What is the primary purpose of monitoring a patient during an ECG?

Monitoring a patient during an ECG primarily serves to identify heart rhythm abnormalities. An electrocardiogram records the electrical activity of the heart over a period, which provides essential information about how well the heart is functioning and indicates any irregularities in heartbeats or rhythm. The ECG can reveal various conditions such as atrial fibrillation, tachycardia, bradycardia, and other arrhythmias that may require medical intervention or further investigation.

While evaluating physical fitness, assessing lung function, and measuring blood pressure are important aspects of a patient's overall medical evaluation, they are not direct objectives of an ECG. The primary and most critical role of an ECG is its ability to highlight abnormalities in the cardiac rhythm and electrical conduction pathways, which can lead to timely diagnosis and management of cardiovascular issues.