Dissecting the mechanisms of left ventricular diastolic dysfunction and inflammation in peritoneal dialysis patients

Epicardial Adipose Tissue Thickness and Preserved Ejection Fraction Heart Failure

PURPOSE OF THE REVIEW

Preserved ejection fraction heart failure and obesity frequently coexist. Whether obesity plays a consistent role in the pathogenesis of preserved ejection fraction heart failure is unclear. Accumulation of visceral adiposity underlies the pathogenic aftermaths of obesity. However, visceral adiposity imaging is assessed by computed tomography or magnetic resonance and thus not routinely available. In contrast, epicardial adiposity thickness is assessed by echocardiography and thus routinely available. We review the rationale for assessing epicardial adiposity thickness in patients with preserved ejection fraction heart failure and elevated body mass index.

RECENT FINDINGS

Body mass index correlates poorly with visceral, and epicardial adiposity. Visceral and epicardial adiposity enlarges as preserved ejection fraction heart failure progresses. Epicardial adiposity may hasten the progression of coronary artery disease and impairs left ventricular sub-endocardial perfusion and diastolic function. Epicardial adiposity thickness may help monitor the therapeutic response in patients with preserved ejection failure heart failure and elevated body mass index.

The Association of Pre-Kidney Transplant Dialysis Modality with de novo Posttransplant Heart Failure

BACKGROUND

Heart failure (HF) after kidney transplantation is a significant but understudied problem. Pretransplant dialysis modality could influence incident HF risk through differing cardiac stressors. However, whether pretransplant dialysis modality is associated with the development of posttransplant HF is unknown.

METHODS

We used the US Renal Data System to assemble a cohort of 27,701 patients who underwent their first kidney transplant in the USA between the years 2005 and 2012 and who had Medicare fee-for-service coverage for >6 months preceding their transplant date. Patients with any HF diagnosis prior to transplant were excluded. Detailed baseline patient characteristics and comorbidities were abstracted. The outcome of interest was de novo posttransplant HF. Pretransplant dialysis modality was defined as the dialysis modality used at the time of transplant. We conducted time-to-event analyses using Cox regression. Death was treated as a competing risk in the study's primary analysis. Graft failure was included as a time-varying covariate.

RESULTS

Among eligible patients, 81% were treated with hemodialysis prior to transplant, and hemodialysis patients were more likely to be male, had a shorter dialysis vintage, and had more diabetes and vascular disease diagnoses. When adjusted for all available demographic and clinical data, pretransplant treatment with hemodialysis (vs. peritoneal dialysis) was associated with a 19% increased risk in de novo posttransplant HF, with sub-distribution HR 1.19 (95% CI: 1.09-1.29).

CONCLUSIONS

Our results suggest that choice of pretransplant dialysis modality may impact the development of posttransplant HF.

Systemic Action of Inflammatory Mediators in Patients with Essential Hypertension and Diastolic Chronic Heart Failure: A Clinical Pathophysiological Study

The aim of this research was to correlate indicators of proinflammatory status and the structural/functional characteristics of the cardiovascular system comparatively in male and female patients with essential hypertension (EH) complicated by diastolic chronic heart failure (CHF) with preserved left ventricular ejection fraction (LVEF). The study included 104 middle-aged patients (55 males (M) and 49 females (F)) with first- or second-degree EH complicated by CHF with preserved LVEF. They all belonged to the low functional class of CHF, with LVEF ≥50%, first- or second-degree of LV diastolic dysfunction (LVDD), LV hypertrophy (LVH), and dilatation of the left atrium (LA) with a sinus rhythm and N-terminal brain natriuretic peptide >125 pg/mL. Serum levels of C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6) were measured. To identify the relationship between the proinflammatory pattern and cardiovascular parameters, Spearman's rank correlation coefficients were determined. M had markedly higher levels of CRP, TNF-α, and IL-6 compared to F. However, all the mean values corresponded to the reference range. Significant direct associations of CRP level with the LV mass index (LVMI), relative wall thickness (RWT), LA volume index (LAVI), E/e' ratio, and systolic and diastolic blood pressure (SBP, DBP) existed in both M and F, as well as negative correlations of CRP with LVDD parameter e' and distance covered in a 6 min walk test. M and F had a positive association between IL-6 and LVMI, LAVI, E/e' ratio, SBP, RWT, and DBP, as well as strong negative associations between IL-6 and e' and distance passed in 6 min in each group. Significant direct correlations existed between serum TNF-α level and LVMI, RWT, LAVI, E/e', SBP, and DBP both in M and F. Furthermore, there were negative relationships of TNF-α level with e' and the distance covered for the 6 min walk. This study demonstrated a close relationship between the blood levels of proinflammatory autacoids and indicators of EH, exercise tolerance, LVH, LVDD, and LA enlargement, regardless of the patient's sex. Compared to female patients, male patients had stronger correlations of CRP, TNF-α, and IL-6 levels with indicators of LVDD degree.

Associations of left ventricular systolic dysfunction with the factors among Thai patients on peritoneal dialysis: a cross-sectional study

Background

Factors associated with left ventricular systolic dysfunction (LVSD) of peritoneal dialysis (PD) patients are limited. We aim to explore and quantify the associated factors of LVSD among PD patients.

Methods

Participants from a PD clinic treated between 2012 and 2014 at the HRH Princess Maha Chakri Sirindhorn Medical Center, Srinakharinwirot University, Nakhon Nayok, Thailand were recruited and divided into 2 groups according to their left ventricular ejection fraction (LVEF) (< 50% vs. ≥ 50%) with LVEF < 50% considered as LVSD. Correlations among the clinical, laboratory and echocardiographic variables were analyzed. The factors associated with LVSD were explored with univariate and multivariate logistic regression analyses. Beta coefficient along with odds ratio and 95% confidence interval (CI) were calculated and the P value < 0.05 was considered significant.

Results

Among 103 subjects stratified as LVSD (n = 18, 17.5%). The mean (SD) age was 59.3 (12.7) years, and nearly halves were males. Preexisting CAD, diabetes (DM) and current smoking were 20 (19.4%), 63 (61.2%) and 23 (22.3%) patients, respectively. The median time of dialysis vintage was 12 (3, 24) months. Factors associated with LVSD and corresponding ORs with 95% CI by multivariate analysis were prior coronary artery disease (CAD) [5.08 (1.16, 22.19)], DM [6.36 (1.29, 31.49)], smoking [10.62 (2.17, 51.99)], neutrophil to lymphocyte ratio (NLR) > 3.6 [6.77 (1.41, 32.52)], and high serum phosphate [9.39 (2.16, 40.92)] were significantly associated with LVSD.

Conclusions

Prior history of CAD, DM, smoking, high NLR and serum phosphate levels were found to be associated with LVSD for our PD patients. The evidence from prospective study is needed to confirm the predictive value of these variables.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1418-7) contains supplementary material, which is available to authorized users.

Metabolic and Biochemical Stressors in Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) or diabetes-induced cardiac dysfunction is a direct consequence of uncontrolled metabolic syndrome and is widespread in US population and worldwide. Despite of the heterogeneous and distinct features of DCM, the clinical relevance of DCM is now becoming established. DCM progresses to pathological cardiac remodeling with the higher risk of heart attack and subsequent heart failure in diabetic patients. In this review, we emphasize lipid substrate quality and the phenotypic, metabolic, and biochemical stressors of DCM in the rodent and human pathophysiology. We discuss lipoxygenase signaling in the inflammatory pathway with multiple contributing and confounding factors leading to DCM. Additionally, emerging biochemical pathways are emphasized to make progress toward therapeutic advancement to treat DCM.

Metabolic syndrome and obesity in peritoneal dialysis

Metabolic syndrome (MS) refers to clustering of features related to increased risk of cardiovascular disease, which include obesity or central obesity, dyslipidemia, diabetes mellitus or insulin resistance, together with hypertension. The prevalence of MS in end-stage renal failure patients on peritoneal dialysis is quite common, ranging from 40% to 60%, depending on the population studied and the definition used. However, there are controversies about the clinical outcome of patients with MS, particularly in the area of obesity. Whether peritoneal dialysis predisposes patients to MS is another unsolved issue. Despite these controversies, preventing patients from developing MS is important, at least from a theoretical point of view.

Visceral fat area is associated with HbA1c but not dialysate-related glucose load in nondiabetic PD patients

Factors associated with increased visceral fat area (VFA) have been well documented in the general population but rarely explored in nondiabetic individuals on peritoneal dialysis (PD). As glycosylated hemoglobin (HbA1c) is positively correlated with VFA in diabetic patients, we hypothesized that the same correlation would exist in nondiabetic PD patients. We enrolled 105 nondiabetic patients who had undergone chronic PD for more than 3 months. Each subject underwent an abdominal computed tomography (CT) scan, and the umbilicus cut was analyzed for VFA. VFA values, corrected for body mass index and subjected to natural logarithm transformations, were examined to determine whether they were correlated with HbA1c and other parameters. PD dialysates prescribed at the time of enrollment were recorded to calculate glucose load. We found that when 105 nondiabetic PD patients were classified according to tertiles of HbA1c, higher HbA1c was associated with larger VFA. Multiple linear regression analysis revealed that HbA1c was an independent determinant of VFA, while glucose load and other PD-specific factors were not. In summary, HbA1c, but not PD-related glucose load, was positively correlated with VFA in nondiabetic PD patients, suggesting clinical utility of HbA1c in the PD population.

Alteration of cardiovascular structure and function in patients undergoing peritoneal dialysis

AIMS

Cardiovascular alterations contribute to a high mortality rate in patients with end-stage renal disease (ESRD). The aims of the present study are to evaluate left ventricular (LV) function and common carotid artery (CCA) parameters and to determine risk factors associated with these changes in patients undergoing peritoneal dialysis (PD).

METHODS

This longitudinal prospective study was conducted in 50 ESRD patients in whom PD had been initiated and who were observed for 18 months after the commencement of dialysis treatment, with echocardiography and CCA ultrasound parameter evaluation.

RESULTS

LV hypertrophy was observed in 78% of patients at baseline and in 60% after 18 months of PD treatment. LV systolic and diastolic function was found to be significantly better after 18 months of PD treatment. Examining predictors of LV systolic function, it was found that total cholesterol was an independent positive predictor and endothelin-1 (ET-1) an independent negative predictor of LV systolic function after 18 months of treatment with PD (p < 0.001). Independent negative predictors of diastolic LV function were hemoglobin and type 2 diabetes mellitus, and daily collection of urine was an independent positive predictor (p < 0.001). Female gender was an independent negative predictor of CCA intima-media thickness, whereas body mass index, ET-1 and C-reactive protein were independent positive predictors (p < 0.001).

CONCLUSIONS

The results suggest several novel modifiable mechanisms related to the short-term effects of dialysis that are potentially implicated in the development of uremic cardiomyopathy.

Left ventricular diastolic dysfunction in peritoneal dialysis: a forgotten risk factor

Left ventricular diastolic dysfunction (LVDD) is common among patients undergoing peritoneal dialysis (PD). We examined the relationship between LVDD, major adverse cardiovascular events (MACE), and mortality in PD patients. A total of 149 patients undergoing PD with preserved left ventricular systolic function were included and followed for 3.5 years. LVDD was diagnosed (according to the European Society of Cardiology guidelines) by conventional and tissue Doppler echocardiography. Serum high-sensitivity C-reactive protein (hsCRP) was measured. The location and volume of adipose tissue were assessed by computed tomography (CT) at the level of the fourth lumbar vertebra. Subjects with LVDD had higher levels of hsCRP, and more visceral and peritoneal fat than controls. The relationship between adjusted visceral adipose tissue and LVDD became nonsignificant when hsCRP and baseline demographic data were introduced into the logistic regression model (odds ratio = 1.52, P = 0.07). Subsequent hierarchical multivariate Cox regression analysis showed that LVDD was one of the most powerful determinants of MACE and mortality after adjusting for all confounding factors (hazard ratio [HR]: 1.71, 95% confidence interval [CI]: 1.43-3.51, P = 0.02 and HR: 2.25, 95% CI: 1.45-2.91, P = 0.04, respectively). Systemic inflammation (hsCRP) was also significantly associated with MACE and mortality (HR: 2.03, P = 0.03 and HR: 2.16, P = 0.04, respectively). LVDD is associated with systemic inflammation and increased visceral fat in patients undergoing PD. LVDD is also a sensitive, independent indicator of future MACE and mortality in PD patients.

Metabolic syndrome and abdominal fat are associated with inflammation, but not with clinical outcomes, in peritoneal dialysis patients

Background

In the general population, metabolic syndrome (MetS) is correlated with visceral fat and a risk factor for cardiovascular disease (CVD); however, little is known about the significance of abdominal fat and its association with inflammation and medication use in peritoneal dialysis (PD) patients. We investigated the relationship of visceral fat area (VFA) with C-reactive protein (CRP) levels and medication use in PD patients and followed their clinical outcomes.

Methods

In a prospective study from February 2009 to February 2012, we assessed diabetes mellitus (DM) status, clinical and PD-associated characteristics, medication use, CRP levels, components of MetS, and VFA in 183 PD patients. These patients were categorized into 3 groups based on MetS and DM status: non-MetS (group 1, n = 73), MetS (group 2, n = 65), and DM (group 3, n = 45). VFA was evaluated by computed tomography (CT) and corrected for body mass index (BMI).

Results

Patients in group 1 had smaller VFAs than patients in groups 2 and 3 (3.2 ± 1.8, 4.6 ± 1.9, and 4.9 ± 2.0 cm²/[kg/m²], respectively, P < 0.05) and lower CRP levels (0.97 ± 2.31, 1.27 ± 2.57, and 1.11 ± 1.35 mg/dL, respectively, P < 0.05). VFA increased with the number of criteria met for MetS. After adjusting for age, body weight, and sex, CRP and albumin levels functioned as independent positive predictors of VFA; on other hand, the use of renin-angiotensin system blockers was inversely correlated with VFA in PD patients without DM. In the survival analysis, DM patients (group 3) had the poorest survival among the 3 groups, but no significant differences were found between groups 1 and 2.

Conclusion

This study showed that VFA and MetS are associated with CRP levels but cannot predict survival in PD patients without DM. The complex relationship of nutritional parameters to VFA and MetS may explain these results. The type of antihypertensive medication used was also associated with the VFA. The mechanisms behind these findings warrant further investigation.