Cardiovascular damage in acquired immunodeficiency syndrome
Introduction
Introduction to cardiovascular damage in acquired immunodeficiency syndrome Acquired immunodeficiency syndrome (AIDS) is a serious infectious disease caused by human immunodeficiency virus (HIV). basic knowledge Sickness ratio: 0.0001% Susceptible people: no specific population Mode of transmission: sexual contact, spread of blood, mother-to-child transmission Complications: arrhythmia heart failure sudden death aneurysm myocardial infarction
Cause
Causes of cardiovascular damage in acquired immunodeficiency syndrome
(1) Causes of the disease
There are two types of HIV: HIV-1 (HIV-1) and HIV-2 (HIV-2). There are three ways to spread AIDS:
1. Sexual contact.
2. Blood, blood products, organ transplants and contaminated syringes.
3. Mother and baby vertical transmission.
The main cause of HIV infection is the failure of the T lymphocyte subset T4. The envelope protein of HIV has a strong affinity with the CD4 antigen on the host cell, and binds to the receptors composed of gp120 and CD4 antigens on the outer membrane. The cell membrane of the host cell is destroyed by the transmembrane protein gp 41, the core part of HIV enters the host cell, and the single-stranded RNA is converted into DNA under the action of reverse transcriptase, and then the DNA is integrated into the host cell by the action of integrase. After long-term incubation in the nucleus, it is recombined into new HIV under the influence of certain factors. Generally, 10% of HIV replicates in cells, and another 90% is latent.
(two) pathogenesis
The main target cell of HIV is CD4+ positive T lymphocytes. The result of massive destruction and functional decline of the latter is that human immune surveillance function is significantly reduced, leading to severe immunodeficiency, opportunistic infections of systemic systems including the cardiovascular system. Tumor.
As far as is known, the mechanism of the decline in the number and function of immune cells has at least the following aspects.
1. The virus causes dissolution damage when part of the CD4+ cells multiply.
2. Free gp120 binds to uninfected CD4+ cells, mediating antibody-dependent cellular cytotoxicity, allowing CD4+ cells to become target cells.
3. HIV can infect bone marrow stem cells, resulting in a decrease in CD4+ cell production.
4. Functional changes in Th1 in helper T cells, which reduce the secretion of IFN-r and IL-2, and Th1 cells act as a vehicle for delayed hypersensitivity reactions, resulting in delayed allergic reactions due to functional damage. Attenuated, IL-4, IL-5, and IL-6 secreted by Th2 also decreased.
5. Th1 attenuates the auxiliary function of B cells.
6. IgG1, IgG3 selectivity increased, while IgG2 and IgG4 decreased, susceptible to Haemophilus, Klebsiella and Staphylococcus aureus.
7. Due to the reduction of lymphokines, the function of NK cells is weakened, and the immune surveillance infection and the function of tumor cells are reduced.
The cause of heart damage caused by AIDS has not been fully elucidated. Since cardiomyocytes do not have CD4 antigen and become less target cells of HIV, it is believed that the heart damage associated with AIDS may be mainly caused by related opportunistic infections or tumor metastasis, but also Some people think that it may be caused by the HIV virus itself and/or by activation of the immune system. Whether the drugs for treating AIDS can cause heart damage is still inconclusive.
Cardiac enlargement is an important manifestation of AIDS heart involvement, mostly biventricular or whole heart enlargement, with dilated cardiomyopathy-like pathological changes; isolated left ventricular or right ventricular dilatation, in which isolated right ventricular dilatation is often accompanied by myocardial Hypertrophy.
Autopsy found that there are many opportunistic infections and malignant tumors in myocardial tissue. The most common pathogens are fungi and viruses, followed by bacterial and protozoal infections, while Kaposi sarcoma and metastatic lymphoma are the most invading myocardium. Common tumors, characteristic histopathological changes of the myocardium mainly include two types: one type shows non-specific inflammatory cell infiltration without myocardial cell necrosis, and the other type only has myocardial cell necrosis without inflammatory cell infiltration. Using immunohistochemistry, cell culture, nucleic acid in situ hybridization and the like, it has been found that there is HIV in or around cardiac muscle cells.
Vascular damage mainly affects small and medium arteries, which are characterized by arterial inflammation and fibrosis. For example, cerebral arteritis can cause AIDS encephalopathy, coronary artery inflammation or aneurysm can cause myocardial infarction.
Prevention
Cardiovascular damage prevention of acquired immunodeficiency syndrome
AIDS has spread to many countries and the main preventive measures are as follows.
1. Strictly ban high-risk groups from donating blood. Those who supply blood must check for the presence or absence of HIV antibodies in their blood. If the serum test is positive, they cannot supply blood.
2. Anti-HBe should be detected when screening blood donors. Because AIDS patients often have hepatitis B infection, this test can eliminate about 90% of blood donors who can transmit AIDS.
3. It is strictly forbidden to import freeze-dried plasma, human albumin, gamma globulin, factor VII and other blood products from abroad.
4. Severe ban on prostitution, concealment, and squatting activities are important measures to prevent the introduction of AIDS; strengthen border health quarantine monitoring and prohibit entry of AIDS patients and infected persons.
5. To strengthen the health management of hotels, restaurants and foreign guests, and do a good job of disinfection.
6. Popularize AIDS knowledge, do a good job in sanitation and disinfection, discourage homosexuality, and prevent drug addicts from spreading the disease through injection.
7. Development of vaccines: There are currently studies dedicated to effective AIDS vaccines, but the variability and polymorphism of this virus has become a major obstacle in vaccine research. It has been confirmed that the envelope protein of HIV produces gp120, which is an immune antigen for neutralizing antibodies. Currently, various AIDS vaccine candidate preparations are mostly composed of gp120 intact polypeptide or partial fragments.
Complication
Cardiovascular damage complications of acquired immunodeficiency syndrome Complications arrhythmia heart failure sudden death aneurysm myocardial infarction
Cardiovascular damage of AIDS can cause heart failure, arrhythmia, embolism, sudden cardiac death and other complications; vascular damage of AIDS mainly involves small and medium arteries, such as cerebral arteritis can cause AIDS encephalopathy, coronary artery inflammation or aneurysm Causes myocardial infarction.
Symptom
Symptoms of Cardiovascular Damage in Acquired Immunodeficiency Syndrome Common Symptoms Weak dyspnea HIV Infection Heart Failure Immune Deficiency Hypertension Heart Failure Dementia Dementia
80% of patients who are infected with HIV do not show clinical symptoms, but they have important epidemiological significance because they can transmit HIV to others. 10% to 20% of patients have 2 to 10 years (average 5 years) Clinical symptoms appear after the incubation period, and the incubation period is related to the dose of HIV infection. The dose of transfusion infection is generally larger, the incubation period is relatively shorter; the dose of sexual contact infection is less, so the incubation period is longer.
Pericardial disease
A large amount of evidence indicates that pericardium is often involved in various pathological conditions associated with AIDS. Although AIDS patients are often asymptomatic due to cardiac involvement, pericardial disease is a common cause of clinical cardiovascular symptoms and signs in AIDS patients. Some studies have confirmed that AIDS patients have pericardium. The incidence of disease is high. 15% to 33% of AIDS patients have excessive pericardial fluid (more than 75ml) at autopsy; 2% to 43% of HIV-infected patients have pericardial effusion during ultrasound examination. Most patients have small fluid accumulation, but there are also many reports of cardiac tamponade. Some people think that the presence of pericardial effusion in HIV-infected patients may indicate the end stage of the disease.
Mainly manifested as pericarditis or (and) pericardial effusion, of which suppurative pericarditis is mostly caused by Staphylococcus aureus, part of Nocardia, Listeria and mycoplasma infection; non-suppurative pericarditis usually by mycobacteria , caused by Cryptococcus neoformans, fungi, etc.; virus infection in addition to HIV, there are still cytomegalovirus, herpes simplex virus and Coxsackie virus, another important reason for pericardial effusion is malignant tumors, such as Kaposi sarcoma, lymph Tumor and adenocarcinoma.
AIDS complicated with pericardial lesions have no obvious clinical symptoms of pericarditis or pericardial effusion, or are often masked by systemic symptoms of AIDS, and its performance is similar to pericarditis caused by other causes, mainly chest pain, difficulty breathing, tachycardia , pericardial friction sound, heart shadow enlargement, blood pressure reduction, pulse pressure reduction and odd pulse, etc., because AIDS patients are mostly dehydrated or extremely depleted, so in the early stage of pericardial tamponade, jugular venous pressure and odd veins and other signs may not be obvious, Etiological evidence is generally not easy to find in pericardial effusions.
Electrocardiogram and chest X-ray examination are similar to non-AIDS-related pericarditis and pericardial effusion. For patients with high suspicion of pericardial AIDS, echocardiography is helpful for early diagnosis and coronary heart disease, hypertensive heart disease, cardiomyopathy Identification with rheumatic heart disease, cardiac computed tomography and magnetic resonance imaging of the heart are also helpful in the diagnosis of pericardial effusion. If necessary, pericardial puncture can be performed. The fluid drawn depends on the cause, mostly serous. It can also be bloody or purulent. In addition, pathogens can be detected in pericardial effusions, but in most cases, the detection or culture of pericardial effusion pathogens is negative.
2. Myocardial disease
AIDS patients with myocarditis are quite common, Anderson et al analyzed 71 cases of AIDS autopsy results, 52% of which have myocarditis, AIDS associated with myocardial lesions are mainly non-specific or infectious myocarditis, and may be caused by cardiomyopathy, which occurs It may be related to the autoimmune reaction after viral infection, other concentric viral infections coexisting with HIV, excessive secretion of catecholamines, cachexia, selenium deficiency, drugs and alcohol for treating AIDS, and cardiotoxic effects such as cocaine or heroin.
Its clinical manifestations are similar to dilated cardiomyopathy, mainly due to congestive heart failure caused by left ventricular systolic and diastolic dysfunction. It may have palpitations, difficulty breathing, coughing, progressive heart enlargement, galloping, and lung mobility. Arpeggios, etc., and various arrhythmias, even cardiac arrest, the difficulty of breathing is easily misdiagnosed as a disease associated with AIDS, but this cardiogenic dyspnea is mostly associated with hypoxemia and The severity of lung disease is disproportionate and helps in identification.
If AIDS patients have heart failure, chest X-ray examination of heart expansion and asymptomatic or unexplained arrhythmia should consider myocarditis, echocardiography can help determine cardiac function and valve, cardiac cavity structure, myocardial radionuclide imaging It is helpful to judge the inflammatory reaction and injury of the myocardium. The endomyocardial biopsy is helpful for diagnosis, and the specimen can be further cultured or applied by DNA probe, in situ hybridization and other molecular biological methods.
3. Endocarditis
AIDS-related endocarditis (caused by suppurative or opportunistic infections) is rare, and intra-venous drug abusers (IVDA) are the second most common risk group for AIDS, but studies have shown that IVDA is not associated with AIDS. The incidence of purulent infection is higher than that of IVDA with AIDS. Even after HIV infection, IVDA is a high-risk group of suppurative infections. Many patients may have suppurative infection before immunodeficiency. In IVDA population, many people At the same time, the abuse of a variety of drugs, such as the simultaneous incidence of intravenous cocaine and heroin endocarditis, in addition, IVDA alcoholics and heroin abusers increased bacterial infection, immune dysfunction may also be related to the abuse of intravenous opium.
Often manifested as non-infectious thrombotic endocarditis, patients with chronic consumption and hypercoagulable state are more common, four valves can be affected, left heart valve involvement is more common, the neoplasm is non-bacterial, Very easy to fall off, mainly composed of platelets, fibrin and very few inflammatory cells, mainly manifested as multiple embolism of the whole body, often involving the brain, spleen, kidney, lung and heart and other organs, and the heart murmur is not obvious.
Infective endocarditis is rare, and most of them are intravenous drug addicts, often part of AIDS and sepsis. The pathogens are mainly Staphylococcus aureus and streptococci, and some are fungi and tuberculosis.
For any HIV-infected person, fever and heart murmur should be suspected as infective endocarditis, routine laboratory tests may have anemia and increased white blood cells; urine sediment tests often have varying degrees of hematuria and proteinuria, because of bacteremia in AIDS patients The symptoms are often quite obvious. In patients with obvious infections, the blood culture is often positive. It is generally considered that the blood culture is sufficient for the initial diagnosis, and the culture-negative endocarditis is rare. The clinically strongly suspected AIDS with endocarditis is Those with negative blood culture may be treated with antibiotics or fungal endocarditis before culture. Anaerobic infection is a culture-negative infection. The positive rate of culture of Candida is less than 50%, and Aspergillus is rare. Cultured, because IVDA often apply antibiotics on their own, blood samples should be taken several days after the first culture to find recurrent infected bacteria, because AIDS patients often have recurrence and multiple microbial infections. Blood culture should be carried out in the later stage of treatment. In order to discover the recurrence of some treated infections or to find previously unsuspected pathogens, echocardiography has important significance in the diagnosis of endocarditis, and found to be a neoplasm. The diagnosis of endocarditis can be established, the false positives are rare, and the sensitivity of echocardiography for the diagnosis of endocarditis is 40% to 90%. No endocarditis can be excluded, and fungal endocarditis is not found. Non-bacterial thrombotic endocarditis has larger neoplasms, and it is easier to find by ultrasound. In addition to the series of clinical evaluations, ultrasound data can help determine surgical treatment and prognosis.
4. Dilated cardiomyopathy
Cardiac enlargement is an important manifestation of heart involvement in AIDS patients. Anderson et al found in autopsy that 17% (12/71) of AIDS patients had enlarged heart, 7 of which were biventricular enlargement, and Himeiman et al applied echocardiography. 11% (8/70) of patients with AIDS complicated with enlarged heart have decreased left ventricular systolic function, 4 of which have congestive heart failure. Many literature reports that AIDS-related dilated cardiomyopathy is associated with myocarditis and myocarditis Similarly, in cardiac anatomy or biopsy of cardiomyopathy, only a few cases can be detected or cultured to pathogens. HIV directly invades the myocardium and autoimmune response is also a possible mechanism leading to cardiomyopathy. In recent years, some cytokines have been proposed by some scholars. Increased levels of tumor necrosis factor, interleukin-1 and interleukin-2, alpha interferon, etc., may cause cardiac insufficiency by local paracrine action on adjacent cardiomyocytes, or impair cardiac function through systemic action Acute or chronic pulmonary hypertension caused by severe, recurrent lung infections (such as Pneumocystis carinii pneumonia), causing right ventricular pressure overload, is isolated Hypertrophy and dilatation of the right ventricle the main reason.
Nutritional factors may also be related to cardiomyopathy. Many AIDS patients have a significant decrease in body weight and cachexia. Animal experiments have shown that when hunger causes malnutrition, myocardial fibers shrink, interstitial edema, accompanied by decreased left ventricular compliance and decreased peak contractility. Congestive heart failure can occur during the process of restoring diet. In addition, there are reports of selenium deficiency in AIDS patients. Decreased myocardial selenium levels can cause heart function decline, and heart function is improved after selenium supplementation, similar to Keshan disease in China.
Similar to non-AIDS dilated cardiomyopathy, mainly characterized by heart enlargement and congestive heart failure, often accompanied by various types of arrhythmias, prone to sudden cardiac death, Danbauchi et al reported 3 cases of AIDS complicated with dilated cardiomyopathy, He was admitted to the hospital with heart failure, of which 2 died and 1 developed multiple organ failure.
AIDS patients with dyspnea performance is not commensurate with the degree of hypoxemia or pulmonary lesions, should consider concomitant cardiac dysfunction, X-ray examination showed increased heart shadow; echocardiography found that each compartment increased, wall motion The general weakening is helpful for diagnosis. The value of endomyocardial biopsy is limited, because the chance of clearing myocarditis by biopsy is very small, and the treatment of focal myocarditis such as glucocorticoids has not proven effective, so less intervention is needed. Sexual cardiovascular diagnosis technology, this disease needs to be differentiated from rheumatic heart disease, hypertension, coronary heart disease and pericardial disease.
5. Heart tumor
Anderson et al found that the incidence of AIDS heart Kaposi's sarcoma was 49% and malignant lymphoma was 1% (1/71).
The main tumors in AIDS patients are Kaposi's sarcoma and non-Hodgkin's lymphoma, especially in the former. Kaposi's sarcoma is derived from endothelial cells, and the heart is often part of the whole body Kaposi's sarcoma. Kaposi's sarcoma of the heart is rare. Kaposi's sarcoma usually mainly invades the epicardium, and may involve the whole layer of the heart. Non-Hodgkin's lymphoma originates from B lymphocytes, and is also metastatic. It is mainly in the lymphocytes of the myocardium. Tumors are rare, and infiltration of tumor cells in the myocardium often leads to congestive heart failure, atrial or ventricular arrhythmia, and conduction block. Tumors that invade the valve or protrude into the ventricle can cause hemodynamic abnormalities. Pericardial effusion.
Cardiac involvement is mainly tumor spread and primary KS (Kaposi's sarcoma), X-ray and clinical manifestations of non-specific heart enlargement, often tachycardia, galloping and heart failure, most patients can die In the cardiogenic shock.
6. Vascular lesions
Vascular lesions of AIDS include arterial lesions, aneurysm formation, vascular endothelial proliferation associated with Kaposi's sarcoma, and coronary thrombosis. Marks et al. studied 28 AIDS patients and found that vascular lesions in AIDS patients were mainly found in the aortic arch and thoracic aorta. , abdominal aorta, femoral artery, superior clavicular artery.
The vascular lesions of AIDS mainly involve small and medium arteries, which are characterized by vasculitis, aneurysm formation, endothelial hyperplasia and thrombosis. The clinical manifestations are affected organ ischemia, necrosis and impaired function.
Examine
Examination of cardiovascular damage in acquired immunodeficiency syndrome
Blood test
White blood cells, hemoglobin decreased.
2. The total number of CD4 lymphocytes is <200/mm3 or 200-500/mm3.
3. CD4/CD8<1.
4. Anti-HIV antibody positive, confirmed by confirmed test.
5. Blood P24 antigen is positive (conditional unit can be checked).
6. The level of 2 microglobulin is increased.
7. The pathogens of the pathogens or tumors of the above various concurrent infections can be found.
8.X line
Chest X-ray examination can help to find signs of pericardial effusion, left and right ventricle enlargement, pulmonary congestion and other signs.
9. Echocardiography
It can provide more intuitive and accurate imaging data for heart enlargement, abnormal cardiac systolic function, pericardial effusion, valvular sputum, cardiac tumor, and lesion at the beginning of coronary artery.
10. ECG
A variety of arrhythmia can be found, including various pre-systolic contractions, tachycardia, conduction block, etc.; ventricular hypertrophy, non-specific ST-T changes, QT interval prolongation, etc. when myocardial involvement; coronary artery obstruction A myocardial infarction pattern appears.
Diagnosis
Diagnosis and diagnosis of cardiovascular damage in acquired immunodeficiency syndrome
Diagnostic criteria
The isolation of HIV from patient tissue is the most specific method for determining HIV infection, but because of the difficulty and sensitivity of virus isolation, one patient has multiple positive anti-HIV tests and confirmed by a confirmatory test (Western blot). HIV infection should be considered. In order to meet the needs of China's AIDS prevention and treatment, China has established a diagnostic standard for HIV/AIDS in 1996. This standard cites the AIDS diagnostic criteria revised by the WHO and the US CDC in 1987, and the classification of HIV infection revised by the US CDC in 1993. And AIDS diagnostic criteria, diagnostic criteria for acute HIV infection, asymptomatic HIV infection and AIDS cases.
Acute HIV infection
(1) History of epidemiology:
A homosexual or heterosexual person has a history of multiple sexual partners, or a spouse or sexual partner is anti-HIV antibody positive.
2 history of intravenous drug use.
3 used imported blood products such as factor VII.
4 Close contact with HIV/AIDS patients.
5 had a history of sexually transmitted diseases such as syphilis, gonorrhea, non-gonococcal urethritis.
6 history abroad.
7 children born to anti-HIV antibodies ( ).
8 Enter blood that has not been tested for anti-HIV.
(2) Clinical manifestations:
1 There are fever, fatigue, sore throat, general malaise and other symptoms of upper respiratory tract infection.
2 Individuals have headache, rash, meningoencephalitis or acute polyneuritis.
3 neck, ankle and occipital with enlarged lymph nodes, similar to infectious mononucleosis.
4 hepatosplenomegaly.
(3) Laboratory inspection:
1 The total number of peripheral white blood cells and lymphocytes decreased after onset, and the total number of lymphocytes increased to show atypical lymphocytes.
2CD4/CD8 ratio >1.
3 anti-HIV antibodies from negative to positive, usually 2 to 3 months before the positive conversion, up to 6 months, antibodies negative in the infection window.
4 a small number of patients with initial blood P24 antigen positive.
2. Asymptomatic HIV infection
(1) Epidemiological history: same as acute HIV infection.
(2) Clinical manifestations: often without any symptoms and signs.
(3) Laboratory inspection:
1 Anti-HIV antibody positive, confirmed by confirmed test.
2 The total number of CD4 lymphocytes was normal, CD4/CD8>1.
3 blood P24 antigen negative.
3.AIDS
(1) Epidemiological history with acute HIV infection.
(2) Clinical manifestations:
1 Unexplained immune function is low.
2 Continued irregular low heat > 1 month.
3 Extending systemic lymphadenopathy with an unexplained cause (lymph node diameter > 1 cm).
4 chronic diarrhea > 4 ~ 5 times / d, weight loss within 3 months > 10%.
5 combined with oral Candida infection, Pneumocystis carinii pneumonia, cytomegalovirus (CMV) infection, toxoplasmosis, cryptococcal meningitis, rapid progress of active tuberculosis, Kaposi sarcoma of the skin mucosa, lymphoma and so on.
6 young and middle-aged patients developed dementia.
(3) Laboratory inspection:
1 Anti-HIV antibody positive confirmed by the confirmed test.
2P24 antigen positive (conditional unit can be checked).
The total number of 3CD4 lymphocytes is <200/mm3 or 200-500/mm3.
4CD4/CD8<1.
5 white blood cells, hemoglobin decreased.
62 microglobulin levels increased.
7 can find the pathogens of the pathogens or tumors of various above-mentioned concurrent infections.
Differential diagnosis
The disease needs to be differentiated from rheumatic heart disease, hypertension, hypertensive heart disease, coronary heart disease, pericardial disease and cardiomyopathy.
