Stay Well 411 - Heart Rhythm Irregularities – Atrial Fibrillation (A-fib)

By Lenore DiPietro

The heart pumps blood to the rest of the body. The timing of this pump is perfect, beginning at an impulse site known as the SA node.

The heart has its own electrical system, if you will. The two top chambers contract, pushing blood into the two bottom chambers and then out to the body and the lungs.

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When this electrical impulse begins at the SA node, and the heart rate is between 60 and 100 beats per minute, it is called normal sinus rhythm.

However, because of such causes as high blood pressure, coronary artery disease, heart failure and cardiomyopathy, to name a few, the SA node may be prevented from starting the impulse. Many different impulses can fire at once, causing a very fast, irregular rhythm. 

This particular condition is known as atrial fibrillation, or A-fib. The top chambers of the heart are unable to effectively squeeze the blood into the bottom chambers. This can cause the irregular heart rate to be as rapid as 300-600 beats per minute.

Because the top chambers are beating so rapidly and irregularly, blood does not flow through them as quickly. This makes the blood more likely to clot.

If a clot is pumped out of the heart, it can travel to the brain, causing a stroke. People with A-fib are 5-7 times more likely to have a stroke than the general population. Clots can also travel to other parts of the body - like kidneys, heart and intestines, and cause other damage.

The irregularity of the heart makes the heart work less efficiently, and, over a long period of time, can weaken the heart and lead to heart failure.

A-fib can be diagnosed through an EKG, or a Holter monitor, which is similar to an EKG, except it is worn over a 24 hour period and records and stores all of the heart’s electrical impulses. The results are then analyzed and evaluated.

Some symptoms of A-fib include: heart palpitations, lack of energy, dizziness, chest discomfort and shortness of breath.

The goal of treating this condition is to regain normal sinus rhythm, controlling the heart rate, preventing blood clots and reducing the risk of stroke. There are several types of treatments available. Your doctor will advise you as to which treatment will be the most beneficial in your case.

Medications may include rhythm control medications, which are called antiarrhythmic drugs. You may have to stay in the hospital when you first start taking these medications so you can be monitored.

Other types of medications include rate control medications, such as digoxin, or any in a class of drugs known as beta blockers.

Additionally, there are medications that reduce the risk of blood clots. Coumadin and Warfarin are most commonly used.

When medications are unsuccessful, a procedure may be necessary, such as an electrical cardioversion. After you have been given sedation, a synchronized electrical shock is delivered through patches placed on the chest wall. Some invasive procedures include ablation and the placement of a permanent pacemaker.

Atrial fibrillation is not immediately life threatening, but as you can see, you cannot live with this condition for any extended period of time, or it can become so. Even if different medications or procedures have to be tried, a-fib is a highly manageable condition.

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