Diabetes mellitus and heart diseases

Diabetes mellitus is recognized by World Health Organisation experts as a non-communicable epidemic and represents a serious medical and social problem. In 2012, suffered of diabetes mellitus about 6.4% (285 million) of the world’s inhabitants. By 2030, the number of patients is expected to increase to 7.7% (439 million people) [1]. Coronary heart disease is the leading cause of death in patients with diabetes [2], with 90% of these patients suffering from type 2 diabetes (diabetes mellitus 2) [3].


Introduction
Diabetes mellitus is recognized by World Health Organisation experts as a non-communicable epidemic and represents a serious medical and social problem. In 2012, suffered of diabetes mellitus about 6.4% (285 million) of the world's inhabitants. By 2030, the number of patients is expected to increase to 7.7% (439 million people) [1]. Coronary heart disease is the leading cause of death in patients with diabetes [2], with 90% of these patients suffering from type 2 diabetes (diabetes mellitus 2) [3].
The presence of diabetes is associated with the emergence of all forms of coronary heart disease -angina pectoris, painless myocardial ischemia, myocardial infarction, sudden cardiac death [4]. At the same time, macrovascular complications, including coronary heart disease, stroke, peripheral vascular disease, are the cause of death of patients with diabetes in 67% of cases [5]. In 50% of cases, the increased risk of developing cardiovascular lesions in diabetes mellitus 2 is due to the greater frequency and severity of traditional risk factors in diabetic patients [6,7]. Risk factors in patients with diabetes are: dyslipidemia, arterial hypertension, smoking, hereditary predisposition for coronary heart disease, the presence of micro-and macroalbuminuria.

Diabetes mellitus and lipid metabolism disorders
A study of the prevalence, methods of diagnosis and treatment of dyslipidemia is of particular interest in patients with diabetes. Information on the prevalence of dyslipidemia in patients with diabetes 2 is presented in table 1 [8,9].
It should be especially noted hypertriglyceridemia and a decrease in the level of high-density lipoprotein cholesterol [10,11]. In patients with diabetes mellitus 2, hyperproduction of "small, dense" low-density lipoproteins is isolated [12]. At the same time, 69% of patients with diabetes have lipid metabolism disorders [13]. The atherogenic effect of dyslipidemia is enhanced by the addition of diabetic disturbances in carbohydrate metabolism. For patients suffering from diabetes, the most typical lipid triad with diabetes: hypertriglyceridemia, an increase in the percentage of "small, dense" low-density lipoproteins, a decrease in high-density lipoprotein cholesterol.
These changes in the lipid spectrum contribute to the development of atherosclerosis, regardless of the increase in the level of total cholesterol and the total fraction of low-density lipoproteins cholesterol.
Considering the important role of triglycerides in the development of dyslipidemia in diabetes mellitus, we cite the classifi cation of serum triglycerides levels (

Diabetes mellitus, ischemic heart disease and hypertension
Epidemiological data suggest a reliable relationship between the level of glycosylated hemoglobin and the risk of cardiovascular morbidity and mortality. With an increase in the level of glycosylated hemoglobin by 1%, the risk of cardiovascular morbidity increases by 10% [15].  Insulin resistance also plays a critical role in the pathogenesis of diabetes 2. Hyperinsulinemia is closely related to the metabolic syndrome, which includes insulin resistance, arterial hypertension and obesity and is accompanied by a high risk of coronary heart disease.
The change in the concentration of plasma lipids in diabetes mellitus 2 is a predictor of coronary heart disease. It was established that in persons with high blood glucose level in the blood on an empty stomach and after a load signifi cantly higher cardiovascular morbidity mortality was noted [16].
Asymptomatic hyperglycemia, especially in women, is an important risk factor for the development of coronary heart disease [17].
The effect of hyperinsulinemia and insulin resistance on the development of atherosclerosis is associated with the impact on blood coagulation processes [18]. Hypercoagulation and depression of fi brinolysis are noted, which can contribute to intracoronary thrombosis. In patients with diabetes mellitus 2, damage to the endothelium and its dysfunction are detected, which is an additional factor in the increased risk of developing coronary artery disease.
The main cause of death of patients with diabetes is the coronary heart disease, up to 80%. Mortality from myocardial infarction among patients with diabetes is 39% [19], from stroke -exceeds that in people without diabetes [5]. With the combination of arterial hypertension and diabetes in 2-4 times the risk of developing coronary artery disease, which directly correlates with the duration of diabetes [20]. Arterial hypertension is found in 20-60% of patients with diabetes mellitus 2, it occurs 1.5 times more often than in people without diabetes. The presence of arterial hypertension in diabetes increases the risk of macrovascular (coronary heart disease, cardiac failure, and stroke) and microvascular (diabetic retinopathy, nephropathy) complications [21]. Important is the fact that in patients with AH and diabetes the benefi ts of antihypertensive therapy are more pronounced than in patients without diabetes. In this regard, strict control of blood pressure in this group of patients is extremely necessary.
With diabetes the emergence of all forms of coronary heart disease is painless. The presence of microangiopathies and neuropathies with diabetes promotes the formation of painless variants of coronary heart disease (painless myocardial infarction, atypical attacks of angina pectoris), proceeding in the form of disturbances of heart rhythm and heart failure. In patients with diabetes, 2-fold painless myocardial infarction is found, which is associated with autonomic cardiac neuropathy.
With diabetes, the frequent form of coronary heart disease is -Mortality in acute (10 days) and subacute (4-8 weeks) periods myocardial infarction is 2 times higher than that in persons without diabetes.
In the presence of diabetes should strive for the possible elimination of all episodes of myocardial ischemia, and not only to arrest typical attacks of angina (getting rid of the "total ischemic burden" -total ischemic burden). This can be achieved by reducing the frequency and duration of episodes of STsegment depression in Holter electrocardiogram monitoring, which should be used more widely in patients with diabetes to evaluate the effectiveness of anti-ischemic treatment.

Diabetes mellitus and kidney damage
The earliest marker of kidney damage with diabetes is microalbuminuria; it is a harbinger of diabetic nephropathy and an important risk factor for the formation of cardiovascular pathology. Persistent albuminuria at the level of 30-299 mg / 24 h (or microalbuminuria) serves as a marker of nephropathy and at the same time a marker of the risk of developing coronary heart disease [22].

Diabetes mellitus and heart failure
The Framingham study quite convincingly confi rmed the The defeat of the heart with diabetes requires a preventive and curative effect.  The importance of accounting for long-term antihypertensive therapy of metabolic effects, and in particular the development of diabetes is emphasized in the latest European recommendations on arterial hypertension.

Treatment of chronic heart failure in patients with diabetes mellitus
Pathogenesis and treatment of chronic heart failure in patients with diabetes have certain characteristics that should be considered when conducting rational therapy. Treatment of heart failure in patients with diabetes generally corresponds to the generally accepted principles of therapy of chronic heart failure. However, an indispensable feature of the treatment of such patients is careful dynamic control over the basic metabolic parameters.
The main means of treatment of heart failure in diabetes are angiotensin-converting enzyme (ACE inhibitors) and angiotensin II receptor antagonists (ARAII), the effi cacy of which is superior, according to the Russian study by FASON [33,35], therapy for decompensation of blood circulation in patients without diabetes.
In a meta-analysis (SARRR study), comparing the effi cacy of angiotensin-converting enzyme (ACE inhibitors), -blockers, AC and diuretics in the treatment of patients with arterial hypertension and diabetes mellitus, it was shown that the administration of angiotensin-converting enzyme (ACE inhibitors) and angiotensin II receptor antagonists (ARAII) signifi cantly reduced the risk of acute myocardial infarction by 48%, cardiovascular accidents by 32%.
Priority is the modern cardioselective and non-selective -blockers with the properties of indirect vasalators (metoprolol, nebivolol, bisoprolol, carvedilol, etc.). The hemodynamic effects of carvedilol are a reduction in total peripheral vascular resistance and preload, an increase in cardiac output without refl ex tachycardia. In addition, the drug has antioxidant and antiarrhythmic activity, a vasoprotective effect. These properties make carvedilol very valuable in the treatment of patients with a combination of diabetes and chronic heart failure.
Active components reduce the frequency and duration of painless myocardial ischemia. It is preferable to use vasoselective and long-acting active components (amlodipine, felodipine, etc.) that do not cause refl ex tachycardia, an increase in the level of catecholamines, and a pro -cemic effect. In addition, active components have an anti-atherogenic effect.
Among diuretics, potassium-sparing agents (aldactone, veroshpiron), indapamide are used; caution should be given to loop and thiazide diuretics -under the control of carbohydrate metabolism and the level of potassium in the blood.
It is expedient to use metabolic means -trimetazidine, etc.

Conclusion
Type 2 diabetes mellitus substantially increases the lifetime risk of both developing and dying from heart failure.