Final answer:
Electrocardiograms (ECGs) provide valuable information about the heart, including detecting damaged heart tissue and tracking changes in heart function over time. Portable ECG monitors can be used outside of medical facilities.
Step-by-step explanation:
Electrocardiograms (ECGs) provide a wealth of information about the heart. The 12 leads of a state-of-the-art ECG can detect regions of damaged heart tissue, known as infarcts, and subtle changes due to heart damage. ECGs can also help in comparing a recent ECG to an older one to track changes in heart function over time. Additionally, ECG technology has advanced to the point where portable ECG monitors can be used in patients' homes or emergency vehicles.