What is venous insufficiency?

Venous outflow obstructionVenous insufficiency is a problem with the flow of blood from the veins of the legs back to the heart. It's also called chronic venous insufficiency or chronic venous stasis.

Veins have valves that keep the blood moving in one direction—toward the heart. In venous insufficiency, the valves in the veins of the leg don't work right. So fluid pools in the legs. This can lead to problems that include varicose veins.

What causes the problem?

Venous insufficiency is sometimes caused by deep vein thrombosis and high blood pressure inside leg veins.

You are more likely to have venous insufficiency if you:

  • Are older.
  • Are female.
  • Are overweight.
  • Don't get enough physical activity.
  • Smoke.
  • Have a family history of varicose veins.

What are the symptoms?

Symptoms affect the legs and may include:

  • Swelling, often in the ankles.
  • Varicose veins.
  • Itching.
  • Cramping.
  • Skin sores (ulcers).
  • Aching or a feeling of heaviness.
  • Changes in skin color.

How is it diagnosed?

Your doctor can diagnose venous insufficiency by examining your legs and by using a type of ultrasound test (duplex Doppler) to find out how well blood is flowing in your legs.

How is it treated?

You can wear compression stockings, which are tighter at the ankles than at the top of the legs, to reduce swelling and to relieve pain. They also can help venous skin ulcers heal. You can buy the stockings with or without a prescription.

You also can try to:

  • Get more exercise, especially walking. It can increase blood flow.
  • Avoid standing or sitting for a long time, which can make the fluid pool in your legs.
  • Keep your legs raised above your heart when you're lying down. This reduces swelling.

Deep Vein Thyron

SUMMARY

The importance of venous outflow obstruction is increasingly recognized as an important contributing factor in chronic venous disease. Obstruction of the iliofemoral venous outflow appears particularly important, and results in more severe symptoms than does lower segmental blockage. Selection of patients for treatment is hampered by the lack of accurate noninvasive or invasive tests for evaluation of obstruction. In fact, it is not known precisely what degree of venous stenosis should be considered hemodynamically critical. It is presently impossible to detect potentially hemodynamically important borderline obstructions. The diagnosis must be made on clinical signs and symptoms having a high index of suspicion, and treatment must be based on morphologic investigations, eg, transfemoral phlebography or, preferably, intravascular ultrasound (IVUS). Percutaneous iliac venous balloon venoplasty and stenting is a safe, minimally invasive method with minimal complication rate, no mortality, a 4-year acceptable patency, and substantial sustained clinical improvement. It is a less invasive alternative, and relatively safer than open surgery, and can therefore be offered to a larger group of patients. In case of immediate or late failure venous stenting does not preclude subsequent bypass surgery or surgical correction of reflux when necessary. Although venous stenting is presently the preferred treatment for iliofemoral obstruction, more research is necessary to define accurate hemodynamic criteria for assessment and treatment and to study the long-term effects of stents in the venous system.

INTRODUCTION:

Following successful arterial endovascular surgery, balloon venoplasty and stenting of chronic venous obstructions were introduced in the late 1980s and early 1990s. Most studies of venous stents have reported results of stent treatment of residual obstruction following removal of acute iliac or subclavian vein thrombosis,1,2 or in the venous outflow tract of arteriovenous fistulae used for hemodialysis.3,4 The behavior of venous stents varies greatly depending on indication and anatomic placement of the stents. Assessment of the results of 707 throm bolyzed and stented iliofemoral veins in 24 reports shows primary and assisted primary patency rates varying from 50% to 100% and 63% to 100%, respectively, during a follow-up time of 1 to 46 months. Few of these patients had late follow-up with imaging and no actuarial curves were constructed.5 The primary patency rate following balloon angioplasty without stent and decompression surgery in the subclavian vein after thrombolysis is very poor, as low as 6% at 2 years.6 Owing to its anatomic location, the subclavian vein is prone to flexion during movement, and the vessel may be compressed by external structures, most often between the first rib and clavicle. Stents have been reported to be deformed or even fractured by the forceful compression in the thoracic outlet, resulting in secondary thrombosis.7,8 Although no larger long-term study exists, probably balloon angioplasty and stenting of the subclavian vein should always be combined with decompression surgery.9 The result following angioplasty and stenting of the catheter-induced central vein stenoses and the dialysis access outflow tract of the upper or lower extremities is dismal. The neointimal hyperplasia at the venous anastomosis is very resistant to balloon angioplasty; the primary patency rates at 24 months after angioplasty and stenting for central veins and peripheral veins are only 9% and 17%, respectively.3 The best results have been obtained with treatment of the iliofemoral vein with chronic nonmalignant obstruction. This review will focus mainly upon the symptoms, diagnostic dilemma, technique, and clinical and morphological results (patency and in-stent restenosis rates) after iliofemoral stenting of chronic obstructions.

SYMPTOMS

Symptoms of chronic venous disease may vary greatly, ranging from moderate swelling and pain to discoloration and stasis ulcers. The main emphasis has been on treatment of severe skin changes and stasis ulcer, chiefly by controlling reflux. It is our experience that a substantial number of patients with CVI, however, complain of disabling limb pain and swelling without skin changes.10 These symptoms are not always improved by wearing compression stockings or performing venous valve repair. The dominant pathophysiologic component in these patients may be obstruction rather than reflux, and it is possible that these symptoms are mainly attributable to the outflow blockage. “Venous claudication” is described as an exercise induced “tense” pain, which requires several minutes of rest and leg elevation to subside. Certainly patients with significant outflow obstruction may have less dramatic symptoms, with less distinct lower extremity pain and discomfort, with decreased quality of life and moderate disability. Previous estimations that obstruction is a major contributor in only 10% to 20% of patients with severe chronic venous disease are probably markedly low.

DIAGNOSIS

Often when algorithms are constructed for workup of patients with chronic venous insufficiency, investigations for reflux are emphasized, and testing for outflow obstruction is completely omitted. This is probably owing in part to a lack of accurate objective noninvasive or invasive tests for evaluation of hemodynamically significant chronic venous obstruction, and in part to the lack of practical treatment alternatives prior to the introduction of venous stenting. There are many tests for delineating focal and global reflux but this is not so for outflow obstruction. Ultrasound investigation and outflow fraction determinations by plethysmographic methods have been shown to be unreliable and play only a limited role. Although abnormal plethysmography findings may indicate obstruction to the venous outflow, significant blockage may be present with normal findings.11-13 Even the invasive pressures, ie, hand/foot pressure differential and reactive hyperemia pressure increase, and indirect resistance calculations appear insensitive and do not define the level of obstruction.11 Only a small pressure gradient over a venous stenosis or pressure increase below an obstruction on exercise or hyperemia may indicate significant obstruction. These pressure differences are certainly much lower than in the arterial system, often as low as 2 to 3 mm Hg, which may be difficult to measure accurately.14-16 Thus, although a positive hemodynamic test may indicate hemodynamic significance, a normal test does not exclude it. Unfortunately, it is presently impossible to detect borderline obstructions, which may potentially be of hemodynamic importance. Since accurate hemodynamic tests are unavailable, diagnosis and treatment must be based on morphological findings. Single-plane transfemoral phlebogram is the standard investigation, and may show obstruction and development of collaterals. Increased accuracy may be achieved with multiple angled projections