Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
1.
Blood Purif ; 52(1): 86-90, 2023.
Article in English | MEDLINE | ID: mdl-36209726

ABSTRACT

INTRODUCTION: Significant variation exists in the prevalence of home haemodialysis (HHD) among UK renal centres. Our centre has a HHD prevalence of 2%, and we aimed to study how many patients who chose HHD as their preferred mode of renal replacement therapy (RRT) went on to receive this treatment and the barriers to starting this treatment. METHODS: A retrospective single-centre analysis of electronic medical records for all patients who chose HHD at the time of RRT education was performed, and data were collected on patient demographics, comorbidity, frailty, RRT events, and barriers to HHD. RESULTS: 116 patients chose HHD as their preferred mode of RRT between 2006 and 2018. Of these patients, 93 required RRT, but only 28 patients ever received HHD. No statistical difference was identified between those patients who only received unit haemodialysis (UHD) and those who went onto receive HHD with respect to age, gender, comorbidity, frailty, and socioeconomic deprivation. Patient choice, change in clinical condition, transplantation, home environment, vascular access problems, and training delays were identified as reasons patients did not start HHD. No documented reason could be found in 9 patients with a breakdown of communication between clinics and peripheral dialysis units attributed as a significant contributor in some of these patients. Of the 26 patients who started HHD after UHD, 19 did so within 1 year of starting UHD. CONCLUSION: Most patients who choose HHD do not receive HHD. Many patients never start HHD because of potentially reversible barriers including inadequate communication among clinicians about patient choices, patients changing their minds once in a dialysis unit, and inadequate timely training support.


Subject(s)
Frailty , Kidney Failure, Chronic , Humans , Hemodialysis, Home/methods , Renal Dialysis/methods , Retrospective Studies , Kidney Failure, Chronic/therapy
2.
Hemodial Int ; 24(4): 506-515, 2020 10.
Article in English | MEDLINE | ID: mdl-32844540

ABSTRACT

BACKGROUND: Hemodialysis (HD) induces myocardial stunning and is associated with adverse cardiovascular outcomes. Intradialytic hypotension is a modifiable determinant of myocardial stunning. Magnesium (Mg) is reported to be valuable in maintaining intradialytic blood pressure, which potentially would protect against demand myocardial ischemia. This study aimed to compare high vs. low dialysate Mg effects on intradialytic hemodynamics and HD-induced myocardial stunning. METHODS: Twenty stable prevalent HD patients entered a randomized cross-over trial of low (0.5 mmol/L) vs. high (1.0 mmol/L) dialysate Mg. Patients were studied after 2 weeks of standard HD with each Mg concentration. Serial echocardiography assessed myocardial stunning, measured by left ventricular regional wall motion abnormalities (RWMAs). Continuous intradialytic hemodynamics were measured noninvasively using thoracic bioimpedance. FINDINGS: Median predialysis serum Mg was higher with high dialysate Mg (1.45[1.29-1.55] vs. 1.03[0.98-1.1] mmol/L, P < 0.0001). There was no significant difference in maximum intradialytic reduction in systolic BP. There was no significant difference in stroke volume, total peripheral resistance, and cardiac output. Overall ventricular global longitudinal strain (GLS) (as a sensitive marker of contractile function) was higher before dialysis in high Mg group, but there was no difference in GLS at peak stress. However, we showed a significant correlation between Mg changes and GLS changes, r = -0.47, P = 0.02. There was no difference in mean number of peak stress RWMAs per patient (4.0 ± 2.2 vs. 4.3 ± 2.9, P = 0.5). Ultrafiltration volume, a critical determinant of stunning, was not different between high and low dialysate Mg studies (1.35[0-3.3] vs. 1.5[0-2.8], P = 0.49). DISCUSSION: Manipulation of magnesium by altering dialysate magnesium concentration does not influence intradialytic hemodynamic response or HD-induced myocardial stunning in the short term. However, decreasing Mg changes appears to decrease GLS changes.


Subject(s)
Dialysis Solutions/adverse effects , Hypotension/etiology , Magnesium/blood , Renal Dialysis/adverse effects , Adult , Aged , Cross-Over Studies , Female , Hemodynamics , Humans , Male , Middle Aged , Myocardial Stunning/physiopathology
3.
Hemodial Int ; 21(4): 519-523, 2017 10.
Article in English | MEDLINE | ID: mdl-27866393

ABSTRACT

INTRODUCTION: Repetitive dialysis-induced cardiac injury is associated with elevated troponin levels, inflammation, and longitudinal reduction in cardiac function. Pathogenic autoantibodies to cardiac troponins (cTnAAb) produce inflammatory cardiomyopathy in murine models. This study aimed to explore the possibility that analogous autoimmune processes might occur in hemodialysis (HD) patients, by initially investigating cTnAAb prevalence, and exploring potential links with HD-induced myocardial stunning. METHODS: In 130 prevalent HD patients from two centers (Derby, UK; Turku, Finland), cTnAAb (immunoassay) and cardiac troponins were quantified. Sixty-four patients underwent serial echocardiography to assess myocardial stunning. FINDINGS: cTnAAb were present in 7% of patients. Dual positivity to cTnAAb and elevated cTn occurred in 3% and 6% for cTnI and cTnT, respectively. Patients with cTnAAb had significantly longer dialysis vintage (82 vs. 30 months, P = 0.024), higher cTnT (0.1 vs. 0.05 pg/mL, P = 0.04), cTnI (0.02 vs. 0.01 pg/mL, P = 0.029), and free PAPP-A (6.4 vs. 3.3 mIU/L, P = 0.038). DISCUSSION: This is the first description of cTnAAb in HD patients, which raises the possibility that longitudinal exposure to repetitive HD-induced cardiac injury may lead to further autoimmune-based myocardial insult.


Subject(s)
Autoantibodies/adverse effects , Renal Dialysis/adverse effects , Troponin I/metabolism , Aged , Female , Humans , Male , Middle Aged , Renal Dialysis/methods
4.
Nephron ; 129(3): 171-8, 2015.
Article in English | MEDLINE | ID: mdl-25766334

ABSTRACT

BACKGROUND/AIMS: Pregnancy-associated plasma protein-A (PAPP-A) is a putative marker of atheroma instability and ischaemic myocardial stress prior to necrosis. Total PAPP-A (tPAPP-A) levels in acute coronary syndromes predict adverse outcomes. However, free PAPP-A (fPAPP-A) predominates in the circulation. Ischaemic haemodialysis (HD)-induced cardiac injury (myocardial stunning) is common and is associated with markers of myocardial necrosis, inflammation, cardiovascular events and mortality. Coronary plaque instability in pathophysiology of HD-induced myocardial stunning has not been studied. We aimed to investigate the relationship of fPAPP-A with stunning and mortality. METHODS: 130 prevalent patients from two HD centres (Finland and UK) were studied. Pre-HD free, complexed and total PAPP-A were measured by immunoassay. A subset of 62 patients underwent echocardiography to assess HD-induced myocardial stunning. The mean duration of follow-up was 407 ± 98 days. RESULTS: fPAPP-A was elevated (median: 3.45 mIU/l) and correlated with dialysis vintage (r = 0.391, p < 0.001), cardiac troponin T (cTnT; r = 0.29, p = 0.001) and cardiac troponin I (cTnI; r = 0.22, p = 0.01). PAPP-A was not related to stunning. Dialysis vintage and cTnT independently predicted Ln fPAPP-A (model R = 0.463). fPAPP-A, cTnT and age independently predicted death (Nagelkerke R(2) = 0.362). CONCLUSIONS: fPAPP-A, a novel predictor of HD-related mortality, demonstrates better prognostic power than tPAPP-A. Coronary plaque instability may contribute to sub-lethal myocardial injury, but may not be critical in pathogenesis of HD-induced ischaemic cardiac injury.


Subject(s)
Myocardial Ischemia/etiology , Pregnancy-Associated Plasma Protein-A/metabolism , Renal Dialysis/adverse effects , Renal Dialysis/mortality , Aged , Biomarkers , Cohort Studies , Female , Finland/epidemiology , Follow-Up Studies , Heart Function Tests , Humans , Inflammation/metabolism , Male , Middle Aged , Myocardial Ischemia/diagnostic imaging , Myocardial Stunning/etiology , Myocardial Stunning/physiopathology , Predictive Value of Tests , Pregnancy , Pregnancy-Associated Plasma Protein-A/analysis , Troponin C/blood , Ultrasonography
5.
Nephron Clin Pract ; 128(1-2): 141-6, 2014.
Article in English | MEDLINE | ID: mdl-25401768

ABSTRACT

BACKGROUND/AIMS: Endotoxaemia, a driver of systemic inflammation, appears to be driven by dialysis-induced circulatory stress in haemodialysis (HD) patients. More frequent HD regimens are associated with lower ultrafiltration requirements, improved haemodynamic stability and lower systemic inflammation. This study investigated the hypothesis that more frequently dialysed patients, with reduced exposure to dialysis-induced haemodynamic perturbation, would have lower circulating endotoxin (ET) levels. METHODS: A cross-sectional study of 86 established HD patients compared three groups: conventional HD 3× per week (HD3, n = 56), frequent HD 5-6× per week (SDHD, n = 20), and nocturnal HD (NHD, n = 10). Data collection included ultrafiltration volume and rate, serial blood pressures and blood sampling with quantification of ET, troponin T and high-sensitivity CRP (hsCRP). RESULTS: Pre-dialysis serum ET was highest in the conventional HD group (HD3 0.66 ± 0.29 EU/ml vs. NHD 0.08 ± 0.04 EU/ml). Across the study population, severity of endotoxaemia was associated with higher ultrafiltration rates, degree of intradialytic hypotension, troponin T and hsCRP levels. NHD patients had the lowest ultrafiltration requirements, the greatest haemodynamic stability and lower ET levels. CONCLUSION: More frequent HD regimens are associated with lower levels of circulating ET compared with conventional HD. Reduced ET translocation may be related to the greater haemodynamic stability of these treatments, with superior maintenance of splanchnic perfusion.


Subject(s)
Endotoxemia/blood , Endotoxemia/prevention & control , Endotoxins/blood , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Renal Dialysis/methods , Renal Dialysis/statistics & numerical data , Cross-Sectional Studies , Humans , Inflammation/blood , Male , Middle Aged , Troponin T/blood
6.
Can J Cardiol ; 30(11): 1422-8, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25228129

ABSTRACT

BACKGROUND: Strain analysis derived from the analysis of speckle tracked imaging echocardiography can be used to examine ventricular contractile functions. In this study, we examined the relationship of hemodialysis (HD)-induced circulatory stress with overall ventricular function assessed according to global longitudinal strain (GLS) and segmental distribution of strain. METHODS: This prospective observational study included 104 conventional HD patients at Royal Derby Hospital. Averaged values of segmental and GLS were determined from the echocardiography of these patients before and at peak dialysis. These values were compared with the reference values of healthy individuals, correlated with their demographic characteristics, and the effect on survival was assessed. RESULTS: The global strain value was -11.5% ± 4.42, and the segmental strain values were significantly greater in HD patients than in healthy individuals by 2.7%-9.8% (P < 0.001). The strain values were not significantly different before dialysis and at peak dialysis (P > 0.05), except within the basal lateral segment (P = 0.01). The adjusted hazard ratio for mortality was 4.3 (95% confidence interval, 1.2-14.9; P = 0.021) when > 80% of the segments exhibited more than the mean of segmental strain values. For the 46 patients who died, there were statistically significant negative correlations between survival time and GLS (r = -0.30; P = 0.04). CONCLUSIONS: Global and segmental strain measured using speckle tracked imaging provides information relating to the effects of HD-induced cardiac injury. The segmental strain abnormalities in the watershed area of the left ventricle suggest a higher degree of vulnerability to HD-induced demand ischemia.


Subject(s)
Echocardiography/methods , Myocardial Contraction/physiology , Renal Dialysis , Ventricular Dysfunction, Left/physiopathology , Ventricular Function, Left/physiology , Aged , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Time Factors , Ventricular Dysfunction, Left/diagnostic imaging
7.
Nephron Clin Pract ; 123(1-2): 118-22, 2013.
Article in English | MEDLINE | ID: mdl-23880872

ABSTRACT

BACKGROUND: Haemodialysis (HD) is able to induce recurrent myocardial ischemia and segmental left-ventricular dysfunction (myocardial stunning). The association of N-terminal Pro-B-type natriuretic peptide (NTpro-BNP) with HD-induced myocardial stunning is unclear. METHODS: In 70 prevalent HD patients, HD-induced myocardial stunning was assessed echocardiographically at baseline and after 12 months. The extent to which pre-dialysis NTpro-BNP was associated with the occurrence of HD-induced myocardial stunning was assessed as the primary endpoint. RESULTS: The median Ntpro-BNP concentration in this cohort was 2,154 pg/ml (IQR 1,224-3,014). Patients experiencing HD-induced myocardial stunning at either time point displayed elevated NTpro-BNP values (2,418 pg/ml, IQR, 1,583-3,474 vs. 1,751 pg/ml, IQR (536-2,029), p = 0.02). NTpro-BNP levels did not differ between patients showing HD-induced stunning at baseline and those developing stunning during the observational period (p = 0.8). NTpro-BNP levels drawn at the beginning of the dialysis session achieved a poor diagnostic accuracy for the detection of myocardial stunning (area under the ROC curve 0.61, 95% CI 0.45-0.77), but provided an accurate rule out for myocardial stunning during the subsequent year (AUC 0.85, 95% CI 0.70-0.99). The calculated cut-off of 1,570 pg/ml achieved a sensitivity of 66% and a specificity of 78% for the exclusion of myocardial stunning at any time point. In logistic regression analysis, only low NTpro-BNP levels (OR 0.92 for every additional 100 pg/ml, 95% CI 0.85-0.99, p = 0.03) were significantly associated with absence of myocardial stunning at any time point. CONCLUSION: Predialytic NTpro-BNP levels fail to adequately diagnose current dialysis-induced myocardial stunning, but help to identify patients with a propensity to develop dialysis-induced myocardial stunning at any time during the next 12 months.


Subject(s)
Kidney Failure, Chronic/blood , Kidney Failure, Chronic/rehabilitation , Myocardial Stunning/blood , Myocardial Stunning/epidemiology , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Renal Dialysis/statistics & numerical data , Causality , Comorbidity , Female , Humans , Kidney Failure, Chronic/epidemiology , Male , Middle Aged , Myocardial Stunning/diagnosis , Prevalence , Reproducibility of Results , Risk Factors , Sensitivity and Specificity , Statistics as Topic , Treatment Outcome , United Kingdom/epidemiology
8.
Clin J Am Soc Nephrol ; 7(8): 1285-92, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22822013

ABSTRACT

BACKGROUND AND OBJECTIVES: Circulating troponin T levels are frequently elevated in patients undergoing long-term dialysis. The pathophysiology underlying these elevations is controversial. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In 70 prevalent hemodialysis (HD) patients, HD-induced myocardial stunning was assessed echocardiographically at baseline and after 12 months. Nineteen patients were not available for the follow-up analysis. The extent to which predialysis troponin T was associated with the occurrence of HD-induced myocardial stunning was assessed as the primary endpoint. RESULTS: The median troponin T level in this hemodialysis cohort was 0.06 ng/ml (interquartile range, 0.02-0.10). At baseline, 64% of patients experienced myocardial stunning. These patients showed significantly higher troponin T levels than patients without stunning (0.08 ng/ml [0.05-0.12] versus 0.02 ng/ml [0.01-0.05]). Troponin T levels were significantly correlated to measures of myocardial stunning severity (number of affected segments: r=0.42; change in ejection fraction from beginning of dialysis to end of dialysis: r=-0.45). In receiver-operating characteristic analyses, predialytic troponin T achieved an area under the curve of 0.82 for the detection of myocardial stunning. In multivariable analysis, only ultrafiltration volume (odds ratio, 4.38 for every additional liter) and troponin T (odds ratio, 9.33 for every additional 0.1 ng/ml) were independently associated with myocardial stunning. After 12 months, nine patients had newly developed myocardial stunning and showed a significant increase in troponin T over baseline (0.03 ng/ml at baseline versus 0.05 ng/ml at year 1). CONCLUSIONS: Troponin T levels in HD patients are associated with the presence and severity of HD-induced myocardial stunning.


Subject(s)
Myocardial Stunning/diagnosis , Renal Dialysis/adverse effects , Troponin T/blood , Aged , Biomarkers/blood , England , Female , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Myocardial Stunning/blood , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Odds Ratio , Predictive Value of Tests , ROC Curve , Risk Assessment , Risk Factors , Severity of Illness Index , Time Factors , Ultrasonography , Up-Regulation
9.
Nephrol Dial Transplant ; 27(5): 1867-72, 2012 May.
Article in English | MEDLINE | ID: mdl-21976741

ABSTRACT

BACKGROUND: The pathophysiology of aggravated atherosclerosis in chronic kidney disease (CKD) is still incompletely understood. However, there is an increasing focus on non-traditional risk factors, including endothelial dysfunction. Angiopoietin-2 (Ang-2) impairs endothelial function by inhibiting the binding of Angiopoietin-1 (Ang-1) to their shared receptor Tie2 and is increased in diabetes, hypertension, coronary heart disease and CKD. Furthermore, Ang-2 levels are associated with the prevalent vascular burden of CKD patients. Thus, we aimed to investigate its impact on outcome in CKD, the population most likely to die of cardiovascular events. METHODS: We prospectively studied 128 CKD patients [43 CKD Stage 4, 85 CKD Stage 5 (57 haemodialysis, 28 peritoneal dialysis)] over a follow-up period of 4 years. Biochemical and clinical parameters, including objective scoring of vascular calcification (VC) by computed tomography (CT) and arterial stiffness by applanation tonometry (including radial-dorsalis pedis pulse wave velocity (PWVrd)) were recorded. Baseline Ang-1 [enzyme-linked immunosorbent assay (ELISA)], Ang-2 [immunoluminometric assay (ILMA)] and soluble Tie2 (sTie2) (ELISA) levels were measured in this group as well as in 20 healthy controls. RESULTS: Ang-2 values were significantly higher in CKD patients than in controls (2.01 ± 0.94 versus 1.00 ± 0.47 ng/mL, P < 0.0001). Furthermore, Ang-2 was significantly higher in dialysis than in Stage 4 CKD patients and correlated with markers of vascular disease [cholesterol, hsCRP, osteoprotegerin (OPG)]. However, elevated Ang-2 was not associated with the degree of VC or with arterial stiffness. Cox-regression analysis detected Ang-2 as an independent predictor of mortality in both unadjusted [hazard ratio (HR) 1.15; P = 0.002] and models adjusted for age and VC (HR 1.14; P = 0.003). CONCLUSIONS: Ang-2 levels are associated with systemic markers/mediators of micro-inflammation in CKD patients. Furthermore, elevated Ang-2 levels are strong predictors of long-term mortality, independent of conduit arterial stiffness or VC.


Subject(s)
Angiopoietin-2/blood , Kidney Diseases/mortality , Kidney Diseases/therapy , Peritoneal Dialysis , Renal Dialysis , Adult , Aged , Aged, 80 and over , Angiopoietin-1/blood , Atherosclerosis/epidemiology , Atherosclerosis/physiopathology , Biomarkers/blood , Case-Control Studies , Chronic Disease , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Kidney Diseases/blood , Longitudinal Studies , Male , Middle Aged , Predictive Value of Tests , Prevalence , Prospective Studies , Receptor, TIE-2/blood , Survival Rate , Vascular Stiffness/physiology
10.
Clin J Am Soc Nephrol ; 6(6): 1326-32, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21597028

ABSTRACT

BACKGROUND AND OBJECTIVES: Recurrent hemodialysis (HD)-induced ischemic cardiac injury (myocardial stunning) is common and associated with high ultrafiltration (UF) requirements, intradialytic hypotension, long-term loss of systolic function, increased likelihood of cardiovascular events, and death. More frequent HD regimens are associated with lower UF requirements and improved hemodynamic tolerability, improved cardiovascular outcomes, and reduced mortality compared with conventional thrice-weekly HD. This study investigated the hypothesis that modification of UF volume and rate with more frequent HD therapies would abrogate dialysis-induced myocardial stunning. DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS: A cross-sectional study of 46 patients established on hemodialysis >3 months compared four groups receiving the current range of quotidian therapies: conventional thrice-weekly HD (CHD3); more-frequent HD five to six times/week in a center (CSD) and at home (HSD); and home nocturnal HD (HN). Serial echocardiography quantitatively assessed regional systolic function to identify intradialytic left ventricular regional wall motion abnormalities (RWMAs). Cardiac troponin T (cTnT), N-terminal prohormone brain natriuretic peptide (NT-proBNP), and inflammatory markers were quantified. RESULTS: More frequent HD regimens were associated with lower UF volumes and rates compared with CHD3. Intradialytic fall in systolic BP was reduced in CSD and HSD groups and abolished in HN group. Mean RWMAs per patient reduced with increasing dialysis intensity (CHD3 > CSD > HSD > HN). Home-based groups demonstrated lower high-sensitivity C-reative protein levels, with trends to lower cTnT and NT-proBNP levels in the more frequent groups. CONCLUSIONS: Frequent HD regimes are associated with less dialysis-induced myocardial stunning compared with conventional HD. This may contribute to improved outcomes associated with frequent HD therapies.


Subject(s)
Myocardial Stunning/prevention & control , Renal Dialysis/methods , Adult , Aged , Biomarkers/blood , Blood Pressure , C-Reactive Protein/metabolism , California , Cross-Sectional Studies , Female , Humans , Inflammation Mediators/blood , Male , Middle Aged , Myocardial Stunning/blood , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Myocardial Stunning/physiopathology , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Renal Dialysis/adverse effects , Time Factors , Treatment Outcome , Troponin T/blood , Ultrasonography
11.
Blood Purif ; 32(1): 63-8, 2011.
Article in English | MEDLINE | ID: mdl-21346338

ABSTRACT

BACKGROUND/AIMS: Haemodialysis-induced myocardial stunning is associated with intradialytic hypotension, increased likelihood of cardiovascular events and death. Dialysis at 35°C reduces stunning, but adverse thermal symptoms limit technique adoption. This study investigated whether individualised body temperature dialysis improves haemodynamic stability and abrogates stunning. METHODS: Randomised crossover study of 11 patients compared LV regional wall motion abnormalities (RWMAs) at 37°C (HD(37)) and body temperature ('individualised', HD(ind)). Regional systolic function was quantitatively assessed by echocardiography. Haemodynamics were assessed using continuous pulse wave analysis. Thermal symptoms were scored by questionnaire. RESULTS: Mean predialysis body temperature was 36.0 ± 0.1°C. Mean number of peak stress RWMAs per patient was lower with HD(ind) (3.9 ± 1.4 vs. 5.3 ± 1.5, p = 0.03). Intradialytic systolic BP was higher during HD(ind) versus HD(37) (p < 0.001). Individualised body temperature dialysis demonstrated symptomatic tolerability comparable to HD(37). CONCLUSIONS: Individualised-temperature haemodialysis abrogates stunning, providing effective haemodynamic stabilisation at no additional therapy cost.


Subject(s)
Hemodynamics , Kidney Failure, Chronic/therapy , Myocardial Stunning/prevention & control , Precision Medicine/methods , Renal Dialysis/adverse effects , Systole/physiology , Aged , Aged, 80 and over , Blood Pressure , Body Temperature , Cross-Over Studies , Dialysis Solutions , Echocardiography , Female , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Humans , Kidney Failure, Chronic/physiopathology , Male , Middle Aged , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Myocardial Stunning/physiopathology , Precision Medicine/economics , Prospective Studies , Temperature
12.
Clin J Am Soc Nephrol ; 6(1): 133-41, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20876680

ABSTRACT

BACKGROUND AND OBJECTIVES: Translocated endotoxin derived from intestinal bacteria has a wide range of adverse effects on cardiovascular (CV) structure and function, driving systemic inflammation, atherosclerosis and oxidative stress. This study's aim was to investigate endotoxemia across the spectrum of chronic kidney disease (CKD). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Circulating endotoxin was measured in 249 patients comprising CKD stage 3 to 5 and a comparator cohort of hypertensive patients without significant renal impairment. Patients underwent extended CV assessment, including pulse wave velocity and vascular calcification. Hemodialysis (HD) patients also received detailed echocardiographic-based intradialytic assessments. Patients were followed up for 1 year to assess survival. RESULTS: Circulating endotoxemia was most notable in those with the highest CV disease burden (increasing with CKD stage), and a sharp increase was observed after initiation of HD. In HD patients, predialysis endotoxin correlated with dialysis-induced hemodynamic stress (ultrafiltration volume, relative hypotension), myocardial stunning, serum cardiac troponin T, and high-sensitivity C-reactive protein. Endotoxemia was associated with risk of mortality. CONCLUSIONS: CKD patients are characteristically exposed to significant endotoxemia. In particular, HD-induced systemic circulatory stress and recurrent regional ischemia may lead to increased endotoxin translocation from the gut. Resultant endotoxemia is associated with systemic inflammation, markers of malnutrition, cardiac injury, and reduced survival. This represents a crucial missing link in understanding the pathophysiology of the grossly elevated CV disease risk in CKD patients, highlighting the potential toxicity of conventional HD and providing a novel set of potential therapeutic strategies to reduce CV mortality in CKD patients.


Subject(s)
Cardiovascular Diseases/etiology , Endotoxemia/complications , Inflammation/etiology , Kidney Diseases/complications , Adult , Aged , Chronic Disease , Cross-Sectional Studies , Female , Humans , Linear Models , Male , Middle Aged , Renal Dialysis
13.
Clin J Am Soc Nephrol ; 5(1): 51-5, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19965551

ABSTRACT

BACKGROUND AND OBJECTIVES: Tissue-advanced glycation end products (AGE) are a measure of cumulative metabolic stress. Assessment of tissue AGE by skin autofluoresence (AF) correlates well with cardiovascular outcomes in hemodialysis (HD) patients. This study aimed to measure and compare tissue AGE levels in HD and peritoneal dialysis (PD) patients and to evaluate the impact of systemic PD glucose exposure. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Tissue AGE were measured in 115 established dialysis patients (62 HD and 53 PD) using a cutaneous AF device (AGE Reader; DiagnOptics). Values were compared with an age-matched non-chronic kidney disease database. Review of all previous PD solution delivery/prescription data determined PD glucose exposure. RESULTS: PD patients were similar in age to HD patients but had a shorter dialysis vintage. There were no differences in ischemic heart disease or smoking history, statin or angiotensin-converting enzyme inhibitor (ACEi) use, lipids, biochemistry, or prevalence of diabetes. More than 90% of both groups had met current dialysis adequacy targets. Skin AF values in PD and HD patients were similar and strongly correlated with historical PD glucose exposure. Skin AF correlated with age in both groups but with dialysis vintage only in PD patients CONCLUSIONS: Cumulative metabolic stress and transient hyperglycemia results in grossly elevated levels of tissue AGE in dialysis patients. In PD patients, this high level of AGE deposition is associated with historical glucose exposure. This observation provides a previously unappreciated potential link between PD exposure to glucose and systemic cardiovascular disease.


Subject(s)
Glycation End Products, Advanced/analysis , Renal Dialysis , Aged , Cross-Sectional Studies , Female , Fluorescence , Humans , Male , Middle Aged , Peritoneal Dialysis , Skin
14.
Clin J Am Soc Nephrol ; 4(12): 1925-31, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19808220

ABSTRACT

BACKGROUND AND OBJECTIVES: Hemodialysis (HD)-induced regional wall motion abnormalities (RWMAs) are common in HD patients and driven by ischemia. In nondialysis patients, repeated ischemia leads to chronic reduction in left ventricular (LV) function. HD-induced myocardial ischemia may initiate the same process. We examined the effect of HD-induced repetitive myocardial stunning on global and regional LV function. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS: We analyzed data from 30 patients, previously identified as developing HD-induced myocardial ischemia. Serial echocardiographic assessments of global and regional LV performance were performed at baseline and repeated after 12 mo. RESULTS: Several patients developed segments with a fixed reduction in systolic function of >60% after 1 yr. In this patient group, there was a significant reduction in resting LV ejection fraction (EF) from 61.5 +/- 10.1% to 52.9 +/- 8.6% (P < 0.007). Peak LV EF in response to dialysis also decreased from 59.5 +/- 10% versus 49.9 +/- 6.5% (P < 0.003), with a consequent increase in HD-induced hypotension (P < 0.0001). CONCLUSIONS: HD-induced myocardial stunning may progress over 12 mo to the development of regional fixed systolic dysfunction, consistent with underlying myocardial hibernation and fibrosis. This may be an important and potentially modifiable process in the development of heart failure in HD patients.


Subject(s)
Heart Failure, Systolic/etiology , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/physiopathology , Myocardial Ischemia/physiopathology , Myocardial Stunning/etiology , Renal Dialysis/adverse effects , Aged , Blood Pressure , Comorbidity , Disease Progression , Female , Follow-Up Studies , Heart Failure, Systolic/epidemiology , Heart Failure, Systolic/physiopathology , Humans , Hypertension, Renal/complications , Hypertension, Renal/epidemiology , Hypertension, Renal/physiopathology , Male , Middle Aged , Myocardial Ischemia/epidemiology , Myocardial Ischemia/etiology , Myocardial Stunning/epidemiology , Myocardial Stunning/physiopathology , Ventricular Dysfunction, Left/epidemiology , Ventricular Dysfunction, Left/etiology , Ventricular Dysfunction, Left/physiopathology
15.
Clin J Am Soc Nephrol ; 4(5): 914-20, 2009 May.
Article in English | MEDLINE | ID: mdl-19357245

ABSTRACT

BACKGROUND AND OBJECTIVES: Hemodialysis (HD)-induced myocardial stunning driven by ischemia is a recognized complication of HD, which can be ameliorated by HD techniques that improve hemodynamics. In nondialysis patients, repeated ischemia leads to chronic reduction in left ventricular (LV) function. HD may initiate and drive the same process. In this study, we examined the prevalence and associations of HD-induced repetitive myocardial injury and long-term effects on LV function and patient outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Seventy prevalent HD patients were assessed for evidence of subclinical myocardial injury at baseline using serial echocardiography and followed up after 12 mo. Intradialytic blood pressure, hematologic and biochemical samples, and patient demographics were also collected at both time points. RESULTS: Sixty-four percent of patients had significant myocardial stunning during HD. Age, ultrafiltration volumes, intradialytic hypotension, and cardiac troponin-T (cTnT) levels were independent determinants associated with its presence. Myocardial stunning was associated with increased relative mortality at 12 mo (P = 0.019). Cox regression analysis showed increased hazard of death in patients with myocardial stunning and elevated cTnT than in patients with elevated cTnT alone (P < 0.02). Patients with myocardial stunning who survived 12 mo had significantly lower LV ejection fractions at rest and on HD (P < 0.001). CONCLUSIONS: HD-induced myocardial stunning is common, and may contribute to the development of heart failure and increased mortality in HD patients. Enhanced understanding of dialysis-induced cardiac injury may provide novel therapeutic targets to reduce currently excessive rates of cardiovascular morbidity and mortality.


Subject(s)
Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/therapy , Myocardial Stunning/etiology , Myocardial Stunning/mortality , Renal Dialysis/adverse effects , Renal Dialysis/mortality , Aged , Blood Pressure , Female , Follow-Up Studies , Heart Failure/etiology , Heart Failure/mortality , Humans , Male , Middle Aged , Morbidity , Multivariate Analysis , Prevalence , Risk Factors , Survival Analysis
16.
NDT Plus ; 1(6): 383-391, 2008 Dec.
Article in English | MEDLINE | ID: mdl-28657024

ABSTRACT

Cardiovascular mortality is grossly elevated in patients with chronic kidney disease (CKD), and is associated with a wide variety of structural and functional abnormalities. These issues have driven additional attempts to further characterise these abnormalities to elucidate the pathophysiology involved, assess individual risk and/or target and monitor therapies specifically directed at the cardiovascular (CV) system. This review aims to assess the techniques that are currently available for the study of the CV system. This includes conventional assessments of the whole CV system from heart to peripheral microcirculation (although not deal with VC assessment), as well as the key functional consequences relating to stress induced cardiovascular reserve, perfusion and vasoregulation. In addition this review will introduce a variety of techniques aiming to expand the envelope of conventional measurements.

SELECTION OF CITATIONS
SEARCH DETAIL
...