Effects of lowered dialysate sodium on left ventricle function and brain natriuretic peptide in maintenance of hemodialysis patients.

INTRODUCTION: Impaired diastolic flow is characterized by decreased left ventricular (LV) filling diastole, abnormal LV distensibility, or delayed relaxation. B-Type natriuretic peptide (BNP) is an indicator of various cardiovascular diseases and body volume status. The aim of this study was to determine whether the lowering of dialysate sodium (Na) levels is effective on LV systolic and diastolic parameters and BNP in the maintenance of hemodialysis patients. MATERIALS AND METHODS: The study included 49 chronic hemodialysis patients. Left atrium (LA) diameter and LV ejection fraction, LV systolic and diastolic diameter, deceleration time (DT), pulmonary artery pressure (PAP), inferior vena cava diameter (IVCD), early diastolic transmitral flow ( E) and late diastolic transmitral flow ( A) velocities, E/ A ratio, isovolumic relaxation time, peak early diastolic velocity ( E'), late diastolic velocity ( A') of tissue Doppler mitral annulus, and flow propagation velocity of mitral inflow ( Vp) were measured before and 6 months after hemodialysis with low Na dialysate. RESULTS: Six months after low Na hemodialysis, a decrease was observed in echocardiographic parameters such as PAP and IVCD ( p < 0.05, p < 0.001, and p < 0.001, respectively). However, a significant difference was not observed in LA diameter. In LV diastolic measurement of E and A waves, E/ A ratio, DT, Vp, septal E' and A', and lateral E' and A' exhibited significant improvement by low Na HD. BNP level was significantly reduced ( p < 0.001). CONCLUSIONS: Lowered dialysate Na concentration improves PAP, IVCD, and LV diastolic properties assessed by mitral inflow filling, tissue Doppler velocity, and mitral inflow velocity propagation.

A new echocardiographic parameter of arterial stiffness in end-stage renal disease.

BACKGROUND: Cardiovascular disease is the leading cause of death among patients with end-stage renal disease (ESRD). Arterial stiffness is an independent predictive parameter of overall and cardiovascular mortality in these patients. However, the defined procedures for the measurement of arterial stiffness are time consuming and not practical in daily practice. METHODS: The study population included 50 patients with ESRD who were treated with hemodialysis (HD; n=23) or peritoneal dialysis (PD; n=27) and 70 age- and sex-matched control subjects. Aortofemoral pulse wave velocity (PWV), carotid intima-media thickness (CIMT), and color M-mode propagation velocity of the descending aorta (aortic propagation velocity, APV) were measured. RESULTS: Compared to the control group, the patients with ESRD had significantly lower APV (46.4 ± 12.4 vs. 58.5 ± 8.5, p < 0.01) and higher PWV (10.5 ± 2.5 vs. 9.2 ± 1.2, p < 0.01) and CIMT (0.66 ± 0.15 vs. 0.43 ± 0.06, p < 0.01) measurements. There were significant correlations between APV and CIMT (r = - 0.769, p < 0.001), APV and PWV (r = - 0.682, p < 0.001), and PWV and CIMT (r = 0.564, p < 0.001). There were no significant differences in APV and PWV between the PD and HD patients. CONCLUSION: Arterial stiffness is an important indicator of atherosclerosis and arterial aging in patients with ESRD. The measurement of APV is an easy and practical new echocardiographic method and may be used to identify arterial stiffness in these patients.

A novel echocardiographic method as an indicator of endothelial dysfunction in patients with coronary slow flow.

BACKGROUND: To improve clinical outcomes, noninvasive imaging modalities have been proposed to measure and monitor atherosclerosis. Endothelial dysfunction is considered the first stage in the development of atherosclerosis. Brachial artery flow-mediated dilatation (FMD) has been impaired in patients with coronary slow flow (CSF). Recently, color M-mode derived propagation velocity of descending thoracic aorta (aortic propagation velocity-AVP) was shown to be an ultrasonographic marker for atherosclerosis. AIM: To assess endothelial function in patients with CSF and the correlation of AVP with FMD. MATERIALS AND METHODS: FMD and AVP were measured in 90 patients with CSF and 39 patients having normal coronary arteries (NCA) detected by coronary angiography. RESULTS: Compared to patients with normal coronary arteries patients having CSF had significantly lower AVP (39.1±8.4 vs. 53.7±12.7 cm/s, p < 0.001) and FMD (5.6±3.2 vs. 17.6±4.4 %, p < 0.001) measurements. There were significant correlations between AVP and FMD (r = 0.524, p < 0.001). CONCLUSIONS: Transthoracic echocardiographic determination of color M-mode propagation velocity of descending aorta is a simple practical method and correlates well with coronary slow flow and brachial endothelial function.

Short-term levosimendan treatment protects rat testes against oxidative stress.

The objective of this study was to evaluate the effect of short-term levosimendan exposure on oxidant/antioxidant status and trace element levels in the testes of rats under physiological conditions. Twenty male Wistar albino rats were randomly divided into two groups of 10 animals each. Group 1 was not exposed to levosimendan and served as control. Levosimendan (12 µg/kg) diluted in 10 mL 0.9% NaCl was administered intraperitoneally to group 2. Animals of both groups were sacrificed after 3 days and their testes were harvested for the determination of changes in tissue oxidant/antioxidant status and trace element levels. Tissue malondialdehyde (MDA) was significantly lower in the levosimendan group (P < 0.001) than in the untreated control group and superoxide dismutase and glutathione peroxidase (GSH-Px) levels were significantly higher in the levosimendan group (P < 0.001). Carbonic anhydrase, catalase and GSH levels were not significantly different from controls. Mg and Zn levels of testes were significantly higher (P < 0.001) and Co, Pb, Cd, Mn, and Cu were significantly lower (P < 0.001) in group 2 compared to group 1. Fe levels were similar for the two groups (P = 0.94). These results suggest that 3-day exposure to levosimendan induced a significant decrease in tissue MDA level, which is a lipid peroxidation product and an indicator of oxidative stress, and a significant increase in the activity of an important number of the enzymes that protect against oxidative stress in rat testes.

Role of echocardiography in the evaluation of atrial function and diseases.

This article describes four essential components (hemodynamic, bioelectrical, hormonal and metabolic) of atrial function. And then discusses the traditional and more recent echocardiographic measures that have been employed to evaluate atrial function. Conventional parameters include the study of the various phases of atrial activity using atrial volume measurements, the peak A wave velocity, its velocity time integral (VTI), fraction of atrial contribution and atrial ejection force. Newer parameters for atrial function assessment include Doppler tissue imaging (DTI) including segmental atrial contractility using color Doppler tissue imaging (CDTI) and estimates of atrial strain and strain rate. Furthermore, the authors relate various particular types of atrial function in physiological and in selected pathological conditions.