Which test is typically used to evaluate cardiac arrhythmias?

• A. Radiography
• B. Electrocardiogram
• C. Doppler ultrasonography
• D. Nerve conduction velocity testing

Answer: (B)

Detecting arrhythmias requires measuring the heart’s electrical activity as it happens. The electrocardiogram records the electrical impulses that coordinate each heartbeat, producing a tracing that shows heart rate, rhythm, conduction intervals, and abnormalities in the sequence of beats. By examining features such as the P waves, QRS complexes, T waves, and timing, clinicians can identify arrhythmias like atrial fibrillation, flutter, bradycardia, tachycardia, and blocks. It’s quick, noninvasive, and can be done at rest or during activity to catch dynamic changes.

Radiography reveals anatomy and heart size, not rhythm. Doppler ultrasonography assesses blood flow and valve function rather than the electrical activity underlying rhythm disturbances. Nerve conduction velocity testing evaluates peripheral nerves, not cardiac electrical activity. Therefore, the electrocardiogram is the typical test used to evaluate cardiac arrhythmias.