Obliterating diseases of this type most often occur due to atherosclerosis of arteries, obliterating thromboangiitis (endarteritis), aortoarteritis, fibro muscular dysplasia. They are the main cause of peripheral arterial insufficiency in the lower limbs.
Symptoms of obliterating diseases of lower limb arteries
Constriction and obliteration of the arteries:
causes a sharp weakening of the blood flow,
impairs blood circulation in the vessels of the microvasculature,
reduces oxygen delivery to tissues,
causes tissue hypoxia and impaired tissue metabolism.
The latter worsens due to the opening of the arterio-venular anastomoses. The decrease in oxygen tension in the tissues leads to the accumulation of oxidized metabolites and metabolic acidosis. Under these conditions, adhesion and aggregation increase and the disaggregation properties of platelets decrease, the aggregation of erythrocytes increases, blood viscosity increases, which inevitably leads to hypercoagulation and the formation of blood clots. Blood clots in diseases of the lower limb arteries block the microcirculatory bed, exacerbating the degree of ischemia of the affected organ. Against this background, disseminated intravascular coagulation develops.
Activation of macrophages, neutrophilic leukocytes, lymphocytes and endothelium cells is accompanied by the release of proinflammatory cytokines (IL-1, IL-6, IL-8, TNF), which play an important role in regulating the microcirculatory blood circulation, increasing capillary permeability, in vascular thrombosis, damage (necrosis) of tissues by active oxygen radicals. The tissues increase the content of histamine, serotonin, prostaglandins, which have a membrane-toxic effect.
Chronic hypoxia against arterial disease leads to the breakdown of lysosomes and the release of hydrolases that lyse cells and tissues. The body is sensitized by the breakdown products of proteins. There are pathological autoimmune processes that aggravate microcirculation disorders and increase local hypoxia and tissue necrosis.
Stage of obliterating arterial diseases
Depending on the degree of insufficiency of the arterial blood supply to the affected limb, four stages of the disease are distinguished (according to the Fontaine — Pokrovsky classification).
Stage I . Patients noted chilliness, cramps and paresthesias in the lower extremities, sometimes tingling and burning in the fingertips, increased fatigue, fatigue. When cooled, the limbs become pale and cold to the touch. In the mid-flight test after 500-1000 m, intermittent claudication occurs. In order to standardize the marching test, the patient is recommended to move at a speed of 2 steps per second (by metronome). Determined by the length of the path traveled before the appearance of pain in the gastrocnemius muscle and the time until the complete inability to continue to walk. Sample is convenient to carry out on tredbane. According to the march test indicators, one can judge the progression of the disease and the success of the treatment. Intermittent claudication occurs due to insufficient blood supply to the muscles, impaired oxygen utilization, accumulation in the tissues of oxidized metabolic products.
Stage II arterial occlusive disease – subcompensation. The intensity of intermittent claudication is increasing. At the indicated pace of walking, it occurs already after overcoming the distance of 200–250 m (Pa stage) or somewhat less (116 stage). The skin of the feet and legs loses its inherent elasticity, becomes dry, flaky, and hyperkeratosis is detected on the plantar surface. The growth of nails slows down, they thicken, become brittle, dull, acquiring a matte or brown color. Disturbed and growth of hair on the affected limb, which leads to the appearance of areas of baldness. Atrophy of subcutaneous fat and small muscles of the foot begins to develop.
Stage III – decompensation. Pain in rest appears in the affected limb, walking becomes possible only at a distance of 25-50 m. The skin color changes dramatically depending on the position of the affected limb: when lifting, its skin turns pale, when lowering, redness of the skin appears, it becomes thinner and becomes thin. Minor injuries due to scuffs, bruises, nail clippings lead to the formation of cracks and superficial painful ulcers. Atrophy of the muscles of the leg and foot. Disability significantly reduced. In severe pain syndrome to relieve suffering, patients take a forced position – lying with their legs down.
Stage IV Obliterative arterial disease – destructive changes. Pain in the foot and fingers become permanent and unbearable. The resulting ulcers are usually located in the distal extremities, often on the fingers. The edges and the bottom of them are covered with a dirty gray bloom, there are no granulations, there is inflammatory infiltration around them; joins swelling of the foot and lower leg. The developing gangrene of the fingers and feet often proceeds according to the type of wet gangrene. Disability in this stage is completely lost.
The level of occlusion leaves a definite imprint on the clinical manifestations of the disease. The lesion of the femoral popliteal segment is characterized by low intermittent claudication – the appearance of pain in the calf muscles. Atherosclerotic lesions of the terminal part of the abdominal aorta and iliac arteries (Leriche syndrome) are characterized by high intermittent claudication (pain in the gluteus muscles, in the muscles of the thighs and the hip joint), muscle atrophy of the leg, impotence, reduction or absence of pulse in the femoral artery. Impotence is caused by impaired blood circulation in the system of the internal iliac arteries. It occurs in 50% of observations. It occupies a minor place among other causes of impotence. In some patients with Leriche syndrome, the skin of the extremities acquires ivory color, there are patches of baldness on the thighs, hypotrophy of the muscles of the extremities becomes more pronounced, sometimes they complain of pain in the umbilical region that occurs during exercise. These pains are associated with the switching of blood flow from the mesenteric artery system to the femoral artery system, that is, with the syndrome of mesenteric steal.
Diagnosis of arterial disease obliterans
In most cases, the correct diagnosis can be established using conventional clinical examination, and special research methods, as a rule, only detail it. Planning to conduct conservative therapy, with proper use of clinical methods, you can abandon a number of instrumental studies. Instrumental diagnostics has undoubted priority in the period of preoperative preparation, during surgery and postoperative observation.
Inspection gives valuable information about the nature of the pathological process. In chronic obliterating disease usually:
developing muscular hypotrophy,
filling of the saphenous veins decreases (a symptom of a groove or a dried riverbed),
skin color changes (paleness, marbling, etc.).
Then there are trophic disorders in the form of hair loss, dry skin, thickening and brittle nails, etc.
In severe ischemia, blisters appear on the skin, filled with serous fluid. Often there is dry (mummification) or wet (wet gangrene) necrosis of the distal limb segments.
Significant information on the localization of arterial occlusive disease is given by palpation and auscultation of the leg vessels. Thus, the absence of a pulse in the popliteal artery indicates obliteration of the femoral-popliteal segment, and the disappearance of the pulse on the thigh indicates defeat of the iliac arteries. In a number of patients with high occlusion of the abdominal aorta, pulsation cannot be detected even with aortic palpation through the anterior abdominal wall. In 80–85% of patients with obliterating atherosclerosis, the pulse is not detected on the popliteal artery, and in 30%, on the femoral artery. It should be remembered that in a small number of patients (10-15%) there may be an isolated lesion of the vessels of the leg or foot (distal form). All patients need to conduct auscultation of the femoral, iliac arteries and abdominal aorta. Systolic murmurs are usually heard above the stenotic arteries. With stenosis of the abdominal aorta and the iliac arteries, it can be well defined not only above the anterior abdominal wall, but also on the femoral arteries under the inguinal ligament.
Selective damage to the distal arteries is the reason that in patients with thromboangiitis obliterans, the pulsation of the arteries on the feet in the first place disappears. At the same time, it should be borne in mind that in 6-25% of practically healthy people the pulse on the dorsal artery of the foot may not be determined due to anomalies of its position. Therefore, a more reliable sign of the disease is the absence of a pulse on the posterior tibial artery, the anatomical position of which is not so variable.
Diagnostic criteria for obliterating diseases of the arteries of the legs
Symptom of plantar ischemia consists in blanching the sole of the foot of the affected limb, raised up at a 45 ° angle. Depending on the speed of blanching, you can judge the degree of circulatory disorders in the limb. In severe form of the disease it occurs within 4-6 s. Later, changes were made to the sample of Goldflam and Samuels, allowing to more accurately judge the time of the appearance of blanching and restoration of blood circulation. In the supine position, the patient is offered to raise both legs and hold them at a right angle at the hip joint. For 1 min, it is suggested to bend and unbend the feet in the ankle joint. Determine the time of occurrence of blanching feet. Then the patient is offered to quickly take a sitting position with his legs down and note the time until the veins are filled and reactive hyperemia appears. The data obtained are amenable to digital processing, provide an opportunity to judge the change in blood circulation during treatment.
Goldflame Test in the diagnosis of obliterating arterial diseases. In the position of the patient on his back with his legs elevated above the bed, he is offered to make flexion and extension in the ankle joints. When blood circulation is disturbed, after 10–20 movements, the patient experiences fatigue in the leg. At the same time, the staining of the sole of the foot is monitored (Samuels sample). In severe blood supply insufficiency, blanching of the feet occurs within a few seconds.
Test Sitenko-Shamova held in the same position. A tourniquet is applied to the upper third of the thigh until the arteries are completely clamped. After 5 min, the bandage is removed. Normally, no later than 10 seconds, reactive hyperemia appears. In case of insufficiency of the arterial blood circulation, the time of appearance of reactive hyperemia is extended several times.
Panchenko Knee Phenomenon determined in sitting position. The patient, having thrown back his sore leg on the knee of a healthy one, soon begins to experience pain in the calf muscles, a feeling of numbness in the foot, a feeling of crawling in the crawls in the fingertips of the affected limb.
Symptom of compression of the nail bed lies in the fact that during compression of the terminal phalanx of the first toe in the anteroposterior direction for 5-10 seconds in healthy people, the resulting blanching of the nail bed is immediately replaced by a normal color. When blood circulation in the limb is impaired, it lasts for several seconds. In cases where the nail plate is changed, it is not the nail bed that is squeezed, but the nail roller. In patients with impaired peripheral blood circulation, a white spot formed as a result of compression disappears slowly, over several seconds and more.
Instrumental methods of diagnosis of obliterating arterial diseases
Rheography, Doppler ultrasound, transcutaneous determination of p0 help to establish the degree of ischemia of the lower limb2 and pC02 lower limbs.
For obliterating lesions are characterized by a decrease in the amplitude of the main wave of the eographically curve, the smoothness of its contours, the disappearance of additional waves, a significant decrease in the value of the eographically index. The reograms recorded from the distal parts of the affected limb during circulatory decompensation are straight lines.
Doppler ultrasound data usually indicates a decrease in regional pressure and linear blood flow velocity in the distal segments of the affected limb, a change in the blood flow velocity curve (the so-called trunk-altered or collateral blood flow is recorded), a decrease in the ankle systolic pressure index, which is derived from the ratio of systolic pressure to ankle to pressure on the shoulder.
Using ultrasound duplex diagnostics in patients with Leriche syndrome, it is possible to clearly visualize changes in the terminal part of the abdominal aorta and iliac arteries, occlusion or stenosis of the femoral, popliteal artery, determine the nature and duration of damage in the main collateral arteries (in particular, in the deep femoral artery). Diagnosis allows to determine the localization and extent of the pathological process, the degree of arterial lesion (occlusion, stenosis), the nature of changes in hemodynamics, collateral circulation, the state of the distal bloodstream.
Verification of a topical diagnosis is performed using angiography (traditional radiopaque, MR or CT angiography), the most informative diagnostic method.
Angiographic symptoms of obliterating diseases of lower limb arteries include marginal filling defects, edema of the vessel wall contours with stenosis, the presence of segmental or widespread occlusions with filling of the distal sections through a network of collaterals.
When thromboangi on the angiograms determine the good permeability of the aorta, the iliac and femoral arteries, the conical narrowing of the distal segment of the popliteal artery or the proximal segments of the tibial arteries, obliteration of the arteries of the leg on the rest of the network with a network of multiple, small, convoluted collateral. The femoral artery, if it is involved in the pathological process, appears to be evenly narrowed. It is characteristic that the contours of the affected vessels, as a rule, are even.
Features of the treatment of obliterating diseases of the arteries of the lower extremities
Indications for performing reconstructive operations for segmental lesions of the arteries can be determined starting from the PB stage of the disease. Contraindications are severe concomitant diseases of internal organs:
heart, lungs, kidneys, etc.,
total calcification of arteries,
lack of patency of the distal bed.
Restoration of the main blood flow in the arteries is achieved using endarterectomy, bypass shunting or prosthetics. When obliteration of the arteries of the lower extremities in the femoral-popliteal segment perform femoral-popliteal or femoral-tibial shunting segment of the great saphenous vein. The small diameter of the great saphenous vein (less than 4 mm), early branching, varicose expansion, phlebosclerosis limit its use for plastic purposes. As a plastic material in the treatment of used umbilical cord vein of the newborn, allovenous grafts, lyophilized xenografts from cattle arteries. Synthetic prostheses are of limited use in the treatment of obliterating arterial diseases, as they are often thrombosed as soon as possible after surgery. In the femoral-popliteal position, polytetrafluoroethylene prostheses proved to be the best.
In atherosclerotic lesions of the abdominal aorta and iliac arteries, aortic-femoral bypass surgery or resection of the aortic bifurcation and prosthetic repair using a synthetic bifurcation prosthesis is performed. If necessary, surgery for the treatment of arteries can be completed by excision of necrotic tissue.
In recent years, endovascular dilatation and lumen retention of a dilated vessel with the help of a special metal stent have become widely used in treatment. The method is quite effective in the treatment of segmental atherosclerotic occlusion and stenosis of the femoral-popliteal segment and the iliac arteries. It is also successfully used as a supplement to reconstructive surgeries, in the treatment of multi-storey lesions.
In diabetic macroangiopathies, reconstructive surgeries can not only restore the main blood flow, but also improve blood circulation in the microvasculature. Due to the defeat of the arteries of small diameter, as well as the prevalence of the process, reconstructive operations for thromboangiitis obliterans have limited use.