What is dilated cardiomyopathy? What are the dangers? The so-called dilated cardiomyopathy is not coronary heart disease in the traditional sense, although the occurrence of coronary heart disease accounts for the majority of heart patients today (mainly due to lesions in the large blood vessels of the heart), but dilated cardiomyopathy is different, dilated cardiomyopathy is a lesion of the heart muscle itself rather than the large blood vessels, the morphology of the heart is mainly manifested by the enlargement of the ventricular cavity and the overall reduction of heart function, the patient may show activity Dilated cardiomyopathy can be diagnosed only after other causes of heart enlargement have been excluded. What causes dilated cardiomyopathy? The cause of dilated cardiomyopathy is not very clear so far. Some reports suggest that it is caused by acute or chronic recurrent infections involving the myocardium, so in clinical practice doctors will pay more attention to whether the patient has a longer or more serious history of colds and diarrhea during the course of the enlarged heart disease. Various viral and bacterial infections affect the myocardium, and patients may experience different symptoms such as chest tightness, panic, dizziness, and weakness, and clinically, they manifest as premature beats, heart block or myocardial ischemic manifestations of varying severity. Of course, selenium deficiency is another possible cause. Selenium is a trace element, and dilated cardiomyopathy, also known as Keshan disease, is often found in the early stages, especially in the Keshan region, due to selenium deficiency in patients. For dilated cardiomyopathy, the onset is often insidious, most patients do not have obvious discomfort in the early stages of the disease itself, and often wait until the symptoms of cardiac insufficiency appear and the heart chambers have been significantly enlarged before they come to the clinic, at which time the majority of patients are already difficult to reverse the size of the heart chambers and cardiac function. Is there any characteristic test that can confirm the diagnosis of dilated cardiomyopathy? The diagnosis of dilated cardiomyopathy is not confirmed by physical examination alone, but only by the enlargement of the heart. A complete set of ancillary tests must be done to rule out other diseases causing the enlargement of the heart before the final diagnosis can be made, including cardiac ultrasound to determine whether the heart is enlarged and its function, coronary CT or cardiovascular angiography to rule out myocardial damage caused by coronary artery disease, and, more recently, cardiac magnetic resonance imaging at specialized heart centers. In recent times, there are also cardiac MRI examinations at specialized cardiac centers to determine whether there is enlargement of the heart caused by left ventricular densification or nodal disease, and to identify what is dilated cardiomyopathy and what is not, and then to provide different treatments for different causes. Can the diagnosis be confirmed by cardiac ultrasound? What does a low EF mean? Cardiac ultrasound does not definitively identify dilated cardiomyopathy, but it can be used as a non-invasive tool to provide quick and easy information about the size, structure and function of the heart. When the cardiac ultrasound indicates a general decrease in ventricular systole with a significantly lower than normal LVEF, it means that the patient’s heart function is significantly diminished, and the degree of diminution is directly proportional to the severity of the disease, on the basis of which the doctor knows that the patient has a serious heart problem and will then screen the patient further. What is the significance of the x-ray findings? The value of X-rays in the diagnosis of dilated cardiomyopathy has declined, as both physical examination and cardiac ultrasound can provide timely and accurate information about the size of the heart, and X-rays are unreliable in diagnosing “enlarged heart shadow” and do not provide information about the function of the heart. The only additional information an X-ray can provide is whether there is inflammation in the patient’s chest, which may be a cause of aggravation of the patient’s recent symptoms. The role of X-rays in the diagnosis of dilated cardiomyopathy has been diminishing due to their radiographic and resolution properties. Can an endomyocardial puncture biopsy conclusively confirm the diagnosis? Is it more accurate than other tests? Is it necessary for all patients? Endomyocardial biopsy has some value as a diagnosis of dilated cardiomyopathy, but it is not necessary because its histological manifestations are not specific. We know from the definition of dilated cardiomyopathy that any heart enlargement and cardiac malfunction without other causes can be called dilated cardiomyopathy. From what is seen on biopsy, first of all, in the biopsy tissue of dilated cardiomyopathy, cardiomyocytes are seen to be hypertrophic and variable in size, with myocardial fibrosis and myocardial cell necrosis; however, it is worth noting that not all patients need biopsy, which is an invasive operation with certain risks, especially when the patient has reduced cardiac function and thin myocardial wall risk versus benefit is the first issue to be considered In addition, the number of sites that can be biopsied is very limited, and the amount of tissue taken for biopsy is very small, so there is always the possibility that the diseased tissue is not taken. Accordingly, technology now offers a simpler and more effective method. We can use the latest cardiac magnetic resonance technology to non-invasively observe whether there is acute inflammatory edema, myocardial thickness and cardiac function in the whole heart without hospitalization; more ideally, we can clearly see whether there is myocardial necrosis and fibrosis in different parts of the heart through magnetic resonance, which can be described as “non-invasive tissue biopsy”. In our cardiology department, we have detected a group of patients diagnosed with dilated cardiomyopathy by cardiac MRI, and used it to screen for cardiomyopathic causes of heart enlargement. We found that some of these patients actually had enlarged hearts caused by other causes such as hypertrophic dilated cardiomyopathy, left ventricular densification insufficiency, nodal disease, etc. The treatment of these patients and their response to different treatments are closely related to the causes, and therefore may change the entire subsequent treatment strategy and the patient’s prognosis. Can patients with milder symptoms be left untreated? In patients with mild symptoms but already enlarged heart or even decompensated heart function, treatment should never be stopped. In case of acute myocardial dilatation caused by transient infection, we should prevent recurrent infections to avoid another cardiac dilatation; in patients with already chronic lesions, appropriate drugs should be applied for a long time to slow down the process of cardiac dilatation. Once the degree of dilatation and cardiac function has decreased to a certain level, cardiac resynchronization therapy or cardiac decompensation are the means to be considered.