losartan-potassium and Constriction--Pathologic

Among the adverse effects possibly associated with the use of erythropoietin (EPO) in hemodialysis patients is an increased incidence of thrombosis of the vascular access. However, little is known about the effect of EPO on the stenotic lesion in the venous outflow system, which is the leading cause of fistula thrombosis. This study was designed to explore the long-term effects of EPO treatment on progressive fistula stenosis and the plasma concentrations of some potential mediators of neointimal hyperplasia. A cross-sectional and 3-yr prospective, placebo-controlled, pilot study was performed in 30 hemodialysis patients with native arteriovenous fistula. Sixteen patients received EPO and 14 received a placebo. Venous dialysis pressure, urea recirculation, color Doppler sonography, and angiography were used to monitor vascular access patency. Compared with 60 healthy subjects, the hemodialysis patients had elevated plasma levels of platelet-derived growth factor, monocyte chemoattractant protein-1, and interleukin 6, three proteins that might be involved in the neointima formation regulating the proliferation of vascular smooth muscle cells. In addition, these patients had numerous endothelial and hemostatic abnormalities that indicated a thrombophilic state. Eleven patients, six (37.5%) receiving EPO and five (35.7%) taking placebo, developed a progressive stenosis in the venous circuit of the fistula. There was no significant difference in the vascular access, event-free survival over 36 mo between patients receiving EPO therapy and placebo. EPO induced a significant decrease in the plasma values of platelet-derived growth factor and vascular cell adhesion molecule-1 and an increase of monocyte chemoattractant protein-1 concentration. After EPO withdrawal, these parameters returned to pretreatment levels. In conclusion, long-term EPO therapy does not increase the risk of progressive stenosis of native arteriovenous fistula. The use of erythropoietin does not induce any prothrombotic change in hemostatic parameters, and further studies are required to elucidate the theoretically beneficial effects on the plasma concentration of some potential mediators of neointimal formation.

Topics: Adult; Aged; Apolipoproteins; Arteriovenous Shunt, Surgical; Cell Adhesion Molecules; Chemokine CCL2; Constriction, Pathologic; Cross-Sectional Studies; Cytokines; Erythropoietin; Female; Fibrinolysis; Hemostasis; Humans; Kidney Failure, Chronic; Lipids; Male; Middle Aged; Platelet-Derived Growth Factor; Prospective Studies; Renal Dialysis; Thrombophlebitis

A native AV-fistula (AVF) for access in hemodialysis (HD) is preferable. Stenosis, a major hurdle, is associated with older age and diabetes mellitus.. This case-control study aimed to clarify if any medical and/or laboratory factors, that can be altered, could be associated to AVF stenosis.. 33 patients with a patent AVF without need of intervention during a two year period (Controls) were matched by diagnosis and age with 33 patients (Cases), that had at least one radiological invasive examination/intervention due to suspected AVF malfunction (case-control mode 2:1).. Cases had higher weekly doses of Erythropoietin-Stimulating Agent (ESA) than Controls both before intervention (mean 8312±7119 U/w versus 4348±3790, p = 0.005) and after the intervention (7656±6795, versus 4477±3895, p = 0.018). Before intervention serum phosphate was higher in Cases while there was no significant difference in blood hemoglobin, weekly standard Kt/V, parathyroid hormone, calcium, albumin, C-reactive protein, smoking habits, BMI or other medication.. Higher doses of ESA were administered in patients with AVF stenosis. Since ESA may cause local hypertrophic effects on the vascular endothelium, we should prescribe lower doses of ESA in patients at risk. Further studies should clarify such connection.

Topics: Arteriovenous Fistula; Case-Control Studies; Constriction, Pathologic; Erythropoietin; Female; Humans; Male; Renal Dialysis; Risk Factors

To measure the serum erythropoietin (EPO) level in patients with saphenous vein grafts (SVGs) and to compare the EPO level in those with and without SVG disease.. The study included 85 consecutive patients with a history of coronary artery bypass graft surgery that underwent elective coronary angiography. Patients with >30% stenosis (diseased grafts) in at least one saphenous graft were included in group 1 (diseased group: n = 40), and group 2 (nondiseased group: n = 45) consisted of patients without diseased SVGs. The EPO level was measured using enzyme-linked immunosorbent assay (ELISA) using a commercially available ELISA kit; x03C7;2 test and independent samples t test were used where appropriate. Logistic regression was used for multivariate analysis.. There were not any significant differences in age, gender, or cardiovascular risk factors between the two groups except for increased triglyceride and low high-density lipoprotein levels in group 2. The EPO level was significantly higher in the nondiseased SVG group than in the diseased SVG group (25.5 ± 9.6 vs. 17.8 ± 6.8 mU ml-1, p = 0.002). Multivariate logistic regression analysis showed that the serum EPO level was an independent predictor of SVG disease (OR 1.14, 95% CI 1.06-1.24, p = 0.001).. In this study, SVG disease was associated with a low serum EPO level, suggesting that a low EPO level could be predictive of and contributes to the pathophysiology of SVG disease.

Topics: Adult; Aged; Aged, 80 and over; Comorbidity; Constriction, Pathologic; Coronary Angiography; Coronary Artery Bypass; Enzyme-Linked Immunosorbent Assay; Erythropoietin; Female; Humans; Logistic Models; Male; Middle Aged; Risk Factors; Saphenous Vein

We aimed to evaluate possible effects of erythropoietin on the healing of anastomosis in both obstructive and non-obstructive states. It was an experimental study on guinea pigs. Although erythropoietin had positive effects on pressure in the group IV when compared to the group II, it had no effect in the group III. Despite an increased tissue hydroxyproline levels in the group IV, erythropoietin failed to show any effects in the group III. Erythropoietin had positive effects on neovascularization, fibroblast proliferation and storage of collagen in the group IV. We failed to find any direct and evident effects of erythropoietin on the healing of left colonic anastomosis. On the other hand, erythropoietin might prevent negative effects of obstruction on healing (Tab. 2, Fig. 4, Ref. 33).

Topics: Anastomosis, Surgical; Animals; Colon; Constriction, Pathologic; Erythropoietin; Guinea Pigs; Male; Recombinant Proteins; Wound Healing

1. We investigated the effects of recombinant human erythropoietin (rh-EPO) in splanchnic artery occlusion (SAO) shock. Sham operated animals were used as controls. Survival rate, mean arterial blood pressure (MAP), serum Tumor Necrosis Factor (TNF-alpha), plasma nitrite/nitrate concentrations, red blood cell (RBC) count, blood haemoglobin (Hb), the responsiveness of aortic rings to phenylephrine (PE, 1 nM-10 microM) and the activity of inducible nitric oxide synthase (iNOS) were studied. 2. SAO shocked rats had a decreased survival rate (0% at 4 h of reperfusion, while sham shocked rats survived more than 4 h), enhanced serum TNF-alpha concentrations, increased plasma nitrite/nitrate levels (60+/-9.5 microM; sham shocked rats= 2+/-0.4 microM), decreased MAP, unchanged RBC count and blood Hb and enhanced iNOS activity in the aorta. Moreover aortic rings from shocked rats showed a marked hyporeactivity to PE. 3. Rh-EPO (25, 50 and 100 U 100 g(-1), 5 min following the onset of reperfusion) increased survival rate (70% at 4 h of reperfusion with the highest dose), reduced plasma nitrite/nitrate concentrations (10.3+/-3.3 microM), increased MAP, did not change RBC count and blood Hb, and inhibited iNOS activity in thoracic aortae. Furthermore rh-EPO, either in vivo or in vitro (10 U for 1 h in the organ bath), restored to control values the hyporeactivity to PE. Finally rh-EPO inhibited the activity of iNOS in peritoneal macrophages activated with endotoxin. 4. Our data suggest that rh-EPO protects against SAO shock by inhibiting iNOS activity.

Topics: Animals; Aorta, Thoracic; Blood Pressure; Constriction, Pathologic; Enzyme Inhibitors; Erythrocyte Count; Erythropoietin; Humans; In Vitro Techniques; Male; Muscle Contraction; Muscle, Smooth, Vascular; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Shock; Splanchnic Circulation; Survival Analysis; Tumor Necrosis Factor-alpha