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C Recek

Publications and source records attributed to C Recek.

At least 19 recordsLinked to original sources
PubMed2006

Impact of the calf perforators on the venous hemodynamics in primary varicose veins.

The hemodynamic significance of the calf perforating veins continues to be the point of controversy. The conception that incompetent perforating veins cause hemodynamic disturbance and are responsible for the formation of leg ulceration has still many adherents prefering perforator surgery, whereas others reject any causal relation between large, incompetent perforators and severe forms of chronic venous insufficiency. In this study well documented facts concerning the impact of the calf perforators on the venous hemodynamics are reviewed. There is a bidirectional flow within calf perforators in healthy subjects enabling a quick equilibration of pressure changes produced during calf muscle contractions and relaxations, so that recordings of the mean pressure display identical values in superficial and deep veins of the lower leg, a feature typical of conjoined vessels. In cases with saphenous reflux, the bidirectional flow within calf perforators has a distinct inward vector directed to the deep veins; this inward component is the more pronounced, the larger the saphenous reflux is. Incompetent calf perforators do not cause ambulatory venous hypertension, exactly the opposite happens: the high hydrostatic pressure found in the quiet standing position drops significantly during ambulation, as soon as the saphenous reflux is interrupted. In primary varicose veins calf perforators can not become the source of reflux because they are situated at the lower pole of the ambulatory pressure gradient, which occurs between thigh and lower leg veins during ambulation. The size of the calf perforators is determined by the amount of saphenous reflux. When the saphenous reflux is abolished (e.g. by high ligation), the enlarged calf perforators diminish.

Chronic Disease↗
PubMed2003

[Evaluation of the hemodynamic significance of femoral vein insufficiency].

Deep vein incompetence is generally regarded as the main cause of severe chronic venous insufficiency, without specifying which deep vein segments are really meant. Opinions concerning hemodynamic significance of femoral vein incompetence differ considerably. Femoral vein incompetence can be part of a postthrombotic syndrome, it can occur as a primary incompetence described by Kistner or as a secondary incompetence due to vein dilatation. Therapeutic possibilities and outcome of valvuloplasty and valve transplantation described in the literature are presented. The results of valve transplantation into the popliteal vein in postthrombotic patients were disappointing. In primary varicose veins the saphenous incompetence is often accompanied by femoral vein reflux which mostly disappears after removal of incompetent saphenous vein; the possible mechanism causing this phenomenon is discussed. In cases with combined saphenous and femoral vein reflux the most important factor causing venous derangement is the saphenous reflux, not the femoral vein incompetence; therefore, the first therapeutic step in such cases must be the abolition of saphenous reflux. The question whether femoral vein incompetence deteriorates the natural course of primary varicose veins can't so far be answered conclusively, but the first reports concerning this issue show that it could be answered yes.

Femoral Vein↗
PubMed2003

[Hemodynamic basis for the development of varicose ulcers and their therapy].

The prevalence of leg ulcers is about 1%, approximately 75% of them are of venous origin. The precondition for the development of venous ulcers is ambulatory venous hypertension. It is assumed than a linear correlation exists between the severity of ambulatory venous hypertension and the incidence of venous ulcers. Venous ulcers caused by superficial vein reflux are called varicose ulcers and are more frequent than postthrombotic ones. Crossectomy removes the hemodynamic disorder responsible for the development of varicose ulcers and creates conditions for a quick and mostly definitive ulcer healing. In cases with simultaneous reflux in the saphenous and femoral veins the saphenous reflux is responsible for the severity of venous disorder, whereas femoral reflux is hemodynamically unimportant. Selective abolition of saphenous reflux restores normal hemodynamic conditions in such cases. Compressive therapy continues to be the most frequently used therapeutic procedure in the treatment of venous ulcers; it must be considered as a symptomatic measure, because it is not able to substantially affect the underlying venous disorder in spite of the fact that the correctly lying bandage positively influences venous hemodynamics. The diagnostic procedure in patients with leg ulcers should screen out cases with varicose ulcers; abolition of superficial vein reflux can deliver these patients from their annoying disease.

Hemodynamics↗
PubMed2003

[Does saphenous vein saving surgery have a role in the therapy of primary varices?].

Venous grafts retrieved from long saphenous veins are the best conduits for vascular and coronary reconstructions. The demand for such grafts rise continuously with the development of vascular and coronary surgery. Surgeons were soon confronted with the problem whether the saphenous trunk in patients with varicose veins may be used for grafting or not. Saphenous vein saving surgery means intentional renouncement of removing the saphenous trunk during varicose vein surgery and saving it for a possible graft in the future. Opinions whether such procedures are substantiated differ widely and concern both the suitability of such grafts and the fact that lowering the radicality of varicose vein surgery increases the probability of varicose vein recurrence. The saphenous trunk in primary varicose veins is not diffusely degenerated, it usually shows only a few local bulges and is basically compatible for the use as a vascular or coronary artery conduit; it does not dilate aneurysmatically when transplanted into the arterial circulation. Crossectomy disconnects saphenofemoral junction, the most frequent source of reflux, abolishes even the most serious venous derangement and restores normal venous hemodynamics; stripping brings about no further immediate amelioration. Recurrence of varicose veins is more frequent when crossectomy alone is performed in comparison with crossectomy and stripping, but nor crossectomy combined with stripping is able to reliably prevent recurrence, because the distinct tendency to recur is a characteristic feature of varicose disease. Saphenous vein saving surgery can be efficiently supplemented by sclerotherapy during follow-up. The excellent hemodynamic improvement achieved immediately after crossectomy can be preserved for many years during follow-up by repeated applications of sclerotherapeutic agents. In this way necessary conditions for a rapid and mostly a definitive healing of varicose ulcers can be established. In addition, preservation of a possible graft for arterial reconstructions is relevant in elderly patients.

Humans↗
PubMed2002

[Principles of surgical treatment of varicose veins with regard to new findings on venous hemodynamics].

Pressure changes occurring during the activity of the calf muscle venous pump are the driving force of venous hemodynamics in the lower extremity. An ambulatory pressure gradient arises between the veins of the thigh and the lower leg as a consequence of pumping up the blood from the deep veins of the lower leg, where the venous pressure decreases, into the popliteal and femoral vein, where no pressure decrease occurs. Therefore, venous reflux can only take place in an incompetent vein connecting the femoral, profunda femoris, popliteal or iliac vein with one of the deep veins of the lower leg. Calf perforators represent the so called re-entry points and can't become the source of reflux. Venous reflex disturbs venous hemodynamics to a various degree dependent on the magnitude of reflux volume. When strong enough, it can produce the graviest form of chronic venous insufficiency even if localised in superficial veins. The magnitude of reflux volume, not the localisation of reflux in deep or superficial veins is the most important hemodynamic factor causing venous disturbance. The goal of varicose vein surgery is to remove reflux and visible varicose veins with the aim to achieve the most favorable hemodynamic and cosmetic results. Crossectomy is a very important step, because it is able to repair even the most pronounced hemodynamic disorder and restore normal hemodynamic conditions. If stripping of the incompetent saphenous trunk on the thigh is not performed in addition to crossectomy, the saphenous trunk continues to be patent and incompetent after surgery in most patients and provokes recurrent reflux. But nor can crossectomy combined with stripping avert the risk of recurrence definitively, because varicose veins are a dynamic disease with distinct tendency to recurrence. Correctly performed operation can reduce the recurrence rate and postpone its occurrence. A hemodynamic factor--the ambulatory pressure gradient--triggers probably the process leading to recurrence. When varicose veins recur, the recurrent reflux volume remains significantly lower for many years of follow-up as compared with the situation before surgery. External banding of incompetent valve in the long saphenous vein and the CHIVA-method are less efficient in comparison with standard surgery (crossectomy plus stripping). Sclerotherapy is a useful supplement to surgery during follow-up, as it is able to improve significantly the hemodynamic situation. This improvement is only transitory, but sclerotherapy can be repeated and the improvement re-established, if necessary, during follow-up.

Hemodynamics↗
PubMed2000

Ambulatory pressure gradient in the veins of the lower extremity.

BACKGROUND: Neovascularization is an important cause of venous reflux recurrence after high ligation of the long saphenous vein. The pathogenesis of this phenomenon is so far obscure. It is possible that a hemodynamic factor--a pressure gradient between the femoral vein and the residual long saphenous vein--could be the trigger initiating the process of neovascularization. PATIENTS AND METHODS: Venous pressure measurements on eight patients with primary varicose veins were performed in the erect position in the insufficient long saphenous vein on the thigh. Mean pressures in the quiet standing position and ambulatory pressures were considered. By interrupting the saphenous reflux either distally or proximally to the point of measurement the pressure conditions either in the femoral or in the crural veins were simulated. RESULTS: With the tourniquet placed distally to the point of measurement, the venous pressure in the upper interrupted segment of the long saphenous vein (equivalent to the pressure in the femoral vein) remained uninfluenced during ambulation. In contrast, by interrupting the reflux proximally to the point of measurement, a marked decrease of the ambulatory pressure in the lower part of the long saphenous vein (equivalent to the pressure in the crural veins) was noted. CONCLUSIONS: A pressure difference occurs between the veins of the thigh and the lower leg during the activation of the muscle venous pump. This fact may explain the tendency of recurrencies of varicose veins after high ligation of the long saphenous vein as well as the initiation of reflux.

Adult↗
PubMed2000

Author's reply

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Journal Article↗
PubMed1996

[Insufficiency of crural perforators: myths, dogma and reality].

The author evaluates critically ideas on the importance of insufficient crural perforators in the pathogenesis of primary varicosities, incl. states with chronic venous insufficiency. Based on published facts assessed by phlebodynamometry, assessment of the blood flow, duplex sonography and plethysmography, the author provides evidence that impaired venous circulation is due to reflux in the insufficient saphenous vein. Conversely insufficient crural perforators do not cause venous disorders but are due to reflux in the insufficient saphenous vein.

Humans↗
PubMed1982

Decompression of the left ventricle in the recovery period during myocardial revascularization.

Effective left heart decompression is essential for the reduction of myocardial oxygen consumption during recovery from an induced ischemic insult. During the early postischemic recovery phase of patients undergoing aorto-coronary bypass surgery, left ventricular, left atrial and aortic pressures were measured in non-vented hearts and in 2 types of left ventricular decompression. The following findings were made: Total cardiopulmonary bypass with effective decompression of the left ventricle decreases peak systolic left ventricular pressure, thereby reducing oxygen consumption of the myocardium. In this way adequate conditions are provided for recovery of the myocardium after unclamping of the aorta. The best method for decompression appears to be the placing of a large-lumen cannula in the left ventricle and allowing the blood to pour freely from the vent. The zero or near zero left ventricular filling pressure achieved with total cardiopulmonary bypass but without ventricular decompression does not prevent the chamber from producing isometric pressure work with peak systolic pressure reaching 80 to 90 torr. The hazard of air embolism may be reduced by precautionary measures. Left atrial monitoring permits recognition of pressure decreases to negative values. Active suction of the blood from the left ventricle is dangerous and should be avoided.

Blood Pressure↗