Chronic Venous Incompetence Research Articles

VenasealTM Cyanoacrylate Glue Rejection Following Endovenous Ablation - Another New Complication

The VenaSealTM closure system (Medtronic, Minnesota, USA) is a medical tissue adhesive containing n-butyl-2 cyanoacrylate, injected endovenously to treat varicose veins and superficial chronic venous incompetence (CVI), resulting here in a new treatment –related complication.

The role of perforating vein dissection in the treatment concept of venous ulcers--myths and evidence

Crural ulcers represent the most serious form of chronic venous incompetence (CVI). According to duplex studies superficial venous incompetence predominate in this stage of the disease, but combined refluxes of superficial and deep veins are also common. Despite a positive correlation between the number of incompetent perforators and the stage of CVI isolated incompetence of perforating veins in venous ulcers are rarely found. Additionally, only a minority of incompetent perforators depict larger reflux volumes. Therefore, doubts about a causal role of perforators incompetence in ulcer genesis are justified. According to phlebodynamometric studies the risk of crural ulcer development increases with the degree of hemodynamic compromise. Ulcer healing can only be achieved after complete normalization of ambulatory venous hypertension. In case of superficial refluxes and concomitant incompetence of perforating veins exclusion of the superficial component is sufficient to achieve this goal. Incompetent perforators normalize their function consecutively. In contrast, venous hypertension persists after exclusion of superficial refluxes in case of incompetent perforators and irreversible damage of the deep venous system. Surgical therapy studies exactly reflect the results of these hemodynamic examinations. Therefore, the role of endoscopic subfascial perforator dissection (ESPD) in the treatment of venous ulcers remains unclear. Future therapy studies should take into account that the definite role of ESPD in ulcer healing can only be examined without additional treatment of refluxes in the saphena system. Additionally, all study patients should be classified according to the CEAP nomenclature and Hach's classification of chronic compartment syndrome. Methodological differences in technique and extent of ESPD have also to be taken into account.

The cutaneous uptake of atmospheric oxygen contributes significantly to the oxygen supply of human dermis and epidermis.

It has been known since 1851 that atmospheric oxygen is taken up by the human epidermis. The contribution to total respiration is negligible. Until now the significance for the local oxygen supply of the skin has remained unknown. With a newly developed sensor, the oxygen fluxoptode, it has become possible to make local measurements of the transcutaneous oxygen flux (tcJ(O2)). In this study the sensor was calibrated so that absolute values of tcJ(O2) could be reported. At rest, tcJ(O2) was determined on normal, humidified skin on the volar forearm of 20 volunteers of different age groups. In order to evaluate the contribution of the blood flow to the oxygen supply of the skin, tcJ(O2) was recorded at the end of a 5 min suprasystolic occlusion of the forearm. At normal skin surface partial oxygen pressure (163 +/- 9 Torr), tcJ(O2) was 0.53 +/- 0.27 ml O2 min(-1) x m(-2). A 5 min interruption of blood flow resulted in an increase of 9.5 +/- 6.3 % in tcJ(O2). The value of tcJ(O2) was unaffected by the age of the subject. Published data on the oxygen diffusion properties of skin and simulations of intracutaneous profiles of oxygen partial pressure indicated that under these conditions, the upper skin layers to a depth of of 0.25-0.40 mm are almost exclusively supplied by external oxygen, whereas the oxygen transport of the blood has a minor influence. As a consequence, a malfunction in capillary oxygen transport cannot be the initiator of the development of superficial skin defects such as those observed in chronic venous incompetence and peripheral arterial occlusive disease.

Local Oxygen Content in the Skin Is Increased in Chronic Venous Incompetence

In skin lesions of chronic venous incompetence (CVI) transcutaneous oxygen pressure (tcpO2) at the ankle is often reduced. However, in some CVI patients the tcpO2 during suprasystolic occlusion remains significantly higher than in healthy subjects. The aim of the present study was to investigate which kind of CVI patients develop this phenomenon and whether the higher tcpO2 during occlusion is caused by a smaller oxygen consumption of the skin or by an increased local oxygen content. The oxygen consumption of the skin was measured by the pO2 decrease (ΔtcpO2/Δt) after stopping the arterial oxygen supply when the hemoglobin was saturated by oxygen inhalation, i.e., at tcpO2 values above 120–130 mmHg. By multiplying the tcpO2 with the mean oxygen solubility coefficient of the skin the content of physically dissolved oxygen is obtained. The decrease of tcpO2 in the 55- to 45-mmHg range indicates the consumption of oxygen physically dissolved and chemically bound to hemoglobin. It gave a parameter for estimating the local hemoglobin content of the skin. These values and the minimal tcpO2 after a 5-min arterial occlusion were measured in 14 healthy subjects, in 13 patients with varicose veins, but no skin lesions, in 10 patients with CVI lesions like white atrophy and lipodermatosclerosis and in 16 CVI patients with open venous ulcers. During suprasystolic occlusion tcpO2 at the ankle remained significantly higher in CVI patients with skin lesions than in the healthy control subjects (25.6 ± 18.9 versus 8.0 ± 7.0 mmHg). The steepness of the tcpO2 decrease caused by cutaneous oxygen consumption in healthy subjects was not significantly different from the CVI patients. In contrast, the decrease of tcpO2 at the ankle between 55 and 45 mmHg was 1.9 ± 2.0 mmHg/s in the control group and 0.7 ± 0.5 mmHg/s in the group with open venous ulcers. These results indicate a higher hemoglobin content in the skin of the CVI patients than in healthy subjects. Obviously, the hemoglobin bound oxygen content in the skin of CVI patients is increased. Thus, a lack of oxygen is unlikely to be the primary reason for the development of skin lesions in CVI.

Physical therapy of the ankle joint in patients with chronic venous incompetence and arthrogenic congestive syndrome.

Physical therapy of the ankle joint in patients with chronic venous incompetence and arthrogenic congestive syndrome.

Vascular sports in ambulatory therapy of venous circulatory disorders of the legs. Diagnostic, therapeutic and prognostic aspects

In 33 patients with chronic venous incompetence (CVI) caused by primary varicoses or postthrombotic syndrome stage I-III (according to Widmer) the therapeutic benefit of 6 months of medically supervised physical exercise training was documented. During the training penud there was an improvement in subjective complains such as pain and tendency for edema in the legs. Mobility in the upper ankle joint was improved asuss as venous drainage function. Clinical benefit was achieved in the reduction of ulcer size; 7 of the 10 ulcers completely healed. Medically supervised physical exercise training and optimized compression therapy are basic therapeutic approaches in conservative treatment in chronic venous insufficiency. Costs are covered by the patient's health insurance company in Germany, as long as the exercise training is medically supervised.

Dynamische In-vivo-Messungen des Anpreßdruckes von Kompressionsstrümpfen mit einer Mikro-Sonde - Dynamic In Vivo Measurements of the Pressure Exerted by the Compression Stocking Using a Microtip Probe

Conservative treatment of chronic venous incompetence is based on compression therapy, Carried out correctly, compression therapy improves the venous return from the legs, and also relieves cutaneous congestion. These positive haemodynamic effects are, however, only obtained when the pressure exerted by the compression stocking remains within the desired therapeutic range, not only at rest, i.e. while the patient is seated or reclining, but also during exertion while the patient is standing or walking, furthermore, the pressure exerted must decrease continuously from the tips of the toes to the trunk. Using the dynamic pressure monitoring system described here, the pressure exerted by the compression stocking can be measured continuously between the stocking and the skin at any desired site. The main component of the new microprocessor-based system is a microtip probe for measuring piezoresistance. The probe has an integrated signal filter and is connected to peripheral equipment which records the measured data. The technical design of the system makes it possible accurately to record dynamic measurements of the pressure exerted by compression materials in vivo. This measuring system represents a major step forward in understanding the dynamics of compression during locomotion in vivo, and towards optimizing modern compression therapy.

Capillary underperfusion in chronic venous insufficiency: a cause for leg ulceration?

Dermal capillaries in the goiter area of the lower leg were examined by video-microscopy before and after the administration of intravenous fluorescein in 13 patients with chronic venous insufficiency (CVI) who were at risk of developing leg ulceration, and in 13 normal controls. The influence of posture on capillary perfusion was determined by viewing the same area of skin with the leg in both the supine and dependent positions. Capillary density was lower in patients than in controls, irrespective of the position of the leg (P < 0.01). Fluorescence angiography studies in normal controls showed a reduction in capillary density with dependency (P < 0.01), but patients with CVI showed no significant change. Fluorescence angiography revealed a greater number of capillaries than seen during native capillaroscopy (P < 0.05). The decreased capillary density, and the loss of the postural vasoconstrictor reflex in patients with chronic venous incompetence may play a role in the pathogenesis of ulceration.

Endoscopic subfascial sectioning of incompetent perforating veins in treatment of primary varicosis.

Subfascial elimination of incompetent perforating veins is the most effective therapeutic principle in the treatment of trophic skin disorders associated with varicosis. A recently developed endoscopic technique allows accurate sectioning of perforating veins with direct observation of the veins and minor trauma. From November 1986 to July 1991 endoscopic sectioning of perforating veins was performed in 72 patients (103 legs). The most frequently transected perforating veins were Cockett's veins (n = 219), 24 cm perforating veins (n = 83), and Boyd's perforating veins (n = 82). Postoperative delayed wound healing was observed in 3 (2.9%) legs with pronounced trophic skin disorders in the lower extremities. Two patients complained of dysesthesia in the area of distribution of the sural nerve. Further complications recorded were extended subcutaneous hematoma in 6 (5.8%) legs and postoperative dysesthesia in the area of distribution of the saphenous nerve in 10 (9.7%) legs. At follow-up examination (mean 27 months postoperatively) clinical investigation and Doppler sonography showed newly formed incompetent perforating veins in only 2 lower legs. Radiography at follow-up revealed one incompetent Dodd's perforating vein in 1 leg, which was the starting point of pronounced recurrent varicosis in the lower leg. After an average follow-up of greater than 2 years, we recorded the occurrence of new varices in 9 lower legs. Staging of chronic venous incompetence showed an upward trend ranging from change to a more favorable stage to complete cure. Findings were unchanged in only 10% of the patients. There was no case of postoperative aggravation.

Transcutaneous oxygen tension and capillary morphologic characteristics and density in patients with chronic venous incompetence.

The transparent oxygen electrode, recently developed by Huch and his co-workers, permits monitoring of transcutaneous oxygen tension (tcPO2) at defined sites on the capillaroscopic image obtained by videomicroscopy. This combined system has been applied to study the nutritional skin capillaries of patients with chronic venous incompetence (CVI). The results of 44 studies in 17 patients with CVI demonstrated a direct correlation between tcPO2 and density and morphologic characteristics of the superficial capillaries. The mean tcPO2 was 47.7 +/- 14.4 mm Hg at the site of incompetent perforating veins of the ankle without major trophic changes. There was no statistically significant difference between the mean values obtained in patients and control subjects (56.8 +/- 9.9 mm Hg). Videomicroscopic examination revealed dilated and tortuous capillaries surrounded by halo formations. In areas of hyperpigmentation, induration, and hyperkeratosis, significantly decreased mean tcPO2 (22.5 +/- 7.0 mm Hg; p less than .001) corresponded to reduced capillary density (less than 10 capillaries/mm2). In avascular skin areas (scar tissue, white atrophy) tcPO2 was measured at 0 mm Hg. No capillaries, or a greatly reduced number, were visible at such sites, resulting in a distance between capillary and cathode tip of the oxygen sensor of greater than 100 micron. The combined system of tcPO2 measurement and simultaneous videomicroscopy gives new pathophysiologic information on the development of skin ulcers and may be useful for the objective comparison of different therapeutic modalities at the microcirculatory level.

Local microcirculation in chronic venous incompetence in leg ulcers

Local microcirculation in chronic venous incompetence in leg ulcers

Local Microcirculation in Chronic Venous Incompetence and Leg Ulcers

Most chronic leg ulcers (90 to 95%) are caused by incompetence of the deep venous system and/or the perforators of the lower leg. Superficial venous incompetence does not give rise to necrotic skin ulcers. The primary cause of venous leg ulcers is the marked increase in pressure that builds up in the deep veins of the lower leg during walking. This pressure is transformed to the skin vessels through the ankle perforators, out to the nutritional vascular bed of the skin. The intracapillary pressure increases tremendously and this causes the capillaries to dilate and become tortuous. The blood elements leak out through the capillary wall into the surrounding tissue and form a specific microedema, which gives rise to an effective nutritional block between the capillaries and the skin cells. This microedema is most probably the main cause of the development of venous leg ulcers.