An electrocardiogram (ECG or EKG) is a diagnostic test that records the electrical activity of the heart over a period of time. It’s a commonly used tool in cardiology to assess the heart’s rhythm, rate, and overall electrical conduction system. During an ECG, small electrodes are placed on the chest, arms, and legs.
These electrodes detect the electrical impulses generated by the heart and transmit them to a machine, which displays the heart’s electrical activity as a series of waves on a graph.
The waves on an ECG represent different phases of the cardiac cycle. The main components include the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization). Each wave provides valuable information about the heart’s function.
Healthcare professionals analyze the ECG tracing to identify any abnormalities. They assess the rhythm, rate, and duration of the various waves to diagnose conditions such as arrhythmias, myocardial infarctions, or heart block. ECGs are used in a variety of clinical settings, including emergency departments, cardiology clinics, and ambulances, and they are essential tools for assessing patients with chest pain, palpitations, syncope (fainting), and other cardiac symptoms.
In addition to standard ECGs, patients may undergo ambulatory monitoring, such as Holter monitoring, which records the heart’s electrical activity over an extended period. This allows for the detection of intermittent arrhythmias that may not be captured during a standard ECG. While ECGs provide valuable information, they have limitations. They may not always detect subtle abnormalities, and false-positive or false-negative results are possible. Additional testing, such as echocardiography or stress testing, may be necessary for a comprehensive evaluation.
Overall, electrocardiography is a fundamental tool in cardiology that allows healthcare professionals to assess the heart’s electrical activity quickly and non-invasively, guiding appropriate management and treatment strategies.
