Diagnosis of Arrhythmias (Heart Rhythm Disturbances)
by Ricker Polsdorfer, MD
Arrhythmias may be identified during routine health check-ups, during testing after symptoms have appeared, or during an evaluation of heart health.
The most common method of checking the heart's electrical activity is with an ECG. A healthy heart with normal rhythms will create a specific pattern on the ECG. Abnormal rhythms of the heart will change the appearance of this pattern. Changes in certain areas of the ECG pattern will also show what specific areas of the heart are affected or damaged.
Some arrhythmias may only appear when the heart is working hard. An exercise stress test is an ECG during physical activity. The test is used to look for an appropriate response to exercise, appearance of abnormal rhythms or events during activity, and ability for heart to recover after activity. People who cannot exercise may be given IV medication that simulates the effects of physical exertion on the heart.
Most arrhythmias are not constant. They may not occur during testing in a care center. Your doctor may recommend a portable device that will monitor your heart rhythm over a long period of time during everyday activities. Portable heart monitoring can be done with:
Tests to Look for Causes
If you are diagnosed with an arrhythmia, your doctor may want other tests to help determine if there is an underlying cause. This may include imaging tests, which can evaluate your heart, blood vessels, and surrounding structures for any loss of function or damage. Imaging tests may include:
Other tests to look for potential causes or contributing factors include:
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Last reviewed June 2017 by EBSCO Medical Review Board Michael J. Fucci, DO, FACC
Last Updated: 12/20/2014
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