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P Poredos

Publications and source records attributed to P Poredos.

23 records · Page 2Linked to original sources
PubMed1996

Plasma viscosity increase with progression of peripheral arterial atherosclerotic disease.

Increased blood and plasma viscosity has been described in patients with coronary and peripheral arterial disease. However, the relation of viscosity to the extent of arterial wall deterioration--the most important determinant of clinical manifestation and prognosis of the disease--is not well known. Therefore, the authors studied plasma viscosity as one of the major determinants of blood viscosity in patients with different stages of arterial disease of lower limbs (according to Fontaine) and its relation to the presence of some risk factors of atherosclerosis. The study encompassed four groups of subjects: 19 healthy volunteers (group A), 18 patients with intermittent claudication up to 200 m (stage II; group B), 15 patients with critical ischemia of lower limbs (stage III and IV; group C), and 16 patients with recanalization procedures on peripheral arteries. Venous blood samples were collected from an antecubital vein without stasis for the determination of plasma viscosity (with a rotational capillary microviscometer, PAAR), fibrinogen, total cholesterol, alpha-2-macroglobulin, and glucose concentrations. In patients with recanalization procedure local plasma viscosity was also determined from blood samples taken from a vein on the dorsum of the foot. Plasma viscosity was most significantly elevated in the patients with critical ischemia (1.78 mPa.sec) and was significantly higher than in the claudicants (1.68 mPa.sec), and the claudicants also had significantly higher viscosity than the controls (1.58 mPa.sec). In patients in whom a recanalization procedure was performed, no differences in systemic and local plasma viscosity were detected, neither before nor after recanalization of the diseased artery. In all groups plasma viscosity was correlated with fibrinogen concentration (r=0.70, P < 0.01) and total cholesterol concentration (r=0.24, P < 0.05), but in group C (critical ischemia) plasma viscosity was most closely linked to the concentration of alpha-2-macroglobulin (r=0.78, P < 0.01). These results indicate that in patients with peripheral arterial disease plasma viscosity increases with the progression of the atherosclerotic process and is correlated with the clinical stages of the disease.

Aged↗
PubMed1993

Double-blind, controlled, multicenter study of indobufen versus placebo in patients with intermittent claudication.

The objective of the study was to evaluate the efficacy and safety of indobufen compared with placebo in the treatment of moderately severe intermittent claudication. The study consisted of a four-week single-blind, placebo-controlled run-in phase, followed by a six-month double-blind randomized treatment period. A total of 302 patients were allocated to treatment with either placebo (154 patients) or indobufen (148) 200 mg twice daily. The results of the overall intention-to-treat analysis of the study population showed statistically significant superiority of indobufen over placebo after six months for both the initial (ICD) and absolute claudication distances (ACD). The ICD before treatment with indobufen or placebo averaged 137.9 +/- 68.2 and 136.6 +/- 63.2 m (mean +/- SD), respectively. After six months' treatment with active drug or placebo, this parameter reached 227.9 +/- 174.4 and 153.1 +/- 86.8 m (mean +/- SD), respectively (p < 0.01). Similar results were obtained on ACD. The reduction of lower limb symptoms also suggested a greater clinical benefit in the indobufen-treated patients. There was no significant change in either group in the ankle/arm pressure ratio at the end of treatment. Adverse events of any type were reported by 18 patients (12.2%) in the indobufen group and by 11 patients (7.2%) in the placebo group. The mechanism whereby the drug is effective in this clinical condition could be related to both its antiplatelet and hemorheologic effects.

Double-Blind Method↗
PubMed1989

Late results of local thrombolytic treatment of peripheral arterial occlusions.

One hundred thirty-four patients, in whom acute and subacute arterial occlusions of lower limbs were treated with low dose intraarterial streptokinase, were observed for periods of up to five years. Primary recanalization of occluded vessels was achieved in 66 patients, but in the remaining 68 patients recanalization was not observed. In 45% of the patients with successful thrombolytic treatment, percutaneous dilatation (PTA) of remnant stenosis was performed. In patients with successful recanalization the reocclusion rate was greatest in the first year (17.4%); the first two weeks after therapy were most critical in this respect. The reocclusion rate during the succeeding years ranged from 4% to 9% per year. The cumulative patency rate after five years was 63.4%. Late results were better in patients in whom more proximal vascular segments were affected. The preservation of vessel patency was highly dependent on the severity and extent of the previous atherosclerotic process and especially on the state of peripheral (runoff) arteries. Presence of diabetes mellitus increased the reocclusion rate of recanalized vessels. Of the patients with unsuccessful recanalization, only 5 reported some symptomatic improvement during the observation period, 39 (57%) needed immediate amputation, and an additional 8 (4.7%) were amputated later on. Considering the fact that all patients were previously refused for bypass surgery owing to unsuitable runoff vessels or bad general condition, the long-term results were surprisingly good, suggesting that thrombolytic treatment, combined in remnant stenosis with PTA, was an efficient method in patients with acute or subacute arterial occlusions.

Adult↗
PubMedDate not supplied

Endothelial dysfunction and cardiovascular disease.

Healthy endothelium plays a central role in cardiovascular control. Therefore endothelial dysfunction (ED), which is characterized by an imbalance between relaxing and contracting factors, procoagulant and anticoagulant substances, and between proinflammatory and antiinflammatory mediators, may play a particularly significant role in the pathogenesis of atherosclerosis and cardiovascular disease. ED is thought to be an early physiologic event in the development of atherosclerosis, occurring before morphologic changes in the vessel wall can be detected. It is closely related to different risk factors of atherosclerosis, to their intensity and their duration. The involvement of risk factors in ED is also supported by results of intervention studies that showed regression of ED with treatment of risk factors. Further, it was shown that ED is significantly and directly correlated with the occurrence of cardiac events. The common denominator whereby different risk factors cause ED is most probably increased oxidative stress and consequently decreased bioavailability of nitrogen oxide. Endothelial dysfunction promotes atherosclerosis and probably plays an important role in the development of thrombotic complications in late stages of the disease. As ED is a key underlying factor in the atherosclerotic process, markers of endothelial abnormalities have been proposed, but loss of endothelium-dependent vasodilation has became a broadly accepted indicator of endothelial dysfunction. Using these non-invasive tests it is possible to follow the dose-response of harmful effects or risk factors, and the effects of preventive procedures on vessel wall function.

Arteriosclerosis↗