High blood pressure is a very common problem. Especially among the elderly and middle-aged people. There can be many reasons for hypertension. Among them are heart disease, kidney disease, endocrine disorders. As you know, high blood pressure can lead to stroke and heart attack. To understand how to deal with this symptom, it is necessary to establish the cause. In some cases, hypertension occurs against the background of a pathology such as renal artery stenosis. Treatment of this disease should be started as early as possible. After all, arterial stenosis can lead not only to an increase in blood pressure, but also to other serious consequences. Pathology occurs in both men and women. In some cases, the disease is congenital. More often it occurs against the background of vascular disorders.
Read more about renal artery stenosis
Stenosis of the renal artery is a narrowing of the lumen of the vessel due to various pathological conditions. The disease is classified as a nephropathic pathology. Renal arteries are large vessels that supply blood to tissueorgan. With stenosis, they noticeably decrease in diameter. As a result, the process of blood supply to the kidneys is disrupted. This pathology leads to such serious disorders as secondary arterial hypertension, CRF. There are 2 mechanisms for the development of stenosis. Among them:
- Atherosclerotic variant. It is observed in most of the patients suffering from this pathology. A similar mechanism for the development of stenosis consists in the gradual blockage of the lumen of the vessel by cholesterol plaques. Severe vascular occlusion is often noted in the elderly.
- Fibromuscular dysplasia. This variant of the development of pathology is less common. It can occur in middle-aged women and also among young girls. Muscle dysplasia is a hereditary birth defect.
Only after an instrumental examination can a diagnosis of "renal artery stenosis" be established. ICD is a classification of pathologies used throughout the world. It includes many diseases, each of which has a specific code. Renal artery stenosis is encoded in 2 ways, depending on the cause of its occurrence. One option is code I15.0, which means "renovascular hypertension." Another ICD code is Q27.1. It stands for "congenital renal artery stenosis". Both conditions require treatment by a urologist or vascular surgeon.
Renal artery stenosis: causes of pathology
Narrowing of the lumen of the peripheral arteries is referred to as a pathology of the vascular system. Allocatevarious causes of stenosis. The most common of these is atherosclerosis. As you know, in most cases it is observed in people who are overweight, leading a sedentary lifestyle or suffering from diabetes. Atherosclerosis can develop over a long period of time. However, it is rarely diagnosed before symptoms of clogged arteries appear. Other causes of stenosis include:
- Fibromuscular dysplasia. This term refers to a congenital genetic defect, which results in a lack of muscle fibers in the wall of blood vessels. Pathology is observed in women of any age.
- Aneurysm of the arteries of the kidneys.
- Tumours of peripheral vessels.
- Congenital and acquired vasculitis.
- Compression of the renal artery by neoplasms originating from the tissues of neighboring organs.
The listed reasons are rare. Therefore, their diagnosis is started only after the exclusion of atherosclerosis.
Mechanism of development of hypertension
The main symptom of renal artery stenosis is an increase in blood pressure. Therefore, with this clinical syndrome, an examination of the renal system is necessary. How are renal artery stenosis and arterial hypertension related? 2 mechanisms are involved in the increase in blood pressure:
- Activation of the renin-angiotensin system. Under the influence of these biological substances, narrowing of the arterioles develops. As a result, peripheral vascular resistance increases. Thus, bloodthe pressure in the arteries rises.
- Aldosterone action. This hormone is produced in the adrenal cortex. Normally, it is constantly present in the body. However, with arterial stenosis, its production is enhanced. Due to excess aldosterone, fluid and sodium ions accumulate in the body. This, in turn, also causes an increase in blood pressure.
As a result of chronic hypertension, changes occur in the cardiovascular system. The left ventricle gradually hypertrophies and stretches. This is another cause of hypertension.
Renal artery stenosis: symptoms of the disease
Narrowing of the arteries of the kidneys has many consequences. Symptoms of stenosis do not appear immediately, but only with severe occlusion. However, conservative treatment is not always effective. In addition to vascular disorders, arterial stenosis leads to ischemic changes in the kidney. As a result, the filtration and concentration function of the organ suffers. Given this, 2 clinical syndromes can be distinguished that develop with stenosis. The first is arterial hypertension. This syndrome is characterized by a number of clinical manifestations. Among them:
- Increased blood pressure. It can be either episodic or permanent. Of particular importance for diagnosis is an increase in diastolic blood pressure (more than 100 mm Hg).
- Appearance of tinnitus.
- Dizziness.
- Nausea that has nothing to do with eating.
- Flashing"flies" before the eyes.
- Headache in the temples, forehead.
- Irritable.
The second clinical syndrome is ischemic nephropathy. Due to impaired renal blood flow, the “nutrition” of the organ stops. Bilateral stenosis of the renal arteries is especially dangerous. Hypertension is a condition that can be partially controlled with medication. Unfortunately, severe organ ischemia cannot be corrected with drugs. The symptoms of "oxygen starvation" of the kidney should include: pain in the lumbar region, changes in urination. Often there is a decrease in the amount of fluid released, general weakness. An admixture of blood, a cloudy sediment may appear in the urine.
Diagnosis
Only after examination can a diagnosis of "renal artery stenosis" be made. Diagnosis of pathology includes the collection of complaints and anamnesis of the disease, laboratory tests and instrumental methods. Most often, the leading syndrome is arterial hypertension, which is poorly amenable to antihypertensive therapy. Also, patients may complain of discomfort in the lower back (on one or both sides), a change in the nature of urination. The examination plan includes:
- CBC and urinalysis.
- ECG.
- Biochemical blood test. The disease can be suspected with an increase in the level of creatinine and urea.
- Ultrasound of the kidneys.
- Special samples: urinalysis according to Nechiporenko, Zimnitsky.
- X-ray contrast study of blood vessels –renography.
- Dopplerography of the renal arteries.
- Angiography.
- CT and MRI.
Differential Diagnosis
Given that the hypertensive syndrome is the leading one, renal artery stenosis is differentiated from heart pathologies, aortic atherosclerosis. Also, the symptoms may resemble Cushing's disease and pheochromocytoma.
If signs of ischemic nephropathy prevail, then stenosis is differentiated from inflammatory pathologies of the kidneys. These include pyelo- and glomerulonephritis. Also, similar symptoms can be observed with a complication of diabetes.
Conservative therapy for renal artery stenosis
Treatment of renal artery stenosis begins with conservative methods. With hypertension caused by narrowing of the renal vessels, a combination of several drugs is necessary. Angiotensin-converting enzyme inhibitors are preferred. But these drugs are not recommended for severe atherosclerotic vascular lesions. The combination is made up of the following groups of medicines:
- Beta blockers. These include drugs Metoprolol, Coronal, Bisoprolol.
- Loop diuretics. The drug of choice is the medicinal substance Furosemide.
- Calcium channel blockers. Among them are the medicines "Verapamil", "Diltiazem".
In addition, the patient must take the drugs necessary to treat the underlying disease (atherosclerosis, diabetes mellitus).
Surgical treatment of stenosis
Unfortunately, in most cases, antihypertensive therapy is ineffective. In addition, lowering blood pressure only exacerbates ischemic nephropathy. Therefore, it is necessary to resort to surgical intervention. Depending on the degree of damage, choose the method of surgical treatment. Most often, stenting of the artery supplying the kidney is performed. If the entire lumen of the vessel is obturated over a long distance, shunting is performed - replacing a section of the vessel with a graft. When the kidney tissue dies, a nephrectomy is performed.
Prognosis after surgical treatment of stenosis
Regardless of which side the lesion was (stenosis of the left renal artery or right), the prognosis after surgery depends on compliance with the doctor's recommendations and the patient's somatic condition. Often, surgical treatment can achieve a positive result. After a few months, 60-70% of patients normalize blood pressure.
Complications of renal stenosis
Unfortunately, renal artery stenosis is diagnosed only at a late stage of development. Therefore, it is impossible to neglect the recommendations of the doctor. After all, without proper treatment, terrible complications can develop. Among them are myocardial infarction and stroke against the background of a hypertensive crisis, acute and chronic renal failure. If surgery is not performed in time, the patient may lose the organ.
Prevention
Preventive measures include continuous monitoring of blood pressure in the presence of complaints ofdizziness and tinnitus, quitting smoking and alcoholic beverages. To avoid the progression of atherosclerosis, it is necessary to follow a special hypocholesterol diet, lead an active lifestyle. Some patients need to take special drugs called statins.
