Can biomarkers predict myocardial iron overload in children with thalassemia major?

AIM

Beta-thalassemia major requires regular blood transfusions throughout life, which in turn leads to iron accumulation in the body. While cardiac T2* MRI is the gold standard in determining cardiac iron accumulation, it is not always feasible, which has led to the search for new biomarkers. Herein, the value of growth differentiation factor-15, galectin-3, and N-terminal pro-B-type natriuretic peptide in predicting cardiac iron accumulation is investigated in asymptomatic children with beta-thalassemia major.

MATERIALS AND METHOD

Forty-one patients aged 11-21 years and 41 age-, gender-, body mass index-matched healthy controls were included. Serum growth differentiation factor-15, galectin-3, and N-terminal pro-B-type natriuretic peptide levels were compared between the patients and controls. Additionally, the relations of these biomarkers with cardiac and liver T2 * MRI were investigated in the patients.

RESULTS

In the patients, growth differentiation factor-15, galectin-3, and N-terminal pro-B-type natriuretic peptide levels were higher than healthy controls (p < 0.001, p = 0.025, p < 0.001, respectively). There were no significant correlations of growth differentiation factor-15 and N-terminal pro-B-type natriuretic peptide levels with both cardiac and liver T2 * MRI measurements. While there was no significant correlation of serum galectin-3 with cardiac T2 * MRI measurements, a negative correlation was found with liver T2 * MRI measurements (p = 0.040, rho = -0.325).

CONCLUSION

All three biomarkers investigated in this study failed to predict myocardial iron accumulation in asymptomatic children with beta-thalassemia major. However, a weak relation between serum galectin-3 level and hepatic iron accumulation was demonstrated.

Anaemia and Congestion in Heart Failure: Correlations and Prognostic Role

The aim of this study was to evaluate the relationship between anaemia and biomarkers of central/peripheral congestion in heart failure (HF) and the impact on mortality. We retrospectively evaluated 434 acute/chronic HF (AHF/CHF) patients. Anaemia was defined as haemoglobin levels <12 g/dL (women) or <13 g/dL (men). The brain natriuretic peptide (BNP) and hydration index (HI) were measured. The endpoint of the study was all-cause mortality. Anaemia occurred in 59% of patients with AHF and in 35% with CHF (p < 0.001) and showed a significant correlation with the NYHA functional class and renal function. BNP and HI were significantly higher in patients with anaemia than in those without anaemia. Independent predictors of anaemia included BNP, estimated creatinine clearance (eCrCL), and HI. The all-cause mortality rate was 21%, which was significantly higher in patients with anaemia than in those without anaemia (30% vs. 14%, p < 0.001; hazard ratio: 2.6). At multivariate Cox regression analysis, BNP, eCrCL, and HI were independent predictors for mortality (Hazard ratios: 1.0002, 0.97, and 1.05, respectively), while anaemia was not. Anaemia correlates with HF status, functional class, renal function, BNP, and HI. Anaemia was not an independent predictor for mortality, acting as a disease severity marker in congestive patients rather than as a predictor of death.

Assessment of fluid status in neonatal dialysis: the need for new tools

BACKGROUND

Assessment of fluid status in neonatal dialysis has largely focused on traditional tools including clinical assessment, serial weights, and blood pressure (BP) measurements. However, in infants on kidney replacement therapy, the assessment of fluid overload is problematic due to errors in weight assessment, subtlety of physical exam findings, and inaccuracy of non-invasive BP measurements. In this presentation of a neonate with bilateral renal agenesis requiring kidney replacement therapy, the treating team assessed a number of variables in determining the ultrafiltration prescription for dialysis across 2 modalities (hemodialysis and continuous kidney replacement therapy).

COMPLICATIONS

Fluid overload, cardiomegaly, and worsened respiratory status occurred when attempting to assess the neonate's fluid status by traditional markers (weights, blood pressures, physical exam findings). B-type natriuretic peptide (BNP) was obtained and was noted to correlate with the degree of fluid overload.

KEY MANAGEMENT POINTS

Compared to traditional tools for assessment of fluid status in pediatric dialysis, BNP assisted the medical team in optimizing the volume status of the subject and determining optimal daily ultrafiltration goals. Due to the rapid release in response to myocardial stretch and the lack of kidney clearance of the peptide, BNP may represent an objective, timely, and reliable index of volume status in the pediatric dialysis patient.

Association of N-terminal pro-brain natriuretic peptide with contrast-induced acute kidney injury and long-term mortality in patients with heart failure and mid-range ejection fraction: An observation study

The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF.A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively.The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9-7470.5] vs 1303[625.2-2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18-51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16-65.70; P = 0.004) during follow-up.In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary angiography or intervention.

Amino-terminal pro-brain natriuretic peptide in children with latent rheumatic heart disease

Background:

Rheumatic heart disease (RHD) is a global cause of early heart failure. Early RHD is characterized by valvar regurgitation, leading to ventricular distention and possible elaboration of amino-terminal pro-brain natriuretic peptide (NT-proBNP). We investigated the ability of NT-proBNP to distinguish cases of latent RHD detected by echocardiographic screening from the controls.

Materials and Methods:

Ugandan children (N = 44, 36% males, mean age: 12 ± 2 years) with latent RHD (cases) and siblings (controls) by echocardiography were enrolled. Cases and controls were matched for age and sex, and they had normal hemoglobin (mean: 12.8 mg/dL). Children with congenital heart disease, pregnancy, left ventricular dilation or ejection fraction (EF) below 55%, or other acute or known chronic health conditions were excluded. RHD cases were defined by the World Heart Federation (WHF) 2012 consensus guideline criteria as definite. Controls had no echocardiography (echo) evidence for RHD. At the time of echo, venous blood samples were drawn and stored as serum. NT-proBNP levels were measured using sandwich immunoassay. Paired t-tests were used to compare NT-proBNP concentrations including sex-specific analyses.

Results:

The mean NT-proBNP concentration in the cases was 105.74 ± 67.21 pg/mL while in the controls, it was 86.63 ± 55.77 pg/mL. The cases did not differ from the controls (P = 0.3). In sex-specific analyses, male cases differed significantly from the controls (158.78 ± 68.82 versus 76 ± 42.43, P = 0.008). Female cases did not differ from the controls (75.44 ± 45.03 versus 92.30 ± 62.35 respectively, P = 0.4).

Conclusion:

Serum NT-proBNP did not distinguish between latent RHD cases and the controls. Sex and within-family exposures may confound this result. More investigation into biomarker-based RHD detection is warranted.

Amino-terminal pro-brain natriuretic peptide as a prognostic marker in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with increased cardiovascular (CV) morbidity and mortality, of which amino-terminal pro-brain natriuretic peptide (NT-proBNP) is a predictor. The objective of the study was to investigate associations between NT-proBNP and age, gender, markers of inflammation, disease activity, and kidney function in RA patients, without co-morbidities potentially influencing NT-proBNP concentration. The study group consisted of 90 patients with RA, without clinically relevant coronary heart disease, hypertension, diabetes, advanced chronic kidney disease. The comprehensive assessment of clinical and laboratory parameters of inflammation, disease activity, and kidney function was performed. Plasma samples were frozen for NT-proBNP analysis. Carotid intima media thickness (cIMT) was determined by high-resolution B-mode ultrasonography. The mean NT-proBNP concentrations were significantly higher in a group of RA patients with high disease activity (DAS28 > 5.1) and in a group of patients with subclinical atherosclerosis diagnosed by cIMT ≥ 0.6 mm. In all RA patients, NT-proBNP correlated positively with the age, C-reactive protein, erythrocyte sedimentation rate, cIMT, tricipital skin fold and negatively with hand-grip strength, hemoglobin, red blood cell count, albumin. In the group of women with RA, we found significant positive correlation between NT-proBNP and cystatin-C. Also, patients with NT-proBNP level ≥ 100 pg/ml had significantly higher cystatin-C than those with lower NT-proBNP. NT-proBNP level, in RA patients without co-morbidities potentially influencing this level, is correlated with age, disease activity markers of inflammation, and subclinical renal impairment. It means that risk of CV disorders is higher in older patients with more active RA.

Correlates of NT-proBNP concentration in patients with essential hypertension in absence of congestive heart failure

BACKGROUND

N-terminal proBNP (NT-proBNP) is widely used as a diagnostic biomarker and for the risk stratification of patients with heart failure (HF). Its role in the evaluation of patients with essential hypertension (EHT) is less clear. We examined the relationship between NT-proBNP concentrations and various clinical characteristics in hypertensive patients without HF.

METHODS

This study included 186 consecutive patients with EHT and no history of HF, ischemic heart disease, or atrial fibrillation. Single and multiple variable regression analyses were performed in search of clinical correlates of NT-proBNP concentrations.

RESULTS

In patients with EHT, median serum concentration of NT-proBNP was 73 pg/ml, and interquartile range (IQR) was 40-128 pg/ml. NT-proBNP was significantly higher (P<0.001) in women (87 pg/ml; IQR 55-137 pg/ml) than in men (52 pg/ml; IQR 24-115 pg/ml). Age (r=0.371, P<0.001), precordial QRS voltage (r=0.223, P<0.001), hemoglobin (Hgb) concentration, (r=-0.208, P=0.023) and estimated glomerular filtration rate (r=-0.139, P=0.044) were correlated with log-transformed NT-proBNP by multiple variable analysis. In men, age (r=0.453, P<0.001) and QRS voltage (r=0.283, P=0.004), and in women age (r=0.299, P=0.006), QRS voltage (r=0.212, P=0.019), Hgb (r=-0.182, P=0.049), and estimated glomerular filtration rate (r=-0.272, P=0.009) were correlated with serum concentrations of NT-proBNP.

CONCLUSIONS

Age, gender, Hgb, left ventricular hypertrophy and renal function were correlated with NT-proBNP in patients with EHT.

N-terminal ProBNP distribution and correlations with biological characteristics in apparently healthy Greek population: ATTICA study

Brain natriuretic peptides are widely used as biomarkers of cardiovascular diseases and mainly heart failure. However, these markers are often found to be high even in apparently healthy participants, and little is known about which factors contribute to physiological change in plasma brain natriuretic peptide (BNP) and amino-terminal pro-B-type natriuretic peptide (NTproBNP) concentration in general populations. In this study, a random subsample of the ATTICA study was used (486 individuals) and serum NT-proBNP was measured. Approximately 20% of the participants had no detectable NT-proBNP values. Women had higher values of NT-proBNP than men (median [25th-75th percentiles]: 30.2 [15.8-54.3] vs 14.9 [4.0-28.1] pg/mL, P < .001]. Amino-terminal pro-B-type natriuretic peptide values were positively correlated with age (rho = .140, P = .006) and inversely with body mass index (BMI; rho = -.142, P = .005), creatinine (Cr) clearance (rho = -.349, P < .001), and hemoglobin (rho = -.249, P < .001) values. Linear regression analysis revealed that gender is the main contributor of NT-proBNP levels, followed by age, BMI, and Cr values.