What diagnostic tool is frequently used to confirm atrial fibrillation?

The electrocardiogram (ECG) is the primary diagnostic tool used to confirm atrial fibrillation. This test records the electrical activity of the heart and is crucial for identifying the characteristic irregular and often rapid heart rhythms associated with atrial fibrillation. During an ECG, the specific waveforms and intervals are analyzed, revealing the distinct arrhythmic pattern that indicates the presence of atrial fibrillation.

In contrast, while a chest X-ray can provide visual information about the heart's size and any pulmonary issues, it does not directly show the electrical activity necessary to diagnose arrhythmias. An echocardiogram offers an assessment of heart structure and function, which can be useful for evaluating potential complications but cannot confirm atrial fibrillation on its own. Blood tests can help rule out other conditions or assess risk factors but do not provide information about the heart rhythm directly.