Q: I was just diagnosed with atrial fibrillation. Can you tell
me about the different treatments for this condition?
Q: I was just diagnosed with atrial fibrillation. Can you tell me about the different treatments for this condition?
A: Atrial fibrillation is one of the most common heart rhythm disorders. One in every four Americans age 40 and older will develop the condition at some time in his or her life.
The problem stems from a glitch in the heart’s electrical system. The surges of electrical activity that coordinate heartbeats go haywire. Often, people don’t even have any symptoms.
But if they do, one common symptom is the fluttering sensation of a racing heart – what some people call palpitations. With or without that sensation, a person may have shortness of breath or suddenly feel tired. Some people feel lightheaded and may even faint during an episode.
Atrial fibrillation cuts the heart’s pumping ability by about 20 percent. An otherwise healthy heart can compensate for this problem.
But people whose lower heart chambers (ventricles) are weak or who have faulty heart valves can develop problems. For these people, atrial fibrillation can produce or worsen the symptoms of heart failure, which includes fatigue, shortness of breath and swelling in the feet and ankles.
If a person has just one or two isolated episodes of atrial fibrillation, it usually doesn’t need to be treated.
But people who have persistent cases or who go in and out of atrial fibrillation definitely need treatment. Two different kinds of treatments are needed: treatment to slow or regularize the irregular rhythm and blood-thinning treatment.
The irregular rhythm of atrial fibrillation can be treated in two ways. One is known as rate control, which uses drugs called beta blockers (atenolol, metoprolol) or calcium channel blockers (verapamil, diltazem) that help slow down the heart rate.
The other main type of treatment is rhythm control, which tries to correct the heart’s faulty rhythm so it beats normally again. Most doctors currently use a so-called anti-arrhythmia drug called amiodarone (Cordarone, Pacerone).
Sometimes, people who take this drug are hospitalized when they begin taking this or a similar drug, so doctors can monitor them for side effects.
In general, doctors tend to recommend the rate control approach. Rate-control drugs are easier to use, less expensive, and have fewer side effects.
However, some people still have symptoms while taking these drugs. When this happens, switching to rhythm-controlling drugs makes sense. The good news is that several studies comparing different treatments for atrial fibrillation found that both strategies work equally well in preventing strokes.
Sometimes the underlying abnormality in the heart’s electrical system that causes atrial fibrillation can be permanently fixed using high-frequency radio waves.
A special instrument is passed through a vein in the groin and up to the heart. The idea is to create scar tissue that blocks the unwanted electrical signals that trigger atrial fibrillation.
This relatively new technique is reserved for people who have not been helped by other treatments.
The second kind of treatment needed with atrial fibrillation is blood thinners. In atrial fibrillation, the heart’s upper chambers (atria) quiver and twitch.
When this happens, small, stagnant pools form in the atria, and blood clots tend to form. If a clot forms and breaks off, it can travel through the bloodstream and lodge in an artery. If the artery is in the brain, the result is a stroke.
Older people and those with other risks for stroke — such as smoking or having uncontrolled high blood pressure – face the highest risk.
The most commonly used treatment to prevent blood clots from forming is the blood-thinning drug called warfarin (Coumadin).
In some studies, people with atrial fibrillation who took warfarin cut their risk of stroke by 70 percent. But finding the right dose of warfarin can be tricky. It has to be high enough to prevent blood clots, but low enough to avoid the risk of bleeding.
People taking warfarin must have frequent blood tests to see if their blood is in that safe range and adjust their dose, if needed.
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