Clinical, ultrasonographic and histological findings in varicose vein surgery

SUMMARY OBJECTIVE This study aims to correlate the demographic data, different clinical degrees of chronic venous insufficiency (CEAP), ultrasound findings of saphenofemoral junction (SFJ) reflux, and anatomopathological findings of the proximal segment of the great saphenous vein (GSV) extracted from patients with primary chronic venous insufficiency (CVI) submitted to stripping of the great saphenous vein for the treatment of lower limb varicose. METHOD This is a prospective study of 84 patients (110 limbs) who were submitted to the stripping of the great saphenous vein for the treatment of varicose veins of the lower limbs, who were evaluated for CEAP clinical classification, the presence of reflux at the SFJ with Doppler ultrasonography, and histopathological changes. We study the relationship between the histopathological findings of the proximal GSV withdrawal of patients with CVI with a normal GSV control group from cadavers. RESULTS The mean age of the patients was higher in the advanced CEAPS categories when comparing C2 (46,1 years) with C4 (55,7 years) and C5-6(66 years), as well as C3 patients (50,6 years) with C5-6 patients. The normal GSV wall thickness (mean 839,7 micrometers) was significantly lower than in the saphenous varicose vein (mean 1609,7 micrometers). The correlational analysis of reflux in SFJ with clinical classification or histopathological finding did not show statistically significant findings. CONCLUSIONS The greater the age, the greater the clinical severity of the patients. The GSV wall is thicker in patients with lower limb varicose veins, but those histopathological changes are not correlated with the disease’s clinical severity or reflux in the SFJ on a Doppler ultrasound.

The Effects of Heparin on Cultured Explants of Varicose Long Saphenous Vein

Objective:

To examine the effects of heparin on smooth muscle cells (SMCs) in explants of varicose, long saphenous vein (LSV).

Procedures:

Explants of varicose LSV were cultured for 7 days either alone, or with heparin at 10, 100 or 1000 IU/ml (Monoparin). At 7 days, cultured explants were analysed for changes in intimal and medial thickness and by immuno-histochemistry. Comparisons were made with explants at initial isolation and with similar, cultured explants of normal LSV.

Results:

In normal LSV, by day 7, SMC-derived neo-intimal hyperplasia developed ( p<0.01) with an increase in intimal thickness ( p<0.02) and a decrease in medial thickness ( p<0.001). Heparin at 10 and 100 IU/ml further enhanced this neo-intima formation ( p<0.001). In contrast, at 1000 IU/ml, heparin inhibited neo-intima formation. In varicose explants, the pattern of intimal and medial changes was different. At isolation, varicose LSVs had substantially thicker intimal layers ( p<0.001). When cultured alone, a thicker media developed ( p<0.001) but there was little change in intimal thickness. Heparin at all concentrations had no effect on the thicker medial development seen in controls but did, however, reduce intimal thickness ( p<0.005).

Conclusions:

The response to heparin in explants of varicose LSV is different from that of normal LSV, which is biphasic and complex.

A NiTi alloy-based cuff for external banding valvuloplasty: a six-week follow-up study in pigs

OBJECTIVE

The study aimed to test a Nitinol(®)-based vein cuff model for external banding valvuloplasty.

METHOD

In 12 adult minipigs, the vena jugularis externa was covered for 42 days by a cuff with an inner diameter adapted to the outer vein diameter in supine position. By changing from supine into prone position hypostatically vein dilation was induced to simulate varicose vein dilation. Cuff position and the inner diameter of the vein lumen under the cuff were examined by computer tomography scanning. Also, histological analysis of the vein wall within the cuff was performed.

RESULTS

The preset tubular shape of the cuff and the cuff position did not change in both prone and supine position, but due to fibrosis the luminal vein diameter within the cuff was decreased (P < 0.01) already after 21 days.

CONCLUSION

A foreign body response resulted in a fibrous capsule covering the cuff which might limit cuff functionality.

Pathogenic mechanisms in varicose vein disease: the role of hypoxia and inflammation

AIMS

Although the aetiology of varicose veins remains unknown, recent studies have focused on endothelial cell integrity and function. Among the regulatory factors of vessel tone, synthesises, pro- and anti-inflammatory, adhesion molecules and the transcription factor hypoxia inducible factor-1 alpha (HIF-1alpha), which are responsible for recruiting leukocytes, are very important.

METHODS

Investigation in this study focused on the expression of ICAM-1, E-selectin and HIF-1alpha on endothelial cells using immunostaining and RT-PCR in varicose vein specimens compared with controls.

RESULTS

Findings of this study showed alterations of the intima, such as focal intimal discontinuity and denudation of endothelium in varicose veins. Based on data derived from immunostaining and RT-PCR, no major differences were identified between ICAM-1 and E-selectin expression in varicose vein specimens compared with controls. In contrast, immunostaining results identified HIF-1alpha expression in five (5/20) varicose vein specimens, whereas no control saphenous vein specimens expressed HIF-1alpha.

CONCLUSIONS

These findings could explain other evidence of hypoxia in varicose veins. Finally, results already obtained in this investigation suggest that the process of pathogenesis of varicose veins is not restricted to the role of adhesion molecules.

Intimal changes in varicose veins: an ultrastructural study

In order to study the structural changes in the intimal layer of varicose veins, we prospectively collected a total of 23 vein specimens from both the normal proximal thigh long saphenous (LSV) in 3 young trauma patients and from the unstripped proximal LSV near the sapheno-femoral junction and the distal calf blowouts in 10 primary varicose veins patients. Paraffin sections stained with hematoxylin and eosin were examined under the light microscope while ultra-thin sections were examined under the transmission electron microscope (TEM). Compared with the normal control LSV, varicose vein sections showed increase in the diameter of the lumen, hypertrophy of the wall and elongation and invagination of the intima. Along these invaginations, endothelial cells were compressed, elongated and thinned out. The cells also showed progressive degeneration and were finally lost into the lumen, leaving only the basal lamina to form the luminal surface. This invited blood components like platelets and red blood cells to stick to the bare intima and to penetrate through the wall. This may form the basis of the clinical condition of superficial thrombophlebitis, which sometimes complicates cases of varicose veins. In conclusion, varicose veins showed increased diameter of the lumen and hypertrophy, elongation and invagination of the intima. There was marked degeneration of the endothelial cells and desquamation of the endothelial layer.

Varicose veins: loss of release of vascular endothelial growth factor and reduced plasma nitric oxide

OBJECTIVES

To examine the release of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in primary varicose veins (VVs) and normal vein controls following experimentally-induced venous stasis.

DESIGN, MATERIALS AND METHODS

Patients with primary VVs (n=21) and control subjects (n=11) were rested supine for 15 min. Blood was collected from both an arm and foot vein. A below-knee cuff was applied and inflated to 90-95 mmHg for 10 min (to prompt venous stasis). Further blood samples were collected from the foot vein. Levels of plasma VEGF and NO were analysed.

RESULTS

In control subjects, application of the cuff increased levels of plasma VEGF in the foot (p<0.025). In contrast, in patients with VVs, there was little or no change in these levels of plasma VEGF. Cuff application had little effect on levels of plasma NO in either controls, or those with VVs. When compared to controls however, the levels of plasma NO in all samples with VVs (arm, or foot before, or after, cuff application) were reduced (all, p<0.05).

CONCLUSIONS

Loss of VEGF release with experimentally-induced venous stasis, and reduced levels of plasma NO may suggest a mechanism important in the development of primary VVs.

Smooth muscle changes in varicose veins: an ultrastructural study

In order to understand the pathology of varicose veins, we prospectively collected a total of 23 vein specimens both from the normal proximal thigh long saphenous vein (LSV) in 3 young trauma patients and from the unstripped proximal LSV near the sapheno-femoral junction and the distal calf blowouts in 10 primary varicose veins patients. Ultra-thin sections were examined under the transmission electron microscope (TEM). Compared with the normal control LSV, varicose vein sections showed increase in the diameter of the lumen, hypertrophy of the wall and elongation and invagination of the intima. Smooth muscle cells (SMCS) lost their normal fusiform shape and were widely separated by increased amounts of extra-cellular collagen fibers. The cells underwent marked degeneration, vacuolization and disintegration into fiber-like material and small separated fragments. SMCs were seen in the subintimal tissue and some of them were lost into tile lumen. SMCs also showed marked phagocytic activity, engulfing not only collagen and elastic fibers, but also other smooth muscle cells. Although these changes were more marked and advanced in the distal calf blowouts, they were also present in the proximal, clinically non-dilated LSV. In conclusion, SMCs of varicose veins show severe degeneration in both the distal calf blowouts and the proximal, clinically non-varicose LSV. It appears that they both form and phagocytose collagen and elastic fibers and play a major role in the pathogenesis of varicose veins.

Leukocyte activation in patients with venous insufficiency

PURPOSE

Cell activation may play an important role in the production of venous insufficiency, just as leukocytes participate in the cause of venous ulcer. If activated, monocytes observed on venous endothelium can migrate into the venous wall and produce toxic metabolites and free oxygen radicals that may participate in valve destruction and venous wall weakening. At present, it remains uncertain to what degree leukocytes are actually activated in patients. This study was designed to explore the level of activation and to examine whether patient plasma contains an activator that leads to leukocyte activation of unstimulated naive leukocytes from volunteers without venous insufficiency disease.

METHODS

Twenty-one patients (4 men, 17 women), who ranged in age from 34 to 69 years (mean age, 53.2 years), with chronic venous disease were compared with 16 healthy control volunteers (4 men, 12 women), who ranged in age from 18 to 65 years (mean age, 48.4 years). All the patients underwent evaluation with Doppler ultrasound scanning and were classified with the CEAP score.1 Nearly all the patients who smoked or were hypertensive were excluded. The blood types (ABO and Rh) of the controls were matched to the study group. Isolates of patient whole blood, plasma, or leukocytes were incubated with isolates of control whole blood, plasma, or leukocytes to separate actual activation from spontaneously observed activation. The granulocyte activation was measured with nitroblue tetrazolium (NBT) reduction and quantitation of granulocyte pseudopod formation. Hydrogen peroxide production in patient plasma was measured with a recently developed electrode method.

RESULTS

Leukocytes from healthy blood and patient plasma had significantly higher NBT-positive granulocyte counts than either patient blood, healthy blood, or patient blood incubated in healthy plasma. In a comparison of patient groups across the CEAP classes, the NBT-positive granulocyte counts were significantly greater in classes 4, 5, and 6 than in classes 2 and 3 (P <.001). Pseudopod formation was significantly greater in mixtures of granulocytes in healthy blood and patient plasma than in all other groups. There was no difference in the level of pseudopod formation in control leukocytes incubated with patient plasma in patients across the CEAP spectrum. The patient plasma produced significantly higher hydrogen peroxide values than did the controls.

CONCLUSION

These results suggest that patient plasma may contain an activating factor for granulocytes. The finding that activated neutrophils were fewer in number in patient whole blood than in healthy blood incubated in patient plasma could suggest that activated neutrophils in patients with chronic venous insufficiency might be trapped in the peripheral circulation. It is unknown what factors in the plasma might induce activation of naive neutrophils, but such activators could possibly be important in the pathogenesis of primary venous dysfunction and the development of chronic venous insufficiency.

Smooth muscle differentiation in human vein wall at valvular level: comparison with nonvalvular wall and correlation with venous function

The aim of this study was to evaluate local differences in smooth muscle differentiation in venous valves of patients suffering from chronic venous insufficiency, in relation to functional hemodynamic parameters measured by echo Doppler. These functional parameters did not correlate with smooth muscle differentiation at the valvular site. These results failed to support an initiating role of valvular structure in the development of chronic venous insufficiency. However, this work stresses differences in cellular differentiation of valve wall and nonvalvular smooth muscle cells in culture, and we found histologic differences in the structure of endovein and media (connective tissue relative content) between valvular and nonvalvular venous wall. The presence of smooth muscle cells in the valve cusp was demonstrated by smooth muscle alpha-actin-specific labeling and was observed to be restricted to one side of the valve cusp.

Assessment of wall structure and composition of varicose veins with reference to collagen, elastin and smooth muscle content

OBJECTIVES

To compare collagen, elastin and smooth muscle contents of varicose and control long saphenous veins.

DESIGN

Collagen, elastin and muscle were estimated stereologically using random sampling and histological staining.

MATERIALS

Varicose vein samples were collected from nine patients (mean age 52 years, range 34-64 years) undergoing vein stripping, sample sites being saphenofemoral junction and knee. Control samples were taken from five patients (mean age 58 years, range 38-76 years) presenting for femoral-popliteal bypass at equivalent levels.

METHODS

Veins were fixed, sectioned transversely, and stained with Picric Acid Sirius Red. Analysis of samples was performed using point and intersection counting on vertically projected images.

RESULTS

Using two way analysis of variance tests, varicose saphenous veins had significantly larger wall areas (p < 0.01) and higher amounts of collagen (p < 0.01). Collagen content and wall area were significantly larger proximally compared to distally in both control and varicose veins (p < 0.05) with a higher content of smooth muscle and elastin in varicose veins proximally compared to distally (p < 0.05). There was no difference in wall thickness or elastin content between the two groups.

CONCLUSIONS

This suggests that varicose veins are a dynamic response to venous hypertension and are not thin walled structures as previously thought.