Effect of henagliflozin on left ventricular mass index in dialysis patients with HFpEF (HELD-HF): protocol for a multicentre, randomised, double-blind, placebo-controlled trial

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) is a prevalent comorbidity among patients with end-stage kidney disease. Although sodium-glucose cotransporter 2 inhibitors are validated in treating heart failure and ameliorating left ventricular hypertrophy among non-dialysis patients, the effects on dialysis patients are unknown. We previously investigated the pharmacokinetics of henagliflozin in patients undergoing haemodialysis (HD) or peritoneal dialysis (PD) and clarified its safety.

METHODS AND ANALYSIS

This multicentre, randomised, double-blind, placebo-controlled trial is being conducted at three hospitals in Shanghai, China. A target of 108 HD or PD patients with HFpEF are randomly allocated to treatment group (henagliflozin 5 mg/day in addition to standard therapy) or control group (placebo with standard therapy) at a ratio of 1:1. All subjects will be followed up for 24 weeks. The primary outcome is change in echocardiography-measured left ventricular mass index. The secondary interests include changes in left atrial volume index, E/e', e' and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Intergroup comparisons of change in echocardiography-related outcomes from baseline to 24 weeks are based on a linear regression model adjusted for baseline values (analysis of covariance), and repeated measure analysis of variance with Bonferroni adjustment is employed for comparison of change in NT-proBNP. Subgroup analyses of the primary and secondary outcomes are conducted to determine whether the effect of henagliflozin varies according to dialysis modality. The χ2 method is used to compare the occurrence of adverse events and severe adverse events.

ETHICS AND DISSEMINATION

This trial has been approved by the Ethics Committee of Renji Hospital, School of Medicine, Shanghai Jiao Tong University (LY2023-127-B). All participants provide written informed consent before screening. The results of the trial will be disclosed completely in international peer-reviewed journals. Both positive and negative results will be reported.

TRIAL REGISTRATION NUMBER

ChiCTR2300073169.

Application of DSM–BIA in dry weight assessment in continuous ambulatory peritoneal dialysis

Objectives

Dry weight assessment (DWA) is an important part of dialysis and fluid management in patients receiving renal replacement therapy. With the development of bioimpedance analysis (BIA), the development of the direct segmental multi-frequency BIA (DSM–BIA) has provided a more convenient measure for DWA of dialysis patients, but its accuracy remains unclear. This study was designed to evaluate the application of DSM–BIA in DWA of continuous ambulatory peritoneal dialysis (CAPD) patients.

Design

This is a cross-sectional study. Using the conventional BIA as a reference, we examined the accuracy of the DSM–BIA technique for assessing dry weight in CAPD patients and analyzed the potential factors influencing their fluid volume status.

Setting and participants

A total of 31 patients with end-stage renal disease receiving CAPD and 310 healthy volunteers were recruited for this study.

Methods

The intraclass correlation coefficients (ICC) and Bland–Altman plots were used to assess the consistency between DSM–BIA and the conventional BIA for DWA. Univariate and multivariate linear regression analyses were used to explore the influencing factors associated with the edema index.

Results

DSM–BIA and the conventional BIA technology were consistent in DWA in CAPD patients (ICC female 0.972, ICC male 0.882, ICC total 0.960). Similarly, Bland–Altman plots showed good agreements between the two methods in DWA for both genders. Univariate and multivariate linear regression analysis showed both eGFR level (P = 0.04) and serum NT-pro BNP concentration (P = 0.007) were positively correlated with the ratio of extracellular water to total body water (ECW/TCW).

Conclusions

DSM–BIA in DWA has good accuracy in clinical applications and has potential application value for fluid volume management in CAPD patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11255-022-03281-7.

Left Ventricular Strain Analysis by Tissue Tracking- Cardiac Magnetic Resonance for early detection of Cardiac Dysfunction in children with End-Stage Renal Disease

BACKGROUND

Cardiovascular disease is a major cause of morbidity and mortality in end-stage renal disease (ESRD). Reduction in left ventricular ejection fraction (LVEF) represents late left ventricle (LV) dysfunction. Cardiac MRI myocardial strain analysis is an alternative method for assessment of LV function.

PURPOSE

To investigate whether LV strain analysis is more sensitive than LVEF for early detection of systolic dysfunction in children with ESRD.

STUDY TYPE

Case control.

POPULATION

Thirty-two children with ESRD (median 14 years, 17 females) and 10 healthy control (median 12.5 years, 7 females).

FIELD STRENGTH AND SEQUENCES

A 1.5 T /retrospective ECG-gated steady-state free precession (SSFP).

ASSESSMENT

LVEF, and indexed LV mass (LVMi) and LV end-diastolic volume (LVEDVi) were measured. Using tissue tracking analysis, LV endocardial and epicardial contours were traced in short and long axes at end diastole to calculate global longitudinal (GLS), circumferential (GCS) and radial (GRS) strains.

STATISTICAL ANALYSIS

Cardiac MRI and strain parameters were compared between patients and control, and between subgroup with preserved LVEF and control by Student t-test/Mann Whitney test. Diagnostic accuracy was assessed by Receiver operating characteristic analysis. Strain as predictor of poor outcome (mortality, pulmonary edema, and/or heart failure) within 1-year follow up was investigated by binary logistic regression.

RESULTS

Compared to control, cardiac MRI LVEF, LVEDVi, LVMi, GLS, GCS and GRS were significantly impaired in patients. Patients with preserved LVEF had significantly higher LVEDVi, LVMi and significantly impaired GCS and GRS than control. Strain parameters were significantly correlated with LVEF, LVEDVi, and LVMi. GCS and GRS demonstrated greater diagnostic accuracy than GLS (area under curve: 0.89). LVEF, LVMi, GCS, and GRS were correlated with poor outcome.

CONCLUSION

Cardiac MRI tissue tracking could identify subclinical LV dysfunction in children with ESRD and still preserved LVEF. Furthermore, LV strain parameters (GCS and GRS) were correlated with future cardiovascular events.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

Volume management as a key dimension of a high-quality PD prescription

BACKGROUND

Appropriate volume control is one of the key goals in a peritoneal dialysis (PD) prescription. As such it is an important component of the International Society of Peritoneal Dialysis (ISPD) guideline for "High-quality PD prescription" necessitating a review of the literature on volume management. The workgroup recognized the importance of including within its scope measures of volume status and blood pressure in prescribing high-quality PD therapy.

METHODS

A Medline and PubMed search for publications addressing volume status and its management in PD since the publication of the 2015 ISPD Adult Cardiovascular and Metabolic Guidelines, from October 2014 through to July 2019, was conducted.

RESULTS

There were no randomized controlled trials on blood pressure intervention and six randomized trials of bioimpedance-guided volume management. Generally, all studies were of small sample size, short duration, and used surrogate markers as primary outcomes. As a consequence, only "practice points" were drawn. High-quality goal-directed PD prescription should aim to achieve and maintain clinical euvolemia taking residual kidney function and its preservation into account, so that both fluid removal from peritoneal ultrafiltration and urine output are considered and residual kidney function is not compromised. Blood pressure should be included as a key objective parameter in assessing the quality of PD prescription but there is currently no evidence for a specific target in PD. Clinical examination remains the keystone of routine clinical care.

CONCLUSIONS

High-quality goal-directed PD prescription should include volume management as one of the key dimensions.

Ankle-brachial index, arterial stiffness, and biomarkers in the prediction of mortality and outcomes in patients with end-stage kidney disease

BACKGROUND

Although ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) are significant predictors of major adverse cardiovascular event (MACE), their prognostic value in association with biomarkers has not been fully evaluated in patients with end-stage kidney disease (ESKD).

HYPOTHESIS

We hypothesized that ABI/baPWV would provide better prognostic value independent of biomarkers in ESKD patients.

METHODS

This study included 104 ESKD patients treated with maintenance hemodialysis who underwent ABI and baPWV examinations and laboratory tests, including brain-natriuretic peptide, high-sensitive cardiac troponin T (hs-cTnT), and high-sensitive C-reactive protein (hs-CRP). MACE was defined as a composite event of all-cause death, acute coronary syndrome, and stroke.

RESULTS

During a mean follow-up of 3.6 ± 1.7 years, a total of 51 MACE were observed. The independent factors associated with MACE were age >75 years (adjusted hazard ratio [HR], 2.15; P < .05), abnormal ABI (adjusted HR, 2.01; P < .05), left ventricular ejection fraction (LVEF) <50% (adjusted HR, 3.33; P < .001), the upper tertile of hs-cTnT (adjusted HR, 2.77; P < .05), and hs-CRP (HR, 1.96; P < .05). However, baPWV did not remain as an independent predictor of MACE in the entire cohort and also in patients without abnormal ABI. The combination of predictors improves the predictive value of MACE, providing increased HR with 4.00 for abnormal ABI + hs-CRP, 4.42 for abnormal ABI + hs-cTnT, and 7.04 for abnormal ABI + LVEF <50% (all P < .001).

CONCLUSION

Abnormal ABI is a robust predictor of MACE independent of biomarkers and their combination provides better risk stratification compared with a single predictor in ESKD patients.

Cardiovascular magnetic resonance left ventricular strain in end-stage renal disease patients after kidney transplantation

BACKGROUND

Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function.

METHODS

We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12 months after KT.

RESULTS

Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p = 0.007) and global radial strain (GRS) (p = 0.003), but a decline in global longitudinal strain (GLS) over 12 months (p = 0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4 ± 6.4% at baseline, 60.6% ± 6.9% at 12 months; p = 0.001). For entire cohort, over 12 months, change in LVEF was significantly correlated with change in GCS (Spearman's r = - 0.42, p < 0.001), GRS (Spearman's r = 0.64, p < 0.001), and GLS (Spearman's r = - 0.34, p = 0.002). Improvements in GCS and GRS over 12 months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p < 0.05), but not with change in blood pressure (all p > 0.10).

CONCLUSIONS

Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12 months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.

The importance of residual renal function in peritoneal dialysis

BACKGROUND

Peritoneal dialysis (PD) patients with preserved residual diuresis have a lower risk of death and complications. Here we analyzed associations between residual diuresis and presence of fluid overload and biomarkers of cardiac strain and nutrition in PD patients.

METHODS

Among 44 PD patients placed into three subgroups, depending on volume of residual diuresis (group A ≤ 500; group B 600-1900; and group C ≥ 2000 mL/day), we examined: overhydration (OH) assessed by bioimpedance analysis (BIA; yielding OH index OHBIA) and by clinical criteria (edema and hypertension); nutritional status (by subjective global assessment, SGA); metabolic status (electrolytes, serum lipid profile, CRP, and albumin); biomarkers of fluid overload and cardiac strain (N-terminal probrain natriuretic peptide, NT-proBNP, and troponin T, TnT); and, echocardiography and chest X-ray.

RESULTS

With increasing residual diuresis in group A, B and C, fewer patients had signs of overhydration defined as OHBIA > 1.1 L (75.0, 42.9 and 33.3 %) or peripheral edema (25.0, 21.4 and 0 %) and NT-proBNP (15199 ± 16150 vs. 5930 ± 9256 vs. 2600 ± 3907 pg/mL; p < 0.05) and TnT (0.15 ± 0.17 vs. 0.07 ± 0.09 vs. 0.04 ± 0.03 ng/mL; p < 0.05) were significantly lower. Significant differences were found also in ejection fraction, SGA, and total cholesterol, albumin and hemoglobin levels whereas blood pressures and serum CRP did not differ significantly.

CONCLUSION

Signs of OH and cardiac strain are common in PD patients, even in those with diuresis of 1000-2000 mL/day and with no clinical signs or symptoms, suggesting that even moderate decrease in residual renal function in PD patients associate with OH and other complications.

Overhydration Negatively Affects Quality of Life in Peritoneal Dialysis Patients: Evidence from a Prospective Observational Study

Backgound: This study evaluated whether the hydration status affected health-related quality of life (HRQOL) during 12 months in peritoneal dialysis (PD) patients.

METHODS

The hydration status and the HRQOL were examined at baseline and after 12 months using a bioimpedance spectroscopy and Kidney Disease Quality of Life-Short Form, respectively in PD patients. Four hundred eighty-one patients were included and divided according to the baseline overhydration (OH) value; normohydration group (NH group, -2L≤ OH ≤+2L, n=266) and overhydration group (OH group, OH >+2L, n=215). Baseline HRQOL scores were compared between the two groups. The subjects were re-stratified into quartiles according to the OH difference (OH value at baseline - OH value at 12 months; <-1, -1 - -0.1, -0.1 - +1, and ≥+1L). The relations of OH difference with HRQOL scores at 12 months and the association of OH difference with the HRQOL score difference (HRQOL score at baseline - HRQOL score at 12 months) were assessed.

RESULTS

The OH group showed significantly lower baseline physical and mental health scores (PCS and MCS), and kidney disease component scores (KDCS) compared with the NH group (all, P<0.01). At 12 months, the adjusted PCS, MCS, and KDCS significantly increased as the OH difference quartiles increased (P<0.001, P=0.002, P<0.001, respectively). In multivariate analysis, the OH difference was independently associated with higher PCS (β = 2.04, P< .001), MCS (β=1.02, P=0.002), and KDCS (β=1.06, P<0.001) at 12 months. The OH difference was independently associated with the PCS difference (β = -1.81, P<0.001), MCS difference (β=-0.92, P=0.01), and KDCS difference (β=-0.90, P=0.001).

CONCLUSION

The hydration status was associated with HRQOL and increased hydration status negatively affected HRQOL after 12 months in PD patients.

Addition of N-terminal pro-B-type natriuretic peptide levels to electrocardiography criteria for detection of left ventricular hypertrophy: the ARIRANG study

The utility of electrocardiography (ECG) in screening for left ventricular hypertrophy (LVH) in general populations is limited mainly because its low sensitivity. B-type natriuretic peptide (BNP) is released due to the remodeling processes of LVH and could improve the diagnostic accuracy for the ECG criteria for LVH. We hypothesized that addition of BNP levels to ECG criteria could aid LVH detection compared with ECG alone in a general population. We enrolled consecutive 343 subjects from a community-based cohort. LVH was defined as LV mass index > 95 g/m(2) for females and > 115 g/m(2) for males according to echocardiography. The area under the receiver operator characteristic (ROC) curve to detect LVH was 0.55 (95% confidence interval [CI], 0.50-0.61) in Sokolow-Lyon criteria and 0.53 (0.47-0.59) in the Cornell voltage criteria. After addition of N-terminal-proBNP levels to the model, the corresponding areas under the ROC were 0.63 (0.58-0.69) and 0.64 (0.59-0.69), respectively. P values for the comparison in areas under the ROC for models with and without N-terminal-proBNP levels were < 0.001. These data suggest that addition of N-terminal-proBNP levels to ECG criteria could significantly improve the diagnostic accuracy of LVH in general populations.

N-terminal pro-B-type natriuretic peptide variability in stable dialysis patients

BACKGROUND AND OBJECTIVES

Monitoring N-terminal pro-B-type natriuretic peptide (NT-proBNP) may be useful for assessing cardiovascular risk in dialysis patients. However, its biologic variation is unknown, hindering the accurate interpretation of serial concentrations. The aims of this prospective cohort study were to estimate the within- and between-person coefficients of variation of NT-proBNP in stable dialysis patients, and derive the critical difference between measurements needed to exclude biologic and analytic variation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Fifty-five prevalent hemodialysis and peritoneal dialysis patients attending two hospitals were assessed weekly for 5 weeks and then monthly for 4 months between October 2010 and April 2012. Assessments were conducted at the same time in the dialysis cycle and entailed NT-proBNP testing, clinical review, electrocardiography, and bioimpedance spectroscopy. Patients were excluded if they became unstable.

RESULTS

This study analyzed 136 weekly and 113 monthly NT-proBNP measurements from 40 and 41 stable patients, respectively. Results showed that 22% had ischemic heart disease; 9% and 87% had left ventricular systolic and diastolic dysfunction, respectively. Respective between- and within-person coefficients of variation were 153% and 27% for weekly measurements, and 148% and 35% for monthly measurements. Within-person variation was unaffected by dialysis modality, hydration status, inflammation, or cardiac comorbidity. NT-proBNP concentrations measured at weekly intervals needed to increase by at least 46% or decrease by 84% to exclude change due to biologic and analytic variation alone with 90% certainty, whereas monthly measurements needed to increase by at least 119% or decrease by 54%.

CONCLUSIONS

The between-person variation of NT-proBNP was large and markedly greater than within-person variation, indicating that NT-proBNP testing might better be applied in the dialysis population using a relative-change strategy. Serial NT-proBNP concentrations need to double or halve to confidently exclude change due to analytic and biologic variation alone.

Predictors of left ventricular hypertrophy and their cutoffs in peritoneal dialysis patients

Cardiovascular complications are the main cause of morbidity and mortality in peritoneal dialysis (PD) patients. Left ventricular hypertrophy (LVH) is a major predictor of the development of cardiovascular events. This study aimed to identify risk factors that contribute to the development of LVH and to determine their cutoffs in patients on maintenance peritoneal dialysis.In this cross sectional study we evaluated the association of 23 variables including age, PD vintage, ultrafiltration, urine volume, residual renal function, mean daily SBP, mean daily DBP, fasting glucose, HbA1c, peritoneal glucose load index (PGLI), fluid overload (FO), plasma brain natriuretic peptide (BNP), plasma hsCRP and IL-6, serum albumin, white blood cell (WBC) count, hemoglobin, hematocrit, triglycerides, LDL-C (low density lipoprotein cholesterol), HDL-C (high density lipoprotein cholesterol), and PTH with LVH in 38 stable patients on maintenance PD ≥ 24 months.LVH was detected in 57.9% of patients. Logistic regression and receiver operating characteristics (ROC) analysis revealed that HbA1c, PGLI, FO, plasma BNP, hsCRP and IL-6 seem to be possible predictors of LVH. The cutoffs associated with the presence of LVH were: 7.5%, 3.2 g/kg/day, 1.7 L, 330 pg/mL, 7.5 mg/dL and 3.3 pg/mL for HbA1c, PGLI, FO, plasma BNP, hsCRP and IL-6, respectively (sensitivity 72.8 to 81.8% and specificity 75.0 to 93.8%).The results suggest that efforts should be made to reduce the peritoneal glucose load (PGL), to improve the hydration status, and to attenuate the inflammatory process in order to reduce the risk of the development of LVH among PD patients.

Modified Miller Banding Procedure for Managing High-flow Access and Dialysis-associated Steal Syndrome

Purpose

Both high-flow vascular access (VA) and dialysis-associated steal syndrome are serious complications requiring a flow reduction technique. We adopted the minimally invasive limited ligation endoluminal-assisted revision (MILLER) banding procedure with some modifications to control the high blood flow and steal syndrome during VA procedures and retrospectively assessed the outcome.

Methods

Seven patients with high-flow access (access flow >1400 ml/min) and five patients with steal syndrome (with pain, coldness, or cyanosis) were treated using the MILLER banding method. Flow volume of the brachial artery was monitored using Doppler ultrasonography during the banding procedure. In patients with steal syndrome, the finger probe of a pulse oximeter was attached to a finger on the ipsilateral side, and the peripheral oxygen saturation (SpO2) was monitored.

Results

In the high-flow group, the mean access blood flow (Qa) decreased from 2043 ± 463 ml/min (mean ± SD) to 1248 ± 388 ml/min (p<0.001). In the steal syndrome group, the SpO2 value improved in all steal syndrome patients after banding. Symptoms were almost relieved in two steal syndrome patients. The Qa in the steal group decreased from 997 ± 867 to 548 ± 376 ml/min (p = 0.12). The secondary patency rates of the high-flow and steal groups at 6 months were 83.3% and 50%, respectively.

Conclusions

The MILLER banding procedure with intraoperative access flow monitoring is effective to treat high-flow VA and steal syndrome.

Cardiac and oxidative stress biomarkers in Trypanosoma evansi infected camels: diagnostic and prognostic prominence

This study was conducted to investigate the level of cardiac and oxidative stress markers in camels infected with Trypanosoma evansi and to explore the diagnostic and prognostic value of cardiac troponin I (cTnI) and creatine kinase-myocardial band (CK-MB) in response to infection. Seventy four dromedary camels with clinical and laboratory evidence of trypanosomosis and 20 healthy controls were included in this study. Serum cTnI, CK-MB, CK, malondialdehyde (MDA) and super oxide dismutase (SOD) were measured. The values of cTnI, CK-MB, CK and MDA were significantly higher, whereas SOD level was lower in T. evansi infected camel. Successfully treated camels (n = 43) had lower levels of cTnI, CK-MB, CK and MDA, but higher level of SOD compared to camels with treatment failure. Both cTnI and CK-MB showed high degree of accuracy in predicting treatment outcome (success vs failure). The area under the curve for cTnI and CK-MB was 0.98 and 0.93, respectively. However, cTnI showed better sensitivity and specificity than CK-MB (Se = 96.8% vs 83.9% and Sp = 100% vs 88.5%, respectively). These results suggest that cTnI and CK-MB could be used as diagnostic and prognostic biomarkers in camels infected with T. evansi.

Long-term effects of spironolactone in peritoneal dialysis patients

ESRD treated with dialysis is associated with increased left ventricular hypertrophy, which, in turn, is related to high mortality. Mineralocorticoid receptor antagonists improve survival in patients with chronic heart failure; however, the effects in patients undergoing dialysis remain uncertain. We conducted a multicenter, open-label, prospective, randomized trial with 158 patients receiving angiotensin-converting enzyme inhibitor or angiotensin type 1 receptor antagonist and undergoing peritoneal dialysis with and without (control group) spironolactone for 2 years. As a primary endpoint, rate of change in left ventricular mass index assessed by echocardiography improved significantly at 6 (P=0.03), 18 (P=0.004), and 24 (P=0.01) months in patients taking spironolactone compared with the control group. Rate of change in left ventricular ejection fraction improved significantly at 24 weeks with spironolactone compared with nontreatment (P=0.02). The benefits of spironolactone were clear in patients with reduced residual renal function. As secondary endpoints, renal Kt/V and dialysate-to-plasma creatinine ratio did not differ significantly between groups during the observation period. No serious adverse effects, such as hyperkalemia, occurred. In this trial, spironolactone prevented cardiac hypertrophy and decreases in left ventricular ejection fraction in patients undergoing peritoneal dialysis, without significant adverse effects. Further studies, including those to determine relative effectiveness in women and men and to evaluate additional secondary endpoints, should confirm these data in a larger cohort.

The effect of tick infestation on the serum concentrations of the cardiac biomarker troponin I, acid-base balance and haematobiochemical profiles in camels (Camelus dromedarius)

The aim of the present study was to evaluate the serum concentration of cardiac troponin I (cTnI) in camels with tick infestation as a marker of potential myocardial injury and its prognostication. The effects of acid-base and electrolyte balance and haematobiochemical profiles were also investigated. Twenty-three camels (Camelus dromedarius) with tick infestation and suffering from anorexia, incoordination of movement, unsteady gait, recumbency, opisthotonus, anaemia and reduced production were examined. Ticks were visible, deeply embedded in the skin over the whole body, especially under the neck and around the udder or testis. Of the camels, 15 recovered after treatment and 8 did not. Blood samples were collected from the diseased camels on the day of admission to our clinic. Blood samples were also collected from 12 healthy camels and were used as controls. The mean serum concentration of cTnI in the camels with tick infestation was 1.7 ± 1.6 ng/ml compared to 0.03 ± 0.02 ng/ml in the controls. The mean serum concentration of cTnI in those camels that recovered was 0.36 ± 0.53 ng/ml compared to 3.0 ± 1.1 ng/ml in the camels that did not. Venous blood gas alterations included an increase in partial pressure of carbon dioxide and decreases in partial pressure of oxygen and oxygen saturation. Haematological parameters involved decreases of red blood cells, haemoglobin and haematocrit and increases in the mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration. Biochemical parameters included significant elevations in the serum activity of aspartate aminotransferase, creatine kinase and alkaline phosphates. Other biochemical alterations observed were decreases in total protein and albumin and increases in globulin and glucose concentrations. In conclusion, the data of this study suggest the possibility of using cTnI as a biomarker for cardiac injury in camels with tick infestation and for the prognosis of the outcome in the treated animals. Generally, values above 1.0 ng/ml were considered bad prognostic indicators.

Diagnostic Value of NT-ProBNP for Left Ventricular Hypertrophy in Hemodialysis Patients

We measured NT-proBNP levels in 30 stable patients on maintenance haemodialysis, before and after hemodialysis session with low-flux polysulfone dialyzers, all mesures were done by a third-generation assay (Elecsys Analyzer, Roche Diagnostics, Mannheim, Germany). We hypothesized that serum NT-proBNP cut-off value could serve as a biochemical marker to detect LVH in patients on haemodialysis treatment, regardless of chronic fluid overload. We assessed LV masse using trans-thoracic echocardiography, LVH was defined as an indexed left ventricular mass> 134 g/m2 in man and 110 g/m2 in woman. NT-proBNP levels increased significantly after hemodialysis sessions (5575,93 ± 5509,53 versus 4114,3856,37 ± pg/ml p<0,0001). A significant positive correlation was found between NT-proBNP level and left ventricular mass (r = 0.75, P<0.0001). NT-proBNP was significantly higher in patients with LVH: (5270,35 ± 3410,23 versus 2477,27 ± 1421,91 pg/ml P = 0,045). In the multivariate regression analysis NT-proBNP was the only independent predictor of LVH (r = 0.75, P<0.0001 Our results suggests that NT-proBNP could be a potential marker of LVH in chronic renal failure patients on hemodialysis.

Association of left ventricular longitudinal strain with mortality among stable hemodialysis patients with preserved left ventricular ejection fraction

BACKGROUND AND OBJECTIVES

Little is known about the optimal echocardiographic parameters for risk stratification in stable dialysis patients with preserved left ventricular ejection fraction (LVEF) (ejection fraction ≥ 50%). Left ventricular (LV) global peak systolic longitudinal strain (GLS) is the ratio of the maximal change in myocardial longitudinal length in systole to the original length and reliably and accurately assesses LV function. During systole, LV myocardium in the longitudinal direction shortens and GLS is represented by a negative value. The more negative value of GLS, the better the LV function is. This study hypothesized that subtle abnormalities of GLS are associated with an adverse prognosis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This prospective study collected clinical and echocardiographic data (including GLS) from 88 stable hemodialysis patients (mean age 67.0 ± 11.2 years; 35% men) with preserved LVEF. These patients were enrolled from December 2008 to January 2009 and were followed-up for 25.6 ± 9.9 months. The primary outcome was all-cause mortality. Multivariate Cox regression analysis was used to investigate risk factors for mortality.

RESULTS

The mortality group (n=24) had lower albumin levels, less negative GLS, and higher prevalence of coronary artery disease and diabetes mellitus than the survival group. Using a GLS cutoff value of -15%, the less negative GLS group (GLS ≥-15%) had a higher mortality rate. Cox regression analyses revealed that lower albumin level (hazard ratio, 0.16; 95% confidence interval, 0.05 to 0.53; P=0.003) and less negative GLS (hazard ratio, 3.57; 95% confidence interval, 1.41 to 9.04; P=0.01) were independent predictors of all-cause mortality. Furthermore, less negative GLS was associated with a higher cardiovascular death rate.

CONCLUSIONS

Less negative GLS is predictive of poor prognosis among stable hemodialysis patients with preserved LVEF.

Addition of highly sensitive troponin T and N-terminal pro-B-type natriuretic peptide to electrocardiography for detection of left ventricular hypertrophy: results from the Dallas Heart Study

Left ventricular hypertrophy (LVH) is an independent, modifiable risk factor for cardiovascular disease. However, current screening strategies are limited. In 2478 participants without clinical disease from the Dallas Heart Study, we evaluated a multimarker screening strategy that complements electrocardiographic (ECG) criteria for LVH with 2 biomarkers, amino-terminal pro-B-type natriuretic peptide and highly sensitive cardiac troponin T. An integer LVH risk score from 0 to 3 was determined as the sum of the following: (1) LVH by Sokolow-Lyon ECG; (2) amino-terminal pro-B-type natriuretic peptide in the highest sex-specific quartile; and (3) detectable cardiac troponin T. Cardiac magnetic resonance imaging-determined LVH served as the primary outcome. The probability of LVH increased from 2% with an LVH risk score of 0 to 50% with a score of 3 (P<0.001). Sokolow-Lyon ECG afforded low sensitivity (26% [95% confidence interval {CI}, 17-32%]) and high specificity (96% [95% CI, 95-97%]), whereas a risk score ≥2 offered higher sensitivity (44% [95% CI, 34-51%]) with good specificity (90% [95% CI, 89-93%]) and a score threshold of 1 offered reasonable sensitivity (76% [95% CI, 67-83%]) with lower specificity (55% [95% CI, 53-61%]) and high negative predictive value (98% [95% CI, 97-98%]). Area under the receiver operator characteristic curve improved from 0.760 (95% CI, 0.716-0.804) for ECG alone to 0.798 (95% CI, 0.754-0.842) for the LVH risk score (P=0.0012), consistent with modest improvement in overall discrimination. Better screening for LVH may be achieved by combining simple tests, which collectively provide additional information compared with ECG alone. Further studies are needed to evaluate the impact and cost-effectiveness of a multimarker screening strategy.

Changes in N-terminal pro-brain natriuretic peptide correlate with fluid volume changes assessed by bioimpedance in peritoneal dialysis patients

BACKGROUND/AIMS

Both brain natriuretic peptide (BNP) and volume overload are reported to be powerful predictors of survival for peritoneal dialysis patients. The usefulness of single BNP determinations in helping determine volume status in peritoneal dialysis patients remains controversial, so we reviewed serial BNP and multifrequency bioimpedance measurements to determine whether changes in BNP reflected changes in volume status.

METHODS

Prospective measurements of fluid volume by multifrequency bioimpedance and serum N-terminal pro-BNP (NTproBNP) were conducted in stable adult peritoneal dialysis outpatients attending for routine assessments of peritoneal dialysis adequacy and transport status.

RESULTS

A total of 189 serial measurements were made in 92 patients, and NTproBNP increased from a median of 162.5 pmol/l (interquartile range 82-385.4) to 195 pmol/l (interquartile range 101.9-348.6; p < 0.05). Changes in NTproBNP correlated with changes in extracellular water (ECW), total body water (TBW) and ECW/TBW (r = 0.38, 0.31 and 0.45, respectively; all p < 0.0001). Patients were divided into quartiles depending upon NTproBNP changes; those with the greatest fall in NTproBNP had significant falls in ECW (p < 0.001), TBW (p = 0.001) and ECW/TBW (p < 0.001) compared to the quartile with the greatest increase in NTproBNP, who also had an increase in systolic blood pressure from 133.5 ± 22.7 to 142.7 ± 28.8 mm Hg (p = 0.0078), whereas it fell in the quartile with the greatest fall in NTproBNP (143.8 ± 24.6 vs. 136.5 ± 18.7 mm Hg).

CONCLUSIONS

Serial measurements of NTproBNP correlated with changes in volume assessments made by multifrequency bioimpedance in peritoneal dialysis outpatients. As multifrequency bioimpedance measures total ECW, rather than effective plasma volume, serial NTproBNP determinations may prove an adjunct to the clinical assessment of volume status in peritoneal dialysis patients.

Biomarkers in hemodialysis patients

Patients with chronic kidney disease (CKD) are, compared to the general population, at higher risk of cardiovascular disease (CVD), including sudden death, coronary artery disease (CAD), congestive heart failure (HF), stroke, and peripheral artery disease. The presence of CVD is independently associated with kidney function decline. Renal insufficiency is a strong and independent predictor of mortality in patients with different CKD stages. The interplay of traditional and nontraditional risk factors is complex such that risk factor profiles are different in CKD patients. Seemingly, paradoxical associations between traditional risk factors and cardiovascular outcome complicate efforts to identify real cardiovascular etiology in these patients. Additional tools are often required to aid clinical assessment of cardiovascular risk. Recently, a number of cardiovascular biomarkers were identified as predictors of outcome in CVD. These may be used to guide early diagnosis and therapy for CVD or may predict outcome in CKD. This review focuses on the potential diagnostic and prognostic use of some important new biomarkers including brain natriuretic peptide (BNP), cardiac troponins (cTns), inflammatory markers, adhesion molecules, and asymmetric dimethylarginine (ADMA) in CKD as well as those patients with end-stage renal failure.

FGF-23 is associated with cardiac troponin T and mortality in hemodialysis patients

Fibroblast growth factor 23 (FGF-23) is elevated in patients with end-stage kidney disease and has been linked with mortality, vascular calcification, markers of bone turnover, and left ventricular hypertrophy. In this cohort study, we determined the correlates of FGF-23 (including cardiac troponin T [cTNT]) and determined its association with mortality over 3.5 years of follow-up in 103 prevalent hemodialysis patients. Mean age was 61.2 (15.5) and the mean dialysis vintage was 4.19 years (4.6). The median (interquartile range) FGF-23 was 1259 (491, 2885) RU/mL. Independent predictors (estimate standard error) of log-transformed FGF-23 concentrations included phosphorus (0.75 [0.237], P = 0.002) and cardiac troponin T (1.04 [0.41], P = 0.01). There were 57 deaths. In the fully adjusted model, the significant predictors of mortality included age and albumin. The independent association between FGF-23 and cTNT is a novel finding. Whether this relationship supports the possibility that a downstream effect of dysregulated phosphorous homeostasis may be enhanced cardiac remodeling requires further study.

Is N-terminal probrain-type natriuretic peptide a clinically useful biomarker of volume overload in peritoneal dialysis patients?

BACKGROUND

Brain natriuretic peptide (BNP) has been reported to be a powerful predictor of peritoneal dialysis patient survival. However, it is unclear as to whether this is related to cardiac dysfunction or chronic volume overload.

METHODS

To investigate the relationship between BNP, cardiac function and fluid volume overload, we reviewed multifrequency bioimpedance, transthoracic echocardiography and serum N-terminal probrain-type natriuretic peptide (NTproBNP) in 115 stable peritoneal dialysis outpatients attending for assessment of peritoneal dialysis and transport status.

RESULTS

In this cross-sectional study, the median NTproBNP was 251 (118-605) pmol/L. On simple univariate analysis, NTproBNP was associated with markers of residual renal function, volume overload, hypertension and hypertensive cardiac disease and inflammation [reduced serum albumin and raised C-reactive protein]. However, on multivariate logistical regression analysis, the strongest association for log NTproBNP was with the estimated right ventricular end-systolic pressure (β = 0.02, F = 11.5, P = 0.001), followed by log 24-h urine volume (β = -0.19, F = 10.7, P = 0.002), extracellular/total body water ratio (β = 13.5, F = 6.1, P = 0.017) and the number of different antihypertensive medications prescribed (β = 0.15, F = 8.7, P = 0.005).

CONCLUSION

In this cross-sectional study, although NTproBNP was associated with residual renal function, cardiac hypertrophy, volume overload and inflammation on simple univariate analysis, on further examination NTproBNP was predominantly affected by factors associated with volume overload, and these results require confirmation in a prospective study.

Current perspectives on diagnosis of heart failure in long-term dialysis patients

Cardiovascular disease is highly prevalent in patients with chronic kidney failure treated using dialysis. The risk of cardiovascular events is estimated to be at least 2- to 10-fold higher in dialysis patients than in age-, race-, and sex-matched persons with normal kidney function. A significant proportion of cardiovascular events in long-term dialysis patients is caused by heart failure, and the presence of heart failure is predictive of a poor prognosis. Despite the significant morbidity and mortality associated with heart failure, very few therapeutic options are proved to prevent and treat the progression of this complication in dialysis patients. There are several potential reasons for this, chiefly reflecting both challenges with diagnosis due to the coexistence of volume overload and a paucity of adequately powered prospective randomized controlled trials that examine the efficacy of different therapeutic options in dialysis patients with cardiac disease or heart failure. Thus, unlike in the general population, very few advances have been made in managing this severe complication in dialysis patients. In this article, an overview of the prevalence, severity, and risk factors for heart failure in maintenance dialysis patients is provided and the diagnosis of heart failure in these patients is revisited.

Is left ventricular hypertrophy a powerful predictor of progression to dialysis in chronic kidney disease?

BACKGROUND

The role of cardiovascular factors in predicting renal outcome has not been extensively elucidated. Herein, we report a prospective evaluation of the impact of left ventricular hypertrophy (LVH) on outcome in non-diabetic patients with chronic kidney disease (CKD).

METHODS

We studied 144 patients (99 men; age 62±14 years) with stage 3-4 CKD, with baseline assessment of left ventricular mass index (LVMi) by echocardiography, estimated glomerular filtration rate (eGFR) by MDRD equation, 24-h blood pressure profile and 24-h proteinuria. Combined end point was progression to ESRD requiring dialysis, or death within 5 years.

RESULTS

Forty-nine patients (34%) progressed to dialysis, 24 (17%) died, 57 (39%) were dialysis-free after 5 years and 14 were lost to follow-up. Multivariate Cox proportional hazards analysis showed that increased LVMi (HR 1.28, 95% CI 1.17-1.40 for each 10-g/m2 increase, P<0.0001) and reduced eGFR (5% risk increase for each 1-mL/min reduction, P=0.027) were the significant predictors of the combined end point in stage 3 CKD patients, whereas LVMi proved to be the only significant predictor of the combined end point in patients with stage 4 CKD (HR 1.19, 95% CI 1.09-1.31, P<0.0001). The same analysis showed that LVMi was the only significant predictor of progression to dialysis in stage 3 CKD patients (HR 1.42, 95% CI 1.23-1.64 for each 10-g/m2 increase, P<0.0001), while a 20% increase in the risk of progression to ESRD was observed for each 10-g/m2 increase in LVMi (P<0.0001), and a 10% increase for each 1-mL/min reduction in eGFR (P=0.046) in patients with stage 4 CKD. When evaluating the predictive role of LVMi on outcome using AUC-ROC curves, the overall performance of the model including LVMi (AUC 0.877, 95% CI 0.8-0.954) was superior to the model including eGFR (AUC 0.737, 95% CI 0.656-0.817) for the end point of progression to dialysis (P=0.026, Hanley test).

CONCLUSIONS

LVH proved to be the strongest predictor of the risk of progression to dialysis in non-diabetic CKD, especially among patients with less advanced renal dysfunction. Regardless of whether it is a simple marker or a pathogenetic factor, LVH encompasses all factors possibly affecting renal and general outcome in CKD patients.

Plasma myeloperoxidase, NT-proBNP, and troponin-I in patients on CAPD compared with those on regular hemodialysis

Myeloperoxidase (MPO) is a hemoprotein that is released during inflammation and may lead to irreversible protein and lipid modification, increasing levels of oxidized low density lipoprotein, and promoting athrogenesis. Recently, it has been considered as a risk factor for cardiovascular diseases. Similarly, the measurement of carotid intima-media thickness gives an indication about the degree of atherosclerosis and prediction of clinical cardiovascular events. Elevated white blood cells counts may indicate a state of acute inflammation and follow its progression. Dialysis patients are at a high risk of developing cardiovascular disease compared with healthy subjects. The role of N-terminal pro-brain natriuretic peptide and increased cardiac troponin in identification and prognostication of cardiovascular diseases in end-stage renal disease patients has been investigated. The current study aimed to evaluate plasma MPO and its possible relationship with carotid intima-media thickness, troponin I, N-terminal pro-brain natriuretic peptide (NT-proBNP), and insulin resistance as measured by homeostatic model assessment (HOMA index) in a cohort of Saudi patients who are undergoing hemodialysis (HD) vs. continuous ambulatory peritoneal dialysis for end-stage renal disease. Plasma MPO was significantly higher in patients on continuous ambulatory peritoneal dialysis (CAPD) than in those on HD and in normal subjects (P<0.001). Conversely, NT-proBNP plasma levels were significantly higher in patients on HD (both predialysis and postdialysis) than in those on CAPD (P<0.01) and than normal subjects. Similarly, plasma troponin-I levels were significantly higher in patients on HD compared with those of CAPD and than normal subjects (P<0.001). Plasma troponin-I and NT-proBNP levels were positively correlated in the 3 groups namely those on CAPD, Pre-HD, and post-HD (r: 0.464 and P=0.047; r: 0.330 and P=0.013; and r: 0.452 and P=0.024), respectively. There was no correlation between the MPO level and carotid intima-media thickness (P>0.05). However, plasma MPO level correlated positively with the white blood cell count in patients on CAPD and in those on HD (P<0.05). Our findings suggest an increased oxidative stress in CAPD patients compared with HD patients, while the reported difference in plasma NT-proBNP and troponin-I may be related to the rapid decline of residual renal function in HD and type of membrane used in the HD dialysis procedure itself.

Left ventricular growth after 1 year of haemodialysis does not correlate with arteriovenous access flow: a prospective cohort study

BACKGROUND

The incidence of congestive heart failure is 3-fold greater than that of acute coronary syndrome in haemodialysis (HD) patients. The purpose of this study was to determine if blood flow through an arteriovenous (AV) access contributes to an increase in left ventricular mass (LVM) that may increase the risk of congestive heart failure.

METHODS

We conducted a 1-year prospective cohort study at two Canadian centres of HD patients at high risk for congestive heart failure who had a first AV access created. Patients underwent echocardiography and measurement of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) levels before and 1-year post-AV access creation. Access flows were measured within the first month of access maturation and 1-year post-access creation. Data were analysed using descriptive statistics, Student's t-test, correlation coefficients and regression.

RESULTS

One-year post-AV access creation, LVM increased by 12.2 +/- 32% (P = 0.025) and plasma NT-proBNP levels increased by 170 +/- 465% (P = 0.02). The average AV access blood flow did not correlate with an increase in LVM or NT-proBNP levels.

CONCLUSIONS

In patients on chronic HD after 1 year, AV access flow does not correlate with increases in LVM by echocardiography or plasma levels of NT-proBNP.