Jun 21 2011 11:56 AM

Holter/Event-Recorder

Postevent Recorders

Postevent recorders are among the smallest event monitors. You can wear a postevent recorder like a wristwatch or carry it in your pocket. The pocket version is about the size of a thick credit card. These recorders don't have wires that connect the device to chest sensors.

When you feel a symptom, you start the recorder. A postevent recorder only records what happens after you start it. It may miss a heart rhythm problem that occurs before and during the onset of symptoms. Also, it may be hard to start the monitor when a symptom is in progress.

In some cases, this missing data would have helped your doctor diagnose the heart rhythm problem.

Presymptom Memory Loop Recorders

Presymptom memory loop recorders are the size of a small cell phone. They're also called continuous loop event recorders.

You can clip this event monitor to your belt or carry it in your pocket. Wires connect the device to sensors on your chest.

These recorders are always recording and erasing data. When you feel a symptom, you push a button on the device. The normal erase process stops. The recording will show a few minutes of the data from before, during, and after the symptom.

In some cases, this makes it possible for your doctor to see very brief changes in your heart's rhythm.

Autodetect Recorders

Autodetect recorders are about the size of the palm of your hand. Wires connect the device to sensors on your chest.

You don't need to start an autodetect recorder during symptoms. These recorders detect abnormal heart rhythms and automatically record and send the data to your doctor's office.

Implantable Loop Recorders

You may need an implantable loop recorder if other event monitors can't provide enough data. Implantable loop recorders are about the size of a pack of gum. This type of event monitor is inserted under the skin on your chest. No wires or chest sensors are used.

The device records either when you activate it or automatically when symptoms occur. It depends on how your doctor programs it. Devices may differ, so your doctor will tell you how to use it. In some cases, a special card is held close to the recorder to start it.

What Does a Holter or Event Monitor Show?

A Holter or event monitor may show what’s causing symptoms of an arrhythmia. This is problem with the speed or rhythm of the heartbeat.

Holter and event monitors also can show whether a heart rhythm problem is harmless or whether it needs treatment. Treatment is needed if the problem causes serious symptoms or increases your chance for complications.

Serious symptoms may include dizziness, chest pain, and fainting. Complications may include heart failure, stroke, or sudden cardiac arrest.

If the symptoms of your heart rhythm problem occur often, a Holter or event monitor has a good chance of capturing them. You may not have symptoms while using a monitor. Even so, your doctor may learn more about your heart rhythm from the test results.

Sometimes, these monitors can’t help doctors diagnose heart rhythm problems. If this happens, talk to your doctor about other steps you can take.