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 is painless.
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.
Implantable Loop Recorders
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.