The electrocardiographic manifestations of old inferior myocardial infarction are mainly the following: First, pathological Q waves may appear on the electrocardiogram, such as Q wave formation in leads II and III, and also in the avF leads of the electrocardiogram. The second is the presence of ST-segment depression or elevation. In some patients with inferior ventricular wall tumors, the ST-segment may remain elevated and may not return to its ultimate level. In some patients, the ST segment may remain elevated and not return to its ultimate level. Some patients may show a downward shift or depression of the ST segment. Thirdly, there are changes in the T waves in the inferior wall leads, leads II, III, avF, or in some patients, low frequency or inversion of the T waves in leads I and avR. However, the most specific one is the first one, which is the presence of pathological Q waves in the inferior wall leads.