Common causes of heart failure include coronary artery disease including a previous myocardial infarction (heart attack), high blood pressure, atrial fibrillation, valvular heart disease, excess alcohol use, infection, and cardiomyopathy of an unknown cause.
These cause heart failure by changing either the structure or the functioning of the heart. The severity of disease is graded by the severity of symptoms with exercise.
Heart failure is not the same as myocardial infarction (in which part of the heart muscle dies) or cardiac arrest (in which blood flow stops altogether). Other diseases that may have symptoms similar to heart failure include obesity, kidney failure, liver problems, anemia, and thyroid disease. Heart failure is diagnosed based on the history of the symptoms and a physical examination, with confirmation by echocardiography.
Blood tests, electrocardiography, and chest radiography may be useful to determine the underlying cause