What is atrial fibrillation?
Atrial fibrillation is an irregular and often rapid heart rate that commonly causes poor blood flow to the body. Commonly known as a fluttering or racing heart, atrial fibrillation is the most prevalent of abnormal heart rhythms, affecting 2.7 mi...
Atrial fibrillation is an irregular and often rapid heart rate that commonly causes poor blood flow to the body.
Commonly known as a fluttering or racing heart, atrial fibrillation is the most prevalent of abnormal heart rhythms, affecting 2.7 million Americans.
The disease affects the rate and rhythm of the heartbeat, making the heart beat too fast, too slow or with an irregular rhythm. It can lead to heart failure or contribute to stroke.
During atrial fibrillation, or A-Fib, the heart's upper two chambers (the atria) beat chaotically and irregularly -- out of coordination with the two lower chambers (the ventricles) of the heart.
"With A-Fib, there's a storm of electrical signals going on," said Dr. Hung-Kei Li, cardiac electro-physiologist with Sanford Health in Fargo. The upper chambers of the heart are being bombarded with fast, irregular electrical signals.
"The heart is being stimulated at 400 beats per minute. Nothing can beat that fast. The lower chambers (of the heart) are affected as well."
The adult normal resting heart rate is 60 to 100 beats per minute.
Symptoms include heart palpitations, irregular heartbeat, fatigue, shortness of breath, light-headedness and weakness. They may come and go; in more severe cases, symptoms may be long-lasting or chronic.
Although A-Fib itself isn't usually life-threatening, it is a serious medical condition that sometimes requires emergency treatment. It can lead to complications.
The earlier it is treated, the better the outcome for the patient.
When blood is not being pumped properly, it can pool in the upper chambers of the heart. This pooling can cause a blood clot to form. If the clot breaks away and travels to the brain, it can block an artery and cause a stroke.
Treatment for A-Fib may include medications and other interventions aimed at altering the heart's electrical system.
Li uses a new technique, called "cryoballoon ablation," to target the veins in the heart most responsible for triggering A-Fib. He is among a small number of cardiologists around the country who perform this procedure.
Ablation involves destroying cells, through the use of intense heat or cold, and creating scar tissue around those veins to contain the chaotic electrical signals that cause A-Fib. Electrical impulses cannot pass through scar tissue.
Cryoballoon ablation, a method of freezing the cells to create scar tissue, was developed to ensure a complete ring of scar, with no gaps to allow the flow of electric impulses.
The heart is accessed by threading a catheter in through the groin or neck, making the procedure far less invasive than surgically opening the chest.
The success rate with this technique is higher than treatment with medications, he said.
"Atrial fibrillation is not just a disease of the heart itself, it's more complicated," Li said. "It involves the heart and brain and peripheral nervous system."
Causes include uncontrolled high blood pressure, untreated sleep apnea, valve disease, a leaking valve, heart failure, lung disease and smoking or exposure to smoke, he said.
Age is also a factor, he said. "If we all live long enough, all of us will have some A-Fib at some point in our lives."
Sleep apnea "is a major aggravator to the brain or heart," he said. He recommends that this condition be treated before treatment for A-Fib begins.
Diabetes, alcohol use and weight can also play a role in A-Fib, he said.
"Weight is a big issue here," he said. "Studies (in the U.S. and Europe) with thousands of patients show that the more weight you lose, the less likely that A-Fib will come back."
The ailment "is not necessarily genetic, but it can be," he said. He has seen "clusters" of the disease in families.
Stress too may play a role, "but no one can prove it," he said.
In recent years, surgery to correct A-Fib "has fallen out of favor because it is so invasive and (requires) long recovery," he said. "Surgery harmed (the body's) own God-given pacemaker and patients wind up needing a pacemaker."
Li urges patients "to try to control A-Fib at its earliest possible point," he said. "Put a lid on the problem when it is small."
Types of atrial fibrillation:
• Paroxysmal: Symptoms come and go on their own.
• Persistent: More advanced; more spots in the heart chambers are affected.
• Long-standing or chronic: More serious type; symptoms last more than a year.