Mechanisms of increased vascular superoxide production in human varicose veins.

INTRODUCTION: Varicose vein disease is one of the most common morbidities in the developed countries. Recent studies have shown that oxidative stress is increased in varicose veins (VV) and venous insufficiency. However, the exact mechanisms of oxidative stress in VV remain unknown. OBJECTIVES: The aim of the study was to measure superoxide anion production and analyze its enzymatic sources in VV in comparison with control human saphenous veins (HSV). Superoxide production was also compared between the proximal and distal segments of the veins. PATIENTS AND METHODS: Proximal and distal segments of varicose veins (14 patients, aged 52 ±3.5 years) and control veins (15 patients, aged 56 ±4 years) were obtained during VV removal or elective coronary artery bypass graft surgery, respectively. Subjects were matched for age, sex, and the major risk factors for atherosclerosis. Superoxide was measured by lucigenin-enhanced chemiluminescence (5 µmol/l) in the presence and absence of oxidase inhibitors. RESULTS: Superoxide production was increased in VV compared with control HSV. This increase was particularly evident in the distal segments of VV. There was a significant correlation between superoxide production in the proximal and distal segments of HSV but not of VV. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and uncoupled nitric oxide synthase (NOS) were the major sources of superoxide in VV, because their inhibitors greatly attenuated superoxide production in VV. CONCLUSIONS: NADPH oxidases and NOS could represent valuable drug targets for pharmacological treatment and prevention of varicose vein disease. Oxidative stress may provide a link between endothelial dysfunction, inflammation, and immune activation and the development of chronic venous dysfunction.

Red blood cell rheology in patients with chronic venous disease (CVD).

Rheological studies concerning aggregation and elongation of erythrocytes were carried out in 21 patients (mean age 56 years) with chronic venous disease (CVD) and 10 (mean age 45 years) healthy control subjects, with the use of a LORCA device. Higher values of parameters characterizing both erythrocyte elongation (EI) and aggregation (gammathr) in non-control patients than in the control group were found. These values differed significantly ranging from 1.13 to 8.23 Pa for the shear stress and gammathr in patients--432.14, in relation to the control group--166.5. It was proposed, that the increase in deformability may constitute a compensatory mechanism in subjects with chronic venous disease, due to increased resistance in their microcirculation.

Efficacy and tolerability of liposomal heparin spraygel as an add-on treatment in the management of superficial venous thrombosis.

Superficial venous thrombosis usually resolves spontaneously in a few weeks. In most cases, treatment includes peroral analgesics or nonsteroidal anti-inflammatory drugs accompanied by the recommendation to wear elastic stockings and perform regular mild ambulation. In contrast to this "standard treatment," a recent ACCP guideline has recommended that patients affected by spontaneous superficial thrombophlebitis be treated with intermediate doses of unfractionated or low-molecular-weight heparin. This study was designed to assess the efficacy of topically applied heparin spraygel in terms of reduction of local symptoms and signs of superficial venous thrombosis.

[Surgical site infections following vascular surgery]. / Zakazenia miejsca operowanego po zabiegach w chirurgii naczyniowej.

OBJECTIVE: The aim of this paper was to perform epidemiological and microbiological analyses of surgical site infections diagnosed in patients after vascular surgery in two highly specialist centers in the year 2005. METHODS: The study was conducted in two highly specialist wards in 2005 and covered totally 413 procedures. SSI's detection was based on definitions developed according to CDC guidelines. Post-discharge detection was included in the study. Collected data enabled evaluation of incidence rates and, additionally, in one hospital, assessing detailed rates included standardized SSI risk index. MAIN OBSERVATIONS: Patients underwent analyzed procedures was mainly male (80%), aged 60 and more. In hospital I SSI incidence rate reached 2,6% and in the other (hospital II)--5,6%. Among the etiological factors isolated from patients with SSI staphylococci were the most common (45,5%) and it was mainly Staphylococcus aureus. CONCLUSIONS: The study which was performed showed the incidence of SSIs in patients undergoing vascular surgery at the level of 2.6 and 5.6%. It was shown that it is possible to introduce an effective post-discharge surveillance, which encompassed 50-66% diagnosed cases of SSI.

Red blood cell deformability in patients with claudication after pain-free treadmill training.

OBJECTIVES: To assess the effect of pain-free treadmill training on red blood cell deformability and walking distance in patients with claudication. DESIGN: Randomized-controlled trial of exercise training. SETTING: Patients were recruited from the primary care, vascular outpatient clinic. PATIENTS: A total of 60 patients with peripheral arterial occlusive disease (stage II according to Leriche-Fontaine) were randomized into the treadmill program or a control group. Fifty-five patients completed the study (27 in the exercising group and 28 in the control group). INTERVENTIONS: Patients in the exercising group were walking on the treadmill 3 times a week for 3 months. Each session consisted of 1 hour repetitive walking [performed to 85% of the pain-free walking time (PFWT)] was supervised by a qualified physiotherapist. MAIN OUTCOME MEASUREMENTS: Changes in erythrocyte deformability and treadmill walking performance (PFWT, maximal walking time) were assessed in both groups before the study and after 3 months. RESULTS: After 3 months of treadmill training, red blood cell deformability in the exercising group significantly increased (P<0.01). No significant changes were seen in the erythrocyte deformability in the control group. PFWT was prolonged by 102% from 191+/-34 to 386+/-60 seconds (P<0.01), and maximal walking time increased by 49% from 438+/-62 to 656+/-79 seconds (P<0.01) in the exercising group, whereas these changes were insignificant in the control group. CONCLUSIONS: A significant improvement of walking ability over 3 months of pain-free treadmill training is associated with a significant increase in red cell deformability in patients with claudication.

Experimental model of pain-free treadmill training in patients with claudication.

OBJECTIVE: Treadmill training in claudication is often based on walking exercise to a pain threshold or longer to the maximum muscle pain of the lower limbs. This kind of exercise may cause an inflammatory response. The purpose of this study was to determine whether pain-free treadmill training using walking exercise to 85% of the distance to onset of claudication pain can significantly improve pain-free walking distance in patients with intermittent claudication and to evaluate whether this kind of program may induce an inflammatory response leading to the progression of atherosclerosis. DESIGN: A total of 98 patients aged 50-70 yrs with stable intermittent claudication were randomized into a supervised treadmill training program or a comparison group. Patients in the treatment group participated in 12 wks of supervised treadmill training. We examined the effects of 12 wks of pain-free treadmill training on pain-free walking distance, total leukocyte count, neutrophil count, and microalbuminuria in patients with claudication. RESULTS: A total of 80 participants completed the program. Exercise rehabilitation increased the time to onset of claudication pain by 119.2%, from 87.4 +/- 38 m to 191.6 +/- 94.8 m (P < 0.001). There was no increase in total leukocyte count, neutrophil count, or microalbuminuria after 12 wks of treadmill exercise (P > 0.05) CONCLUSION: A pain-free training program can be used in the treatment of claudication as a low-risk program, increasing walking ability without potential harmful effects of ischemia-reperfusion injury.

Efficacy and safety of the freeze-dried cultured human keratinocyte lysate, LyphoDerm 0.9%, in the treatment of hard-to-heal venous leg ulcers.

LyphoDerm (XCELLentis, Belgium) is an end-sterilized, freeze-dried lysate from cultured allogeneic epidermal keratinocytes, formulated into a hydrophilic gel. Its efficacy and safety were evaluated, in combination with standard care (hydrocolloid dressing and compression therapy), in 194 patients suffering from hard-to-heal (lasting more than 6 weeks and not responding to conventional therapy) venous leg ulcers. Two control groups received standard care, with or without vehicle, respectively. Patients had a median age of 67.5 years and the majority were females (61%). The median duration of the ulcer was 43 weeks and in 39% of the subjects it had been present for more than 1 year. Thirty-eight percent of the patients in the standard care + LyphoDerm group had complete ulcer healing within 24 weeks (primary end point) compared to 27% of patients in the standard care + vehicle pooled groups (P = 0.114) in the "as treated" intent-to-treat cohort (37% vs. 27% in the "as randomized intent-to-treat cohort; p = 0.137). In the subgroup of patients with enlarging ulcers, the difference between the two groups was significant (30% vs. 11%; p = 0.024 in the "as treated" intent-to-treat cohort and 31% vs. 9%; p = 0.005 in the "as randomized" intent-to-treat cohort). LyphoDerm was well tolerated and safe, and no differences in the frequency of adverse events were noted between the treatment groups. Although the primary objective of the study was not achieved, the exploratory analysis carried out in patients with enlarging ulcers suggests that LyphoDerm could offer a new prospect for the treatment of patients with venous ulcers that may prove to be a significant adjunct to the overall provision of care.