HEART FAILURE - a pathological condition in which the cardiac output does not meet the needs of the body due to a decrease in the pumping function of the heart. The cause may be overload of the heart with increased blood volume or blood pressure (with heart defects, hypertension, pulmonary heart, etc.), as well as a decrease in myocardial contractile function with a decrease in its mass (Myocardial infarction, post-infarction cardiosclerosis , heart aneurysm , etc. ), degenerative changes (with amyloidosis, hemochromatosis, etc.), myocarditis, cardiomyopathy, myocardial dystrophy of various etiologies.
In clinical practice, there are acute and chronic, left ventricular and right ventricular failure, as well as three stages of circulatory failure. Stage I is characterized by shortness of breath, tachycardia, fatigue only during physical exertion. In stage II, clinical signs of stagnation in organs and tissues appear, accompanied by reversible dysfunctions of their function. This stage is divided into HA (signs of stagnation are not clearly expressed and are determined mainly only in the small or only in the large circle of blood circulation) and IIB (significant hemodynamic disturbances are detected in both circles of blood circulation, accompanied by swelling of organs and tissues). In stage III, the signs characteristic of stage IIB are joined by irreversible morphological changes in organs due to their prolonged hypoxia, protein dystrophy, the development of sclerosis in them (pulmonary hemosiderosis, liver cirrhosis , etc.). The preclinical stage of heart failure is also distinguished, the recognition of which is possible only under stress tests using special instrumental methods.
The pathogenesis of heart failure depends on its causes. In most cases, the reduction of myocardial contractility, which is almost always due to a violation of the energy supply of heart contractions as a result of insufficient education and a decrease in the efficiency of ATP use in the heart muscle, is of primary importance. This is facilitated by a decrease in oxygen delivery to the heart muscle (with hypoxemia in patients with respiratory failure, anemia , decreased blood flow in the myocardium), increased use (with myocardial hyperfunction caused by heart overload, thyrotoxicosis, etc.), incomplete utilization of it by the heart muscle due to lack of certain enzymes (for example, with diabetes mellitus, vitamin B deficiency, etc.). Dysfunctions of the cell membranes (with any forms of myocardial dystrophy), leading to a change in the flow of cations (sodium, potassium, calcium) through the membrane into the phases of systole and diastole, and thereby to a decrease in cardiac contraction force, are also of significant pathogenetic importance.
In case of insufficiency of the left ventricle of the heart, an increase in venous pressure and fluid retention occur in a small circle, and in case of right ventricular failure - in a large circle of blood circulation, which is accompanied by an increase in the liver, acrocyanosis, swelling on the legs, and in severe degrees of right ventricular failure - ascites, hydropericardium, hydrothorax. With the appearance of edema, the resistance to blood flow in the tissues and, accordingly, the load on the heart increase even more, contributing to the progression of heart failure: With left ventricular heart failure, stagnation in the veins of the pulmonary circulation is accompanied by a reflex increase in the tone of the pulmonary arterioles, which prevents the development of edema, but the pressure in the pulmonary trunk increases and the right ventricle of the heart, causing its overload, which over time leads to right ventricular failure.
The clinical manifestations are diverse and are determined by the nature of the heart disease, the severity of violations of myocardial contractility and intracardiac hemodynamics, the predominant involvement of the left or right heart in the pathological process, as well as the duration of the disease. The speed of development distinguish acute heart failure that occurs almost suddenly or within a few hours, and chronic, developing within a few weeks, months, years.
Acute left ventricular failure is most often manifested by cardiac asthma and pulmonary edema in patients with acute myocardial infarction, after physical overload in patients with certain heart defects, left atrial myxoma, can sometimes be triggered by hypertensive crisis or paroxysm of arrhythmia . With thromboembolism of the pulmonary arteries, as well as with a rupture of the interventricular septum, acute right ventricular failure develops; with myocarditis, poisoning with cardiotropic poisons - usually right- and left ventricular at the same time.
Chronic heart failure in the early stages of development is manifested mainly by symptoms of a decrease in cardiac output: fatigue, muscle weakness, feeling of lack of air, coldness. During exercise, shortness of breath , a feeling of palpitations are observed. As heart failure progresses, complaints begin to prevail, reflecting the development of stagnation in organs (stage II of circulatory failure). With left ventricular failure, dyspnea comes to the forefront with less physical exertion, and then it occurs at rest, especially with the horizontal position of the body, because of which patients prefer to sit or stand - orthopnea. Attacks of suffocation appear at night - cardiac asthma ; physical activity can lead to the development of pulmonary edema. With the progression of right ventricular failure, patients complain of a decrease in daily diuresis, the appearance of edema in the feet and legs by the end of the day. Then the edema becomes constant, widespread, but more pronounced in the lower parts of the body - hypostatic edema. The abdomen is enlarged due to flatulence, congestive enlargement of the liver, later ascites. Nausea and loss of appetite (congestive gastritis) are possible. With mitral stenosis, cough and hemoptysis often appear.
When examining a patient , symptoms are often identified that indicate the cause of heart failure (signs of heart disease, pulmonary heart disease, arterial hypertension , etc.). Of the symptoms of left ventricular failure, orthopnea, the expansion of the boundaries of relative cardiac dullness to the left with a weakened and diffuse apical impulse (the sign of dilatation of the left ventricle) are of greatest importance; tachycardia in combination with a pendulum-like rhythm; deaf I tone (or its weakening) in the presence of an accent II heart tone over the pulmonary trunk; gallop rhythm, the presence of wet (stagnant) rales in the lower parts of the lungs. The main signs of right ventricular failure include swelling of the cervical veins, which does not disappear on inspiration; acrocyanosis; the presence of edema; expansion of the borders of the heart to the right (a sign of dilatation of the right atrium); the appearance of systolic murmur over the xiphoid process; enlargement of the liver, the edge of which during palpation is determined without difficulty in the absence of ascites; the presence of hydrothorax. At the same time, all signs are rarely detected. In the terminal stages of heart failure, patients are usually exhausted, lethargic, dynamic. cyanosis is combined with pallor and yellowness of the skin. The liver as a result of the development of cirrhotic changes becomes very dense and does not decrease in size when using diuretics. Often there is ascites . When a blood test is often revealed violations of its coagulability. Protein is almost always found in urine.
The diagnosis of heart failure in patients with heart disease is not difficult and is established by the characteristic clinical signs without the use of additional research methods. The latter (especially echocardiography) are necessary to determine the preclinical stage of heart failure. For the purpose of early diagnosis of heart failure, it is also advisable to assess patient tolerance of physical activity. Complaints about the appearance of shortness of breath and palpitations with minor physical exertion (climbing stairs to the 2nd – 3rd floor), inadequate changes in cardiac output during exercise tests (on a bicycle ergometer) indicate the presence of latent heart failure. The differential diagnosis is more often carried out with respiratory failure, in which dyspnea usually has an expiratory character (difficulty and prolonged expiration) and does not increase in the horizontal position of the body; cyanosis is diffuse, i.e. characteristic of pulmonary failure. According to the history and examination of the patient, the presence of bronchopulmonary pathology is detected. In patients with chronic lung diseases, a combination of heart and pulmonary failure is possible in the case of development and decompensation of pulmonary heart.
Treatment . In acute heart failure, emergency treatment is performed according to clinical manifestations and causes. Treatment begins at the site of recognition of acute heart failure and continues in the hospital. In most cases, intravenous administration of diuretics, cardiac glycosides, the use of peripheral vasodilators are indicated, and oxygen inhalations are used if possible.
The treatment of chronic heart failure is mainly carried out on an outpatient basis, in addition to the treatment of the underlying disease (for example, coronary heart disease), limiting physical activity and psychoemotional stress, physical therapy, using a protein and vitamin-rich diet with sodium chloride limited to 3-4 g day (sometimes up to 1-2 g per day) and fluids (up to 800-1200 ml per day), drug effects on the pathogenetic links of heart failure. The main pathogenetic treatment for chronic heart failure, which developed against the background of ciliary tachyarrhythmia, are cardiac glycosides. Parenteral administration of strophanthus, korglikon, digoxin . For oral administration, digoxin , celanide , etc. are prescribed. The doctor selects the dose of cardiac glycosides. The average medical worker helps to monitor the effectiveness of the selected dose (according to the dynamics of shortness of breath, edema, patient tolerance, etc.) and its safety.
In the presence of peripheral edema, hydrothorax, ascites, diuretics are used - lasix (furosemide), uregitis , hypothiazide , etc. sometimes in combination with aldosterone antagonists (veroshpiron for hyperaldosteronism) and potassium preparations (potassium chloride, etc. with hypokalemia). For prolonged use, potassium-sparing diuretics (triamteren, triampur) are used. These funds are prescribed by the doctor; the average health worker helps to control their effect by measuring the diuresis and body weight of the patient in dynamics. In the process of treatment with diuretics, it is periodically necessary to examine the content of potassium, sodium, uric acid in the blood and indicators of acid-base balance.
In most cases, it is advisable to prescribe drugs that improve hemodynamics as a result of peripheral vasodilating action (vasodilators). First of all, angiotensin-converting enzyme inhibitors (capoten, enalapril , kyulapril, etc.) are used, acting on both arterial and venous vessels. Less commonly, nitrates are used - nitroglycerin , nitrosorbide (mainly reduce the tone of the veins), apressin, phentolamine (expand the arterioles), sodium nitroprusside, prazosin (act on the tone of arterioles and venules). With their use, a decrease in blood pressure, the appearance or intensification of tachycardia, the development of edema resistant to the action of diuretics are possible. Prescribes vasodilators and controls the effect of their action only a doctor.
The prognosis depends on the nature of the heart disease, as well as on the severity of heart failure (in acute form) and the stage of circulatory failure (in chronic form). With the timely and complete elimination of the causes of heart failure (for example, by surgical treatment of heart disease), the prognosis is favorable. Rational complex therapy And dispensary monitoring of patients with chronic heart failure increase the tolerance of the load and delay the lethal outcome. With irreversible changes in the internal organs, the prognosis is poor.
Prevention in patients with existing heart failure is aimed at combating exacerbations and the progression of the underlying disease, preventing its complications, as well as ensuring the proper mode of physical activity through proper employment of the patient.