A Holter or event monitor may show what's causing symptoms of an arrhythmia. An arrhythmia is a problem with the rate or rhythm of the heartbeat.
A Holter or event monitor also can show whether a heart rhythm problem is harmless or requires treatment. The monitor might alert your doctor to medical conditions that can result in heart failure, stroke, or sudden cardiac arrest.
If the symptoms of a heart rhythm problem occur often, a Holter or event monitor has a good chance of recording them. You may not have symptoms while using a monitor. Even so, your doctor can learn more about your heart rhythm from the test results.
Sometimes Holter and event monitors can't help doctors diagnose heart rhythm problems. If this happens, talk with your doctor about other steps you can take.
One option might be to try a different type of monitor. Wireless Holter monitors and implantable loop recorders have longer recording periods. This may allow your doctor to get the data he or she needs to make a diagnosis.