Renovascular arterial hypertension

Renovascular arterial hypertension is a form of renal arterial hypertension associated with occlusion of the renal artery or its branches. The disease can be cured by restoring blood circulation in the kidneys.

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Epidemiology

The incidence of renovascular hypertension is 1% of all cases of arterial hypertension, 20% of all cases of resistant arterial hypertension, 30% of all cases of rapidly progressive or malignant arterial hypertension.

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Causes Renovascular arterial hypertension.

The main causes of renovascular arterial hypertension leading to narrowing of the lumen of the renal arteries are atherosclerosis of the main renal arteries and fibromuscular dysplasia. Rare causes of renovascular arterial hypertension include thrombosis of the renal arteries or their branches (complication of diagnostic and therapeutic interventions on the vessels, abdominal trauma, atrial fibrillation), nonspecific aortoarteritis (Takayasu's disease), nodular polyangiitis, aneurysm of the abdominal aorta, tumor, parapelvic cyst of the kidney, renal tuberculosis, anomalies of their structure and location leading to kinking or compression of their main arteries.

Renal artery stenosis of atherosclerotic genesis is the most common, approximately 2/3 of all cases. The disease usually develops in elderly and senile individuals (although it can also occur in younger people), more often in men. Risk factors are hyperlipidemia, diabetes mellitus, smoking, and the presence of widespread atherosclerosis (especially of the branches of the abdominal aorta - femoral and mesenteric arteries). However, atherosclerotic changes in the renal arteries may not correspond to the severity of atherosclerosis in other vessels, as well as the degree of increase in serum lipid levels. Atherosclerotic plaques are usually localized in the orifice or proximal third of the renal arteries, more often the left ones, in approximately 1/2-1/3 of cases the lesion is bilateral. The progression of atherosclerosis with the formation of bilateral hemodynamically significant stenosis, the development of cholesterol embolism lead to impaired renal function and their damage within the framework of ischemic kidney disease (the features of atherosclerotic lesions of the renal arteries and kidneys, the principles of diagnosis and treatment are described in detail in the article "Ischemic kidney disease").

Fibromuscular dysplasia of the renal arteries is the cause of renovascular hypertension in approximately 1/3 of patients. It is a non-inflammatory lesion of the vascular wall characterized by the transformation of smooth muscle cells of the media into fibroblasts with the simultaneous accumulation of bundles of elastic fibers at the border with the adventitia, leading to the formation of stenoses alternating with areas of aneurysmal dilations, as a result of which the artery acquires the appearance of beads. Fibromuscular dysplasia of the renal arteries is observed mainly in females. Renal artery stenosis caused by fibromuscular dysplasia is the cause of severe arterial hypertension in young people or children.

Recent angiographic studies of kidney donors and healthy individuals using ultrasound Doppler imaging have shown that the incidence of such stenosis in the general population is significantly higher than previously thought, about 7%, but in most cases there are no clinical manifestations or complications. Fibromuscular dysplasia of the renal arteries may be combined with lesions of other elastic arteries (carotid, cerebral). Studies of direct relatives of individuals suffering from fibromuscular dysplasia of the renal arteries show a familial predisposition to this disease. Among possible hereditary factors, the role of a mutation in the a1-antitrypsin gene, accompanied by a deficiency in its production, is discussed. Changes occur in the middle or, more often, the distal part of the renal artery; segmental arteries may be involved. The pathology develops more often on the right, in a quarter of cases the process is bilateral.

The main link in the pathogenesis of renovascular arterial hypertension is considered to be the activation of the renin-angiotensin-aldosterone system in response to a decrease in blood supply to the kidney on the affected side. Goldblatt was the first to prove this mechanism in an experimental setting in 1934, and then it was repeatedly confirmed by clinical studies. As a result of renal artery stenosis, the pressure in it distal to the site of narrowing decreases, kidney perfusion worsens, which stimulates renal secretion of renin and the formation of angiotensin II, which leads to an increase in systemic arterial pressure. Inhibition of renin secretion in response to an increase in systemic arterial pressure (feedback mechanism) does not occur due to narrowing of the renal artery, which leads to a persistent increase in the renin level in the ischemic kidney and the maintenance of high arterial pressure values.

In unilateral stenosis, in response to an increase in systemic arterial pressure, the unaffected contralateral kidney intensively excretes sodium. At the same time, the contralateral kidney's mechanisms of renal blood flow self-regulation aimed at preventing its damage in systemic arterial hypertension are disrupted. At this stage, drugs that block the renin-angiotensin system cause a marked decrease in arterial pressure.

In the late phase of renovascular arterial hypertension, when pronounced sclerosis of the contralateral kidney develops due to its hypertensive damage and it can no longer excrete excess sodium and water, the mechanism of arterial hypertension development becomes no longer renin-dependent, but sodium-volume-dependent. The effect of the renin-angiotensin system blockade will be insignificant. Over time, the ischemic kidney becomes sclerotic, its function irreversibly decreases. The contralateral kidney also gradually becomes sclerotic and decreases in size due to hypertensive damage, which is accompanied by the development of chronic renal failure. However, the rate of its sclerosis is significantly lower with unilateral than with bilateral stenosis.

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Symptoms Renovascular arterial hypertension.

In fibromuscular dysplasia, increased blood pressure is detected in young or childhood. Atherosclerotic renal artery stenosis is characterized by de novo development or a sharp worsening of previous arterial hypertension in old or senile age. Renovascular arterial hypertension, as a rule, has a severe, malignant course with pronounced left ventricular myocardial hypertrophy and retinopathy, and is often refractory to multicomponent antihypertensive therapy. In elderly patients with bilateral renal artery stenosis, the symptoms of renovascular arterial hypertension include recurrent episodes of pulmonary edema due to decompensation of cardiac function against the background of severe volume-dependent arterial hypertension.

Changes in the kidneys are more often detected in atherosclerotic lesions. Early and progressive decrease in filtration function is noteworthy, while deviations in urine tests are expressed minimally: moderate or trace proteinuria is observed; as a rule, there are no changes in sediment (except for cases of cholesterol embolism and thrombosis of the renal vessels). A sharp increase in azotemia in response to the administration of ACE inhibitors or angiotensin receptor blockers allows us to suspect atherosclerotic stenosis of the renal arteries with a high probability.

In fibromuscular dysplasia, decreased renal function is absent or develops in the late stages of the disease. The presence of urinary syndrome is not typical; microalbuminuria or minimal proteinuria may be observed.

Diagnostics Renovascular arterial hypertension.

Based on the anamnesis data (age of disease development, indication of the presence of cardiovascular diseases and complications), examination and physical examination, as well as routine nephrological clinical and laboratory examination, one can suspect the renovascular nature of arterial hypertension.

During examination and physical examination, primary attention is paid to the symptoms of cardiovascular diseases. Atherosclerotic stenosis of the renal arteries is often combined with signs of impaired patency of the vessels of the lower extremities (intermittent claudication syndrome, pulse asymmetry, etc.). A diagnostically valuable, although not very sensitive symptom of renovascular hypertension is listening to noise over the abdominal aorta and in the projection of the renal arteries (noted in half of the patients).

To clarify and verify the diagnosis of renovascular arterial hypertension, special research methods are required.

Laboratory diagnostics of renovascular arterial hypertension

Urine examination reveals moderate or minimal proteinuria, although it is absent in the early stages of the disease. The most sensitive marker of kidney damage is microalbuminuria.

Increased blood creatinine levels and decreased glomerular filtration rate in the Reberg test are characteristic of bilateral atherosclerotic stenosis of the renal arteries. In fibromuscular dysplasia of the renal arteries, renal dysfunction is rare and corresponds to the late stage of the disease.

To clarify the risk factors for atherosclerotic renal artery stenosis, the lipid profile and blood glucose levels are examined.

Patients with renovascular arterial hypertension are characterized by an increase in plasma renin activity and the development of secondary hyperaldosteronism. Hypokalemia is often observed. However, in bilateral atherosclerotic stenosis of the renal arteries with impaired renal function, these changes may be absent. To increase the sensitivity and specificity of this laboratory test, a captopril test is used. It is carried out against the background of normal sodium intake; diuretics and ACE inhibitors are discontinued several days before. The test is carried out with the patient sitting, after a 30-minute adaptation period, blood is taken twice: before oral administration of 50 mg of captopril and 1 hour after it. The test is considered positive if the plasma renin activity after taking captopril is higher than 12 ng / ml / h or its absolute increase is at least 10 ng / ml / h.

The most accurate method is to measure plasma renin activity obtained by catheterization of the renal vein and compare it with the renin activity in the systemic circulation (in blood obtained from the inferior vena cava to the point where the renal veins enter). However, due to the risk of complications associated with the invasive nature of the test, it is considered justified only in the most severe and complex cases when surgical treatment is being considered.

The main role in the diagnosis of renovascular arterial hypertension is played not by laboratory, but by radiation diagnostics of renovascular arterial hypertension.

Ultrasound examination (US) allows to detect asymmetry of kidney size, signs of cicatricial changes in patients with atherosclerosis, calcification and atherosclerotic deformation of the vascular wall. However, the diagnostic value of conventional ultrasound is low.

The main screening methods used are ultrasound Dopplerography (USDG) of the renal arteries and dynamic renal scintigraphy.

Ultrasound Dopplerography is a non-invasive, safe examination that can be performed even in cases of severe renal failure. In the energy Doppler mode, the method, like angiography, allows visualizing the arterial tree of the kidney - from the renal artery to the level of the arcuate, and with high resolution of the device - to the interlobular arteries, identifying additional renal vessels, visually assessing the intensity of renal blood flow, detecting signs of local ischemia in patients with volumetric kidney lesions and destructive lesions. Spectral Dopplerography is used for quantitative assessment of the linear velocity of blood flow in different phases of the cardiac cycle.

A highly sensitive and specific sign of renal artery stenosis > 60% is a local sharp increase in blood flow velocity, mainly during systole. In this case, the amplitude of the spectrogram waves increases and they become pointed. The systolic linear blood flow velocity at the site of stenosis reaches a level of > 180 cm / s or 2.5 standard deviations above the norm; the renal-aortic index (the ratio of systolic linear blood flow velocity in the renal artery and aorta) increases to > 3.5. With a combination of these symptoms, the sensitivity of the method exceeds 95%, and the specificity is 90%. At the same time, overdiagnosis is possible, since high blood flow velocity is observed not only in atherosclerotic stenosis, but also in some anomalies in the structure of the renal vessels, in particular, the scattered type of renal artery structure, the presence of additional thin-diameter arteries originating from the aorta, at the site of the artery bend.

Distal to the stenosis site, the opposite picture is observed: intrarenal blood flow is sharply depleted, only segmental and sometimes interlobar arteries are visualized, the blood flow velocity in them is slowed, the systolic-diastolic ratio is reduced, and the acceleration time is increased. On spectrograms, the waves look gentle and flattened, which is described as the phenomenon of pulsus parvus et tardus. However, these changes are significantly less specific than an increase in the systolic linear blood flow velocity at the site of stenosis, and can be observed in edema of the renal parenchyma in patients with acute nephritic syndrome, hypertensive nephroangiosclerosis, thrombotic microangiopathy, renal failure of any etiology, and other conditions.

To increase the sensitivity and specificity of the method, a pharmacological test with 25-50 mg of captopril is used, which allows identifying the appearance or worsening of pulsus parvus et tardus 1 hour after administration of the drug.

The absence of visualization of renal blood flow in combination with a decrease in the length of the kidney to <9 cm indicates complete occlusion of the renal artery.

Disadvantages of USDG are high labor intensity and duration of the examination, the need for high training and extensive experience of the specialist, the impossibility of examining the renal arteries along their entire length, low information content in obese patients and with significant intestinal obstructions. New modifications of USDG, significantly expanding its capabilities, are the use of intra-arterial sensors and gas contrast.

Dynamic scintigraphy allows visualization and quantitative assessment of the entry and accumulation of radiopharmaceutical drug (RPD) in the kidneys, which reflects the state of blood flow and activation of the intrarenal renin-angiotensin system. When using RPDs excreted only by filtration (diethylenetriamine pentaacetic acid labeled with technetium-99m - ^99m Tc-DTPA), it is possible to separately assess the glomerular filtration rate in each kidney. Radiopharmaceuticals secreted by tubules - technetium-99m-labeled mercaptoacetyltriglycine (Tc -MAG ³₎, dimercaptosuccinic acid ( ^99m Tc-DMSA) - allow obtaining a contrast image showing the distribution of blood flow in the kidneys and identifying its heterogeneity: local ischemia during occlusion of a segmental artery, the presence of collateral blood flow, for example, blood supply to the upper pole of the kidney due to an additional artery.

Characteristic signs of renal artery stenosis are a sharp decrease in the flow of radiopharmaceuticals into the kidney and a slowdown in its accumulation. The renogram (a curve depicting changes in radiological activity in the projection of the kidney) changes its shape: it becomes more flattened, while the vascular and secretory segments become more gentle; as a result, the time of maximum activity (Tmax ₎ increases significantly.

When using radiopharmaceuticals excreted only by glomerular filtration ( ^99m Tc-DTPA), the slowing down of the early accumulation phase (from 2 to 4 min) is of diagnostic value. In case of moderate renal impairment (blood creatinine level 1.8-3.0 mg/dl), great caution is required when using ^99m Tc-DTPA; it is preferable to use radiopharmaceuticals secreted by the tubules ( ^99m Tc-MAG ₃ ). The slowing down of the secretory phase is of diagnostic value, which reflects increased reabsorption of sodium and water due to a decrease in hydrostatic pressure in the interstitium under the influence of angiotensin II, which causes stenosis of the efferent arteriole. To increase the sensitivity and specificity of the method, a pharmacological test with captopril is used: 25-50 mg of captopril is prescribed 1 hour after the first study, the radiopharmaceutical is administered again after 30 minutes and scintigraphy is repeated.

In the absence of stenosis, no changes in renograms are observed after the administration of captopril. In case of renal artery stenosis, a sharp drop in the glomerular filtration rate and an increase in the duration of the phases of rapid and slow accumulation of the radiopharmaceutical in the kidney are observed. It is important to emphasize that a positive test with captopril is not a direct indication of the presence of stenosis, but reflects the activation of the intrarenal renin-angiotensin system. It can be positive in the absence of significant stenosis in patients with hypovolemia, with regular intake of diuretics (the latter should be excluded at least 2 days before the test), with a sharp drop in blood pressure in response to the administration of captopril. In case of significant chronic renal failure (creatinine level in the blood from 2.5 to 3.0 mg / dl), the use of the captopril test is inappropriate. Severe chronic renal failure (creatinine level in the blood more than 3 mg/dl), in which the excretion of radiopharmaceuticals is sharply slowed, is a contraindication for radioisotope research.

To verify the diagnosis of renal artery stenosis, accurately determine its location, degree and decide on the advisability of surgical treatment, determine its tactics, X-ray examination methods and magnetic resonance imaging in the angiography mode (MRI angiography) are used. Given their complexity, high cost and risk of complications, some authors consider it justified to use these methods only in those patients who have no contraindications to surgical treatment.

The "gold standard" for diagnosing renal artery stenosis remains angiography with intra-arterial contrast administration - standard or digital subtraction, which eliminates interference and provides high image contrast. This method allows for the highest resolution visualization of the renal arterial tree, identification of collateral blood flow, study of the structural features of the stenotic section of the artery, and measurement of the blood pressure gradient before and after stenosis, i.e. it makes it possible to assess the degree of stenosis not only anatomically but also functionally. A significant drawback of angiography is the risk of complications associated with catheterization of the abdominal aorta and renal artery, including vessel perforation, destruction of unstable atherosclerotic plaques, and cholesterol embolism of distally located renal vessels. Intravenous digital subtraction angiography of the kidneys, unlike intra-arterial, is the safest in terms of invasiveness, but requires the administration of high doses of contrast and is characterized by significantly lower resolution.

Spiral computed tomography (CT) of the renal vessels with intravenous or intra-arterial administration of contrast makes it possible to obtain a three-dimensional image of the renal arterial system with good resolution. Multispiral tomographs allow not only to study the structure of the arterial tree and the anatomical features of the stenosis site, but also to assess the nature and intensity of blood flow. It requires the introduction of a large dose of radiocontrast agent, which limits the use of the method in severe chronic renal failure. In order to reduce the risk of acute renal failure, carbon dioxide can be used as a contrast agent. Compared with conventional angiography, CT angiography more often gives false-positive results.

Magnetic resonance imaging (MRI) can be used in patients with severe renal dysfunction, since the gadolinium contrast used in this method of examination is the least toxic. MRI has a lower resolution than X-ray contrast spiral computed tomography and, like it, gives more false-positive results compared to conventional angiography. With the help of modern magnetic resonance tomographs with a mobile table, a one-time comprehensive study of all the main vessels of the body is possible to clarify the extent of the lesion.

As additional instrumental methods, examination of the patient should include echocardiography, examination of the vessels of the fundus to assess the degree of damage to target organs; it can be supplemented by ultrasound Doppler imaging or angiography of other vascular pools (arteries of the lower extremities, neck, etc.).

Differential diagnosis

Renovascular arterial hypertension is differentiated from other types of secondary renal arterial hypertension (within the framework of parenchymatous kidney diseases, chronic renal failure) and essential arterial hypertension. Differential diagnostics of fibromuscular dysplasia and atherosclerotic stenosis of the renal arteries, as a rule, is not difficult. However, it is necessary to take into account that secondary early atherosclerotic stenosis may develop against the background of previous latent fibromuscular dysplasia. Diagnostics and differential diagnostics of rare causes of renovascular arterial hypertension (vasculitis, destructive kidney lesions, space-occupying lesions causing compression of the renal vessels) are also based primarily on the data of radiation examination methods.

In patients with newly diagnosed, presumably, renal arterial hypertension, it is also necessary to exclude antiphospholipid syndrome (APS), which can cause an increase in blood pressure due to ischemic damage to the kidneys at the level of the microcirculatory bed, and lead to the development of stenosis or thrombosis of the renal artery. The presence of a history of recurrent arterial or venous thrombosis, habitual miscarriage, detection of an increased titer of antibodies to cardiolipin and lupus anticoagulant in the anamnesis indicate antiphospholipid syndrome.

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Treatment Renovascular arterial hypertension.

Treatment of renovascular arterial hypertension is aimed at normalizing blood pressure, reducing the risk of cardiovascular complications and preventing renal failure. In the case of atherosclerotic stenosis of the renal arteries, leading to the development of ischemic kidney disease (see the corresponding chapter), the task of nephroprotection comes to the forefront.

Conservative treatment of renovascular arterial hypertension

In renovascular hypertension, as well as in essential arterial hypertension, diet is of great importance, ensuring the limitation of consumption of table salt to a level of <3 g/day, as well as correction of lipid, purine and carbohydrate metabolism disorders, smoking cessation and other non-drug treatment of renovascular arterial hypertension, reducing the risk of cardiovascular diseases.

Among antihypertensive drugs in the treatment of patients with renovascular arterial hypertension, ACE inhibitors and angiotensin receptor blockers, acting on the main link of its pathogenesis, occupy a special place. In fibromuscular dysplasia, especially in the early stages of arterial hypertension, they have a clear therapeutic effect in more than 80% of cases. In the later stages, their effectiveness is lower. In moderate unilateral atherosclerotic stenosis of the renal artery, their use is also justified due to their antiatherogenic and cardioprotective properties.

At the same time, in hemodynamically significant bilateral renal artery stenosis, drugs blocking the renin-angiotensin system can cause a sharp destabilization of renal hemodynamics (weakening and slowing of blood flow, a drop in pressure in the glomerular capillaries) with the development of acute renal failure and are therefore absolutely contraindicated. Particular caution is required in patients with atherosclerotic stenosis, which is characterized by a rapid increase in the degree of narrowing and further addition of stenosis of the artery of the contralateral kidney.

A mandatory condition for the safety of therapy with ACE inhibitors and angiotensin receptor blockers is monitoring the level of creatinine and potassium in the blood before and during treatment (at least once every 6-12 months, during the selection of therapy - at least once a month).

Slow calcium channel blockers of the dihydropyridine series also have a pronounced antihypertensive effect, do not aggravate metabolic disorders and can slow down the process of plaque formation and growth. They have no limitations in the treatment of patients with renovascular arterial hypertension and can be used as first-line drugs.

In most cases, monotherapy is ineffective and requires additional administration of antihypertensive drugs of other classes: beta-blockers, diuretics, alpha-blockers, imidazoline receptor agonists. In severe renovascular arterial hypertension, treatment with 4-5 drugs of different classes in maximum or submaximal therapeutic doses may be required.

In case of atherosclerotic stenosis of the renal arteries, the administration of antihyperlipidemic drugs is indicated - statins as monotherapy or in combination with ezetimibe (see "Ischemic kidney disease").

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Surgical treatment of renovascular arterial hypertension

Surgical treatment of renovascular arterial hypertension is indicated when conservative methods are insufficiently effective. Arguments in favor of surgical treatment methods include a high risk of side effects, adverse drug interactions, and high material costs associated with multicomponent antihypertensive therapy. Technical success of surgical intervention (restoration of vessel patency or formation of adequate collateral blood flow) does not always mean achievement of positive clinical results.

The main methods of surgical treatment of renal artery stenosis are percutaneous balloon angioplasty and open surgery.

Percutaneous balloon angioplasty is the "straightening" of a stenotic section of a vessel using a catheter equipped with a special balloon. Large peripheral arteries, usually femoral, are used for access. The undoubted advantage of this method compared to open surgery is the smaller volume of intervention and the lack of need for anesthesia. At the same time, one cannot ignore the possibility of developing dangerous complications (vascular rupture, massive bleeding, destruction of an unstable plaque with the development of cholesterol embolism of distally located vessels), although their risk, according to large vascular surgery centers, is low.

Localization of stenosis in the area of the renal artery orifice and complete occlusion of its lumen are contraindications for percutaneous angioplasty. The main problem with using this method is the high risk of restenosis (30-40% during the first year after the intervention), especially in patients with atherosclerosis. The introduction of stenting has made it possible to reduce the risk of restenosis by more than 2 times, practically reaching the indicators characteristic of open surgery.

Open angioplasty is the removal of an atherosclerotic plaque together with the affected area of the arterial intima or the entire stenotic area of the artery with subsequent reconstruction using the patient's own vessels (large veins, etc.) or prostheses made of biocompatible materials. Bypass surgery is used less often. The advantage of open surgery is the possibility of the most complete reconstruction of the vessel, elimination of blood flow turbulence, removal of atheromatous masses and affected intima, which support inflammation and contribute to the development of restenosis. Open surgery allows for complex treatment with prosthetics of several large branches of the abdominal aorta (celiac trunk, mesenteric, iliac arteries) in case of widespread atherosclerosis. At the same time, the disadvantage of open surgery is the high risk of cardiovascular complications in elderly patients associated with anesthesia, blood loss, hypovolemia and other factors.

Surgical treatment of renovascular hypertension depends on the nature of the stenosis, its characteristics and the general condition of the patient.

In young patients with fibromuscular dysplasia of the renal arteries, angioplasty allows for a radical effect on the cause of arterial hypertension and achieves complete normalization of arterial pressure and the abolition of antihypertensive drugs as unnecessary. A complete or partial (reduction in arterial pressure and the volume of necessary antihypertensive therapy) effect is observed in 80-95% of patients. The method of choice is percutaneous balloon angioplasty with stenting. The effect of treatment is usually persistent.

In elderly patients with atherosclerotic renal artery stenosis, the effectiveness of surgical treatment for arterial hypertension is significantly lower - 10-15%, and the risk of complications is higher than in young patients with fibromuscular dysplasia. The least favorable results are noted in patients with long-standing arterial hypertension, diabetes mellitus, widespread atherosclerosis, including cerebral vessels.

In the development of ischemic kidney disease, surgical treatment is carried out primarily not for the purpose of correcting arterial hypertension, but to preserve renal function. Stabilization or improvement of function can be achieved in more than ^3/4 of patients. However, with small kidneys, long-term, persistent decrease in filtration function, long-term history of arterial hypertension, surgical treatment is _ineffective and does not prevent the progression of chronic renal failure. High resistance indices according to ultrasound Doppler imaging of the vessels of the contralateral kidney are an unfavorable prognostic sign both in relation to a decrease in pressure in response to surgical treatment and in terms of renal function.

In most cases, percutaneous balloon angioplasty with stenting is recommended as the method of choice for atherosclerotic stenosis; in case of stenosis in the area of the ostium, complete occlusion or ineffectiveness of the previously performed percutaneous intervention - open angioplasty.

Nephrectomy is currently performed extremely rarely for the treatment of severe resistant renovascular hypertension - in cases where kidney function is completely impaired, according to radioisotope studies, and the renin activity of the blood plasma obtained during catheterization of its vein is significantly higher than in the systemic bloodstream.

Forecast

The prognosis for patients with renovascular arterial hypertension is unfavorable in its natural course due to the very high risk of cardiovascular complications. Modern drug therapy and surgical treatment of renovascular arterial hypertension can radically affect the course of the disease, but success depends on early diagnosis and timely medical interventions.

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