Pulse Slow

Pulse, Slow

WHEN TO SEE YOUR DOCTOR

* Your pulse falls below 50 beats per minute and stays there, and you are not an athlete.

* You are also experiencing dizziness, weakness, fainting, fatigue or difficulty breathing.

What Your Symptom Is Telling You

If somebody called you "slow" it would be an insult. If they said the same thing about your pulse, it would be a word of praise. When it comes to your pulse rate, slow is generally healthier. Or at the very least, not unhealthy.

Although the normal range for an at-rest pulse is 60 to 100 beats per minute, heart rates below 60—known to doctors as bradycardias—are not all that abnormal or uncommon, according to Joseph P. Ornato, M.D., professor of internal medicine and cardiology at the Medical College of Virginia Hospital of Virginia Commonwealth University in Richmond.

"Often a slow pulse is a sign of completely normal physiology," says Dr. Ornato. "Well-conditioned athletes may have such strong hearts that their pulses are in the forties or even thirties. And in certain individuals, a slower-than-average heart rate, say in the fifties, may be what is normal for their body chemistry."

A slow pulse becomes a concern when it is accompanied by other symptoms. "A pulse becomes too slow when the heart's pumping ability is reduced," says James Willerson, M.D., professor of cardiology and chairman of internal medicine at the University of Texas Medical School at Houston. "When the heart rate is too slow, most people experience disturbing symptoms such as dizziness, fatigue and weakness before they complain about their heart rate."

The bradycardias that are most likely to produce these symptoms, and that most concern heart specialists, are those resulting from disturbances in the electrical impulses that regulate heart rhythm. These conditions, if left untreated, can cause the heart to slip into a state of cardiac arrest.

But a slow heartbeat can also be caused by conditions that are not related to the heart. You could experience a slow pulse following damage to the heart from a heart attack. If the thyroid gland is secreting too little hormone, heart rate can plummet. Hypothermia—a drop in body temperature—can also slow the pulse. Although unlikely in America, severe malnutrition can reduce the heart rate.

Many of the medications used to treat heart conditions—like beta blockers, calcium channel blockers and digitalis—do their jobs by reducing heart rate. So do tranquilizers and sedatives. Other drugs can also produce slow pulses as a side effect.

Symptom Relief

If you otherwise feel fine and have no other symptoms, a pulse on the slow side probably doesn't mean a thing or need any treatment. Only a doctor can tell you if your pulse is indeed "too slow" and prescribe the proper treatment. Here are a few things you should know about.

Have your doctor check your medications. Make sure you're taking the proper medicine and the right dosage. And don't just decide on your own to stop taking your medication. In many cases, such as with certain heart medications, a slow pulse may be the effect your doctor is trying to induce.

Get up to speed with a pacemaker. "If a bradycardia is serious enough to produce other symptoms and interfere with the pumping function of the heart, the most effective treatment is the implantation of an artificial pacemaker," says Lou-Anne Beauregard, M.D., assistant professor of medicine at Cooper Hospital/University Medical Center in Camden, New Jersey. "This device keeps the heart rate going at a level where you can enjoy a normal, productive life."