Viral myocarditis is acute or chronic inflammation of myocardium caused by virus. It usually occurs within 1-3 weeks after virus infection (such as cold, sore throat, diarrhea, etc. ). There are many viruses that cause myocarditis, mainly through respiratory tract or intestinal infection, and a few hepatitis patients may have myocarditis. Viruses can directly damage myocardium, and can also cause myocardial inflammation through immune mechanism.
Often attracted attention due to chest pain or palpitations. Electrocardiogram examination can find arrhythmia or myocardial damage. It is helpful for further diagnosis and treatment to draw blood for etiology, myocardial zymogram examination or myocardial biopsy.
The severity of the illness varies greatly, and the patient has no discomfort or occasional premature beats; Serious people have serious arrhythmia, heart failure and even life-threatening. Severe myocarditis is easy to diagnose, but mild myocarditis is difficult to diagnose. Those who only have premature beats and diagnose myocarditis are mostly speculations.
treat cordially
1. In the acute phase, stay in bed (1-6 months) and use myocardial nutrition drugs and immune enhancers. Recovery period (6- 12 months) can gradually increase the activity, but don't be too tired. Chronic myocarditis (the course of disease is more than one year, the condition is recurrent, accompanied by enlargement of the heart) should pay attention to long-term rest and drug treatment.
2. Eat more fruits containing vitamin C (such as oranges and tomatoes) and foods rich in amino acids (such as lean meat, eggs, fish and soybeans).
3. Pay attention to climate change to prevent colds, colds or upper respiratory tract infections.
4. Take medicine according to the doctor's advice, especially for patients with arrhythmia (such as frequent premature beats). ). Don't increase or decrease the dose by yourself.
myocarditis sequela
Mild myocarditis generally has no sequelae, or only occasional premature beats. After recovery, patients can fully recover and rarely relapse.
Severe myocarditis may have sequelae, mainly manifested as enlargement of the heart (which can be found by echocardiography, chest X-ray and chest fluoroscopy) and severe arrhythmia (which can be found by ECG and hourly ECG examination). Patients with long-term persistent premature beats should avoid strenuous activities and pay attention to the law of life.
Patients with premature beats without cardiac enlargement have a better prognosis. Those with more premature beats can take antiarrhythmic drugs for a short time, or even do not need to take them (unless doctors think it is necessary), because the side effects of drugs may outweigh the damage to the heart caused by long-term premature beats. Keep a good mental state and don't be too nervous because of premature beats.
Patients with enlarged heart should be treated with drugs for a long time to avoid heart failure.
Diagnostic reference standard of adult acute viral myocarditis and its application
Adopt the opinions of the World Health Organization Working Group and the International Federation of Cardiology Societies on the definition and classification of cardiomyopathy.
Editorial Committee of Chinese Journal of Cardiology: Myocarditis and Cardiomyopathy Countermeasures Special Group
1At the National Symposium on Myocarditis and Cardiomyopathy held in Zhenjiang from August 6 to 8, 1999, sponsored by Cardiovascular Branch of Chinese Medical Association, Editorial Board of Chinese Journal of Cardiology, Institute of Clinical Cardiovascular Diseases of the First Affiliated Hospital of Nanjing Medical University, Zhongshan Hospital of Shanghai Medical University and Shanghai Cardiovascular Institute,1in Zhangjiagang in June, 1988,1in June, 1995. Because the diagnosis of viral myocarditis is difficult, there is no unified standard in the world so far, so the diagnostic standard revised at this meeting is still a reference scheme.
1995 the report of the working group of the world health organization and the international Federation of cardiology societies (who /ISFC) on the definition and classification of cardiomyopathy was formulated after serious discussion by most international experts engaged in cardiomyopathy research, and can be adopted and applied in China. However, the expert group of this meeting has different views on the formulation of some specific cardiomyopathy, which is listed separately for colleagues' reference.
Diagnostic reference standard of adult acute viral myocarditis
Myocarditis refers to localized or diffuse acute or chronic inflammatory lesions in myocardium, which can be divided into infectious and non-infectious types. The former is caused by infections such as bacteria, viruses, spirochetes, rickettsia, molds, protozoa and worms, while the latter includes allergic or allergic myocarditis such as rheumatism and myocarditis caused by physical and chemical factors or drugs. Acute viral myocarditis is caused by viral infection, and the course of disease is within 3 months.
Symptoms of myocarditis vary in severity. Mild people may not have conscious symptoms; Severe cases can be manifested as sudden death, severe arrhythmia, cardiogenic shock or (and) heart failure, leading to acute death; It can also be manifested as various arrhythmia, pericarditis or acute myocardial infarction. The clinical manifestations of adult viral myocarditis are mostly lighter than those of newborns and children, with low mortality in acute stage and good prognosis in most cases. However, a small number of fulminant and severe patients may have persistent cardiac cavity enlargement and/or cardiac insufficiency after acute phase, and their clinical manifestations are similar to dilated cardiomyopathy, also known as "subacute or chronic myocarditis" and "dilated cardiomyopathy syndrome". The natural course of these patients is different. Some patients have progressive development, heart cavity enlargement and death due to heart failure; There are also a few cases of heart cavity enlargement without clinical manifestations of heart failure. After several months to several years, the heart function improved and remained stable without treatment. Some of them may get worse again and have a poor prognosis.
The diagnosis of viral myocarditis is quite difficult. The reason is that the clinical manifestations and most auxiliary tests of viral myocarditis lack specificity. There is no uniform international standard on how to diagnose viral myocarditis by combining clinical manifestations with laboratory examination results. Symptoms of viral infection or myocarditis alone are not enough to diagnose viral infection in myocardium. At present, the clinical diagnosis of acute viral myocarditis in China is mostly wide. Patients with a history of viral infection and premature beats or only nonspecific symptoms such as chest tightness and palpitation were diagnosed as acute viral myocarditis, which caused a certain mental and economic burden to patients. In order to further strengthen clinicians' understanding of acute viral myocarditis, this seminar was revised on the basis of the last two drafts of diagnostic criteria as a reference for the diagnosis of acute viral myocarditis at this stage.
I. Medical history and signs
Cardiac manifestations occur within 3 weeks after upper respiratory tract infection, diarrhea and other viral infections, such as severe fatigue, chest tightness, dizziness (caused by decreased cardiac output), obvious weakening of the first heart sound at the apex, galloping during diastolic period, pericardial fricative sound, cardiac enlargement, congestive heart failure or Asperger's syndrome, and the general reasons cannot be explained.
Two, the following new arrhythmia or ECG changes occurred within 3 weeks after infection.
1. Sinus tachycardia, atrioventricular block, sinoatrial block or bundle branch block.
2. Multi-source, paired ventricular premature beats, autonomic atrial or junctional tachycardia, paroxysmal or non-paroxysmal ventricular tachycardia, atrial or ventricular flutter or fibrillation.
3. The ST segment above two leads moves horizontally or obliquely downward ≥0.0 1 mV, or the ST segment is abnormally elevated or abnormal Q wave appears.
Third, the reference index of myocardial injury
During the course of the disease, serum cardiac troponin I or troponin T (emphasizing quantitative determination) and CK-MB increased significantly. Echocardiography showed enlargement of cardiac cavity or abnormal activity of ventricular wall, and/or radionuclide cardiac function examination confirmed that left ventricular systolic or diastolic function was weakened.
Four. Pathogenic basis
1. Detect virus, virus gene fragment or virus protein antigen from acute endocardium, myocardium, pericardium or pericardiocentesis fluid.
2. Virus antibody: the titer of isotype virus antibody (such as Coxsackie B virus neutralizing antibody or influenza virus hemagglutination inhibition antibody, etc.). ) in the second serum is 4 times higher than that in the first serum (the interval between two sera should be more than 2 weeks), or the antibody titer of the first serum is ≥ 640,320, which is suspected to be positive (if it is pressed 1: 32, it should be ≥ 256,660).
3. The virus-specific IgM:≥ 1∶320 is positive (under strict quality control conditions according to the diagnostic standards of various laboratories). If there is enterovirus nucleic acid positive in the blood at the same time, it is more supportive to have a recent virus infection.
If any two of the above (1.2.3) and (3) exist at the same time, it can be clinically diagnosed as acute viral myocarditis after excluding other causes of myocardial diseases. If there are 1 items in the fourth middle school, acute viral myocarditis can be diagnosed from the etiology; If you only have 2.3 items in Grade 4, you can only be diagnosed as acute viral myocarditis in etiology.
If the patient has one or more manifestations such as Asperger's syndrome, congestive heart failure with or without myocardial infarction-like ECG changes, cardiogenic shock, acute renal failure, persistent ventricular tachycardia with hypotension or myocardial pericarditis, it can be diagnosed as severe viral myocarditis. It is not easy to diagnose acute viral myocarditis if only a few premature beats or mild T wave changes occur within 3 weeks after virus infection.
Those who are difficult to make a definite diagnosis can be followed up for a long time, and endocardial myocardial biopsy can be done for virus gene detection and pathological examination when conditions permit.
When considering the diagnosis of viral myocarditis, we should exclude diseases that affect the myocardium, such as beta receptor hyperactivity, hyperthyroidism and mitral valve prolapse syndrome, such as rheumatic myocarditis, toxic myocarditis, coronary heart disease, connective tissue disease, metabolic disease and Keshan disease (Keshan disease area).
Opinions of WHO /ISFC Working Group on the Definition and Classification of Cardiomyopathy
The report of WHO /ISFC working group on the definition and classification of cardiomyopathy was published in Circulation (1996), Volume 93, Page 84 1 ~ 842. In order to facilitate the adoption and application of cardiovascular disease clinicians in China, the translation is reproduced below.
Disease classification is a bridge between unknown causes and known causes. Cardiomyopathy was previously defined as "unknown myocardial disease" to distinguish it from specific myocardial diseases with known causes. With the deepening understanding of etiology and pathogenesis, the difference between cardiomyopathy and specific myocardial diseases has become unclear. Because the original type III cardiomyopathy has been widely accepted and applied in clinic, the name is still retained. At present, cardiomyopathy is classified according to the main pathophysiology or etiology (if possible).
Definition and classification
Cardiomyopathy refers to myocardial disease with cardiac insufficiency. It can be divided into dilated cardiomyopathy, hypertrophic cardiomyopathy, restrictive cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy.
Dilated cardiomyopathy is characterized by left ventricular or biventricular dilatation and impaired systolic function. It can be idiopathic, familial/hereditary, viral and/or immune, alcoholic/toxic, or accompanied by known cardiovascular diseases, but the degree of myocardial dysfunction cannot be explained by the degree of abnormal load or myocardial ischemic injury (see below). Histological examination is not specific. It is often manifested as progressive heart failure, arrhythmia, thromboembolism and sudden death, which can occur at any stage.
Hypertrophic cardiomyopathy is characterized by left ventricular and/or right ventricular hypertrophy, often asymmetric hypertrophy, involving interventricular septum. Usually, the left ventricular volume is normal or reduced, and there is often a systolic pressure gradient. Most people with family history have autosomal dominant inheritance, and filament contraction protein gene mutation can cause disease. Typical morphological changes include hypertrophy and disorder of myocardial cells and increase of loose connective tissue in surrounding areas. Arrhythmia and premature death often occur.
Restrictive cardiomyopathy is characterized by unilateral or bilateral ventricular filling restriction and diastolic volume reduction, but systolic function and ventricular wall thickness are normal or close to normal. Interstitial fibrosis may increase. It can be idiopathic or accompanied by other diseases (amyloidosis, endocardial myocardial disease with or without eosinophilia, etc. ).
Arrhythmogenic right ventricular cardiomyopathy refers to the gradual replacement of normal right ventricular myocardium by fibrous adipose tissue. The early stage is typical regional, and the late stage can involve the whole right ventricle or even part of the left ventricle, with relatively few interventricular septa. Familial diseases are common, which are autosomal dominant, incomplete dominant and recessive. Arrhythmia and sudden death are common, especially in young patients.
Amorphous cardiomyopathy includes some cardiomyopathy (such as fibroelastofibromatosis, non-dense cardiomyopathy, systolic insufficiency but only mild ventricular dilatation, mitochondrial diseases, etc.) that do not completely meet any of the above groups. ). Some patients may show more than one clinical manifestation of cardiomyopathy (such as amyloidosis and systemic hypertension). It has been recognized that arrhythmia and conduction system diseases may be primary myocardial abnormalities, but they have not been included in the category of cardiomyopathy.
Specific cardiomyopathy
Refers to myocardial diseases accompanied by specific heart diseases or specific systemic diseases. It was once defined as a specific myocardial disease.
Ischemic cardiomyopathy is similar to dilated cardiomyopathy, and its impaired systolic function cannot be explained by the degree of coronary artery disease or ischemic injury.
Valve cardiomyopathy is characterized by ventricular dysfunction inconsistent with abnormal load state.
Hypertensive cardiomyopathy is characterized by left ventricular hypertrophy, with dilated or restrictive cardiomyopathy and heart failure.
Inflammatory cardiomyopathy with myocarditis and cardiac insufficiency. Myocarditis is an inflammatory disease of myocardium. At present, there are diagnostic criteria of histology, immunology and immunohistochemistry. It can be caused by idiopathic, autoimmune and infectious diseases. Inflammatory myocardial disease is also related to the pathogenesis of dilated cardiomyopathy and other cardiomyopathy such as Chagas disease, HIV, enterovirus, adenovirus and cytomegalovirus infectious cardiomyopathy.
Metabolic cardiomyopathy includes endocrine: toxic goiter, hypothyroidism, adrenocortical insufficiency, pheochromocytoma, acromegaly and diabetes; Familial cumulative or invasive diseases: for example, hemochromatosis, glycogen storage disease, Heller's syndrome, Rafsum's syndrome, Niemann-Pick's disease, Han-Shu disease, Fa-Anderson disease, Morchio-Ullrich disease; Nutritional deficiency: such as abnormal potassium metabolism, magnesium deficiency and nutritional abnormality (such as malnutrition, anemia, beriberi and selenium deficiency); Amyloidosis: primary, secondary, familial and hereditary cardiac amyloidosis; Familial Mediterranean fever and senile amyloidosis.
Systemic diseases include connective tissue diseases, such as systemic lupus erythematosus, polyarteritis nodosa, rheumatoid arthritis, scleroderma and dermatomyositis. Invasive and granulomatous diseases include sarcoidosis and leukemia.
Muscle atrophy includes Duchenne, Baker and myotonic atrophy.
Neuromuscular diseases include Friedrich's ataxia, Noonan syndrome and pigmented diseases.
Allergy and toxic reactions include reactions to alcohol, catecholamines, anthracyclines, radiation and other injuries. Alcoholic cardiomyopathy can have a lot of drinking history, but it is not clear whether the influence of alcohol is pathogenic or only conditional.
Perinatal cardiomyopathy refers to cardiomyopathy that first occurs in the perinatal period, which may be a mixed group of diseases.
The expert group of this seminar thinks that the definition and classification of cardiomyopathy in China can be adopted by WHO /ISFC in general, but considering the current situation in China, the naming of hypertensive cardiomyopathy and inflammatory cardiomyopathy in specific cardiomyopathy will not be adopted for the time being.
In recent years, cardiomyopathy caused by tachyarrhythmia has attracted people's attention, but it is not within this classification and should be paid attention to in clinic.
Yang Yingzhen finishing
Jury members (in order of surname strokes): Ma Yujinde, Li Chenyang, Ji Nan, Ye Rong Gao Runlin, Gu Fusheng, Pu Shouyue, Guo Linni, Jiang Wenping, Gong Lansheng, Dai Yuhua and Dai Guizhu.
Correspondent: Yang Yingzhen, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital affiliated to Shanghai Medical University, 200032.
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