Your heart runs on an intricate electrical system that keeps it pumping rhythmically. But when your heart’s power grid has a "short circuit," your heartbeat may change pace, known as an arrhythmia, or become irregular, known as atrial fibrillation (AFib). A precise diagnosis and treatment is vital — and it could save your life.
The electrophysiology (EP) program at Barnes-Jewish Hospital includes five Washington University cardiac electrophysiologists who offer a complete spectrum of clinical procedures for patients with arrhythmia. They’re also leading the way in developing breakthroughs in treating heart-rhythm disorders.
Curing Atrial Fibrillation With Magnetic Precision
AFib is the most common heart-rhythm disorder, a major cause of stroke and heart failure, and can lead to a severely diminished quality of life. For some people, medication successfully manages AFib. For others, these medications can have problematic side effects or are ineffective.
Mitch Faddis, MD, Washington University cardiac electrophysiologist, and his colleagues are leaders in the use of catheter ablation to treat AFib. The technique moves catheters through the blood vessels to stimulate the arrhythmia with high-frequency electrical impulses and then destroy the abnormal tissue in the heart that is causing it. "The ultimate goal of catheter ablation is to cure atrial fibrillation by restoring the natural rhythm, thus eliminating the need for medications and improving the quality of life," he says.
While Faddis has been successfully using catheter ablation to cure AFib since 2000, he also has been involved with developing a more precise Stereotaxis system to further refine the procedure. "Stereotaxis is a guidance system that uses a magnetic catheter to make it easier, faster and safer to treat atrial fibrillation,"
Faddis says. "The technology allows catheter ablation in difficult-to-reach areas of the heart."
He likens Stereotaxis technology to a remote-control system. During the procedure, a magnetic field created around the patient moves the catheter precisely within the heart to isolate the tissue that causes the arrhythmia. The system is guided remotely with a computer and uses a computed tomography (CT) image to provide an accurate, real-time, three-dimensional map of the heart.
Faddis says the remote-control system excels because it can make tiny movements with extreme precision and also requires less radiation exposure than manual catheter ablation. The procedure is technically demanding for the physician and takes about five hours to complete. But patients can go home the next day and can usually return to work within four days.
"Catheter ablation is an area of medicine where it’s clearly an art that depends on training, experience and ability," Faddis says.
"These are not routine procedures. They’re highly complex, and experience is critical. We have participated in the development of the system since 1998 and were the first in the world to use it in humans in 2002."
Cure rates have improved from 20 percent to 75 percent due to changes in the ablation strategy, according to Faddis.
Targeting Arrhythmias for More Tailored Treatments
Since 2006, Philip Cuculich, MD, Washington University cardiac electrophysiologist, has been working to develop uses for an innovative technology called noninvasive electrocardiographic imaging system (ECGI). ECGI takes the basic electrocardiogram (ECG or EKG) — used for the past 100 years to monitor heart rhythms — to a higher level. The ECGI technology was invented by Washington University biomedical engineer Yoram Rudy, PhD.
ECGI gathers detailed electrical information about the heart from the surface of the body by using 256 electrodes placed on the patient’s chest and back like a vest. A rapid CT scan combined with sophisticated software creates a virtual three-dimensional heart surface, which the ECGI uses to show in great detail how the heart beats.
"ECGI is a noninvasive way to gather information that previously required catheters to be placed inside the heart," Cuculich says.
Because the technology was developed at Washington University, Barnes-Jewish Hospital is currently the only hospital in the world to use ECGI, though only through clinical trials. But, Cuculich adds, many patients who receive care for their arrhythmias or undergo ablation procedures at Barnes-Jewish Hospital also choose to participate in ECGI research projects. He says the ongoing work with ECGI has been very promising for targeting arrhythmias.
"Each patient’s heart-rhythm disorder is unique," Cuculich says. "At Barnes-Jewish Hospital, we take the time to listen and have the advanced technology to understand these subtle but important features that make each person different. By doing so, we can offer safer and ultimately more effective treatment options for heart-rhythm disorders."
Saving More Lives With ICDs
Another area where electrophysiologists at Barnes-Jewish Hospital are making a global impact is through the expanded use of implantable cardioverter defibrillators (ICDs) to prevent sudden cardiac death and heart failure progression.
ICDs, about the size of a stopwatch, are implanted with wire leads connected to the heart. ICDs can also be programmed to serve as pacemakers. The devices can sense the heart rhythm, pace the heart as needed and deliver electrical shocks if heart rhythm becomes irregular or stops altogether.
Until about five years ago, ICDs were only used to prevent sudden death in patients who had a previous cardiac arrest. However, Washington University cardiac electrophysiologists participated in a landmark clinical trial that showed ICDs reduced deaths in a wider population of patients.
Patients may now receive ICDs if they have had a documented heart attack, cardiac arrest, dilated cardiomyopathy (an enlarged heart that can lead to heart failure), or have an ejection fraction of 35 percent or less. The ejection fraction is the percentage of blood ejected from the left ventricle with each heartbeat. A normal ejection fraction is 50 percent or higher.
"Current trials are also blazing the way for using ICDs for cardiac resynchronization therapy earlier in heart failure patients to reduce the disease’s progression," says Marye Gleva, MD, a Washington University cardiac electrophysiologist.
"We’re now reaching people earlier, before their quality of life declines or before they die. Before, we had to wait for something serious to strike before we could use an ICD. Now, we’re able to treat less symptomatic patients. I see patients every day who are alive because of therapy from their ICD.
"We have an amazing legacy here started by pioneering physicians," Gleva adds. "This has become self-perpetuating momentum that leads to innovative thinking across the hospital’s entire cardiovascular and electrophysiology program. Everything we continue to accomplish now is related to this legacy."