The International Journal of Artificial Organs

There is a strong association between chronic kidney disease (CKD) and cardiovascular events. Increased arrhythmia risk in kidney disease is one of the main predominant factors in increased mortality and sudden cardiac death. To estimate this risk, noninvasive measurement of repolarization abnormalities including QT interval and its heart rate-corrected value (QTc) with surface ECG, are commonly used parameters in clinical practice. The aim of this study is to examine the effect of CKD-related problems – mainly acidosis – on QT intervals.

30 patients with stage 3–5 CKD whose serum bicarbonate concentrations below 20 mmol/L were included in the study. Alkali therapy with oral sodium bicarbonate was used to maintain the serum bicarbonate concentration in the normal range. At the beginning all patients had sinus rhythm on surface ECG records. Kidney function tests including serum urea, serum creatinine, uric acid, blood gas analysis, and electrolytes were analyzed at the beginning and at the end of alkali treatment. All patients underwent 12 lead-ECGs, recorded simultaneously. One cardiologist examined the ECGs manually in terms of QT intervals, corrected for heart rate (QTc), QT dispersion (QTd) and corrected QT dispersion (QTcd).

There were statistically significant differences in QT intervals, QTc, QTd and QTcd before and after sodium bicarbonate treatment. The correlation analyses revealed that there were significant negative correlations in pretreatment ECGs of patients between QTd and QTcd with blood pH level. Multivariate analyses between biochemical parameters and QTd-QTcd intervals have revealed that pH was related to QTd and QTc.

This study demonstrated that QT intervals on surface ECG are decreased after treatment of acidosis in CKD. Further studies are needed to show whether increased QT intervals cause ventricular arrhythmias in CKD.

Midkine (MK), which is expressed in the proximal tubular epithelial cells of the kidney, is thought to have a role in the pathophysiology of inflammation-related renal diseases. Both immunological and nonimmunological mechanisms may affect renal functions negatively during the early and late post-transplantation periods. We aimed in our study to evaluate the relationship of MK with clinical findings and inflammatory markers, including high sensitivity C-reactive protein (hs-CRP), interleukin (IL-6) and tumor necrosis factor (TNF-α) in the pretransplant and post-transplant period.

Forty-one consecutive patients transplanted from living related donors were included in this prospective observational study. All patients received the same immunosuppressive treatment protocol. MK, hsCRP, IL-6 and TNF-α levels were measured before and 2 months after renal transplantation.

Pretransplant MK levels correlated positively with hsCRP (r = 0.41, p = 0.004) and IL-6 (r = 0.58, p<0.001). The mean post-transplant MK level was found to be higher than the pretransplant level (143 ± 350 pg/mL, 2792 ± 4235 pg/mL respectively, p = <0.001), while the mean hsCRP, IL-6 and TNF-α levels did not change significantly. Post-transplant IL-6 correlated significantly with MK (r = 0.388, p = 0.012), hsCRP (r = 0.41, p = 0.007) and TNF-α (r = 0.348, p = 0.026). There was no significant correlation between clinical findings and inflammatory markers.

MK may be a good inflammatory marker in renal transplant recipients as in other inflammatory diseases. Moreover, it seems that it is not affected by factors other than inflammation during the post-transplantation period.

Many dialysis centres have no formal program for assessing and adjusting post-haemodialysis (HD) target weight. Apart from clinical assessment, there are bioimpedance devices and natriuretic peptides that could potentially aid clinical management. We wished to determine whether pre- or post-HD bioimpedance assessment of extracellular water (ECW) or N terminal probrain natriuretic peptide (NT-proBNP) affected patient outcomes.

Multi-frequency bioimpedance assessments (MFBIA) were made before and after the midweek dialysis session, along with a post-dialysis NT-proBNP measurement.

Data from 362 patients, median age of 63 (50–76) years, 59.7% male, 41.2% Caucasoid, with a median dialysis vintage of 31.4 (13.5–61.7) months were available for review. During a median follow-up of 49.6 (21.9–50.2) months there were 110 (30.4%) deaths. Patients who died had significantly increased ECW, as % over-hydrated both pre-HD 6.6 (5.8–7.6)% vs. survivors 5.1 (4–6.6)%, and post-HD 5.1 (4–6.6)% vs. 0.5 (-1-2.2.0, p<0.001, respectively. They also had higher NT-proBNP 325 (122–791) vs. 102 (48–342) pmol/l, p = 0.002. Using an adjusted Cox model, pre-HD ECW overhydration remained an independent factor associated with mortality (overhydration %: hazard ratio 1.15, 95% limits 1.03–1.28, p = 0.013), with a receiver operator curve (ROC) value of 0.7.

ECW excess is associated with increased mortality for HD patients, with ECW excess pre-dialysis being the strongest association, although these patients also had increased ECW post dialysis. Future trials are required to determine whether achieving euvolaemia as determined by bioimpedance improves patient survival.

Extracorporeal membrane oxygenation (ECMO) has been proven effective in life support for patients with refractory cardiopulmonary failure. Deteriorating patients who have removed their first ECMO support and required second or more courses of ECMO support have rarely been discussed.

All the records of the patients who experienced at least 2 courses of ECMO during single admission were retrieved. Survival was defined as survival to discharge. Demographic data and clinical information were compared between survival and nonsurvival groups. There were 86 patients who received at least 2 courses of ECMO in the 20-year database, and 27 (31.3%) were <18 years old. Of them, 87.3% received 2 runs of ECMO, 10.4% 3 runs, and 2.3% 4 runs. Overall survival rate was 30.2%. The survival rate for patients with 2 runs of ECMO was 33.3% (25 out of 75), 11.1% (1 out of 9) for 3 runs, and 0% (0 out of 2) for 4 runs. Multivariate analysis revealed that only ARF with hemodialysis was the independent risk factor.

The decision to perform repeated ECMO implantation is a complex and difficult process. Despite the arguments debating the consumption of resources and increased complications, there are still nearly 1 out of 3 patients who will survive to discharge. More than 2 courses of ECMO may be carefully considered for further rescue.

In recent years, the extremely low frequency electromagnetic field (ELF-EMF) has attracted a great deal of scientific interest. The ELF-EMF signal is able to control ion transport across ion channels and therefore induce cell differentiation.

The purpose of this study was to investigate the effect of ELF-EMF (50 Hz, 1 mT) on MAP2 and Nestin gene expression of dermal papilla mesenchymal cells (DPCs).

In order to examine the effect of chemical and electromagnetic factors on gene expression, 4 experimental groups, namely chemical (cell exposure to chemical signals), EMF (exposing cells to ELF-EMF), chemical-EMF (subjecting cells to chemical signals and ELF-EMF) and control (with no treatment) groups, were prepared, treated for 5 days, and studied. To assess the effect of extended test time on the expression of neural differentiation markers (Nestin and MAP2), an EMF group was prepared and treated for a period of 14 consecutive days. The beneficial role of EMF in inducing neural differentiation was shown by real-time PCR analysis.

The higher expression of MAP2 after 14 days compared to that after 5 days and decrease of cell proliferation on days 5 to 20 were indicative of the positive effect of extending treatment time on neural differentiation by evaluation of gene expression in EMF group.