EKGs

A standard electrocardiogram, commonly abbreviated EKG or ECG, is a noninvasive test that records the electrical activity of the heart over a short period. A standard 12-lead ECG uses surface electrodes placed on the chest, arms, and legs to obtain multiple viewpoints of the heart’s electrical activity. It provides information about heart rate, rhythm, and electrical conduction.

The tracing shows waves and intervals: P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization). Clinicians assess rate, rhythm, PR interval, QRS duration, QT interval, and ST segments to identify abnormalities such as arrhythmias, ischemia, or electrolyte disturbances. The test is a snapshot; it may be normal even in some disease, and abnormalities may be intermittent.

Uses include routine screening, evaluation of chest pain, syncope, palpitations, preoperative assessment, and monitoring during treatment. It complements other tests such as rhythm monitoring (Holter or event monitors) and imaging. Interpretation requires training; there are artifact and lead-placement issues that can affect results.

The procedure is quick and painless, with the patient lying still. Small amounts of gel or adhesive pads are used for skin contact. Modern EKGs are recorded digitally and stored for comparison. The term EKG derives from the German ElektroKardiographie, while ECG is the more widely used spelling in many regions.