Arterial insufficiency

Among diseases of the circulatory system and pathological conditions of blood vessels (angiopathies), the first place is occupied by arterial insufficiency, in which the blood flow through the arteries slows down or stops.

Epidemiology

According to some studies, various forms of arterial insufficiency with impaired arterial circulation are present in 17% of the population over 55 years of age. Angiopathy of the lower extremities affects about 13% of the population under 70 years of age and 20% of the population over 75 years of age. And acute limb ischemia mainly affects the elderly as well.

It is also noted that after the age of 60, 40-50% of patients with severe limb arterial insufficiency have arterial insufficiency syndrome with associated coronary heart disease (CHD) and strokes.

Causes of the arterial insufficiency

In the vast majority of cases, the etiology of arterial insufficiency is related to narrowing or blockage of the arterial lumen due to the accumulation of atherosclerotic plaques on their walls and thrombus or embolus formation during the development of stenosing atherosclerosis.

The localization of arterial insufficiency is determined:

• Lower extremity vascular atherosclerosis, that is, lower extremity atherosclerotic angiopathy, which is diagnosed as a disease of the peripheral vessels of the legs;
• coronary atherosclerosis - atherosclerosis of the vessels of the heart;
• Cervical vascular atherosclerosis;
• renal artery atherosclerosis;
• atherosclerosis of the abdominal aorta and its branches.

In addition, rarer causes of arterial blood flow insufficiency of various localizations include:

• affecting small arterial vessels non-atheromatous arteriosclerosis (in patients with diabetes);
• Autoimmune inflammation of the walls of the aorta and its branches (subclavian, carotid, vertebral arteries) - non-specific aortoarteritis (Takayasu's disease);
• Inflammatory thrombosis of small and medium-sized arteries - obliterative thrombangiitis or obliterative endarteritis;
• Deposition of abnormal glycoprotein (amyloid) in vessel walls in amyloidosis of any origin.

Patients with antiphospholipid syndrome often have a combination of arterial and venous insufficiency, which is due to thrombus occlusion of peripheral veins and small-diameter arterial vessels.

Risk factors

The most important risk factors include: disorders of lipid metabolism with hyperlipidemia, elevated blood cholesterol levels - hypercholesterolemia, arterial hypertension, diabetes, smoking, obesity, family history of arterial insufficiency, and advanced age.

Pathogenesis

In atherosclerosis, the pathogenesis of arterial insufficiency is explained by atherothrombotic narrowing of the arterial lumen and their occlusion, which occurs when atherosclerotic plaques form on the inner wall of the vessel. The vessel lumen is also blocked by a thrombus, which is formed when the plaque ruptures.

This leads to negative changes in the circulatory system: insufficient perfusion (blood flow), ischemia (localized delay of blood supply) and deterioration of tissue trophism with the development of hypoxia (oxygen deficiency).

In case of insufficient perfusion, tissue cells switch to anaerobic metabolism, producing lactate (lactic acid); an increase in lactate disrupts the acid-base state of the blood, reducing its pH. As a result, lactoacidosis develops and the amount of oxygen molecules with increased reactivity - free radicals - increases.

And the action of free radicals provokes oxidative stress - with disruption of the normal redox state of cells and damage to their components, which can cause cell death and tissue necrosis. [1]

Symptoms of the arterial insufficiency

The symptoms of arterial insufficiency depend on where the vessel is narrowed or its lumen is blocked (stenosis or occlusion). If the coronary arteries are affected, chest pain (angina pectoris) may occur.

In arterial insufficiency of the carotid arteries that supply blood to the brain, the first signs may be frequent dizziness, short-term loss of balance, headaches, and paresthesia (numbness) of parts of the face.

If patients with atherosclerosis obliterans or nonspecific aortoarteritis have decreased blood flow in the visceral arteries (glomerular trunk and superior mesenteric artery) and abdominal aorta, chronic arterial insufficiency manifests itself with abdominal pain after meals, flatulence, constipation or diarrhea. This condition may be defined as chronic mesenteric ischemia, and as ischemic bowel disease.

But more commonly diagnosed and best studied ischemia of the extremities - their chronic and acute vascular insufficiency.

Acute arterial insufficiency of the lower extremities leads to their acute ischemia and is manifested by pain in the legs at rest, pallor of the skin and absence of pulse, paresthesia and paralysis.

In case of lower extremity obliterative disease chronic arterial insufficiency of the extremities is manifested by such angiopathic symptoms as cold sensation in the lower leg or foot, weakened or absent pulse in the feet, numbness or weakness in the legs, painful cramps in the calf muscles after walking or climbing stairs, and intermittent claudication. [2]

Depending on the presence of symptoms, degrees or stages of chronic arterial insufficiency are defined according to Fontaine (Fontaine, 1954):

• Grade 1 arterial insufficiency: no symptoms;
• Grade 2 arterial insufficiency: stage 2A has mild intermittent claudication when walking, stage 2B has moderate to severe claudication;
• Grade 3 arterial insufficiency: pain in the legs at rest;
• Grade 4 arterial insufficiency: presence of tissue necrosis and/or gangrene.

Stages of ischemia of the lower extremities, which gives the classification according to Pokrovsky (classification of Fontein in modification of A.V. Pokrovsky) are divided by the severity of intermittent claudication, but to determine in patients with stage 1 of the disease should be present pain in the legs during exercise and prolonged walking.

In addition, experts distinguish the syndrome of vertebrobasilar arterial insufficiency or vertebral-basilar insufficiency, which occurs with atherosclerotic lesions of the vertebral and basilar arteries that provide blood supply to the brain stem, cerebellum and occipital lobes of the brain.

Symptoms of this condition may include dizziness, loss of balance and coordination, pain in the back of the head, numbness or tingling in the hands or feet, nausea and vomiting, sudden severe weakness throughout the body, transient diplopia (double vision) or loss of vision (single or bilateral), speech impairment, dysphagia (difficulty swallowing), confusion or loss of consciousness. [3]

Complications and consequences

Disruption of blood supply in arterial insufficiency leads to the development of ischemic neuropathy. For example, if blood flow in the extracranial arteries of the head and neck deteriorates, patients face such a complication as ischemic optic neuropathy.

Atherosclerotic changes in the cerebral arteries that lead to their insufficiency may be complicated by transient cerebral ischemia (transient ischemic attacks) or ischemic stroke. A complication of impaired coronary blood flow is coronary heart disease.

The consequence of arterial insufficiency of the vessels of the lower extremities can be arterial trophic ulcers and dry gangrene (often with the need to amputate part of the leg).

And chronic ischemic kidney disease (ischemic nephropathy) is the result of arterial insufficiency with hemodynamically significant atherosclerotic stenosis of renal arteries with secondary complications in the form of poorly controlled hypertension, as well as progressive nephrosclerosis, which is fraught with renal failure. [4]

Diagnostics of the arterial insufficiency

Diagnosis of arterial insufficiency requires a complete patient history and a comprehensive examination with arterial examination.

General and biochemical blood tests are taken; the blood levels of total cholesterol, LDL, HDL and LDL-CS, as well as protein, creatinine, lactate and plasminogen levels are determined. A urinalysis is also required.

Instrumental diagnostics are performed:

• ultrasound Doppler vascular imaging
• CT angiography
• magnetic resonance angiography

If symptoms of lower extremity angiopathy are present, lower extremity functional tests are required.

Differential diagnosis

Differential diagnosis is made with chronic venous insufficiency, arterial embolism, acute arterial thrombosis, aortic dissection, chronic tension syndrome (compartment syndrome).

Treatment of the arterial insufficiency

Depending on the localization and degree of arterial insufficiency, treatment can be conservative and surgical. Various drugs are used in drug therapy, including:

• angioprotectors and microcirculation correctors: Pentoxifylline, Agapurin, etc;
• antithrombotic agents (anticoagulants): Warfarin, Heparin and its derivatives;
• antiaggregants and antithrombotic agents: Plavix (Clopidogrel), Cilostazol, Indobufen, Aspirin, Ticlopidine or Ticlid;
• Fibrinolytics or thrombolytic drugs: Urokinase, Streptokinase, Alteplase, etc;
• drugs of the statin group for lowering cholesterol: Simvastatin, Lovastatin, Wabadin etc.

In cases of acute occlusion of peripheral arteries and critical ischemia of the lower extremities, emergency treatment of acute arterial insufficiency is required. First of all, heparin (at least 5000 units) is administered parenterally. Immediate angiography is also necessary to confirm the localization of occlusion and emergency therapy aimed at restoring blood flow - revascularization of the limb. This may include regional catheter thrombolysis (dissolution of the thrombus with fibrinolytic drugs within several hours), as well as removal of the thrombus from the artery (thrombectomy), removal of atheromatous plaques (endarterectomy), peripheral artery bypass (to create a bypass route for blood flow).

For severe limb ischemia at rest and severe progressive claudication - to minimize the likelihood of limb loss, reduce symptoms, and improve quality of life - surgical treatment by embolectomy, surgical thrombolysis, endovascular dilatation (angioplasty) or vascular bypass is necessary. [5]

To restore blood supply to the heart, coronary artery stenting is used. In the case of renal artery stenosis, possible surgical interventions include aorto-renal and hepatorenal bypass surgery and transaortic endarterectomy.

Physiotherapeutic treatment involves physiotherapy for trophic ulcers on the extremities, as well as therapeutic massage to activate blood circulation

Significantly reduces the intensity of intermittent claudication therapeutic exercise in arterial insufficiency of the lower limbs, as well as daily walking (at least an hour a day).

Is herbal treatment possible in this vascular pathology? Phytotherapy can not restore normal blood flow, but to reduce cholesterol, decoctions and infusions of leaves of nettle dicot, white laurel, buddleia ivy; for heart pain - heartwort and marsh wheatgrass; for flatulence - fennel seeds, for diarrhea - erect lupus, yatryschnia or yarrow.

Prevention

Prevention of arterial insufficiency is prevention of atherosclerosis, including avoidance of bad habits (primarily smoking), proper nutrition and - as a must - moderate physical activity.

Forecast

In cases of chronic arterial insufficiency of the extremities, an unfavorable prognosis portends increased pain when walking and the resulting fear of movement, which not only worsens the physical condition of patients (leading to muscle atrophy), but also accelerates the progression of atherosclerosis.

Clinical experience confirms the need for amputation for acute lower extremity arterial insufficiency at 20% and mortality at 25%.