9%) in the DNR group (P < .001), and 181 (24.5%) vs 58 of 138 (42.0%) had discussed stopping dialysis (P = .001). No statistically significant associations were observed between CPR preference and documentation of a surrogate decision maker, thoughts or discussion of hospice, preferred place of death, expectations about prognosis, reported symptoms, or palliative care needs.

CONCLUSIONS AND RELEVANCE

The CPR preferences of patients receiving dialysis were associated with some, but not all, other aspects of end-of-life care. How participants responded to questions about these other aspects of end-of-life care were not always aligned with their CPR preference. More work is needed to integrate discussions about code status with bigger picture conversations about patients' values, goals, and preferences for end-of-life care.

Subjective global assessment of nutrition, dialysis quality, and the theory of the scientific method in Nephrology practice

In an era of evidence-based medicine and dialysis performance measures, there is strong motivation to find specific, objective, quantifiable, and reproducible parameters to characterize the clinical condition of chronic kidney disease patients and to present population-wide statistics that may describe quality of care in dialysis centers. Yet, in the last three decades, several studies demonstrated that while parameters including Kt/V urea, serum phosphorus, parathyroid hormone, serum cholesterol fulfill all these criteria, efforts to optimize these lab parameters failed to improve survival on dialysis. However, subjective assessments of nutrition including subjective global assessment and malnutrition-inflammation score, while not ideally suited for statistical analysis and not optimal from the point of view of scientific methodology due to their general, semi-quantifiable, subjective nature have, nevertheless, proved themselves as some of the strongest predictors of clinical outcomes in the dialysis population. Where does this paradox leave us? We propose that a deeper understanding of relevance of these variables in the dialysis population may improve appreciation of the clinical situation of individual patients and may result in a paradigm shift from dialysis adequacy to quality dialysis.

Use of QT Prolonging Medications by Hemodialysis Patients and Individuals Without End-Stage Kidney Disease

Background The rate of sudden cardiac death in the hemodialysis population exceeds that of the general population by >20-fold. Hemodialysis patients may be particularly susceptible to sudden cardiac death provoked by drug-induced QT prolongation because of their substantial cardiovascular disease burden, exposure to electrolyte shifts during dialysis, and extensive polypharmacy. However, population-specific data regarding the frequency and patterns of QT prolonging medication use are limited. Methods and Results We conducted a descriptive drug utilization study using 3 administrative databases, the United States Renal Data System, MarketScan, and Medicare claims. We characterized the extent and patterns of QT prolonging medication use by adult hemodialysis patients and individuals without end-stage kidney disease annually from 2012 to 2016. We also identified instances of high-risk QT prolonging medication use among hemodialysis patients. In total, 338 515 hemodialysis patients and 40.7 million individuals without end-stage kidney disease were studied. Annual utilization rates of QT prolonging medications with known torsades de pointes risk in hemodialysis patients were ~1.4 to ~2.5 times higher than utilization rates in individuals without end-stage kidney disease. Hemodialysis patients with demographic and clinical risk factors for drug-induced QT prolongation were exposed to medications with known torsades de pointes risk more often than patients without risk factors. Conclusions Hemodialysis patients use QT prolonging medications with known torsades de pointes risk more extensively than individuals without end-stage kidney disease. Given the widespread use and instances of high-risk prescribing, future studies evaluating the cardiac safety of these drugs in the hemodialysis population are needed.

Heart failure management in dialysis patients: Many treatment options with no clear evidence

Heart failure with reduced ejection fraction (HFrEF) impacts approximately 20% of dialysis patients and is associated with high mortality rates. Key issues discussed in this review of HFrEF management in dialysis include dialysis modality choice, vascular access, dialysate composition, pharmacological therapies, and strategies to reduce sudden cardiac death, including the use of cardiac devices. Peritoneal dialysis and more frequent or longer duration of hemodialysis may be better tolerated due to slower ultrafiltration rates, leading to less intradialytic hypotension and better volume control; dialysate cooling and higher dialysate calcium may also have benefits. While high-quality evidence exists for many drug classes in the non-dialysis population, dialysis patients were excluded from major trials, and only limited data exist for many medications in kidney failure patients. Despite limited evidence, beta blocker and angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use is common in dialysis. Similarly, devices such as implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy that have proven benefits in non-dialysis HFrEF patients have not consistently been beneficial in the limited dialysis studies. The use of leadless pacemakers and subcutaneous ICDs can mitigate future hemodialysis access limitations. Additional research is critical to address knowledge gaps in treating maintenance dialysis patients with HFrEF.

A Joint Evaluation of Neurohormone Vasopressin-Neurophysin II-Copeptin and Aortic Arch Calcification on Mortality Risks in Hemodialysis Patients

Objective: Systemic hypoperfusion is intricately involved in neurohormone secretion, vascular calcification (VC) related impaired vasodilation, and luminal stenosis. We aimed to conduct a joint evaluation of vasopressin-neurophysin II-copeptin peptide (VP) and advanced aortic arch calcification (AAC) on all-cause and cardiovascular (CV) mortality in maintenance hemodialysis (MHD) patients. Methods: Unadjusted and adjusted hazard ratios (aHRs) of mortality risks were analyzed for different groups of VP and AAC in 167 MHD patients. The modification effect between higher VP and advanced AAC on mortality risk was examined using an interaction product term. Results: Interactions between VP and AAC with respect to all-cause and CV mortality were statistically significant. In multivariable analysis, higher VP predicted all-cause and CV mortality [aHR: 2.2 (95% confidence interval (CI): 1.1-4.5)] and 2.6 (95% CI: 1.1-4.6), respectively. Advanced AAC was associated with incremental risks of all-cause and CV mortality [aHR: 2.1 (95% CI: 1.1-4.0)and 2.5 (95% CI: 1.0-4.3), respectively]. Patients with combined higher VP (>101.5 ng/mL) and advanced AAC were at the greatest risk of all-cause and CV mortality [aHR: 4.7 (95% CI: 1.2-16.2)and 4.9 (95% CI: 1.1-18.9), respectively]. Conclusion: Combined VP and advanced AAC predict not only all-cause but also CV death in MHD patients, and a joint evaluation is more comprehensive than single marker. In light of hypoperfusion and ischemic events in vital organs, VP and AAC could act as more robust dual marker for prognostic assessment.

In-Hospital Cardiac Arrest Resuscitation Practices and Outcomes in Maintenance Dialysis Patients

BACKGROUND AND OBJECTIVES

Patients on maintenance dialysis with in-hospital cardiac arrest have been reported to have worse outcomes relative to those not on dialysis; however, it is unknown if poor outcomes are related to the quality of resuscitation. Using the Get With The Guidelines-Resuscitation (GWTG-R) registry, we examined processes of care and outcomes of in-hospital cardiac arrest for patients on maintenance dialysis compared with nondialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We used GWTG-R data linked to Centers for Medicare and Medicaid data to identify patients with ESKD receiving maintenance dialysis from 2000 to 2012. We then case-matched adult patients on maintenance dialysis to nondialysis patients in a 1:3 ratio on the basis of age, sex, race, hospital, and year of arrest. Logistic regression models with generalized estimating equations were used to assess the association of in-hospital cardiac arrest and outcomes by dialysis status.

RESULTS

After matching, there were a total of 31,144 GWTG-R patients from 372 sites, of which 8498 (27%) were on maintenance dialysis. Patients on maintenance dialysis were less likely to have a shockable initial rhythm (20% versus 21%) and less likely to be within the intensive care unit at the time of arrest (46% versus 47%) compared with nondialysis patients; they also had lower composite scores for resuscitation quality (89% versus 90%) and were less likely to have defibrillation within 2 minutes (54% versus 58%). After adjustment, patients on maintenance dialysis had similar adjusted odds of survival to discharge (odds ratio [OR], 1.05; 95% confidence interval [95% CI], 0.97 to 1.13), better acute survival (OR, 1.33; 95% CI, 1.26 to 1.40), and were more likely to have favorable neurologic status (OR, 1.12; 95% CI, 1.04 to 1.22) compared with nondialysis patients.

CONCLUSIONS

Although there appears to be opportunities to improve the quality of in-hospital cardiac arrest care for among those on maintenance dialysis, survival to discharge was similar for these patients compared with nondialysis patients.

Dialysis modality-related disparities in sudden cardiac death: hemodialysis versus peritoneal dialysis

Background

Patients require risk stratification and preventive strategies for sudden cardiac death (SCD) based on the dialysis modality because the process of dialysis is a risk factor for SCD. This study aimed to compare the risk of SCD in patients undergoing hemodialysis (HD) versus peritoneal dialysis (PD).

Methods

Patients on HD and PD were included in the end-stage renal disease registry of the Korean Society of Nephrology between 1985 and 2017. The incidence and associated factors of SCD were analyzed based on the dialysis modality.

Results

Of 132,083 patients, 34,632 (26.2%) died during 94.8 ± 73.6 months of follow-up. In patients on HD and PD, 22.2% and 19.6% of total deaths were SCDs. In the propensity score-matched population, SCD accounted for 21.7% and 19.6% of total deaths in patients on HD and PD, respectively. HD was independently associated with SCD even after adjusting for age and significant comorbidities. Hypertension, coronary artery disease, and congestive heart failure, and age at the time of death < 65 years were independent risk factors for SCD in patients on HD but not in those on PD. Diabetes was significantly associated with SCD regardless of the dialysis modality.

Conclusion

Compared with patients on PD, Korean patients on HD have a higher risk of SCD, which is attributable to cardiac comorbidities.

Hypocalcemia-Induced Slowing of Human Sinus Node Pacemaking

Each heartbeat is initiated by cyclic spontaneous depolarization of cardiomyocytes in the sinus node forming the primary natural pacemaker. In patients with end-stage renal disease undergoing hemodialysis, it was recently shown that the heart rate drops to very low values before they suffer from sudden cardiac death with an unexplained high incidence. We hypothesize that the electrolyte changes commonly occurring in these patients affect sinus node beating rate and could be responsible for severe bradycardia. To test this hypothesis, we extended the Fabbri et al. computational model of human sinus node cells to account for the dynamic intracellular balance of ion concentrations. Using this model, we systematically tested the effect of altered extracellular potassium, calcium, and sodium concentrations. Although sodium changes had negligible (0.15 bpm/mM) and potassium changes mild effects (8 bpm/mM), calcium changes markedly affected the beating rate (46 bpm/mM ionized calcium without autonomic control). This pronounced bradycardic effect of hypocalcemia was mediated primarily by ICaL attenuation due to reduced driving force, particularly during late depolarization. This, in turn, caused secondary reduction of calcium concentration in the intracellular compartments and subsequent attenuation of inward INaCa and reduction of intracellular sodium. Our in silico findings are complemented and substantiated by an empirical database study comprising 22,501 pairs of blood samples and in vivo heart rate measurements in hemodialysis patients and healthy individuals. A reduction of extracellular calcium was correlated with a decrease of heartrate by 9.9 bpm/mM total serum calcium (p < 0.001) with intact autonomic control in the cross-sectional population. In conclusion, we present mechanistic in silico and empirical in vivo data supporting the so far neglected but experimentally testable and potentially important mechanism of hypocalcemia-induced bradycardia and asystole, potentially responsible for the highly increased and so far unexplained risk of sudden cardiac death in the hemodialysis patient population.

A simple modification of dialysate potassium: its impact on plasma potassium concentrations and the electrocardiogram

Background

Sudden death is frequent in haemodialysis (HD) patients. Both hyperkalaemia and change of plasma potassium (K) concentrations induced by HD could explain this. The impact of increasing dialysate K by 1 mEq/L on plasma K concentrations and electrocardiogram (ECG) results before and after HD sessions was studied.

Methods

Patients with pre-dialysis K >5.5 mEq/L were excluded. ECG and K measurements were obtained before and after the first session of the week for 2 weeks. Then, K in the dialysate was increased (from 1 or 3 to 2 or 4 mEq/L, respectively). Blood and ECG measurements were repeated after 2 weeks of this change.

Results

Twenty-seven prevalent HD patients were included. As expected, a significant decrease in K concentrations was observed after the dialysis session, but this decrease was significantly lower after the switch to an increased dialysate K. The pre-dialysis K concentrations were not different after changing, but post-dialysis K concentrations were higher after switching (P < 0.0001), with a lower incidence of post-dialysis hypokalaemia. Regarding ECG, before switching, the QT interval (QT) dispersion increased during the session, whereas no difference was observed after switching. One week after switching, post-dialysis QT dispersion [38 (34-42) ms] was lower than post-dialysis QT dispersion 2 weeks and 1 week before switching [42 (38-57) ms, P = 0.0004; and 40 (35-50) ms, P = 0.0002].

Conclusions

A simple increase of 1 mEq/L of K in the dialysate is associated with a lower risk of hypokalaemia and a lower QT dispersion after the dialysis session. Further study is needed to determine if such a strategy is associated with a lower risk of sudden death.

Valvular Calcification in Chronic Kidney Disease

Accelerated and premature cardiovascular calcification is a hallmark of patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD). The presence and the amount of cardiovascular calcification are among the driving forces of increased morbidity and mortality in renal patients. Cardiovascular calcification occurs at different sites, including the cardiac valves-a location that is of particular importance for both the patient and the treating physician. The correlation between degree of calcification and functional impairment is particularly close at the aortic valve, that is, the amount of calcification predicts the degree of stenosis. Calcific aortic stenosis (CAS) is the most prevalent valvular heart disease in Western societies. CAS is particularly prevalent in patients with underlying CKD or ESRD. CAS increases afterload and hence contributes to the widespread finding of left ventricular hypertrophy in CKD/ESRD patients. Medical treatment options to prevent the development and progression of CAS are limited. Hence, close surveillance and timely referral of patients for heart valve replacement therapy is a mainstay of current therapy. Novel treatment approaches, such as transcatheter aortic valve implantation, offer promising yet challenging options for elderly, comorbid, and often frail patients with CAS in combination with advanced CKD/ESRD.

Impending challenges of the burden of end-stage kidney disease in Australia

Sex and age-specific incidence rates of patients with treated end-stage kidney disease (ESKD) in Australia are comparable to those in European countries, but substantially lower compared with those in the United States, Canada and many Asian countries. The incidence rates of treated ESKD in Australia increase with advancing age; however, the incidence of ESKD is likely to be underestimated because a proportion of patients with ESKD (about 50%) remain untreated. Late referral to nephrologists has reduced over the past decade, temporally associated with improved ESKD recognition. However, late referral still occurs in one in five Australians with ESKD. One in two Australians with ESKD has diabetes, with up to 35% of cases directly attributed to diabetes. Mortality rates for patients with ESKD remain substantially higher compared with the age-matched general population, although there has been a significant improvement in survival over time. Cardiovascular disease and cancer are the two most common causes of death in patients with ESKD.

Hemodialysis Procedure-Associated Autonomic Imbalance and Cardiac Arrhythmias: Insights From Continuous 14-Day ECG Monitoring

Background

In patients with end‐stage kidney disease, sudden cardiac death is more frequent after a long interdialytic interval, within 6 hours after the end of a hemodialysis session. We hypothesized that the occurrence of paroxysmal arrhythmias is associated with changes in heart rate and heart rate variability in different phases of hemodialysis.

Methods and Results

We conducted a prospective ancillary study of the Predictors of Arrhythmic and Cardiovascular Risk in End Stage Renal Disease cohort. Continuous ECG monitoring was performed using an ECG patch, and short‐term heart rate variability was measured for 3 minutes every hour (by root mean square of the successive normal‐to‐normal intervals, spectral analysis, Poincaré plot, and entropy), up to 300 hours. Out of enrolled participants (n=28; age 54±13 years; 57% men; 96% black; 33% with a history of cardiovascular disease; left ventricular ejection fraction 70±9%), arrhythmias were detected in 13 (46%). Nonsustained ventricular tachycardia occurred more frequently during/posthemodialysis than pre‐/between hemodialysis (63% versus 37%, P=0.015). In adjusted for cardiovascular disease time‐series analysis, nonsustained ventricular tachycardia was preceded by a sudden heart rate increase (by 11.2 [95% CI 10.1–12.3] beats per minute; P<0.0001). During every‐other‐day dialysis, root mean square of the successive normal‐to‐normal intervals had a significant circadian pattern (Mesor 10.6 [ 95% CI 0.9–11.2] ms; amplitude 1.5 [95% CI 1.0–3.1] ms; peak at 02:01 [95% CI 20:22–03:16] am; P<0.0001), which was replaced by a steady worsening on the second day without dialysis (root mean square of the successive normal‐to‐normal intervals −1.41 [95% CI −1.67 to −1.15] ms/24 h; P<0.0001).

Conclusions

Sudden increase in heart rate during/posthemodialysis is associated with nonsustained ventricular tachycardia. Every‐other‐day hemodialysis preserves circadian rhythm, but a second day without dialysis is characterized by parasympathetic withdrawal.

The Incidence and Associated Factors of Sudden Death in Patients on Hemodialysis: 10-Year Outcome of the Q-Cohort Study

Aim: The incidence of sudden death and its risk factors in patients on hemodialysis remain unclear. This study aimed to clarify the incidence of sudden death and its risk factors in Japanese patients on hemodialysis.

Methods: A total of 3505 patients on hemodialysis aged ≥ 18 years were followed for 10 years. Multivariate-adjusted hazard ratio (HR) with 95% confidence interval (95% CI) of each risk factor of sudden death were calculated using a Cox proportional hazards model.

Results: During the 10-year follow-up, 1735 patients died, including 227 (13%) sudden deaths. The incidence rate of sudden death was 9.13 per 1000 person-years. In multivariable-adjusted Cox analysis, male sex (HR 1.67; 95% CI 1.20–2.33), age (HR 1.44; 95% CI 1.26–1.65 per 10-year higher), the presence of diabetes (HR 2.45; 95% CI 1.82–3.29), history of cardiovascular disease (HR 1.85; 95% CI 1.38–2.46), cardiothoracic ratio (HR 1.21; 95% CI 1.07–1.39 per 5% higher), serum C-reactive protein (HR 1.11; 95% CI 1.03–1.20 per 1-mg/dL higher), and serum phosphate (HR 1.15; 95% CI 1.03–1.30 per 1-mg/dL higher) were independent predictors of sudden death. A subgroup analysis stratified by sex or age showed that lower serum corrected calcium levels, not using vitamin D receptor activators in women, and a shorter dialysis session length in men or older people (≥ 65 years) increased the risk for sudden death.

Conclusions: This study clarified the incidence of sudden death and its specific predictors in Japanese patients on hemodialysis.

Sudden Cardiac Death in End-Stage Renal Disease

The challenge presented by sudden cardiac death in dialysis patients is to better define risk factors and delineate multiple etiologies. Only then can therapy be tailored to the highest risk patients and the incidence of sudden cardiac death be reduced. This article details the many possible etiologies and presents a brief overview of more recent research that may in the future prove of great benefit in improving the mortality of our patients with end-stage renal disease.

Microfluidic DNA-based potassium nanosensors for improved dialysis treatment

BACKGROUND

Patients with end-stage renal disease (ESRD) have failed kidney function, and often must be treated with hemodialysis to extend the patient's life by artificially removing excess fluid and toxins from the blood. However, life-threatening treatment complications can occur because hemodialysis protocols are adjusted infrequently, as opposed to the kidneys which filter blood continuously. Infrequent blood tests, about once per month on average, are used to adjust hemodialysis protocols and as a result, patients can experience electrolyte imbalances, which can contribute to premature patient deaths from treatment complications, such as sudden cardiac death. Since hemodialysis can lead to blood loss, drawing additional blood for tests to assess the patient's kidney function and blood markers is limited. However, sampling multiple drops of blood per session using a microfluidic device has the potential to reduce not only the amount of blood drawn and avoid unnecessary venipuncture, but also reduce costs by limiting medical complications of hemodialysis and provide a more comprehensive assessment of the patient's health status in real time.

RESULT

We present preliminary proof-of-concept results of a microfluidic device which uses DNA-based fluorescence nanosensors to measure potassium concentration in a flowing solution. In a matter of minutes, the flowing potassium solution reduced the fluorescence intensity of the nanosensors to a steady-state value.

CONCLUSIONS

These proof-of-concept results demonstrate the ability of our DNA-based nanosensors to measure potassium concentration in a microfluidic device. The long-term goal is to integrate this technology with a device to measure potassium and eventually other blood contents multiple times throughout a hemodialysis session, enabling protocol adjustment similar to a healthy kidney.

Drug-eluting compared to bare metal stents in patients with end-stage renal disease on dialysis: a meta-analysis

AIMS

To systematically review literature comparing bare metal stent (BMS) to drug-eluting stent (DES) in end-stage renal disease (ESRD) patients on dialysis. ESRD patients on dialysis often suffer from accelerated atherosclerosis and higher rate of stent-related complications including major adverse cardiovascular events. Because dialysis usually qualifies ineligibility for randomized clinical trials, an evidenced-based stent choice for these patients is scarce.

METHODS

PUBMED, CINHAL, COCHRANE, EMBASE and WEB OF SCIENCE were searched for studies comparing BMS vs. DES outcome in ESRD patients on dialysis.

RESULTS

Twenty studies including 64 232 patients were considered. The use of DES was significantly associated with a reduction in all-cause mortality [odds ratio (OR) 0.83, 95% confidence interval (CI) 0.76-0.89], death from a cardiovascular cause (OR 0.80, 95% CI 0.76-0.84) and target lesion revascularization/target vessel revascularization (OR 0.73, 95% CI 0.53-1.00). No significant difference was found in stent thrombosis (OR 1.08, 95% CI 0.50-2.33) and myocardial infarction incidence (OR 0.91, 95% CI 0.69-1.20).

CONCLUSIONS

Our meta-analysis shows a significant reduction in all-cause and cardiovascular mortality with the use of DES over BMS in dialyzed patients. Despite the lack of randomized studies, systematic use of DES in these high-risk patients should thus reasonably be considered as a first option in percutaneous coronary intervention candidates.

Risk Stratification and Treatment of Coronary Disease in Chronic Kidney Disease and End-Stage Kidney Disease

Patients with advanced chronic kidney disease have an enormous burden of cardiovascular morbidity and mortality, but, paradoxically, their representation in randomized trials for the evaluation and management of coronary artery disease has been limited. Clinicians therefore are faced with the conundrum of synergizing evidence from observational studies, expert opinion, and extrapolation from the general population to provide care to this complex and clinically distinct patient population. In this review, we address clinical risk stratification of patients with chronic kidney disease and end-stage kidney disease using traditional cardiovascular risk factors, noninvasive functional and structural cardiac imaging, invasive coronary angiography, and cardiovascular biomarkers. We highlight the unique characteristics of this population, including the high competing risk of all-cause mortality relative to the risk of major adverse cardiac events, likely owing to important contributions from nonatherosclerotic mechanisms. We further discuss the management of coronary artery disease in patients with chronic kidney disease and end-stage kidney disease, including evidence pertaining to medical management, coronary revascularization with percutaneous coronary intervention, and coronary artery bypass grafting. Our discussion includes considerations of drug-eluting versus bare metal stents for percutaneous coronary intervention and off-pump versus on-pump coronary artery bypass graft surgery. Finally, we address currently ongoing randomized trials, from which clinicians are optimistic about receiving guidance regarding the best strategies to incorporate into their practice for the evaluation and management of coronary artery disease in this high-risk population.

Dialysis Prescription and Sudden Death

In the United States, end-stage renal disease patients receiving hemodialysis have an exceedingly high risk of sudden cardiac death (SCD), accounting for 29% of death events, likely relating to their uremic milieu, recurring exposure to fluid and electrolyte fluxes, and underlying cardiovascular pathology. Furthermore, epidemiologic studies have shown that SCD events, as well as mortality and hospitalizations, occur most frequently on the first dialysis day after the long interdialytic gap, suggesting that abrupt fluctuations in the accumulation and removal of electrolytes, fluid, and uremic toxins over the dialysis cycle may be contributory. Some population-based observational studies have suggested that lower dialysate potassium concentrations appear to be associated with a heightened risk of postdialysis cardiac arrest in hemodialysis patients, although the optimal serum-to-dialysate potassium gradient remains unclear. Some observational studies have suggested that low dialysate calcium concentrations and high serum-to-dialysate calcium gradients may predispose patients to SCD. There is ongoing controversy about an association between higher dialysate bicarbonate concentrations and higher risk of cardiac arrest, likely owing to confounding by indication. Some observational studies also have shown that large interdialytic weight gains, fluid retention, and high ultrafiltration rates are linked with higher risk of SCD and mortality. However, there remains considerable controversy regarding the pros and cons of designating a specific upper ultrafiltration limit with extended treatment times as a clinical practice measure, and further studies are needed to define the optimal tools, metrics, targets, and implementation measures for volume control in the hemodialysis population. In this review, we highlight the epidemiology and pathophysiology of how specific aspects of the hemodialysis procedure may relate to the risk of SCD, as well as preventative strategies and future research directions that can address this risk.

Blood Pressure Pattern and Target Organ Damage in Patients With Chronic Kidney Disease

In patients with chronic kidney disease, data on blood pressure (BP) pattern and its association with target organ damage, which indicates elevated cardiovascular risk, are sparse. In 305 treated hypertensive chronic kidney disease patients, we assessed BP pattern, left ventricular mass (magnetic resonance imaging), intima-media thickness (ultrasound), 24-hour-pulse wave velocity and 24-hour-central augmentation index (Mobil-O-Graph). Controlled hypertension (normal office and ambulatory BP) was found in 41% and sustained uncontrolled hypertension (elevated office and ambulatory BP) in 30% of patients. Misclassification of BP status occurred in 29%: white coat uncontrolled hypertension (elevated office but normal ambulatory BP) was detected in 11% and masked uncontrolled hypertension (normal office but elevated ambulatory BP) in 18% of patients. Left ventricular mass was increased in white coat uncontrolled hypertension (+11.2 g), masked uncontrolled hypertension (+9.4 g), and sustained uncontrolled hypertension (+16.6 g) compared with controlled hypertension. Intima-media thickness was similar across all 4 BP groups. Twenty-four hour-pulse wave velocity and 24-hour-central augmentation index were increased in masked uncontrolled hypertension (+0.5 m/sec and +2.5%) and sustained uncontrolled hypertension (+0.5 m/sec and +2.9%) compared with controlled hypertension. In conclusion, based on office BP measurements, misclassification of true BP status occurred in almost one-third of chronic kidney disease patients. Both types of misclassification (white coat uncontrolled hypertension and masked uncontrolled hypertension) were associated with parameters of target organ damage. Ambulatory BP monitoring should be used routinely to identify chronic kidney disease patients at high cardiovascular risk.

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.

Outcomes for Hemodialysis Patients Given Cardiopulmonary Resuscitation for Cardiac Arrest at Outpatient Dialysis Clinics

BACKGROUND

Out-of-hospital cardiac arrest, the leading cause of death among patients on hemodialysis, occurs frequently within outpatient dialysis centers. Practice guidelines recommend resuscitation training for all dialysis clinic staff and on-site defibrillator availability, but the extent of staff involvement in cardiopulmonary resuscitation (CPR) efforts and its association with outcomes is unknown.

METHODS

We used data from the Cardiac Arrest Registry to Enhance Survival and the Centers for Medicare & Medicaid Services dialysis facility database to identify patients who had cardiac arrest within outpatient dialysis clinics between 2010 and 2016 in the southeastern United States. We compared outcomes of patients who received dialysis staff-initiated CPR with those who did not until the arrival of emergency medical services (EMS).

RESULTS

Among 398 OHCA events in dialysis clinics, 66% of all patients presented with a nonshockable initial rhythm. Dialysis staff initiated CPR in 81.4% of events and applied defibrillators before EMS arrival in 52.3%. Staff were more likely to initiate CPR among men and witness cardiac arrests, and were more likely to provide CPR within larger dialysis clinics. Staff-initiated CPR was associated with a three-fold increase in the odds of hospital discharge and favorable neurologic status on discharge. There was no overall association between staff-initiated defibrillator use and outcomes, but there was a nonsignificant trend toward improved survival to hospital discharge in the subgroup with shockable initial cardiac arrest rhythms.

CONCLUSIONS

Dialysis staff-initiated CPR was associated with a large increase in survival but was only performed in 81% of cardiac arrest events. Further investigations should focus on understanding the potential facilitators and barriers to CPR in the dialysis setting.

Arterial Stiffness in CKD: A Review

This narrative review summarizes a decade of experience examining the cross-sectional and longitudinal relationships of arterial stiffness, as assessed using carotid-femoral pulse wave velocity, with outcomes in patients with chronic kidney disease enrolled in the Chronic Renal Insufficiency Cohort. Our goal is to review the importance of the pulse wave contour and pulse wave velocity and present data on the reproducibility of pulse wave velocity measurements, determinants of pulse wave velocity, and the relationship that velocity measurements have with longitudinal kidney and cardiovascular outcomes. Measures of arterial stiffness have contributed substantially to our understanding of mechanisms of cardiovascular disease, kidney disease progression, and all-cause mortality. Given the independent relationship of arterial stiffness to a variety of outcomes, it is our hope that future developments in behavioral, nutritional, and pharmacologic approaches to vascular destiffening will provide interventions that benefit patients with chronic kidney diseases.

A randomized controlled trial of the effect of spironolactone on left ventricular mass in hemodialysis patients

Mineralocorticoid receptor antagonists have beneficial effects on left ventricular remodeling, cardiac fibrosis, and arrhythmia in heart failure, but efficacy and safety in dialysis patients is less clear. We evaluated the effect of spironolactone on left ventricular mass (LVM), an independent predictor of all-cause and cardiovascular mortality, in hemodialysis patients. In this placebo-controlled, parallel-group trial, 97 hemodialysis patients (23% female; mean age 60.3 years) were randomized to spironolactone 50 mg once daily (n=50) or placebo (n=47). The primary efficacy endpoint was change in LVM index (LVMi) from baseline to 40 weeks as determined by cardiac magnetic resonance imaging. Safety endpoints were development of hyperkalemia and change in residual renal function. There was no significant change in LVMi in participants randomized to spironolactone compared to placebo (-2.86±11.87 vs. 0.41±10.84 g/m²). There was also no difference in the secondary outcomes of mean 24-hour systolic or diastolic ambulatory blood pressure, left ventricular ejection fraction, 6-minute walk test distance, or New York Heart Association functional class. Moderate hyperkalemia (pre-dialysis potassium levels of 6.0-6.5 mmol/L) was more frequent with spironolactone treatment (155 vs. 80 events), but severe hyperkalemia (≥6.5 mmol/L) was not (14 vs. 24 events). Changes in residual urine volume and measured glomerular filtration rate did not differ between groups. There were no deaths in the spironolactone group and 4 deaths in the placebo group. Thus, treatment with 50 mg spironolactone did not change left ventricular mass index, cardiac function, or blood pressure in hemodialysis patients. Spironolactone increased the frequency of moderate hyperkalemia, but did not increase severe hyperkalemia.

Effect of Hemodialysis on Corrected QT Interval and QTc Dispersion

Hemodialysis patients are at higher risk of cardiovascular disease due to traditional and dialysis-related risk factors. Our aim was to study the effects of hemodialysis on the corrected QT interval (QTc) and QTc dispersion in chronic kidney disease (CKD) without clinically manifest heart disease. Two hundred cases of CKD on chronic intermittent hemodialysis of >3 months' duration were included in the study. Twelve-lead electrocardiography and samples for serum creatinine, potassium, calcium, and magnesium were taken before and after dialysis. The mean age of patients was 52.4 ± 17 years with male-to-female ratio of 3:1. QTc interval and QTc dispersion were prolonged in 47% and 59% before and 50% and 89% of patients after hemodialysis, respectively. The mean values of QTc were 433.4 ± 36.9 ms before and 451.4 ± 39.6 ms after hemodialysis (p = 0.001) and the mean values of QTc dispersion were 60.5 ± 19.3 ms before and 81.5 ± 24.4 ms after hemodialysis (p = 0.001). Similar pattern was observed in all etiological groups of CKD, except for QTc dispersion in malignancy-related CKD (p = 0.216). After hemodialysis, there was a significant fall in the mean values of serum potassium (p = 0.001), rise in serum calcium (p = 0.001), and no change in magnesium (p = 0.424). Patients with post hemodialysis QTc dispersion >74 ms had significantly low mean values of serum potassium and calcium as compared to <74 ms group. Large numbers of hemodialysis patients have a prolonged QTc interval and QTc dispersion with a significant increase in the mean values after hemodialysis. There is a significant fall in serum potassium and rise in serum calcium after dialysis.

Sofosbuvir Based Regimen in Management of Hepatitis C for Patients With End Stage Renal Disease on Hemodialysis: A Single Center Experience from India

BACKGROUND

Hepatitis C infection is known to increase the morbidity in patients with end stage renal disease (ESRD). Interferon based treatment is poorly tolerated and has limited cure rates in these patients. In limited available data, sofosbuvir based regimens have been shown to have favorable outcomes in these patients.

METHODS

We treated 7 patients with ESRD on hemodialysis, 6 with chronic hepatitis C and one with acute hepatitis C. Two of them were cirrhotic of which one was decompensated. All patients were treated with sofosbuvir 200 mg with daclatasvir 60 mg or ribavirin 200 mg once daily. Patients with evidence of cirrhosis were treated for 24 weeks, others were treated for 12 weeks. HCV RNA quantitative PCR was monitored at weeks 2, 4, 12, end of therapy and after 12 weeks of end of treatment (SVR12).

RESULTS

The study cohort included five males and two females, aged (48.4 ± 14.5 years). Four patients had genotype 1 and three had genotype 3. One patient was treated with sofosbuvir and ribavirin while others were treated with sofosbuvir and daclatasvir. One patient died of unrelated cause during the therapy. One patient who received sofosbuvir and daclatasvir, could not complete the therapy beyond 20 weeks because she developed recurrent hypoglycemia, which improved after stopping the therapy, all the other patients had SVR 12. There was no change in Hb levels or erythropoietin requirement in the patients receiving sofosbuvir and daclatasvir.

CONCLUSION

Our data suggest that sofosbuvir based therapy is effective in patients with ESRD and hepatitis C, including those with liver cirrhosis. Its use may be recommended especially in countries where other drugs are not available. Due to limited experience however, patients should be closely monitored for adverse effects. Hypoglycemia may be a potential adverse effect of sofosbuvir and daclatasvir therapy.

Safety of Low-calcium Dialysate and its Effects on Coronary Artery Calcification in Patients Undergoing Maintenance Hemodialysis

To determine the safety of low-calcium-dialysate in patients undergoing maintenance hemodialysis (MHD) and its effects on coronary artery calcification (CAC) and analyze clinical risk factors for CAC. A total of 174 MHD patients were recruited and randomly divided into two groups: high-calcium dialysate (HCD, 1.5 mmol/L Ca²⁺) and low-calcium dialysate (LCD, 1.25 mmol/L Ca²⁺). Changes in CAC score (CACS) and cardiac function were evaluated using spiral computed tomography and echocardiography, respectively. Clinical and laboratory parameters were measured. Intra-dialysis adverse reactions were recorded and compared between the two groups. CACS was significantly lower in the LCD group than in the HCD group by the end of the study. Cardiac E/A_max was significantly higher in the LCD group than in the HCD group by the end of the study. There was no significant difference in the frequency of any intra-dialysis adverse reactions between the two groups during the study. LCD is helpful in maintaining cardiac diastolic function and postponing CAC progression. LCD does not increase intra-dialysis adverse reactions. Age may be the most important factor impacting CAC in MHD patients.

Health service utilisation during the last year of life: a prospective, longitudinal study of the pathways of patients with chronic kidney disease stages 3-5

Background

Chronic kidney disease (CKD) is a growing global problem affecting around 10% of many countries’ populations. Providing appropriate palliative care services (PCS) to those with advanced kidney disease is becoming paramount. Palliative/supportive care alongside usual CKD clinical treatment is gaining acceptance in nephrology services although the collaboration with and use of PCS is not consistent.

Methods

The goal of this study was to track and quantify the health service utilisation of people with CKD stages 3-5 over the last 12 months of life. Patients were recruited from a kidney health service (Queensland, Australia) for this prospective, longitudinal study. Data were collected for 12 months (or until death, whichever was sooner) during 2015-17 from administrative health sources. Emergency department presentations (EDP) and inpatient admissions (IPA) (collectively referred to as critical events) were reviewed by two Nephrologists to gauge if the events were avoidable.

Results

Participants (n = 19) with a median age of 78 years (range 42-90), were mostly male (63%), 79% had CKD stage 5, and were heavy users of health services during the study period. Fifteen patients (79%) collectively recorded 44 EDP; 61% occurred after-hours, 91% were triaged as imminently and potentially life-threatening and 73% were admitted. Seventy-four IPA were collectively recorded across 16 patients (84%); 14% occurred on weekends or public holidays. Median length of stay was 3 days (range 1-29). The median number of EDP and IPA per patient was 1 and 2 (range 0-12 and 0-20) respectively. The most common trigger to both EDP (30%) and IPA (15%) was respiratory distress. By study end 37% of patients died, 63% were known to PCS and 11% rejected a referral to a PCS. All critical events were deemed unavoidable.

Conclusions

Few patients avoided using acute health care services in a 12 month period, highlighting the high service needs of this cohort throughout the long, slow decline of CKD. Proactive end-of-life care earlier in the disease trajectory through integrating renal and palliative care teams may avoid acute presentations to hospital through better symptom management and planned care pathways.

Frequency of arrhythmia symptoms and acceptability of implantable cardiac monitors in Hemodialysis patients

Background

Arrhythmia-related complications and sudden death are common in dialysis patients. However, routine cardiac monitoring has so far not been feasible. Miniaturization of implantable cardiac monitors offers a new paradigm for detection and management of arrhythmias in dialysis patients. The goal of our study was to determine the frequency of arrhythmia-related symptoms in hemodialysis patients and to assess their willingness to undergo implantation of a cardiac monitor.

Methods

We conducted a survey of in-center hemodialysis patients at a hemodialysis clinic in Baltimore, Maryland. We assessed the frequency of arrhythmia-related symptoms and willingness to undergo placement of an implantable cardiac monitor (LINQ, Medtronic Inc.).

Results

Forty six patients completed the survey. The mean age of the survey respondents was 59 years and 65% were male. Symptoms were common with 74% (n = 34) of participants reporting at least one arrhythmia-related symptom and many [22% (n = 10)] had all 3 symptoms. Among the patients with symptoms, 57% (n = 26) reported “heart skipping beats, flopping in chest or beating very hard,” 61% (n = 28) reported “heart racing (palpitations),” and 37% (n = 17) reported feeling that they “passed out or almost passed out.” The majority of the patients felt that the timing of the symptoms was unrelated to dialysis treatments. The acceptability of the monitoring device implantation was high, with 59% (n = 20) of patients with symptoms and 50% (n = 6) of patients without symptoms willing to consider it. The main reason for not considering the device was not wanting to have an implanted device.

Conclusion

The prevalence of arrhythmia-related symptoms is high in hemodialysis patients and the majority would consider an implantable cardiac monitor if recommended by their physicians. Routine implantation of cardiac monitoring devices to manage arrhythmias in dialysis patients may be feasible and will provide further insights on the leading causes of morbidity and mortality in dialysis patients.

Electronic supplementary material

The online version of this article (10.1186/s12882-017-0740-1) contains supplementary material, which is available to authorized users.

Sign and magnitude scaling properties of heart rate variability in patients with end-stage renal failure: Are these properties useful to identify pathophysiological adaptations?

The scaling properties of heart rate variability data are reliable dynamical features to predict mortality and for the assessment of cardiovascular risk. The aim of this manuscript was to determine if the scaling properties, as provided by the sign and magnitude analysis, can be used to differentiate between pathological changes and those adaptations basically introduced by modifications of the mean heart rate in distinct manoeuvres (active standing or hemodialysis treatment, HD), as well as clinical conditions (end stage renal disease, ESRD). We found that in response to active standing, the short-term scaling index (α₁) increased in healthy subjects and in ESRD patients only after HD. The sign short-term scaling exponent (α_1sign) increased in healthy subjects and ESRD patients, showing a less anticorrelated behavior in active standing. Both α₁ and α_1sign did show covariance with the mean heart rate in healthy subjects, while in ESRD patients, this covariance was observed only after HD. A reliable estimation of the magnitude short-term scaling exponent (α_1magn) required the analysis of time series with a large number of samples (>3000 data points). This exponent was similar for both groups and conditions and did not show covariance with the mean heart rate. A surrogate analysis confirmed the presence of multifractal properties (α_1magn > 0.5) in the time series of healthy subjects and ESDR patients. In conclusion, α₁ and α_1sign provided insights into the physiological adaptations during active standing, which revealed a transitory impairment before HD in ESRD patients. The presence of multifractal properties indicated that a reduced short-term variability does not necessarily imply a declined regulatory complexity in these patients.