Vice President Dick Cheney has recently been in the news with a heart rhythm disorder called atrial fibrillation. This condition is more common than you may think.
You may not realize it, but your heart runs on electrical power. That is, the steady, rhythmic beating of your heart inside your chest is controlled by an internal electrical system that spreads and electrical from the top to the bottom of the heart with each heartbeat. But if something in this electrical system goes wrong, the heart’s rhythm can become unsteady and abnormal - causing either an uneven heartbeat or one that’s too fast or too slow.
An abnormal change in heart rhythm is called an arrhythmia, a condition that affects more than 14 million Americans. “Cardiac arrhythmias are extremely common,” says UAB cardiologist Vance Plumb, MD. “Close to 10 percent of older adults have a common type of arrhythmia called atrial fibrillation, which causes a rapid heartbeat and increases the risk of stroke. Also, several hundred thousand Americans die each year of sudden cardiac death due to much more serious arrhythmias that begin in the heart’s lower chambers.”
Some Arrhythmias Aren’t Serious, Others Require Treatment
There are many different types of arrhythmias, most of which don’t cause serious problems. However, some arrhythmias can prevent the heart’s chambers from filling with enough blood or interfere with its ability to pump enough blood to the rest of the body - decreasing blood supply to vital organs. For these types of arrhythmias, treatment is needed to restore normal heart rhythm and blood supply. “Arrhythmias are also more serious for people who have other heart problems,” explains Dr. Plumb.
Symptoms and Early Evaluation
Some arrhythmias are “silent” and don’t cause any noticeable symptoms, while others can cause troublesome symptoms ranging from mild to severe. Your doctor can detect an arrhythmia present during a routine physical exam by listening to your heartbeat with a stethoscope, taking your pulse, or with a special test called an electrocardiogram (ECG). When symptoms of arrhythmia do occur, they might include:
- palpitations or rapid pounding in your chest
- weakness, fatigue, or dizziness
- shortness of breath or fainting
- chest pain
”You should let your doctor know if you experience any these of these possible symptoms of arrhythmia, particularly if you have heart disease or you’ve previously suffered a heart attack,” stresses Dr. Plumb. “Many patients with arrhythmia are referred to a cardiologist, who can perform specialized tests to diagnose the cause of an arrhythmia and recommend appropriate treatment,” he adds.
Precision Diagnosis and Advanced Treatment at UAB Heart and Vascular Center
Some people have frequent and troublesome symptoms of arrhythmia that can’t be controlled with medication. In these cases, a specialized test called an electrophysiology study (EPS) is often performed. This sophisticated procedure allows a skilled cardiologist trained in arrhythmia therapy- also called an electrophysiologist - to pinpoint the exact location of an arrhythmia and restore normal heart rhythm in most cases. “UAB’s electrophysiology group is among the most experienced in the nation,” says Dr. Plumb. “Because we perform approximately 600 procedures each year, we have extensive experience in the diagnosis and successful treatment of all types of complex arrhythmias.”
An electrophysiology study (EPS) is a minimally invasive procedure that involves inserting an electrical catheter - or flexible wire - into a blood vessel located in the patient’s groin or neck. The electrophysiologist guides the catheter into the heart chamber using images created by a fluoroscope - an x-ray-type machine that provides continuous live images of the procedure. Patients are generally sedated but not under general anesthesia during these procedures, though the procedure can be done with only local anesthesia if necessary.
When the catheter reaches the heart muscle, a process called electrical mapping is used to find the source of the arrhythmia. “We record the heart’s electrical activity and map the sequence of electrical flow during the arrhythmia. This allows us to pinpoint the exact location of the problem,” Dr. Plumb explains. Once a target site is confirmed, the electrophysiologist can use a technique called radiofrequency ablation to destroy the area of heart tissue causing the arrhythmia. “We use radiofrequency energy to heat and destroy a small amount of heart tissue and restore normal electrical flow through the heart,” explains Dr. Plumb.
Success rates for this type of treatment are extremely high - a common group of arrhythmias known as supraventricular tachycardias (SVTs) can be cured with this procedure 95 to 99 percent of the time, while a more serious type of arrhythmia called ventricular tachycardia has a cure rate of approximately 90 percent. Dr. Plumb stresses that EPS and radiofrequency ablation have revolutionized the treatment of arrhythmias. “Prior to these techniques, there was no way to cure an arrhythmia. Instead, we tried to manage the condition with medication and monitoring - much like we manage diabetes and high blood pressure,” explains Dr. Plumb. “Now, the treatment is aimed at curing the arrhythmia.”