primary lower extremity deep venous insufficiency
Introduction
Primary lower extremity deep venous valve insufficiency Primary deep venous insufficiency (primary deep valvular insufficiency) is a new category of venous lesions first proposed by Kistner (1980), mainly due to the free edge elongation, relaxation, and sagging of the valve in deep veins, resulting in blood flow under gravity. At the same time, the two opposite leaflets cannot be tightly aligned in the middle of the lumen, causing deep venous reflux disease, resulting in congestion and hypertension of the lower extremity venous system, leading to a series of clinical symptoms and signs. basic knowledge The proportion of illness: 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: thrombotic superficial phlebitis, cellulitis, eczema
Cause
Primary lower extremity deep venous valvular insufficiency etiology
(1) Causes of the disease
The etiology of PDVI is currently accepted by the public. Two universities, namely the venous valve theory and the wall theory, can exist separately or in combination.
Valve theory
(1) Congenital venous valvular dysplasia or deficiency: In 1962, Lindval et al first found that some patients with deep venous insufficiency had similar clinical manifestations and a certain family genetic history, and patients with antegrade and retrograde lower extremity veins During angiography, the wall of the deep venous can be seen to be smooth, and the valve and sinus are lacking. When the Valsalva test is performed, the venous blood flow of the lower extremity is obvious, and the risk of suffering from the disease is as high as 50%. In 1986, Plate et al. Studies have shown that congenital venous valve dysplasia or lack of is an autosomal dominant disease, but the incidence of the disease is low, only 1% to 5%, can not fully explain the majority of PDVI cases.
(2) Valve degeneration and chemistry: Some scholars believe that with the increase of age, the venous valve will undergo tissue degeneration, and the number is reduced, but there is still no strong evidence, which needs further research.
(3) valvular injury theory: primary deep venous insufficiency, occurs in heavy physical labor and long standing, deep venous valve long-term under the gravity of the blood column, subjected to stress, its free edge becomes slack Prolapse, so that the valve has a funnel-like gap when it is combined, and loses the effect of blocking the blood countercurrent. When the countercurrent blood flow passes through the common venous vein with no flap or poor tolerance, the blood column with increased pressure acts on the hidden The valve of the vein, superficial femoral vein and deep femoral vein, because the former is at the highest position, the surface is superficial, and lacks muscle protection, it is most likely to be affected first, while the superficial femoral vein is a direct continuation of the vein, which bears the maximum gravity of the blood column, and often At the same time, it was destroyed. As a result, the deep veins of the calf and the veins of the veins were gradually damaged. Therefore, under the effect of this "domino" effect, the deep and shallow veins of the lower limbs were destroyed. Van Bemmlen et al. confirmed in animal experiments. A venous blood column with increased pressure can destroy the distal venous valve.
2. Wall theory In 1989, Clark et al. studied the elastic coefficient k value of the lower extremity venous wall in the normal group and the disease group, and found that the k value of the normal group was significantly higher than that of the lesion group, indicating that the venous wall of the lesion was elastic. Decreased, the strength is reduced, such a vein wall is expanded under the gravity of the blood column for a long time, and the diameter of the annulus is increased and the relative valve insufficiency occurs. If the time is too long, the valve may be disused or even disappeared. , completely lost the role of preventing blood reflux, domestic Zhang Baigen and other 144 cases of lower extremity varicose veins in the antegrade venography showed that the venous lumen was significantly thickened, the normal shape of the sinus sinus to the bilateral symmetry bulging disappeared, the valve The normal ratio of the sinus transverse diameter to the transverse diameter of the distal vein is lost, and the valve is relatively incompletely closed. In the fatigue test, the contrast agent is retrogradely leaked, and no obvious excessive length or relaxation is found, and Rose et al. Histological observations showed that the valve was not abnormal, but the fibrous tissue in the varicose vein wall increased significantly, destroying the normal arrangement of the muscle bundle, collagen fibers and elastic fibers. Morphological abnormalities occur, which can reduce the elasticity and muscle contraction of the vein wall. In addition, Peagean, Bemmelen et al. also provide strong evidence for the wall theory, the venous wall strength is reduced, so that the venous lumen expands. It is an important reason for PDVI.
(two) pathogenesis
When the deep venous valve is insufficiency, it can cause blood reflux and produce venous hypertension. When the valve surface of the closed valve is located above the iliac vein, the hemodynamic changes can be compensated by the muscle pump of the gastrocnemius muscle. Obvious symptoms, when the lesion passes over the plane of the iliac vein, the blood column pressure is significantly increased due to the long distance of centrifugation. At the same time, the contraction of the gastrocnemius muscle not only promotes blood return, but also strengthens blood reflux, thereby accelerating the destruction of deep veins and penetrating vein valves. Produces obvious symptoms.
Prevention
Primary lower extremity deep venous insufficiency prevention
Avoid long-term standing work, heavy physical labor, pregnancy, chronic cough, habitual constipation and other incentives.
Complication
Primary lower extremity deep venous insufficiency complications Complications, thrombotic superficial phlebitis, cellulitis, eczema
1. Thrombotic superficial phlebitis: slow blood flow in varicose veins, easy to cause thrombosis. Accompanied by infectious phlebitis and varicose veins, can be treated with antibiotics and local heat. After inflammation subsides, local induration often remains. Skin adhesions, after the symptoms have subsided, should be treated with varicose veins.
2. Ulcer formation: The upper foot training area is a part that is far away from the lung and is subjected to high pressure, and has a constant traffic vein. Once the valve function is destroyed, the blood stasis is aggravated, the skin will undergo degenerative changes, and the secondary cell is easily replaced. Wool inflammation, often itchy skin and eczema. After ulceration caused by long-lasting ulcers, mostly complicated by infection.
Symptom
Primary lower extremity deep venous valvular insufficiency symptoms common symptoms pruritus eczema subcutaneous tissue induration varicose veins venous thrombosis
Symptoms and signs similar to simple superficial varices appear, but the larger saphenous veins are more pronounced and severe.
1. Superficial varicose veins: This is the earliest pathological change. The superficial veins along the anatomical distribution of the saphenous vein and/or small saphenous vein are often dilated and elongated, and the stroke is distorted, and some of them may have spherical expansion. The varicose veins can be combined with infection due to slow blood flow, leading to thrombotic superficial phlebitis.
2. Swollen, painful: This is a characteristic manifestation of deep venous insufficiency, venous hypertension, obvious weakness in the lower extremities, soreness, discomfort or pain, sometimes kelp in the calf muscles, uniform swelling of the calf, before sputum There is acupressure edema, symptoms in the afternoon, aggravation when walking, morning, rest, raising the affected limb can be relieved, the symptoms of the summer hot season more frequent.
3. Skin nutrient changes: Skin nutrient changes include skin atrophy, scaling, itching, hyperpigmentation, induration of skin and subcutaneous tissue, eczema and ulceration, and if combined with venous insufficiency in the ankle, these changes can be accelerated The highly dilated superficial vein is susceptible to mild trauma or self-piercing and blood, and it is difficult to stop by itself.
The clinical manifestations of primary deep venous insufficiency are not typical, and the diagnosis must be based on the severity of the hemodynamic changes in the lower extremities and the extent of the lesion.
Lower extremity venous lesions are divided into two categories: blood reflux and reflux disorder. The former is most common with primary deep venous insufficiency and simple saphenous varicose veins, followed by congenital lower extremity deep vein without valve, and full limb lower limbs. The sequelae of deep vein thrombosis are completely recanalized; the latter are mainly sequelae of various types of deep venous thrombosis of the lower extremities, followed by congenital deep vein lesions such as deep vein deficiencies, KTS and iliac vein compression syndrome and lower Venous vein obstruction syndrome, etc., the causes of these lesions are different, but their pathophysiological changes are manifested as different degrees of venous congestion and high pressure, therefore, although their clinical manifestations vary in severity, the symptoms and signs are basically similar The purpose of the examination is to first distinguish between reflux or reflux obstructive lesions, and then further identify the cause and determine the diagnosis in order to provide a reliable basis for the selection of appropriate treatment.
Examine
Primary lower extremity deep venous insufficiency examination
1. Doppler blood flow imaging examination
Nicalaides et al. used an 8MHz continuous waveform blood flow Doppler probe to examine the saphenous vein in the saphenous vein and the saphenous vein. The valve with incomplete function can be accurately found and considered to be a simple and reliable test. method.
2. Vascular ultrasound examination
This is a non-invasive venous system imaging method. The varicose veins are characterized by multiple subcapsular areas under the skin. The blood echo in the duct is extremely low and presents a sound-permeable area. When the proximal or distal end is squeezed, it is squeezed. It can be seen that these small fluid areas are swollen and contracted. The Valsalva breathing method can be used to detect the hemodynamic function of each valve. Measuring the vein diameter when the pressure is suddenly released will help to understand the severity of reflux. The combination of ultrasound and Doppler examination will greatly improve the accuracy of the diagnosis.
3. Plethysmography
The venous blood volume changes were recorded by recording the lower extremity venous volume reduction and venous refill time (VRT). The VRT value was affected by venous valve function and arterial blood flow. The venous valve function was normal, the capillary filling was slow, and if there was reflux The filling is faster and the VRT value is shortened. Therefore, the venous valve insufficiency of the lower extremity can be diagnosed early, the dysfunction of the deep and shallow veins and the traffic valvular valve and the level of reflux can be identified, and the severity of the venous disease can be judged. The diagnosis of qualitative and relative positioning is possible. Function, the specific index is VRT<20s, suggesting the presence of valvular insufficiency. This test can also help to identify venous thrombosis and valvular insufficiency (such as obstructive, flat curve, VRT value is significantly shortened, while reflux disease only shows Shortened for VRT values).
4. Intravenous pressure measurement
As a screening test, it can reflect reflux venous congestion, so as to indirectly understand the function of the valve. Sun Jianmin et al. measured the superficial venous pressure of the standing foot and found that the pressure drop of PDVI patients after exercise was not significant, and the recovery time was shortened after the activity stopped. All of the above indicate that the affected limb is in a state of congestion.
5. Venous angiography
This is the most authoritative examination method for diagnosing PDVI. It can fully understand the severity of hemodynamic changes and the extent of valve damage, so that effective treatment can be divided into two types: venous antegrade and retrograde angiography.
(1) antegrade angiography: mostly used for the examination of obstructive venous disease, injection of contrast agent through the dorsal vein of the foot, PDVI patients can be found, the deep vein of the lower extremity is thickened, the whole process is smooth, the wall is smooth, intact, and the superficial vein system is also expanded. When the contrast agent is refluxed in the deep vein, it can be transferred to the superficial vein through the tributary to the superficial vein. When the Valsalva technique is used, the position of the valve loses the shape of the external bulging, no contrast is blocked, and there is no contrast agent on the far side. Diluted and the degree of blockage is reduced.
(2) Retrograde angiography: a common method for checking valve dysfunction and blood reflux. Direct injection of contrast agent into the femoral vein at the groin. According to the Kistner criteria, the valve function is graded as follows:
Level 0: When breathing calmly, no contrast agent leaks distally through the valve.
Grade I: Only a small amount of contrast agent leaks through the highest pair of valves in the superficial femoral vein, but does not exceed the proximal section of the thigh.
Grade II: The mild contrast agent flows back through the valve to the axillary plane.
Grade III: A large amount of contrast agent flows back through the valve to the calf.
Grade IV: The contrast agent is directed back to the ankle.
Grade 0, the deep venous valve is closed normally; the grade III needs to be combined with the clinical manifestation to judge the venous valve closure function; the grade IIIIV can diagnose the deep venous valve insufficiency.
5. Venous venous catheter angiography
(Functional detection of deep venous valve function of lower extremities) In the mid-1980s, the vascular surgery of the Ninth People's Hospital affiliated to Shanghai Second Medical University passed clinical observation and found that some patients had obvious and serious clinical manifestations. The angiography was diagnosed as primary deep venous insufficiency of the lower extremity, but the retrograde angiography was grade O, and the contrast agent was blocked in the first pair of valves of the femoral vein. Therefore, the iliac vein catheterization examination was started to locate the detection unit. In the function of each pair of valves in the iliac vein, the iliac vein is located in the center of the diamond-shaped armpit consisting of the biceps, semitendinosus and gastrocnemius, and the lateral head. The dorsal surface has fascia and axillary fat. The pad is proximal to the superficial femoral vein in the fascia; the distal end is divided into the anterior and iliac veins, and the iliac vein is flanked by the radial artery and the phrenic nerve, which are parallel to the median line of the axillary fossa. The trend is that the radial artery is located in the ventral medial aspect of the iliac vein, and the phrenic nerve is located on the dorsolateral side of the iliac vein. The iliac vein is generally located according to the anatomical projection of the radial artery. The proximal end of the radial artery is located in the scapular nodule. Above 7.6cm, 1cm inside the median line of the armpit; the distal end is 2.5cm below the plane of the humeral head, 1cm outside the median line, and the line between the above 2 points is the surface projection of the radial artery, because the iliac vein and the iliac vein The artery is accompanied by, so the parallel line made about 0.5cm outside the line is the surface projection of the iliac vein. A simpler method is to move the midline of the armpit slightly counterclockwise to make it The lower end is about 1 cm away from the original position. This line is the middle line separating the turbulence and the vein. The inner side of the line is 0.5 cm for the radial artery, and the outer side of the line is 0.5 cm for the projection of the iliac vein.
During angiography, the patient is lying prone, and a pillow or soft pad is placed on the neck and chest to reduce the discomfort such as swell of the chest when lying down. The puncture point is 0.5 to 1 cm outside the intersection of the median line of the armpit and the transverse wrinkles of the armpit skin. Or on the lateral wrinkles of the axillary skin, the needle is inserted 0.5 to 1 cm outside the pulsation of the artery. The specific method is to first mark the puncture site on the skin with methylene blue, and use the pointed scalpel according to the routine before surgery. Pierce the skin of the puncture point, the Seldinger puncture needle is 45° to the limb, and penetrates proximally. When passing through the fascia fascia, there is a clear sense of piercing, and then slowly penetrate into the deep, when the needle tip touches the surface of the brachial artery. Relax the puncture needle to see the needle body pulsing up and down with the artery pulsation. At this time, the needle tip should be slightly moved to the outside and then the needle should be inserted. When the sensation has penetrated the iliac vein, it is necessary to stop the needle and pull out the needle. After the core, there is a dark red vein blood flow; if no blood flows out, it means that the vein is not penetrated, the needle can be slightly pulled out, and then puncture in different directions, such as the red blood of the blood vessel, indicating the needle Has been mistaken At this time, the puncture needle should be pulled out of the body, partially compressed for 10 minutes, and then re-pierced; when the puncture needle enters the iliac vein, the venous catheter is inserted into the iliac-femoral vein through the guiding wire; the patient is placed at 60° High and low position, inject 10 to 15 ml of contrast medium once, observe whether the inferior and iliac veins are unobstructed; then slowly pull out the venous catheter and continue to inject a small amount of contrast agent to show each pair of valves (due to the valve socket) There is contrast agent deposition, which can make the valve develop); every time a pair of valves is found, the function of the valve is detected, and whether there is blood backflow, the tip of the intravenous catheter is placed 0.5cm below the valve, and the contrast agent is injected about 5ml. When the contrast agent is completely returned to the proximal side of the valve, the patient is immediately forced to hold the breath. If the valve is in good function, the local part is bamboo-like bulging. The contrast agent is blocked by the valve and cannot flow to the distal side. If the valve is incomplete , the contrast agent can be seen to flow backwards; thus, from the proximal side to the distal side, that is, from the iliac vein to the iliac vein, the function of each pair of valves is detected one by one, and X-ray images are taken separately, or the whole process of the examination is recorded. .
Deep venous angiography of the lower extremities often does not clearly show the iliac vein; in retrograde angiography, if the first valve of the superficial femoral vein is functional, it is impossible to further examine the function of the distal valve-by-valve, and iliac vein catheterization is solved. These shortcomings and deficiencies can completely replace retrograde angiography. In addition, for deep veins of the lower extremities, especially those with stenosis of femoral-femoral and femoral-venous venous thrombosis, as long as the iliac vein is not involved or has been recanalized, it can be done. Venous cannulation, the venous catheter is placed close to the distal end of the lesion to perform angiography, which can clearly show the lesion and collateral circulation.
According to clinical practice, Kistner's 5-level classification of the reverse flow range is important in clinical practice. However, when the valve function is detected, the amount of contrast agent crossing the valve leakage is more indicative of the severity of valve damage and reflux disease. Therefore, the degree of backflow is divided into light, medium and heavy grades. Where the patient continues to hold the breath for more than 5s, there is a small amount of contrast agent in the form of a line-like leakage, which is mild backflow; after holding for 3s, the contrast agent is to the far side of the valve. Backflow, and faster filling of the distal venous segment of the valve, is a moderate reflux; slightly breath holding or no breath holding, the contrast agent is directly backflow, the valve is near, the contrast agent in the distal vein segment shows almost or exactly the same concentration It is a severe reflux, and the range of backward flow belongs to Kistner III and IV. It is the indication for deep venous valve reconstruction. Light, moderate reflux and severe reflux are reliable for different procedures in deep venous valve reconstruction. in accordance with.
6. Variegated superficial venography
The patient is erect, so that the superficial veins of the varicose veins are filled. In the site where the examination is needed, such as the presence of a traffic vein as shown in the anatomy, or the varicose vein is particularly obvious, the superficial vein of the varicose vein is directly puncture with a 7-gauge needle; the patient is placed flat on the X-ray. Check the bed, the head high and low 15 ° ~ 30 °, the sputum does not tie the tourniquet, continue to inject contrast agent, trace the contrast of the contrast agent with the blood through the TV screen, and change the patient's position at any time, such as lying on the side, prone Etc., or change the examination table to a horizontal position or a low position; if a traffic vein with a suspicious function is found, a tourniquet can be added to the proximal side to clearly show the superficial vein or the traffic vein; And need to puncture the superficial veins of different parts for angiography, and take X-ray films, varicose superficial venography can clearly show the traffic veins of the limbs with insufficiency, especially the expansion around the ulcer, distortion and thickening of the traffic veins, Traffic veins that show lesions in the knees and thighs serve as a basis for guiding surgery.
Diagnosis
Diagnosis and diagnosis of primary deep venous valve insufficiency
Diagnostic criteria
1. Most of them are long-term standing and strong physical labor, or the symptoms of saphenous vein exfoliation have not improved or short-term recurrence.
2. The affected limb is swollen, and there is swelling and severe pain when standing for a long time. Symptoms and signs of simple varicose veins of the lower extremities.
3. Intravenous pressure measurement, directional Doppler ultrasonography is helpful for diagnosis.
4. Venous angiography.
Differential diagnosis
1. Deep vein thrombosis syndrome: patients with more than surgery, trauma or long-term bed rest after pregnancy, a history of thrombosis, early thrombotic obstructive lesions, early thrombus recanalization, venous valve destruction, and It is characterized by reflux disease. The patient presents with a wide range of uniform swelling of the lower extremities, accompanied by tenderness of the gastrocnemius and the trigone. In severe cases, the arterial system can be involved. The dorsal artery and posterior tibial artery are weakened, and the femoral bruises disappear. Sometimes it is difficult to identify with PDVI in the later stage of the disease, and venography can help to determine the diagnosis.
2. Simple lower extremity superficial varicose veins: The clinical symptoms are mild, which is characterized by the heavy feeling of lower limbs and fatigue. The superficial venous system is distorted and dilated. In the later stage of the disease, when the traffic valvular valve is damaged, there may be nutritional changes in the foot boot area, such as skin. Desquamation, pigmentation, eczema and ulcer formation, generally no severe swelling and severe swelling pain, venography can be seen that the deep vein system is completely normal.
3. Klippel-Trénaunay syndrome: It is a congenital venous malformation, which is rare in clinical practice. Patients have typical triad disorders: thickening of limbs, superficial varicose veins and vasospasm of the skin, which is generally not difficult to identify.
4. Limb lymphedema: It is caused by lymphatic vessel damage or other causes of lymphatic vessels, lymph node defects, and lymphatic retention. In the early stage of the lesion, it is located in the depression below the knee joint, and the skin becomes rougher, thicker and harder. It is a mass, easy to be associated with erysipelas infection, and lymphangiography is helpful for differential diagnosis.
