The normal value of the fraction of cardiac output, the deviation of the indicator

From this article you will learn about the fraction of the cardiac output: the rate of the indicator, how it is calculated and what it shows. When the deviation of the ejection fraction( abbreviated as EF) is dangerous, why there is a pathological change. Symptoms of an output of a parameter for normal borders, principles of treatment and the forecast.

• • • • • is the ratio of the stroke volume( blood that enters the aorta in one contraction of the heart muscle) to the end-diastolic volumeventricle( blood that accumulates in the cavity during the relaxation period, or diastole, myocardium).The obtained value is multiplied by 100% and the final value is obtained. That is, this percentage of the blood that pushes the ventricle in the process of systole, from the total volume of the liquid contained in it.

          

          The indicator calculates the computer during the ultrasonographic examination of cardiac chambers( echocardiography or ultrasound).It is used only for the left ventricle and directly reflects its ability to perform its function, that is, to provide adequate blood flow throughout the body.

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          In physiological dormancy, a normal PV value is considered to be 50-75%, with physical activity in healthy people it increases to 80-85%.There is no further increase, since the myocardium can not throw all the blood out of the cavity of the ventricle, which will lead to cardiac arrest.

          In the medical plan, only the reduction of the index is estimated - this is one of the main criteria for the development of a decline in heart capacity, a sign of myocardial contractility. This is indicated by the value of PV below 45%.

          Such a failure represents a great danger to life - a small flow of blood to the organs disrupts their work, which results in multiple organ dysfunction and eventually leads to the death of the patient.

          

          Given that the reason for reducing the volume of the left ventricular ejection is its systolic insufficiency( as the outcome of many chronic pathologies of the heart and blood vessels), it is impossible to completely cure this condition. Treatment is carried out, supporting the myocardium and aimed at stabilizing the condition at one level.

          Cardiologists and therapists supervise and select therapy for patients with low ejection fraction. Under certain conditions, a vascular or endovascular surgeon may be required.

          Features of

          1. The ejection fraction does not depend on the gender of the person.
          2. With age, physiological decrease in the index is noted.
          3. Low PV can be an individual norm, but a value of less than 45% is always considered pathological.
          4. Increase in the value is in all healthy people with an increase in heart rate and blood pressure.
          5. The norm of the indicator for the measurement by radionuclide angiography is 45-65%.
          6. For the measurement using the Simpson or Teyholz formulas, the normal values, depending on the method used, fluctuate up to 10%.
          7. A critical level of decline of 35% or less is a sign of irreversible changes in the tissues of the myocardium.
          8. For children in the first years of life higher rates are typical in 60-80%.
          9. The indicator is used to determine the prognosis of any cardiovascular disease in patients.

          

          Causes of decrease in the

          index At the initial stages of any disease, the ejection fraction remains normal due to the development of adaptation processes in the myocardium( thickening of the muscular layer, strengthening of work, reconstruction of small blood vessels).As the disease progresses, the possibilities of the heart exhaust themselves, there is a disruption in the contractility of the muscle fibers, and the volume of ejected blood decreases.

          Such violations are caused by all influences and diseases that have a negative effect on the myocardium.

          reason	Diseases
          Reduced adequate coronary flow	All forms of angina( voltage quiescent, vasospastic) Acute myocardial infarction scarring of cardiac tissue( cardio) Silent ischemia form tachy and bradyarrhythmias ventricular aneurysm wall hypertensive disease Infectious
          -inflammatory processes in the heart	Myocarditis( muscular damage) Endocarditis( changes in the inner shell) Pericarditis( disease(
          ) Modification of the structure and function of myocardial tissue	All types of cardiomyopathies Myocardial dystrophy
          Greater stress on the heart chambers	Heart defects that occur in utero or acquired in the presence of rheumatic disease( large and decompensated defects) Pulmonary hypertension
          Vascular pathology	Vasculitis(inflammatory process in the wall of a vessel of a chronic nature) Congenital malformation of a normal structure or vicesa significant reduction in aortic lumen, a pathological junction between large vessels) Aneurysm of any aortic aorta Atherosclerotic lesion Aortoarteriitis( cell damage of the own immunity of the aortic wall and its branches) Vascular pulmonary embolism
          Endocrine system disorders	Dysfunction of the hormonal functionthyroid gland( hypo- and hyperthyroidism) Diabetes mellitus and impaired glucose uptake Hormone-active tumorsand adrenal glands( pheochromocytoma, carcinoid) Obesity
          Intoxication exposure	Alcohol Caffeine Nicotine Drug-stimulating drugs Energy drinks Cardiac glycosides

          

          Symptoms of reducing the

          The low ejection fraction is one of the main criteria for disrupting the heart, so patientsare forced to significantly restrict their labor and physical activity. Often even simple household chores cause a worsening of the condition, which causes most of the time to sit or lie in bed.

          The manifestations of the decrease of the indicator are distributed according to the frequency of occurrence from the most frequent to the rarer:

          • considerable loss of strength and fatigue from the usual loads;
          • breathing disorder by type of frequency increase, up to choking attacks;
          • breathing problems increase in prone position;
          • collapsoid states and loss of consciousness;
          • changes in vision( darkening in the eyes, "flies");
          • pain syndrome in the projection of the heart of varying intensity;
          • increased frequency of cardiac contractions;
          • edema of the shins and feet;
          • accumulation of fluid in the chest and abdomen;
          • gradual increase in the size of the liver;
          • progressive weight loss;
          • episodes of impaired coordination and gait;
          • periodic decrease in sensitivity and active mobility in the limbs;
          • discomfort, moderate pain syndrome in the projection of the abdomen;
          • unstable stool;
          • attacks of nausea;
          • vomiting with an admixture of blood;
          • blood in the stool.

          Treatment with decreasing

          Ejection fraction less than 45% - a consequence of changes in the functionality of the heart muscle against the background of the progression of the underlying disease-cause. Decrease in the index is a sign of irreversible changes in the tissues of the myocardium, and there is no longer any possibility of complete cure. All medical measures are aimed at stabilizing pathological changes at their early stage and improving the patient's quality of life - at a late stage.

          Treatment package includes:

          • correction of the main pathological process;
          • therapy for left ventricular failure.

          This article is devoted directly to the left ventricular ejection and the types of its disturbance, therefore further we will only discuss this part of the treatment.

          Dosage adjustment

          main drugs

          The destination	drugs Group	group representatives
          expansion of peripheral arterial Improving cardiac tissue supply Increased myocardial resistance load Significant increase in efficiency of the heart muscle	ACE inhibitors	enalapril Ramipril Captopril
          Reducing demandheart in nutrients and oxygen heartbeat Reduction of the processes of natural cardiac cell death in conditions of increased work Increase in the number of zones with active contraction in the myocardium	Beta-adrenoblockers	Nebivolol Bisoprolol Metoprolol
          Stabilization of the level of electrolytes in blood( potassium and sodium) Removing excess fluid and reducing the loadon myocardium	Antagonists of aldosterone receptors	Eplerenone Spironolactone
          Removal of accumulated excess fluid Reduction of bulkburden on myocardium	diuretics or diuretics	Torasemide Indapamide Hypothiazid
          Improved myocardial contractility conductivity Increase in conditions of impaired myocardial function	Cardiac glycosides	Digoxin Strofantin
          same as that of the ACE inhibitors, but with great effect	receptor antagoniststo angiotensin 2	Olmesartan Valsartan Candesartan

          

          Complementary funds

          Intended purpose	Drug group	Predstaviteli group
          Cholesterol Lowering vascular protection in a changing blood flow Statins		Simvastatin Pravastatin Fluvastatin
          Increased blood flow prevention of clot formation in the background of venous congestion	Anticoagulants Warfarin	Ksarelto Fraksiparin

          

          Supplements

          The destination	medicaments Group	group Representatives
          Reducing the load on the myocardium ventricle Improved blood flow in the heart vessels	Peripheral vasodilators	Nitroglycerin Sodium nitroprusside Apressin
          expansion to increase food cardiac vascular tissue	Calcium channel blockers	Nifedipine verapamil Nimodipine
          Obstruction to the formation of blood clots	Desaggregants	Plavix Aspirin
          CoupTreatment of myocardial contraction rhythmicity	Antiarrhythmics	Amiodarone Diltiazem Dysopyramide

          

          Surgical correction

          1. Pacemaker or cardiovector defibrillator for life-threatening heart rhythm disorders.
          2. Resynchronizing therapy - stimulation of contraction of ventricles and atria in different rhythm( slowing of ventricular contraction by creating an artificial heart block).

          

          Non-pharmacologic correction

          • Normalization of nutrition in accordance with the needs of the body to stabilize the normal weight.
          • Dosage, but mandatory physical activity.
          • Normalization of the work-rest mode.
          • Psychotherapeutic help.
          • Physio-and reflexotherapy.

          Forecast

          • If the left ventricular ejection fraction decreases, being in the range of 40-45%, the risk of a lethal outcome against a background of cardiac arrest is about 10-15%.
          • The reduction to a level of 35-40% raises this risk to 20-25%.
          • A further decrease in the exponent in the geometric progression worsens the prognosis for survival of the patient.

          There is no complete cure for the pathology, but timely therapy allows prolonging life and maintaining a relatively satisfactory quality.