Bradycardia is a slower-than-normal heart rate. The average adult heartbeat at rest is about 60 to 100 beats per minute. In a slow arrhythmia, such as bradycardia, the heart signals do not fire as they should, which causes the heart rate to slow down. Although a heart rate less than 60 is considered bradycardia, a slow heart rate is not necessarily a sign of an abnormal electrical system.

Causes

There are two common causes of bradycardia:

• Diseases of the sinoatrial (SA) node (called sick sinus syndrome). The sinoatrial node is the heart's natural pacemaker.
• Heart block, a specific type of bradycardia in which the electrical signals from the atria (top chambers of the heart) to the ventricle (lower chambers of the heart) may be delayed in some way or completely stopped.

Bradycardia can sometimes be considered normal, such as in athletes and other people who are physically active, or in patients prescribed medications that can slow the heart rate.

Why choose Ohio State for bradycardia treatment?

Ohio State's Ross Heart Hospital has a specialized team of heart rhythm specialists, called electrophysiologists, and more than 100 nursing personnel who specialize in caring for patients with heart rhythm problems. Our electrophysiology program is the largest program in Ohio and one of the top three in the nation, with extensive experience in managing a wide spectrum of heart rhythm problems.

Diagnosis

The first step in the diagnosis of bradycardia is to determine if the slow heartbeat is the cause of symptoms. Your electrophysiologist will begin with interviewing you and completing a physical examination. Based on your symptoms, your electrophysiologist may prescribe a variety of diagnostic tests that may include:

• Electrocardiogram (EKG/ECG) – A test that records the electrical activity of the heart.
• Holter monitor – A portable, battery-operated ECG/EKG that is worn for a day or two and provides your physician with continuous data about the electrical activity of your heart.
• Exercise stress test – A test performed on a treadmill or stationary bicycle to measure heart, lung and muscle function during physical activity. You are attached to an electrocardiogram (EKG/ECG) to record electrical activity of the heart.
• Echo stress test – This test uses sound waves to show moving pictures of your heart at rest and after stress.
• Electrophysiology (EP) study – An invasive test where the doctor inserts a small tube, through a blood vessel, into the heart to measure the health of the electrical system of the heart and to determine if treatment of bradycardia requires a pacemaker.

Treatments

Treatment for bradycardia varies from person to person and depends upon the severity, frequency and cause of the slower heart rate.

Treatment for a slow heartbeat is a pacemaker. Pacemakers are small devices implanted under the skin, most often below your collarbone on the left or right side of your chest. The device sends electrical signals to start or regulate a slow heartbeat.