EKG (Electrocardiogram)

What it is

Every heartbeat starts as an electrical impulse that spreads through the heart muscle in a fixed sequence. Electrodes on the skin pick that signal up from several directions at once, and the machine plots each direction as a separate trace. A doctor reading those traces can tell how fast the heart is going, whether the rhythm is regular, whether the signal is being delayed or blocked somewhere, and whether part of the muscle is short of blood or has been damaged in the past. This code is the complete study: the recording is made and a physician interprets it and writes a report. The same test can be split for billing, with one charge for producing the tracing and another for the reading — which is why an EKG sometimes appears twice on a statement under different codes.

Why it is done

• To investigate chest pain, palpitations, breathlessness, or fainting
• To check the rhythm when the pulse is irregular, too fast, or too slow
• To look for signs of a heart attack, either happening now or in the past
• To monitor the effect of a heart medication, or of a condition known to strain the heart
• As a baseline before surgery or before starting certain drugs

What to expect

There is no preparation and nothing to swallow or inject. Patients undress to the waist, lie flat, and the technician cleans small patches of skin — shaving a little chest hair if needed — before sticking on the electrodes and clipping the leads to them. The recording takes seconds, during which lying still and breathing normally matters, because movement blurs the trace. The electrodes come off immediately afterwards. It is painless and no current enters the body; the machine only listens. A doctor reads the result, sometimes within minutes in an emergency setting and sometimes later that day in a clinic.

Questions worth asking

• Is the tracing and the interpretation billed as one item here, or as two separate charges from the facility and a reading physician?
• Was this EKG done in an emergency department or urgent care? The test itself is inexpensive, but the visit around it usually is not.
• If it was ordered before surgery, is the pre-operative EKG covered under my plan, and is it billed by the hospital or by the surgeon's office?
• If the result was normal and is being repeated at a later visit, what changed to make the repeat necessary?