Atherosclerotic Stenosis of the Renal Artery

Atherosclerotic stenosis of the renal arteries (ischemic kidney disease, atherosclerotic renovascular hypertension) is a chronic kidney disease that manifests itself as signs of global renal hypoperfusion: a decrease in GFR, arterial hypertension, and an increase in nephrosclerosis due to hemodynamically significant narrowing of the main renal arteries by atherosclerotic plaques.

[1],

Epidemiology

The exact prevalence of atherosclerotic stenosis of the renal arteries has not been established, since many cases of it remain unrecognized during life and are not registered at autopsy due to the fact that cardiovascular complications are the immediate cause of death of these patients. In the registers of patients with ischemic kidney disease, including terminal, atherosclerotic stenosis of the renal arteries is often not taken into account, since it often erroneously diagnoses hypertensive nephroangiosclerosis, a latent version of chronic glomerulonephritis and other chronic nephropathies, with which further irreversible impairment of renal function is associated.

Nevertheless, it is now possible to assert that atherosclerotic stenosis of the renal arteries is one of the main causes of terminal renal failure in the elderly. Atherosclerotic stenosis of the renal arteries is the cause of not less than 15% of all cases of irreversible impairment of kidney function, recorded in the registers as their hypertensive lesion.

Atherosclerotic stenosis of the renal arteries is especially often found in patients with advanced and complicated atherosclerosis. Ischemic kidney disease is detected in almost 10% of patients who are simultaneously performing coronary angiography and abdominal aortography, and more than 15% of people dying from acute cerebrovascular accident.

The prevalence of atherosclerotic stenosis of the renal arteries is especially great in patients with long-term type 2 diabetes mellitus. Experience in the analysis of autopsies performed in this category of patients suggests that the frequency of atherosclerotic stenosis of the renal arteries in them can reach 20-25%.

Of particular interest is the study of the epidemiology of atherosclerotic stenosis of renal arteries in people who go to medical institutions due to a persistent increase in blood pressure. It has been established that atherosclerotic stenosis of the renal arteries accounts for not less than 15% of all cases of hypertension, including initially regarded as an essential, non-treatable combination of representatives of 2 classes of antihypertensive drugs.

[2], [3], [4], [5], [6], [7], [8]

Causes of the atherosclerotic stenosis of the renal artery

The cause of atherosclerotic stenosis of the renal arteries is described by the concept of risk factors that is generally accepted for other clinical variants of atherosclerosis. It is generally believed that atherosclerotic stenosis of the renal arteries is formed by the combination of several cardiovascular risk factors and their severity - "aggression".

As the main non-modifiable risk factor for atherosclerotic stenosis of the renal arteries, an elderly age is considered in which the probability of stenosing atherosclerotic lesions of the visceral aorta branches, including the renal arteries, increases manifold.

[9]

Symptoms of the atherosclerotic stenosis of the renal artery

Symptoms of stenosis of the renal arteries are not sufficiently specific; At the same time, in the detection of a combination of symptoms, further examination, especially the use of imaging techniques, is necessary to confirm atherosclerotic stenosis of the renal arteries.

Arterial hypertension is a mandatory symptom of atherosclerotic stenosis of the renal arteries. The features of arterial hypertension, typical of atherosclerotic stenosis of the renal arteries, include:

• the emergence of de novo in old age;
• loss of control over arterial pressure, previously decreased with the use of standard antihypertensive therapy regimens;
• refractory to combined antihypertensive therapy;
• III degree (European Society of Hypertension, 2003; All-Russian Scientific Society of Cardiologists, 2005) of arterial hypertension;
• primary increase in systolic blood pressure.

[10], [11], [12]

Forms

There is no generally accepted classification of atherosclerotic stenosis of the renal arteries. Localization is distinguished by:

• bilateral atherosclerotic stenosis of the renal arteries;
• predominantly one-sided atherosclerotic stenosis of the renal arteries;
• Atherosclerotic stenosis of the artery of a single functioning kidney;
• atherosclerotic stenosis of the arteries of the kidney graft.

In addition, we should separately consider ischemic kidney disease, accompanied by occlusion of the renal artery.

The degree of reduction in GFR is described by the classification of chronic kidney disease (NKF-DOQI, Chronic Kidney Disease).

Arterial hypertension in atherosclerotic stenosis of the renal arteries is characterized by reference to the generally accepted classification of the European Society of Hypertension (2003) and the All-Russian Scientific Society of Cardiology (2005) (see Renal Hypertension ).

[13], [14], [15], [16], [17], [18], [19]

Diagnostics of the atherosclerotic stenosis of the renal artery

Aimed atherosclerotic stenosis of the renal arteries justifies the above-mentioned features of arterial hypertension,  chronic renal failure, and also the detection of signs of widespread atherosclerosis. In physical examination, peripheral edema, manifestations of chronic heart failure (hepatomegaly, bilateral crepitus or wet wheezing in the basal parts of the lungs), as well as noise over the aorta and large vessels, including kidneys, can be detected. The sensitivity and specificity of these symptoms is extremely low.

Changes in urine in atherosclerotic stenosis of renal arteries are limited to "trace" proteinuria, often transient; hematuria, leukocyturia are not characteristic (with the exception of embolism of the intrarenal arteries and arterioles with cholesterol crystals).

[20], [21], [22]

Treatment of the atherosclerotic stenosis of the renal artery

General principles of treatment of ischemic disease:

• minimization of the number of medicines used (if possible, elimination of NSAIDs, antibacterial and antifungal drugs);
• administration of statins (possibly in combination with ezetimibe);
• abolition of ACE inhibitors and angiotensin II receptor blockers;
• optimization of diuretic use (prevention of forced diuresis);
• if possible, early use of invasive treatments.

Forecast

Atherosclerotic stenosis of the renal arteries is a steadily progressing disease. Many patients, at the same time, do not survive to terminal renal failure, dying from cardiovascular complications. The lifespan of patients with atherosclerotic renovascular hypertension, who are on program hemodialysis, is significantly lower in comparison with those suffering from other chronic kidney diseases; Cardiovascular complications are also among the causes of death. The prognosis for cholesterol embolism of the intrarenal arteries and arterioles is usually unfavorable.

[23], [24], [25]