Anatomy & Physiology

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ANATOMY and PHYSIOLOGY

Figure 1

Fig 1- Simple schematic representation of Circulation (Click to enlarge)

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The heart pumps oxygen rich blood to everywhere in the body via  high-pressure pulsating blood vessels named arteries. Like arteries, veins are tube shaped too, however, they are low pressure blood vessels that bring blood back to the heart (Fig.1). Veins localized above the level of the heart have relatively an easy task, as gravity will help blood returning to the heart. Veins localized below the level of the heart, as in the legs, have a major problem as blood has to return uphill, against gravity, a quite difficult task. It is mainly the calf (gastrocnemius/"gastroc") muscle pump pressure during the walking cycle's “heel up” position that pushes blood uphill, back to the heart, therefore waking is very healthy promoting physiologic uphill flow that will decongest a distended superficial venous system and also lower the venous pressure.

Without going into too many details, all our leg and arm veins have two venous systems : one deep and one superficial, just beneath the skin. Both systems have  valves or gates (similar to a system of locks on a dam) that should normally permit only unidirectional uphill  (back to the heart) flow.

Figure 2

Fig. 2. Normal vein and properly closing valves: uphill (back to the heart) flow possible. (Click to enlarge)

Please imagine the Panama Canal: locks open, ship goes through, locks close, ship can go forward only, another lock opens, ship goes through and so on... and so on…

Each valve is made off to leaflets. Each of them is attached to the vein wall while the leaflets meet in the middle.

In a normal vein, during the “heel-up” position of the walking cycle, the increased pressure exerted by the calf muscle on the veins will open the valve’s two leaflets and blood is pushed uphill. (Fig. 2) With cessation of the calf muscle pressure in the “foot-down” position of the walking cycle, the pressure drops, the leaflets immediately close and the blood that was pushed uphill remains up (Fig. 3)!!!  meaning that blood that reached already the thigh is unable to return (tumble by gravity) to ankle, not even knee and not even if one strains with all force! Never!! This is what a normal and competent valve is. Uphill/upward yes, downhill/downward, NEVER!

Figure 3

Fig 3. Normal vein, normal closing (competent) valve; downward/reversed flow (reflux) by gravity NOT possible!

Varicose veins is a disease of the meagerly supported (mainly skin) superficial leg veins caused by a possible inherited family tendency of a vein wall weakness. I famed Canadian physician considered to be the father of modern medicine, Dr. William Osler said well over 100 hundred years ago: "Varicose Veins are result of improper selection of grand parents" but lease take "grand parents loosely...  By definition, they are enlarged, distended, stretched and tortuous veins that can be localized everywhere on the leg. (Please note, deep vein varicosities do not exist possibly  because the good muscular support they have!)

Once the vein got larger the two opposing valve leaflets existing in its lumen become separated (pulled sideways) and unable to properly function. Basically, they can’t anymore close the oversized vein. While blood is pushed up during the “heel-up” position of the walking cycle, as the pressure drops in the “foot-down” position, everything that has been pushed up comes back by simple gravity. (Fig. 4 and 4A). These valves are called incompetent or insufficient as they leak and the volume of blood surging downhill is called reflux or regurgitation.

We have in our legs two venous system: one deep (not visible) in the muscles, and one superficial (visible) just under the skin. From the functional point of view the deep system is carrying most of the blood back to the heart (80%) thus it is the most important system of the two.

Figure 4

Fig 4. Diseased vein with non-closing valves. Downward/reversed gravitational flow (reflux) a norm...

There are also two sets of superficial venous systems in each leg: a long one (called long or greater saphenous vein) localized along the entire inner aspect of the leg from the ankle to the groin; and a short one (short or small saphenous) system localized in the hind side of the calf also from the ankle to just behind the knee. In the groin and behind the knee the two main superficial vein trunks (also called axial veins) join, basically dead-end in the deep vein trunks. These two anatomic sites are called junctions: (SFJ or Sapheno Femoral Junction) in the groin and (SPJ or Sapheno-Popliteal Junction) behind the knee. (Fig 5). These crucial sites when they leak will permit blood from the deep veins to escape / tumble by gravity down the leg via the axial veins and through them into the existing branch/tributary varicosities of the thigh, calf or both.  Therefore, any therapeutic modality has to start here, as these two leaky proximal valves (also called escape points) have to be controlled/closed in one way or another exactly as one would close a leaky faucet causing flooding of the floor. Only that way will blood from the deep vein be stopped into spilling over onto the superficial varicose system. Failure to properly close any of the incompetent junctions will end in procedures quite early failure.

Fig.4b

Fig. 4A-Normal (uphill) and reversed (downhill) flow in a varicose vein. (Click to enlarge)

In summary, in varicose veins part of the blood normally flowing upward in the deep veins will escape through one of the two incompetent junctions (SFJ or SPJ) into an also incompetent superficial axial saphenous veins (long or short) and start flowing downward towards the feet and ankle while also filling with blood (flooding) the distended/varicose  branches (tributaries) of the axial vein existing in the thigh, calf or both. With passage of time these branches will become even further distended.  This is the pathway of incompetence.

Figure 5

The short and long saphenous veins with the two junctions
SPJ (behind the knee) and SFJ (at the groin) Click to enlarge.

With cessation of gravitational forces (horizontal position or even better with elevated legs) blood in the varicose veins will again resume their physiologic uphill flow and will  "disappear" from sight.  Just do it on yourself: lie down, elevate your varicose leg and see the bulging vein "disappear". Of course, by resuming an upright position they will bulge/protrude again. This is the reason that elevation is so healthy and that during nighttime compression is never needed.

During your first consultation the practitioner will have to map the above mentioned pathway of incompetence by clinical and non-invasive obligatory diagnostic tests such as Doppler ultrasound sonography even better duplex imaging. If no such test was performed please change practitioner. Run away also, even faster, if the test was done in a horizontal position only. Reflux/regurgitation/reversal of  flow in varicose veins is gravity dependent and you need be examined in an upright position!! Moreover, it is optimal that the ultrasound test be performed by the practitioner responsible for the results. If you have been farmed out to an Radiology/imaging center, the results are on a paper only and if the technician made a mistake so will the practitioner and the expected results may not be there..

Varicose veins are more prevalent in the female population undoubtedly because pregnancies. Symptoms if present are mainly ankle swelling at end of the day, discomfort and pain.

Figure 6

Fig 6. Patient with long saphenous varicose veins causing Chronic Venous Insufficiency. She had surgery and further deterioration was prevented however the discoloration will persist...

Complications are blood clots/phlebitis usually far less dangerous as a superficial clot - contrary to a deep vein one – is well attached to the vein wall thus rarely gets to float into the circulation. Treatment is simple evacuation of the clot under local anesthesia, local compression and over the counter NSAID drugs.

A much more severe complication is the result of long-term neglect. Indeed the long term elevated venous pressure existing in the varicose veins will be responsible for microcirculatory changes in the skin as seen in chronic venous insufficiency (CVI): namely brown, indurated, eczematous skin (Fig. 6) that can further progress to venous ulceration which could be a much debilitating condition and sometimes difficult to treat.