Peripheral venous tone was measured in 124 patients with essential hypertension and in 20 healthy persons by digital electroplethysmography according to B. E. Votchal. In patients with hypertension stage II, the venous tone significantly decreased with increasing arterial tone; in patients in stage I this tendency was statistically not significant. In orthostasis the increase in venous tone was much lesser than that in arterial tone. The close positive correlation between venous capacity and the degree of decrease in systolic and pulse pressure make it possible to assess the systemic venous pressure on the basis of findings obtained from occlusion plethysmographic measurements. In patients with hypertensive disease in stage IIA, treated with reserpine, the arterial tone and pressure decreased, whereas the venous tone significantly increased (normalized).

• MeSH
• arterie patofyziologie   MeSH
• dospělí MeSH
• hladké svalstvo patofyziologie   MeSH
• hypertenze patofyziologie   MeSH
• krevní objem MeSH
• lidé středního věku MeSH
• lidé MeSH
• pletyzmografie impedanční MeSH
• postura těla MeSH
• prsty ruky krevní zásobení   MeSH
• svalový tonus MeSH
• venózní tlak MeSH
• vény patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

AIM: To evaluate the importance of surgical bypass between the terminal part of functional arteriovenous shunt (av) for hemodialysis on upper extremity and inner jugular vein in axillosubclavian venous segment obstruction associated with central venous hypertension. METHOD: Retrospective assessment of surgical bypass between central segments of av fistula and ipsilateral/contralateral inner jugular vein using ePTFE graft in 17 patients over a 20 year period (1987-2006). RESULTS: The surgical procedure was not associated with intra- or post-operative complications. Primary cumulative bypass and av fistula function persisted for 26 months on average. CONCLUSION: An accurate bypass to salvage the functional dialysis access associated with central venous hypertension requires careful decision based on clinical and radiological examination. The bypass procedure is beneficial where endovascular treatment is not indicated. Clinical and radiological bypass monitoring is crucial.

• MeSH
• arteriovenózní zkrat škodlivé účinky   MeSH
• centrální žilní tlak * MeSH
• dialýza ledvin * MeSH
• katetrizace centrálních vén škodlivé účinky   MeSH
• lidé středního věku MeSH
• lidé MeSH
• paže krevní zásobení   MeSH
• stenóza MeSH
• vena axillaris patologie   MeSH
• vena subclavia patologie   MeSH
• výkony cévní chirurgie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The authors emphasize the need for the investigation of the central venous system prior to the insertion of an avfistula, this they consider to be of utmost importance in patients with anamnesis of central vessel access. After the av-fistula is inserted, an unrecognized obstacle (stenosis or thrombosis) may result in the occurrence of venous hypertension and hypofunction, this may lead to av-fistula malfunction.

• MeSH
• arteriovenózní zkrat škodlivé účinky   MeSH
• dialýza ledvin * MeSH
• lidé MeSH
• okluze cévního štěpu komplikace   diagnóza   MeSH
• venózní tlak * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• Klíčová slova
• RESERPINE/toxicology *, THROMBOPHLEBITIS/diagnosis *,
• MeSH
• hypertenze * MeSH
• lidé MeSH
• reserpin toxicita   MeSH
• tromboflebitida diagnóza   MeSH
• žilní trombóza * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• reserpin MeSH

Vasomotor disregulation, preponderantly expressed by a pathological increase of central venous pressure (CVP) in calves with total artificial heart (TAH), starts to be evident from about the 50th day of pumping. The main cause of this state is an imbalance in cardiac receptor areas. Ventricular vasodepressor mechanisms are eliminated with the ventricular tissue, which is replaced by the artificial blood pump. In the stumps of both atria, which remain in situ, all neural elements disappear immediately after TAH implantation, but within two months they are fully regenerated. Regenerated atrial receptors are the starting points of afferent neural stimuli, which in the vasomotor center of the brainstem, increase the activity of the vasoconstricting functional component. A general tendency to vasoconstriction, now not well counterbalanced, increases, and the progressive venous hypertension causes loss of liver function and morphology. Two therapeutic approaches were tried: afferent therapy by atrial electrical stimulation, and efferent therapy by the administration of antihypertensives. Both kinds of this therapy were sufficiently effective in reducing CVP, protecting the liver, and prolonging average survival.

• MeSH
• antihypertenziva terapeutické užití   MeSH
• centrální žilní tlak * účinky léků   MeSH
• clonidin terapeutické užití   MeSH
• hypertenze terapie   MeSH
• jaterní testy MeSH
• kaptopril terapeutické užití   MeSH
• kardiostimulace umělá * MeSH
• methyldopa terapeutické užití   MeSH
• nifedipin terapeutické užití   MeSH
• pooperační komplikace terapie   MeSH
• prazosin terapeutické užití   MeSH
• skot MeSH
• umělé srdce * MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• antihypertenziva MeSH
• clonidin MeSH
• kaptopril MeSH
• methyldopa MeSH
• nifedipin MeSH
• prazosin MeSH

The function of an arteriovenous (av) fistula for haemodialysis may be complicated by manifestation of peripheral venous hypertension, which results from the arterial blood flow through the venous system into the periphery of the upper extremity. Its development is most typically caused by a proximal forearm av-fistula, as, in addition to the desirable arterialisation of the subcutaneous venous system of the arm, arterialisation of the venous system of the forearm and the hand may occur and possibly promote the development of venous hypertension, which may in the extreme result in gangrene of the fingers. Awareness of these problems as well as of the necessity of their surgical solution is essential for doctors dealing with haemodialysis.

• MeSH
• arteriovenózní zkrat škodlivé účinky   MeSH
• dialýza ledvin * MeSH
• lidé MeSH
• předloktí krevní zásobení   MeSH
• ruka krevní zásobení   MeSH
• venózní tlak * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Stenosis or thrombosis of the central venous tract (axillaris or subclavian vein) may be after creation of arteriovenous fistula for hemodialysis the cause of manifestation of venous hypertension. The authors evaluate positive bypass to internal jugular vein in the therapy of this complication.

• MeSH
• arteriovenózní zkrat škodlivé účinky   MeSH
• dialýza ledvin * MeSH
• dospělí MeSH
• hypertenze etiologie   terapie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• retrospektivní studie MeSH
• vena axillaris chirurgie   MeSH
• vena subclavia chirurgie   MeSH
• venae jugulares chirurgie   MeSH
• žilní trombóza etiologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH

Renal venous and peripheral plasma renin activities were determined in 29 operated patients with renovascular hypertension and in 10 patients with essential hypertension. The majority of patients with renovascular hypertension exhibited elevated peripheral plasma renin activity, but the most striking increase of renin activity was demonstrated in the venous effluent of the involved kidney. Using data obtained in patients with essential hypertension, the ratio of renal vein renin activity not exceeding 1.4 was assumed normal. In patients with renovascular hypertension, the values above 1.4 were accepted as lateralizing ratios. In 78.6 % of patients with unilateral renal artery stenosis and a lateralizing renal vein renin ratio, normotension or improvement of blood pressure control were obtained post-operatively. The discussion emphasis the importances of renal vein renin estimations with the calculation of renal vein ratio for determining the functional significance of renal artery stenosis and for predicting the surgical outcome

• MeSH
• dospělí MeSH
• hypertenze krev   patofyziologie   MeSH
• kreatinin krev   MeSH
• krevní tlak MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• obstrukce renální arterie krev   patofyziologie   chirurgie   MeSH
• pooperační komplikace patofyziologie   MeSH
• renální hypertenze krev   patofyziologie   chirurgie   MeSH
• renin krev   MeSH
• venae renales patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kreatinin MeSH
• renin MeSH

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.

• MeSH
• bércové vředy etiologie   patologie   patofyziologie   MeSH
• bérec krevní zásobení   MeSH
• chronická nemoc MeSH
• lidé MeSH
• regionální krevní průtok MeSH
• stupeň závažnosti nemoci MeSH
• varixy komplikace   patologie   patofyziologie   MeSH
• vena saphena patofyziologie   MeSH
• venózní tlak * MeSH
• vény patologie   patofyziologie   MeSH
• žilní insuficience komplikace   patologie   patofyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Calf muscle pump is the motive force enhancing return of venous blood from the lower extremity to the heart. It causes displacement of venous blood in both vertical and horizontal directions, generates ambulatory pressure gradient between thigh and lower leg veins, and bidirectional streaming within calf perforators. Ambulatory pressure gradient triggers venous reflux in incompetent veins, which induces ambulatory venous hypertension in the lower leg and foot. Bidirectional flow in calf perforators enables quick pressure equalization between deep and superficial veins of the lower leg; the outward (into the superficial veins) oriented component of the bidirectional flow taking place during calf muscle contraction is no pathological reflux but a physiological centripetal flow streaming via great saphenous vein into the femoral vein. Calf perforators are communicating channels between both systems making them conjoined vessels; they are not involved in the generation of pathological hemodynamic situations, nor do they cause ambulatory venous hypertension. The real cause why recurrences develop has not as yet been cleared. Pressure gradient arising during calf pump activity between the femoral vein and the saphenous remnant after abolition of saphenous reflux triggers biophysical and biochemical events, which might induce recurrence. Thus, abolition of saphenous reflux removes the hemodynamic disturbance, but at the same time it generates precondition for reflux recurrence and for the comeback of the previous pathological situation; this chain of events has been called hemodynamic paradox.

• Klíčová slova
• calf perforators, hemodynamic paradox, venous hemodynamics, venous hypertension,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH