Cardiac Ablation Maps and Corrects Faulty Heart Wiring
Ten years ago, David Moore, of San Mateo was playing volleyball on a hot day when he suddenly grew lightheaded. The investment manager initially shrugged off the incident. “Must be heat exhaustion,” he told himself. But the sensation returned sporadically for the next six years until, one day in the middle of a volleyball game, something suddenly felt very wrong in his chest.
“When I went back to the office after the game, I felt like I would pass out when I reached the top of the stairs. Thinking I was having a stroke, my wife took me to the emergency room, but after a CT scan and electrocardiogram, the doctors told me they could see AFib,” he recalls.
One Condition, Many Worries
AFib, or atrial fibrillation, is a quivering or irregular heartbeat caused when the upper chambers of the heart (the atria) get stuck in a rapid irregular rhythm. As a result, the chambers that pump blood to the lungs and organs cannot fill normally. For David, it felt like he had a pinball machine in his chest, combined with dizziness, shortness of breath and a tight chest.
Approximately 3 million to 5 million Americans have AFib, making it one of the most prevalent types of arrhythmia (see page 10 for more information). The condition alone is not life-threatening but can be progressive. Intermittent at first, the episodes can grow more frequent and last longer until the heart becomes stuck in a dangerously irregular rhythm.
AFib also comes with troublesome complications. First, it gives you unpleasant symptoms, as David experienced: “It becomes a nasty psychological thing because you’re always worried about it. Once I went into AFib one hour before I had to present to 100 people. I was afraid I’d be so out of breath, I couldn’t speak. You start cutting back on activity because you’re worried you might have an event.”
“The second issue with atrial fibrillation is that it can increase your risk of stroke up to five times,” says Steven Hao, M.D., a cardiac electrophysiologist and director of Sutter Health CPMC’s Atrial Fibrillation and Complex Arrhythmia Program. “When the atrium is beating quickly, it doesn’t squeeze the blood effectively. Blood can pool, clots can form, and if one breaks off, can lead to stroke.”
Third, when the top chamber of the heart beats extremely fast in AFib—approximately 300-400 beats per minute— the bottom chamber of the heart can also respond quickly, faster than the normal 60-100 beats per minute. This puts stress on the heart, almost like a car engine stuck in an accelerated position. Heart failure can result.
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Seeking a Permanent Solution
Some people with AFib who don’t have symptoms or are too elderly or sick for more aggressive therapy can simply live with AFib, taking blood thinners to prevent stroke and keeping their heart rate slow to minimize the stress on the heart.
For David, his cardiologist prescribed anti-arrhythmic drugs, which try to prevent AFib from starting, and can work in 35-60 percent of patients. While this regimen seemed to help short term, he worried about taking these drugs long term, given potential side effects and toxicity to other organs.
Eventually, David met with Dr. Hao, who suggested he consider ablation. This procedure involves inserting a catheter into the heart through veins in the leg and/or neck, mapping the sources of the excess electrical “noise” that cause the AFib, and disconnecting those areas so they will no longer disrupt normal heart rhythm. At CPMC, doctors use state-of-the-art tools, including intracardiac echocardiography and a 3D mapping system (similar to a GPS system), to map and maneuver safely and accurately inside the heart. CPMC’s ablation program is one of the busiest in the nation, performing of these procedures each year. It also serves as a technical expertise center, where doctors from around the world learn to perform cardiac ablation for AFib.
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Experience Breeds Success
AFib ablations have a high success rate: 78 percent after one procedure and 90 percent after two procedures. David underwent two procedures over the course of 11 months, each lasting two hours. Following overnight monitoring at CPMC, he returned home and went back to work in five days.
Today, David takes only a daily aspirin as a general heart health precaution. He walks and plays volleyball regularly. And his heart feels as normal and healthy as ever. He says he’d recommend ablation to anyone with AFib but cautions that finding an experienced specialist is paramount.
“With any procedure, the key is to find someone who does a high volume and is really good at it,” he says. “In my case, I knew my AFib was getting worse and the medications had little success, so ablation was the best solution. Now I don’t have the worry about my AFib anymore. I can do anything I want."
Visit cpmc.org/ablation to see a video on cardiac ablation and learn more about irregular heartbeat.
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When a Normal Heartbeat Goes Awry
Perhaps nothing seems more normal in our bodies than our heartbeat—that is, until something goes wrong. Glitches in the heart’s electrical system can lead to arrhythmias, abnormal heart rhythms.
Here are a few common forms and their symptoms:
BRADYARRHYTHMIAS— The heart beats too slowly.
Cause: Problems with the heart’s sinus node (built-in pacemaker) or the way the signals are conducted due to wear and tear to the heart (age), side effects from medication, or damage from another disorder.
Symptoms: Fatigue, dizziness, fainting, shortness of breath.
TACHYARRHYTHMIAS— The heart beats too quickly.
Cause: Heart cells (foci) misbehave or an abnormal circuit in the heart develops that causes electrical signals to conduct too rapidly.
Symptoms: Fluttering, dizziness, fainting, shortness of breath and fatigue.
Irregular Heart Beating— Single extra beats between regular heartbeats.
Cause: Various causes, including atrial fibrillation.
Symptoms: Sensation of skipped heartbeats or pauses.
All abnormal heart rhythms should be evaluated by a physician immediately to put your mind at ease or direct appropriate care. Treatments can range from observation to pacemakers to cardiac ablation – the internal mapping and correction of misfiring circuits.
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