Which diagnostic tool is commonly used to assess heart rhythm and detect arrhythmias?

The Electrocardiogram (ECG or EKG) is the primary diagnostic tool utilized to assess heart rhythm and identify arrhythmias. This tool measures the electrical activity of the heart over a period of time, providing a visual representation of the heart's rhythm and any irregularities. The graphical output allows healthcare providers to detect various forms of arrhythmias, such as atrial fibrillation, ventricular tachycardia, and other conduction problems, by analyzing the patterns and intervals in the waveform.

Unlike other diagnostic tools, the ECG is specifically designed to capture the timing and shape of electrical signals that trigger heartbeats, making it essential for diagnosing conditions related to heart rhythm. Other imaging techniques, such as X-rays, MRIs, and cardiac ultrasounds, serve different purposes, focusing on structural abnormalities or assessing blood flow rather than directly evaluating heart rhythms. Therefore, the ECG stands out as the most appropriate and commonly used tool for this specific assessment.