Limb lead hypovoltage is manifested on the ECG as QRS wave voltage less than 0.5 mV in 6 leads of the limb. It can be seen in patients with acute myocardial infarction, as well as in patients with severe cardiomyopathy, myocarditis, pericardial effusion, massive pleural effusion, and emphysema; it can also be seen in normal people, and episodes are more common in older patients. Most normal people can be managed without special management and only require regular follow-up. Some patients have previous severe cardiomyopathy, acute myocardial infarction, and this condition can be treated according to the primary cause. If the patient has constrictive pericarditis, pericardial effusion, etc., the primary disease also needs to be treated.