What does an electrocardiogram (ECG) record?

What does an electrocardiogram (ECG) record?

• A. Gait analysis
• B. Electrical impulses of the heart
• C. Blood pressure
• D. Pulse rate

Answer: (B)

An ECG records the heart’s electrical impulses as they travel through the conduction system and coordinate the heartbeat. This electrical activity triggers the heart muscles to contract, and the tracing shows distinct waves—the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization). By analyzing the rhythm and rate on the tracing, clinicians can detect arrhythmias, blocks, and other conduction problems, and estimate heart rate. It does not measure gait, blood pressure, or the pulse directly—those are assessed by other methods. The ECG’s value lies in mapping the electrical activity that drives the heart’s mechanical action.

An ECG records the heart’s electrical impulses as they travel through the conduction system and coordinate the heartbeat. This electrical activity triggers the heart muscles to contract, and the tracing shows distinct waves—the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization). By analyzing the rhythm and rate on the tracing, clinicians can detect arrhythmias, blocks, and other conduction problems, and estimate heart rate. It does not measure gait, blood pressure, or the pulse directly—those are assessed by other methods. The ECG’s value lies in mapping the electrical activity that drives the heart’s mechanical action.