By Susan J. White
NorthShore University HealthSystem

Arrhythmia—an abnormal heart rhythm—is an extremely common condition, especially among older people. According to the American Heart Association, millions of Americans will have arrhythmias each year.

Many of them are harmless; however, some who suffer from repeated arrhythmias often have a variety of uncomfortable symptoms and pain including a very fast heart rate to the point of feeling like their heart will jump out of their chest or feeling faint, and some are exposed to serious risks, including dying suddenly. Thanks to advances in the relatively young field of cardiac electrophysiology, the vast majority of arrhythmias are treatable.

What started as a research tool to better understand the electrical properties of heart tissues has evolved in less than 50 years to an important medical specialty, says NorthShore University HealthSystem (NorthShore) Associate Director of Cardiac Electrophysiology Jose Nazari, MD.

Early interventions with defibrillators in the mid-eighties represented the first real treatment options for arrhythmias, according to Dr. Nazari, but the real breakthrough came when physicians began using electricity inside the heart to burn off the short circuits that caused the arrhythmia. Prior to this discovery, heart surgery was the only option for treatment; however this is highly invasive and requires electrophysiologists to determine the site of treatment, since surgeons must stop the heart and all electrical activity during open heart surgery.

Refining the latest discoveries of cardiac electrophysiology with technology initially used by neurosurgeons led to what is now the gold standard treatment for most arrhythmias—radio frequency ablation, Dr. Nazari says.

In an ablation procedure, a thin catheter is inserted through a vein or artery to a highly targeted section of the heart muscle and a burst of energy is used to destroy a precise area of tissue causing the abnormal electrical signal or arrhythmia. The success rate in these procedures is now close to 100 percent in terms of curing most common arrhythmias, adds Dr. Nazari.

The whole area of cardiac electrophysiology is continuing to evolve with numerous active research efforts and clinical trials addressing treatment for atrial fibrillation, a condition where the two smaller chambers of the heart (atria) beat irregularly and too fast. Atrial fibrillation is one of the major causes of stroke and can have other very serious consequences, explains Dr. Nazari.

There are some disorders like high blood pressure and lifestyle considerations like smoking, diet and exercise that can induce atrial fibrillation. It can also occur as an inherited condition or in the absence of other obvious heart abnormalities. This is a disease that is now treatable with an ablation procedure.

NorthShore and others are involved in a large clinical trial comparing treatment of atrial fibrillation with ablation versus pharmacological interventions, Dr. Nazari says.

Other areas of research and ongoing advancements in electrophysiology include new developments in pacemakers and defibrillators, particularly beneficial for congestive heart failure patients, who often get off the table and immediately feel better following a resynchronization pacemaker implantation, he explains.

As pacemaker technology improves, they now work to resynchronize the right and left sides of the heart as opposed to initial devices that worked on just one side.

Implanting defibrillators is another important advancement in the field. As physicians have become better able to identify patients at risk for sudden cardiac arrest and death, they can now address the condition prophylactically with a defibrillator, dramatically improving outcomes and survival rates.

For more information about NorthShore University HealthSystem’s Cardiovascular Care Center, please go to www.northshore.org/heart.