Nejvíce citovaný článek - PubMed ID 23997567
The hemodynamic paradox as a phenomenon triggering recurrent reflux in varicose vein disease
Saphenous reflux interferes with the physiological decrease in pressure and induces ambulatory venous hypertension. Elimination of reflux is achieved by flush ligation at the incompetent saphenofemoral junction and stripping of the great saphenous vein, which is the basis of the conventional surgical therapy. Endovenous ablative methods substitute stripping by thermal of chemical destruction of the saphenous trunk; they usually refrain from saphenofemoral junction ligation. Short-term and medium-term results up to 5 years, achieved after endovenous ablation without high ligation, are comparable with those after conventional surgery, which questioned the necessity to ligate the incompetent saphenofemoral junction. Nevertheless, clinical symptoms caused by recurrent reflux occur as a rule not earlier than 8 to 10 years after efficient abolition of reflux. Consequently, randomized studies with long-term follow-ups exceeding 10 years are necessary for trustworthy assessment whether it is justified to abstain from saphenofemoral junction ligation.
- Klíčová slova
- endovascular procedure, endovenous ablation, greater saphenous vein, lower extremity, radiofrequency ablation, varicose veins, vein reflux,
- 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