chest heaviness
Introduction
Introduction Hyperthyroidism has less angina pectoris, mostly coronary artery blood supply is relatively insufficient, and it is more common in the chest or chest.
Cause
Cause
(1) Causes of the disease
Hyperthyroidism can cause abnormalities in the heart, called hyperthyroidism (hyperthyroid heart disease). However, many patients with hyperthyroidism can be accompanied by existing heart disease, such as atherosclerotic heart disease, hypertensive heart disease, rheumatic heart disease and congenital heart disease. It is said that infection can be a cause of hyperthyroidism.
Animal experiments have shown that thyroxine can cause cardiac hypertrophy in rats. In clinical observation, patients with hyperthyroidism, after treatment of hyperthyroidism, 60% of their heart disease was relieved with the improvement of hyperthyroidism without special treatment. Hyperthyroidism can occur independently or on the basis of other causes of heart disease. At this time, hyperthyroidism is only a trigger for the exacerbation of the original heart disease.
Pathological findings showed no specific pathological changes in the myocardium of hyperthyroidism.
(two) pathogenesis
1. The effect of thyroid hormone on the heart
(1) Indirect effects of thyroid hormone on the heart: Hyperthyroidism is excessively secreted during hyperthyroidism, resulting in hypermetabolism, increased oxygen consumption in the body, excessive heat production, and a marked change in hemodynamics to accommodate high metabolic status. Capillaries of the skin can be dilated, and the blood volume of the whole body can be increased by more than 10%; the blood flow velocity is increased, the venous return flow is increased, and the cardiac load is greatly increased. The long-term sustained overload of the heart, abnormal changes in function and morphology, the modern compensatory cardiac hypertrophy, and finally lead to heart failure. Mainly due to right heart failure, the reason is that the amount of blood return to the heart, pulmonary artery and right ventricular pressure increased significantly, plus the right ventricular myocardial reserve capacity is worse than the left ventricle.
(2) direct effect of thyroid hormone on the heart: 1 thyroxine receptor on the inner side of myocardial cell membrane, thyroxine can directly act on the myocardium, accelerate myocardial metabolism and oxygen consumption process; increase myocardial cell calcium storage, make myocardial fiber phosphoric acid The concentration of root ions, creatine and calcium ions increased, the concentration of potassium ions decreased, the refractory period of various myocardial fibers decreased, and the threshold of excitation decreased. This is one of the causes of atrial fibrillation and other arrhythmias in patients with hyperthyroidism. 2 myocardial metabolic process changes. Thyroid hormone activates ATPase in cardiomyocytes, increases cAMP, stimulates the action of catecholamines, increases the sensitivity of cardiac beta receptors to catecholamines, increases sensitivity to hypoxia, leads to coronary spasm, transient embolism and Microcirculatory disorders, etc., are the main causes of angina pectoris. 3 The direct action of thyroxine can enhance cardiac activity, ie, increased heart rate, increased myocardial contractility, and increased myocardial oxygen consumption. This has an adaptive meaning in the early stage, but because the heart rate continues to accelerate (including in the resting state), the diastolic phase is significantly shortened, the myocardial recovery is incomplete, and the long-term fatigue state increases the myocardial sensitivity to myocardial hypoxia, resulting in myocardial The contraction force is reduced. For a long time, the heart reserve capacity is exhausted, and heart failure can occur. 4 thyroid hormone acts on the myocardium, can cause certain pathological changes, such as lymphocytes and eosinophil infiltration, fatty infiltration, fibrosis, and even focal ischemic necrosis, called hyperthyroidism . These pathological changes can cause hyperthyroidism, especially one of the causes of arrhythmia or conduction abnormalities.
2. Enhanced adrenergic activity
Patients with hyperthyroidism have increased sensitivity to adrenaline and catecholamines, and may have tachycardia and arrhythmia.
Examine
an examination
Related inspection
Dynamic electrocardiogram (Holter monitoring) ECG
1. Hyperthyroidism and arrhythmia: Arrhythmia is the most common form of hyperthyroidism, including sinus tachycardia, pre-atrial contraction, paroxysmal tachycardia, ventricular flutter, atrial fibrillation, the most common of which is atrial fibrillation. It has been reported that approximately 5% to 15% of patients with hyperthyroidism have atrial fibrillation, which increases with age. Some patients can see atrial fibrillation as the only symptom. A large study suggests that nearly 1% of newly occurring atrial fibrillation is caused by hyperthyroidism, and 13% of unexplained atrial fibrillation also has biochemical evidence of hyperthyroidism. Therefore, routine thyroid function should be performed for newly occurring atrial fibrillation. Check to rule out hyperthyroidism. Occasionally, hyperthyroidism complicated with high atrioventricular block, its mechanism may be related to myocardial histological changes caused by hyperthyroidism, myocardial lymphocytes and eosinophils infiltration and mitochondrial pathological changes, when these pathological changes affect myocardial conduction Atrioventricular block can occur in the system.
The pathophysiological basis of hyperthyroidism is not fully understood. The formation of multiple reentry loops is the basis of atrial fibrillation. At the time of hyperthyroidism, the activity of Na-K-ATPase in cardiomyocytes is enhanced, which promotes the outflow of Na, and the influx of K affects the electrophysiology of cardiomyocytes. The most significant electrophysiological abnormality in experimental hyperthyroidism is that the action potential time of a single atrial myocyte is shortened, and as a result, the electrical excitability of the atrium is increased, and atrial fibrillation may occur.
2. Hyperthyroidism and heart enlargement: Long-standing untreated hyperthyroidism can cause prominent changes in heart shape, including atrial or ventricular enlargement, increased cardiac weight, cardiomyocyte hypertrophy, and widening of myocardial fibrosis. These changes occur after thyroid function returns to normal. Can be improved or reversed. Causes of hyperthyroidism: 1 High-powered circulation: T3, T4 elevation caused significant hemodynamic changes, manifested as increased peripheral oxygen consumption in the tissue and myocardium, increased circulating blood volume, increased cardiac output, and long-term cardiac Excessive volume load can cause heart enlargement; 2T3 elevation can directly promote myocardial protein synthesis and myocardial cell growth, causing cardiac hypertrophy; 3 thyroid hormone can be independent or added to the action of catecholamine, increasing endogenous The sensitivity of catecholamines, induced by -receptor-induced cardiac hypertrophy; 4 renin-angiotensin-aldosterone system (RAAS) and atrial natriuretic peptide (ANP), hyperthyroidism when the surrounding tissue vasodilatation, the kidney Reduced blood flow, decreased effective perfusion pressure, thereby activating RAAS, resulting in sodium retention, although ANP is also elevated, but not sufficient to combat activated RAAS.
3. Hyperthyroidism and heart failure: It is reported that the incidence of congestive heart failure in patients with hyperthyroidism is about 6%, and the age is greater than 60 years old. The occurrence of heart failure is related to the following factors: 1 high-powered circulation state of hyperthyroidism makes myocardial load long-term overweight, can cause heart enlargement, cardiac output increases; 2 myocardial oxygen consumption increases, energy metabolism disorder; 3 rapid arrhythmia In particular, atrial fibrillation, decreased cardiac output; 4RAAS activation can lead to cardiac hypertrophy and increased blood volume. The characteristic of heart failure is that right heart failure is more common, and left heart failure can also occur. We have analyzed the color Doppler echocardiography of 68 patients with hyperthyroidism who were hospitalized. Most of the patients showed bilateral atrial enlargement, which was more common in the left atrium. Especially in patients with atrial fibrillation, the left atrium was prone to enlargement. Ventricular enlargement is also evident in the right ventricle; valvular regurgitation is common, and despite the presence of right heart failure, the heart failure ejection fraction (EF) can still be within the normal range. Rarely have refractory heart failure, which may be caused by autoimmune-related cardiomyopathy.
4. Angina pectoris and myocardial infarction: Hyperthyroidism occurs with less angina pectoris, mostly coronary artery blood supply is relatively insufficient, chest or chest heaviness is more common, myocardial infarction is rare, with coronary spasm, microcirculatory disorders and It is related to abnormal blood rheology.
Because the clinical manifestations of hyperthyroidism have no significant specificity, they are easily confused with other cardiovascular diseases, resulting in clinical misdiagnosis or missed diagnosis, especially in the elderly. On the one hand, patients have a long history of cardiovascular disease (such as coronary heart disease, high heart disease or pulmonary heart disease), and the typical symptoms of hyperthyroidism are absent, which masks the performance of hyperthyroidism and causes poor cardiovascular treatment. It is even ineffective, and it also delays the treatment time of hyperthyroidism. On the other hand, patients with confirmed hyperthyroidism have cardiovascular symptoms caused by other diseases, but are misdiagnosed as hyperthyroidism and can also cause therapeutic effects. The decline and delay in treatment time cause physical, psychological and economic losses to the patient. In all aspects, the diagnostic criteria for hyperthyroidism should include: 1 diagnosis of hyperthyroidism; 2 hyperthyroidism with one or more cardiac abnormalities; (including arrhythmia, heart enlargement, heart failure, mitral valve prolapse with heart Pathological murmur); 3 rule out other causes of heart disease; 4 regular anti-thyroid treatment, cardiovascular symptoms and signs basically disappear.
Diagnosis
Differential diagnosis
Differential diagnosis of chest heavy feeling:
1. Chest tightness or belt sensation: The number of peripheral white blood cells is normal or slightly higher, which may be significantly increased by bacteria or bacterial infection. X-ray examination of lung texture thickening or hilar shadow darkening.
2, chest pain with chest tightness, palpitations: chest pain with chest tightness, palpitations, at the same time or before, there are fever, body aches, sore throat, diarrhea and other symptoms, can be seen in acute myocarditis.
3, the chest is tight: the sympathetic nerve is a kind of autonomic nerve, the autonomic nerve controls our heartbeat, blood pressure, sucking, heart beat and so on. People with autonomic dysfunction, that is, people with strong sympathetic activity, causing nerve tension or tightness, if they are tight in the chest, they will produce chest tightness, tight chest pain, and poor cardiovascular delivery; if they are tight, then Depressed, anxious, nervous, worried, etc., feel pressure at any time.
4, chest tightness: chest distress chest distress is a subjective feeling, that is, breathing is not enough or gas is not enough. If the light person has nothing to do, the heavy one feels uncomfortable. It seems that the stone is pressed against the chest and even breathing difficulties occur. It may be a functional manifestation of a body organ or it may be one of the earliest symptoms of a disease in the human body. People of different ages have chest tightness, the cause is different, the treatment is different, and the consequences are different.
