Electrocardiogram:A recording of the electrical activity of the heart. Abbreviated ECG and EKG. AnECGis a simple, noninvasive procedure. Electrodes are placed on theskinof thechestand connectedina specific order to a machine that, when turned on, measures electrical activity all over the heart. Output usually appears on a long scroll of paper that displays a printed graph of activity on a computer screen. The initialdiagnosisof heart attack is usually made through observation of a combination ofclinicalsymptoms and characteristic ECG changes. An ECG can detect areas ofmuscledeprived ofoxygenand/or deadtissuein the heart. If amedicationis known to sometimes adverselyaffectheart function, abaselineECG may be ordered before thepatientstarts taking the medicine, and follow-up testing may occur at regular intervals to look for any changes.
