Atrial fibrillation, abbreviated as AF, refers to rapid and irregular beating of the atrial chambers of the heart. How should one be examined after being diagnosed with atrial fibrillation? Generally, the examination for atrial fibrillation involves the following aspects: First, blood tests, such as thyroid function tests, to see if there is hyperthyroidism causing the atrial fibrillation. Second, echocardiography. This test can reveal whether there are any heart valve diseases or myocardial diseases that might lead to atrial fibrillation. Third, electrocardiogram (ECG) and Holter monitor. Both ECG and Holter monitoring are effective and non-invasive tests that confirm the diagnosis of atrial fibrillation.