Diabetic cardiomyopathy ‒ set of the pathological changes in heart caused by metabolic, vascular and electrolytic disorders at diabetes. The clinic of this state is various ‒ from an asymptomatic current to the expressed heart failure with short wind, hypostases, a kardialgiya, akrotsianozy. Diagnostics includes an electrocardiography, an echocardiography, a myocardium stsintigrafiya with thallium-201, functional tests. Treatment is complex, with obligatory correction of level of glucose in blood and application of cardioprotective means, medicines of potassium, tiazolidindion and statin.
The Diabetic Cardiomyopathy (DC) is allocated as a separate disease in 1973. It can arise at any type of the diabetes (D), and also be diagnosed for children if at pregnancy of their mother suffered from a hyperglycemia. This state is frequent is registered 10-15 years later after identification of the raised sugar level. However the term of development of pathology is very variable as it depends on a number of factors ‒ like diabetes, the scheme of its treatment, a diet, existence of other contributing factors. Statistically, damage of heart serves as the reason of a lethal outcome approximately at 20-25% of patients with a resistant hyperglycemia. But these figures are often challenged as accurately it is possible to differentiate the cardiomyopathy reasons at patients with diabetes not always.
Reasons of a diabetic cardiomyopathy
Insufficient production of insulin (the 1st SD type) or weakening of its impact on fabrics (the 2nd SD type) harmful influence cardiovascular system that is the most important reason of development of a cardiomyopathy. There are certain prerequisites increasing probability of damage of heart at diabetes, caused by both external, and internal factors. It explains the fact that the recreation center develops not at all patients with diabetes but only at their part. Allocate three main groups of the causes of this pathology:
- Violation of the mode of treatment and food. The neglect recommendations of the endocrinologist is the most widespread factor of development of recreation center. In case of non-compliance with a diet concentration of glucose periodically increases that promotes damage of kardiomiotsit. Similar to misuse of hypoglycemic means can break microcirculation in heart tissues, leading to their ischemia.
- Diabetes decompensation. In hard cases at permanent increase in level of glucose damage of a myocardium develops. Disorder of work of other bodies and systems (for example, a liver, kidneys, neurovegetative system) indirectly also leads to increase in load of heart. Therefore at the progressing diabetes practically there is always a recreation center, complicating an overall picture of a disease.
- Diabetic embriofetopatiya. In the presence at the pregnant woman of dekompensirovanny diabetes fruit heart can be surprised – there is rather rare children's disease which is characterized by a congenital kardiomegaliya and arrhythmia. It happens both because of a hyperglycemia, and because of impact of insulin and hypoglycemic medicines on development of the child
Besides, diabetes is one of risk factors of developing of the atherosclerosis affecting coronary vessels. However many authors the coronary heart disease developing because of diabetes and atherosclerosis does not belong to a true diabetic cardiomyopathy. As the rare reason of recreation center also injuries of heart as a result of use of low-quality hypoglycemic means act (for example, badly purified insulin medicines).
Three pathogenetic mechanisms – metabolic, angiopatichesky and neurovegetative take part in development of a diabetic cardiomyopathy. Most we mean the first option ‒ insulin insufficiency results in power deficiency in kardiomiotsit which compensate by its processes a proteoliz and a lipoliz. In a cardiac muscle accumulation of products of disintegration of lipids and amino acids results that involves increase in development of NO and other mediators of an inflammation. The acid and main balance in fabrics is displaced to acidosis, changing the transmembrane potential and concentration of inorganic ions. It reduces automatism and leads to violation of conductivity in heart. At the same time in fabrics the amount of the glikozilirovanny proteins and proteoglikan complicating delivery of oxygen to cages and aggravating a lack of energy increases.
The Angiopatichesky mechanism of injury of a myocardium at diabetes can develop as separately, and in combination with metabolic frustration. Sharp fluctuations of level of insulin stimulate the receptors intensifying proliferation of a gladkomyshechny layer of coronary vessels. It leads to their narrowing and additional decrease in perfusion of a myocardium. A result of this process is the mikroangiopatiya which is complicated by damage an endoteliya and aggravating the ischemic phenomena. Also there is a growth of abnormal collagen in tissues of a cardiac muscle that changes its density and elasticity.
The dystrophy of neurovegetative system affecting heart arises at final stages of development of recreation center. As a rule, direct defeat of kardiomiotsit and vessels develops earlier. As a result of a hyperglycemia, and also a diabetic gepatoz (at a deep decompensation of diabetes) there is an injury of the autonomic nervous system. Its fibers demiyelinizirutsya, and the centers can be damaged as a result of a lack of glucose and ketoacidosis. On this background there is a vagusny denervation of heart which is shown violation of a rhythm of its reductions. Set of these processes leads to an ischemic disease, increase in volume of a myocardium and finally ‒ to heart failure.
In cardiology allocate several kinds of a diabetic cardiomyopathy, classification is based on etiologichesky and pathogenetic features of a disease. In spite of the fact that several mechanisms are involved in development of pathology at once, usually one of them is expressed stronger than the others. Knowledge of the leading scenario of pathogenesis allows the expert to correct treatment for its bigger efficiency at the specific patient. Now three forms of recreation center are known:
- Primary form. At this option the main role in damage of a myocardium is played by the metabolic frustration connected with accumulation in fabrics of products of metabolism of fats and glikozilirovanny proteins. Is a widespread type of a disease, but it is often characterized by an asymptomatic current and incidentally comes to light at inspection of the patient having diabetes.
- Secondary form. Can initially arise or as a result of progressing of metabolic violations. At this type coronary arteriola are surprised, microcirculation worsens, perfusion decreases, and myocardium ischemia develops. Some cardiologists carry to this option and coronary atherosclerosis of a diabetic etiology.
- Embriofetopatichesky type. The rare form which is diagnosed for children whose mothers suffered from diabetes. Many experts challenge the relation of this pathology to a diabetic cardiomyopathy.
Symptoms of a diabetic cardiomyopathy
From the moment of the beginning of damage of heart to the first symptoms of a disease there can pass the long time ‒ from several months to 4-6 years. Most often patients complain of the pains in heart reminding ischemic ‒ the pressing feeling in the left half of a thorax. However their expressiveness is much weaker, than at stenocardia, irradiation in a neck, a shovel zone, the left hand is also not characteristic. Originally the kardialgiya appears after physical activity or the admission of reception of insulin, but further can arise also in a quiet state. An important diagnostic sign is lack of reaction to reception of nitrates ‒ nitroglycerine does not eliminate pain.
At a part of patients the pain syndrome does not develop, but short wind, takes place, dizziness ‒ they also arise both against the background of loadings, and without those. Duration of an attack makes of several minutes till 1-3 o'clock then (at the initial stages of a disease) kardialny symptoms weaken. At the started forms of recreation center patients point to almost constant breast pain, weakness, dizziness and headaches. Even the weakest loadings (rise on a ladder, the quickened pace) cause severe short wind, cough and strengthening of unpleasant feelings.
In the absence of treatment, continuation of violation of the food mode, nekorrigiruyemy hyperglycemia the diabetic cardiomyopathy leads to the accruing heart failure of stagnant character. As a result of it cardiogenic hypostasis of lungs and dystrophy of a liver can develop. These phenomena considerably aggravate the course of diabetes and threaten the patient's life. Weakness of a myocardium also promotes microcirculation violation, especially on disteel sites of extremities that in a complex with a mikroangiopatiya leads to formation of trophic ulcers and gangrenes. Chronic ischemia of a myocardium considerably facilitates development of a heart attack, small - and a krupnoochagovy cardiosclerosis.
Early diagnostics as it considerably reduces risk of complications is important for successful treatment of a diabetic cardiomyopathy and slows down progressing of pathology. For this purpose sick diabetes it is regularly necessary to undergo inspection at the cardiologist even in the absence of subjective symptoms. In clinical practice use a set of the techniques allowing to differentiate recreation center from other cardiovascular diseases and to define type and a stage of a disease for development of the effective scheme of treatment. Most often at a cardiomyopathy the following diagnostic technicians apply:
- Electrocardiography. Simple and effective method of monitoring of warm activity and identification of early changes in a cardiac muscle. At patients with recreation center picture ECG is similar to an ischemic disease ‒ ST segment shift, smoothing of the QRS complex, deformation of a tooth of T. In process of progressing of pathology decrease in a voltage, change of an electric axis of heart, arrhythmia is also possible.
- Echocardiography. At this research the thickening of walls of ventricles, increase in lump of heart and change of density of a myocardium comes to light. At the same time decrease in sokratitelny ability of a cardiac muscle and volume of emission of blood is found. At the long course of pathology it is possible to see signs of a dilatatsionny cardiomyopathy or a focal cardiosclerosis.
- Perfuzionny stsintigrafiya of a myocardium. Radio nuclide studying of intake of blood to tissues of heart is made by means of RFP containing thallium-201. This technique allows to reveal the earliest signs of a coronary mikroangiopatiya (secondary recreation center) on the basis of decrease in intake of medicine in a myocardium. However at early stages of primary diabetic cardiomyopathy test results can be ambiguous.
At easy forms of a disease quite often appoint a veloergometriya for detection of changes to the ECG during physical activities that allows to specify the diagnosis. Also sick biochemical blood test within which the level of glucose, lipoproteid, heart and hepatic enzymes is defined is carried out. Coronary angiography is necessary at suspicion of atherosclerosis of vessels of heart. All these techniques allow to distinguish recreation center from the ischemic disease and other states which are directly not connected with diabetes.
Treatment of a diabetic cardiomyopathy
Therapy of this state multicomponent is also inseparably linked with treatment of the main disease ‒ diabetes. The adequate diet, constant control of level of sugar in blood, elimination of sharp jumps of level of insulin even without reception of heart medicines are capable to improve a condition of the patient considerably. But in some cases the recreation center is found already in quite started state demanding intervention of the cardiologist. For delay of progressing and treatment of a cardiomyopathy at diabetes use the following groups of medicines:
- Tiazolidindiona. These hypoglycemic medicines selectively slow down division of gladkomyshechny cages coronary , interfering with reduction of their gleam and deterioration in perfusion of a myocardium. However they are admissible to be used only at the proved defeat of microcirculator network of heart – in rare instances they can cause kardiopatichesky influence which reasons are not clear.
- Potassium medicines. At recreation center shortage of ions of potassium in kardiomiotsita is a consequence of metabolic frustration. Its deficiency can be also caused by the raised diuresis that is quite often observed at diabetes, violation of a diet, reception of some drugs. Medicines of potassium fill up quantity of a microcell in an organism, normalizing electrolytic structure and membrane potential of cells of a myocardium.
- Statins. At a number of patients the giperlipidemiya which increases risk of development of the atherosclerosis complicating a current of a cardiomyopathy is observed. These means, for example, , reduce the level of dangerous LPNP, and also eliminations from tissues of heart of products of splitting of fats promote. In the long term use of statin increases life expectancy of patients with diabetes and sharply reduces risk of heart attacks and strokes.
- Beta . They are appointed at the expressed ischemic changes in a myocardium or development of a takhiaritmiya. They reduce heart rate and reduce the need of a myocardium for oxygen, improving his metabolism. Use of beta-blockers at dystrophy of vegetative nerves which normal promote decrease in heart rate is especially urgent.
According to indications various hypoglycemic means (can be applied especially at diabetes of the 2nd type), APF inhibitors, blockers of calcic channels, antioxidants. In the presence of stagnant heart failure and development of hypostases appoint diuretichesky medicines with constant control of ionic composition of plasma of blood. As the supporting treatment at irregular shapes of a cardiomyopathy use warm glycosides.
Forecast and prevention
Predictive prospects of a diabetic cardiomyopathy are closely connected with the course of the main disease. At the adequate hypoglycemic therapy including both administration of drugs, and a way of life of the patient, speed of progressing of pathology is significantly slowed down, and use of cardioprotective means helps to eliminate kardialny symptoms. At the same time, ignoring of a disease and neglect to the food mode against the background of diabetes can lead to heavy heart failure. Prevention of recreation center comes down to prevention of increase in level of glucose and prevention of development of a decompensation of diabetes, regular observation at the endocrinologist. It is especially important to follow these rules to pregnant women ‒ them children can receive pre-natal damage of heart.