Tests for Arrhythmia
An arrhythmia is an abnormal heartbeat. A person with
arrhythmia can have a faster than normal, slower than normal, or irregular
heartbeat. Because the heart has to work harder than normal to maintain a
constant supply of blood to the body, people with arrhythmias may feel faint,
dizzy, or lightheaded. In severe cases, an arrhythmia can cause cardiac arrest.
If you have these symptoms, your doctor may perform some
tests to determine if you have an arrhythmia.
One of the most common tests that a doctor orders to get an
idea of how your heart beats is an electrocardiogram (ECG). In this test,
electrodes or patches are attached to different places on your chest, arms, and
legs. The patches will record the heart’s activity and draw a picture of the
different waves in your heartbeat. You doctor will look at this pattern and use
it to determine if you have a heart problem. This test doesn’t last long, and it
Event Monitors and Devices
Sometimes arrhythmias happen at unpredictable times. This
means that it can be difficult to capture with an ECG. When this is the case,
it is necessary to monitor the heart over a long period. There are three types
of monitors that can be used at home to monitor the heart.
A Holter monitor records the heart’s activity over 24 to 48 hours.
Like the ECG, you will attach electrodes or patches to areas on your body and
the monitor can record the overall picture of your heart’s activity.
Event monitors, or loop recorders, can be used over one to
two months by patients that have less frequent symptoms and can’t get to a
doctor in time to record them. This monitor uses clips or bracelets that you
attach to your skin whenever you experience symptoms (dizziness, fainting).
Your heart’s activity is recorded, and the information is stored in the
recorder for your doctor to analyze later. It is a portable device that you can
carry with you.
This device is like an event
monitor. It records your heart’s activity, but it’s implanted under the skin.
You or your doctor can program it to record when an event happens, or you can
trigger the device to record by using a remote.
There are several other tests that your doctor may order to
determine the type or cause of an arrhythmia.
The stress test is a fairly common test doctors use to see
how the heart performs under stress or exercise. For diagnosing arrhythmias,
this is used to see if an abnormal heartbeat is related to exercise. The doctor
will attach electrodes to you as with an ECG, and then you will run on a
treadmill or pedal strenuously on a stationary bicycle for a period of time.
This test is used for people who faint often. During this
test, you will lie on a table and the doctor will record your heart rate and
blood pressure while you are lying flat, and then as the position of the table
changes. The doctor may also give you medication through an IV to see how your
heart responds during certain conditions. The test usually
takes around 60 minutes.
Electrical Physiological Studies
This is an invasive procedure useful for diagnosing certain types of
arrhythmias in patients who have had heart attacks or in patients who have a fast
heart rate (tachycardia). The doctor will thread thin wire electrodes through a
vein and into the heart in order to study the heart rhythm.
Transthoracic Echocardiography (TTE) and Echocardiograms
In these procedures, the doctor will take a picture of your
heart using sonar waves to see its size, structure, and function. Your doctor
will put gel on an instrument called a transducer, and move this over your
chest to see the areas of your heart.
In addition to monitoring your heart, your doctor may order
blood tests to check the levels of calcium, potassium, magnesium, or other
chemicals that play a role in your heart’s electrical system. Your doctor may
also want to determine your cholesterol levels, as well as the amount of carbon
dioxide in your blood.
Test results will vary depending on the type of test and
arrhythmia the doctor will diagnose. Be sure to discuss the results and the
treatment with your doctor.