Idioventricular Rhythm

What is idioventricular rhythm?

Idioventricular rhythm is a heart rhythm in which your lower heart chambers beat more slowly than normal. With this type of rhythm, your heart’s ventricles or lower chambers may start your heartbeat if your natural pacemaker located in the upper chambers is unable to pace the heart.

Unlike ventricular tachycardia, which is faster than 100 beats a minute, idioventricular rhythm is less than 50 beats per minute. An accelerated idioventricular rhythm has a rate of 50 to 110 beats per minute.

Idioventricular rhythm vs. junctional

Both of these rhythms start in the wrong part of your heart, but they’re in different places.

Idioventricular rhythm starts in your ventricles or lower chambers. Junctional rhythm begins at the junction of your upper and lower heart chambers.

Who does idioventricular rhythm affect?

Idioventricular rhythm can affect people who:

• Have advanced or complete heart block.
• Have sinus arrest or sinoatrial nodal block.
• Have a heart attack.
• Use certain medications and illegal drugs.
• Have a congenital (present at birth) heart problem (rare).

Although athletes and others without heart disease can get accelerated idioventricular rhythm, many people with this abnormal rhythm may also have:

• Ischemic cardiomyopathy (ICM).
• Rheumatic heart disease.
• Dilated cardiomyopathy.
• Acute coronary syndromes.
• Acute myocarditis.

What are the symptoms?

Usually, people with idioventricular rhythm don’t have any symptoms. If they do, they include:

• Fatigue.
• Dizziness
• Passing out.
• Heart palpitations.

What causes idioventricular rhythm?

Causes of accelerated idioventricular rhythm include:

• Myocarditis.
• Heart attack.
• Some cardiomyopathies.
• Resuscitation.
• High level of potassium, an electrolyte.
• Toxicity from too much digoxin (Digitek® or Cardoxin®).

How is idioventricular rhythm diagnosed?

Your healthcare provider will do a physical exam and ask you about your medical history and your family’s medical history.

They may use these tests to find out if you have idioventricular rhythm:

• Holter monitor.
• Electrocardiogram (EKG) that shows a regular ventricular rhythm but no rhythm in the upper heart chambers.

How is idioventricular rhythm treated?

For most people, idioventricular rhythm is benign (harmless) and you don’t need treatment for it. To treat it, your healthcare provider may take care of the cause, such as:

• Stopping a medicine that caused it.
• Fixing a problem with how your heart works.

What medications or treatments are used?

If the accelerated idioventricular rhythm isn’t going away and your blood pressure drops, your healthcare provider may do one of the following to get your normal rhythm back:

• Give you atropine (Atreza® or Sal-Tropine®) or isoproterenol.
• Use a device to get the rhythm in your upper heart chambers back to normal.

How can I reduce my risk?

Most cases of idioventricular rhythm aren’t harmful, but you may be able to reduce your risk in these ways:

• Exercise and eat heart-healthy foods.
• Keep your electrolytes at a normal level.

What can I expect if I have idioventricular rhythm?

For most people, idioventricular rhythm is harmless and goes away without treatment. However, if you’re fainting and your rhythm isn’t going back to normal, you should get treatment.

When should I seek care?

In most cases, you don’t need to do anything for idioventricular rhythm. It’ll go away by itself. You should contact your healthcare provider if your idioventricular rhythm doesn’t go away on its own and you have a fainting spell.

Call 911 if you think you could be having a heart attack.

What questions should I ask my doctor?

• Do you know the cause of my idioventricular rhythm?
• If I need treatment for idioventricular rhythm, what’s the best treatment for me?

A note from Cleveland Clinic

Although idioventricular rhythm is usually not a cause for concern, other types of abnormal heart rhythms are. If you have heart palpitations and get lightheaded, check with your provider right away. If your treatment involves starting or stopping medication, be sure to follow your provider’s instructions. It’s also important to go to all of your follow-up appointments.