What type of data is measured by an electrocardiogram (ECG)?

An electrocardiogram (ECG) measures the electrical activity of the heart. This electrical activity reflects the heart's rhythm and function, providing crucial information about how well the heart is working. Each heartbeat is triggered by electrical impulses that travel through the heart muscle, causing it to contract and pump blood. The ECG records these impulses over time, allowing healthcare providers to detect abnormalities in heart rhythm, identify issues such as arrhythmias, and assess the overall health of the heart.

In contrast, blood pressure readings, body temperature variations, and respiratory rates are not related to the electrical functioning of the heart. Blood pressure readings assess the force of blood against the artery walls, body temperature variations indicate thermoregulation, and respiratory rates measure the number of breaths taken in a given time period. Each of these measures reflects different physiological parameters and is assessed using different tools and methods, highlighting the specific purpose of an ECG in monitoring heart health.