As far as is known the cause are as follows: 1. Infection immune response that cardiac disease is a virus infection after the myocardial damage caused by immune. This is the basis for support for: ① many cardiac patients in the original onset healthy or suffering from diarrhea after respiratory infections; ② cardiac patients in cardiac immunoglobulin increased; ③ myocardial inflammatory pathological examination in the performance, such as interstitial fibrosis with lymphatic or monocyte infiltration; ④ cardiac patients have T-cell function suppression of evidence, suggesting that their immune response is there; ⑤ some cardiac patients natural killer cell function; ⑥ individual cardiac patients, especially early in the course of patients with hormone therapy effective; ⑦ cardiac patients with blood in the Coxsackie B virus and antibody is higher than normal. Now that violations of myocardial Coxsackie B virus, the virus early in the proliferation of cardiac cells and cause myocardial necrosis, this time using immunosuppressive drugs harmful. The second phase, the virus can no longer myocardial find, but there are more thymus source of T-lymphocytes, such sensitized cells to cardiac cells, immune from pathological muscle necrosis. Lymphocyte infiltration and myocardial necrosis can be found in any cavity, may be left ventricular cavity of the high pressure involved more. The latter part of the inflammatory cell infiltration reduced or disappeared, the lesions become fibrosis, and myocardial hypertrophy in or out of the cells are intertwined, this stage is dilated cardiomyopathy in the composition stage. In addition to the typical process, some cardiac patients lack of evidence of infection, when interpreted as a viral infection spread to the heart despite, but not obvious symptoms but not the attention, after cardiac diseases and potential for continuous development of signs and symptoms appear by Xi . Therefore, it can be considered part of the patient is the chronic stage of myocarditis or sequelae, but it is difficult at this time myocardial virus or isolated by fluorescence immunoassay find specific antigen, and the infection can not be sure of the cause and effect relationship. - Infected immune response in the present, though a doctrine of dilated cardiomyopathy incidence of major doctrines, but there are many areas and issues not yet clear, pending further study. 2. Myocardial of the small branches of the coronary artery disease, caused cramps and obstruction, but failed to confirm widespread. 3. Some cases of myocardial metabolism of certain enzymes, such as the lack of succinate dehydrogenase, but this may be the consequences of failure mechanism rather than the first. 4. Some cases and nutrition-related obstacles, such as the lack of selenium in the diet may cause cardiac changes, but not all cases are selenium deficiency.
