What is arrhythmia?



Arrhythmia (uh-rith-mee-uh)— also called abnormal heart rhythm or heart rhythm disorder — is an irregular heartbeat, heart rate or rhythm. Your heart is a powerful muscle that pumps a continuous supply of blood, oxygen and other nutrients through the body. To accomplish this task, your heart needs to regulate the timing of its beats, or rhythm. Your heart’s electrical system controls the rhythm.

At some time in life, most adults experience a racing heart, an extra heartbeat or a skipped beat. Many of these rhythm changes are passing and harmless. Certain arrhythmias, however, especially those that last long enough to affect the function of the heart, are serious and can be fatal. A serious arrhythmia may be a sign of coronary artery disease, heart muscle disease, heart valve disease or other heart problems.

Common Abnormal Heart Rhythms

Atrial Fibrillation
The most common type of arrhythmia is atrial fibrillation (AF). AF causes the upper chambers of the heart (atria) to quiver rapidly and irregularly. As a result, the atria don’t “prime” the lower chambers of the heart (ventricles), which causes them to also beat rapidly and irregularly. The lack of priming and the rapid and irregular beating makes the heart pump less effectively. 

AF affects more than two million people every year. The chances of developing AF increase with age. Research in recent years has shown that AF can be quite serious and lead to complications such as stroke and heart failure.

Sudden Cardiac Arrest
Sudden Cardiac Arrest (SCA), or Sudden Cardiac Death, is an arrhythmia of the heart and occurs when the electrical signal that controls the pumping of the heart misfires. The result is ventricular fibrillation, where the lower chambers of the heart begin to quiver and cannot pump blood to the brain.

Unfortunately, SCA is a leading cause of death in the United States that kills 325,000 Americans every year. It is responsible for half of all heart disease deaths and more deaths than AIDS, breast cancer and lung cancer combined.

Electrophysiologists: Heart Rhythm Specialists
An electrophysiologist is a cardiologist with additional education and training in the diagnosis and treatment of abnormal heart rhythms. Close collaboration is important between electrophysiologists and other doctors who treat patients with heart disease. The Heart Rhythm Services medical staff at Oregon Heart & Vascular Institute includes two electrophysiologists.

James McClelland, MD Electrophysiologist Oregon Cardiology  Medical Director,  Heart Rhythm Services  Oregon Heart & Vascular Institute

Ramakota Reddy, MD Electrophysiologist Oregon Cardiology

How are Arrhythmias Diagnosed?
The heart’s electrical system is complex, so diagnosing problems such as arrhythmia may require special equipment along with skilled medical professionals.

Your doctor may request certain tests, including:

• Echocardiogram — an ultrasound exam that uses sound waves to evaluate the size, pumping strength and valves of the heart.
• Electrocardiogram (EKG) — a recording on graph paper of the electrical impulses generated by the heart.
• Exercise stress test — a test used to assess the effect of stress on the heart brought on by exercise.
• Holter monitoring — an exam that helps determine how the heart responds to normal activities and heart medications.
• Event monitoring — measurements of a small, portable recording device that captures fleeting episodes of abnormal heart rhythm for up to a month.
• Nuclear medicine test — a test that uses low-dose radiation to create images that show blood flow to the heart.
• Electrophysiology study — a test to determine the characteristics, or specific features, of abnormal heart rhythm.

Treatments
Treatment is highly individualized and based on severity and symptoms. Current treatment options include:

• Medications to keep heart rates in the normal range; blood thinner medications such as Coumadin, which are effective in preventing stroke; or a combination of heart rate control medications and blood thinners.
• Cardioversion, a procedure in which an electrical charge is delivered to the heart so that it beats regularly again, performed in the early stages of AF and usually followed up with a medication regimen.
• The use of implanted electronic devices such as a pacemaker or an implanted cardioverter defibrillator.
• Minimally invasive surgical procedures intended to permanently cure atrial fibrillation, include:

• Catheter Ablation, a procedure used to cure abnormal heart rhythms, which uses catheters—narrow, flexible wires—to detect and destroy electrical problem areas in the heart and restore normal electrical activity.
• Mini-Maze, a relatively new, minimally invasive, surgical technique used to cure AF in which surgeons use a very precise instrument to destroy a small amount of tissue in the area near where the irregular signal starts. The damaged tissue can no longer conduct electrical impulses, interrupting the transmission of the abnormal signal and allowing the rest of the chamber to resume beating normally.

To learn more about the latest procedures around heart arrhythmias, visit www.minimaze.org, a Web site dedicated to the subject of atrial fibrillation and the Mini-Maze and catheter ablation curative techniques.

Your care is a partnership between your doctor and our cardiology and electrophysiology specialists. Together, they work to assure your heart’s return to a steady beat.

Print a copy of our:
Heart Rhythm Services brochure
Atrial Fibrillation flyer
Sudden Cardiac Arrest flyer
Mini-Maze flyer
Catheter Ablation flyer