DEAR DR. DONOHUE: I am 43 and in good health – at least, I thought I was. I went for my first physical exam, and the doctor spent a great deal of time listening to my heart with his stethoscope. He told me I have a heart murmur and that I probably have mitral valve prolapse. I am scheduled to have an echocardiogram. Does this mean I have serious heart trouble? – R.P.

ANSWER: Probably not. Mitral valve prolapse is a fairly common condition, with 3 percent or more of the population having it.

The mitral valve lies between the upper and lower left heart chambers, the left atrium and left ventricle. It’s closed when oxygen-carrying blood coming from the lungs empties into the left atrium. When the atrium fills, it opens, and blood flows into the left ventricle, the pumping chamber that propels blood to the entire body.

A prolapsing mitral valve is one that balloons upward when the valve closes. Most people with mitral valve prolapse don’t know they have it. Usually the doctor picks it up when he or she listens to the heart. The doctor hears a peculiar sound and a murmur.

Echocardiograms – soundwave pictures of the heart – show the ballooning valve and also show any valve leakage. If the valve is not leaking, generally nothing need be done.

If there is a valve leak, then those patients have to take antibiotics before any surgical or dental procedure that seeds the blood with bacteria. Leaking valves are targets for bacterial infections. With large leaks, doctors suggest surgical correction.

Mitral valve prolapse might also be responsible for abnormal heart rhythms that can often be suppressed with medicines.

For most, mitral valve prolapse is simply an oddity that causes no great trouble. It’s often a family affair. One of your parents probably had it.

The booklet on heart valve disorders discusses the many kinds of heart valve problems and what’s done for them. Readers can obtain a copy by writing: Dr. Donohue – No. 105, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6.75 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: How often should someone with a vitamin B-12 deficiency get a B-12 injection? – J.B.

ANSWER: For the treatment of pernicious anemia – the consequence of B-12 deficiency – people take B-12 shots weekly for the first eight weeks of treatment and then monthly for life.

Some doctors have their patients take large doses of B-12 by mouth instead of shots. The large dose is given because most people who have too little B-12 are poor absorbers of the vitamin. A B-12 deficiency can be satisfactorily overcome with the oral route.

DEAR DR. DONOHUE: After reading your article on the side effects of quinine, I wonder if I need to worry about drinking tonic water with my scotch. Tonic water has quinine in it. Should I change to soda? I have only one drink a day. – C.T.

ANSWER: You can drink tonic water without worry. The amount of quinine in it is not enough to cause any trouble.

DEAR DR. DONOHUE: I am 83. I fell and hit my head. My son took me to the emergency room, and the doctor thought I might have had a blood clot in my brain, so he ordered a CT scan. I didn’t have a clot, but I do have a tumor called a meningioma. I saw my own doctor for a follow-up, and she said I don’t need to do anything about it. Is it safe to ignore a brain tumor? – R.S.

ANSWER: Meningiomas are benign tumors of the brain coverings. They don’t spread. They grow very slowly. Unless they’re large and put pressure on the brain and cause symptoms, you don’t have to do anything about them. If yours hasn’t bothered you yet, it’s unlikely to bother you at any time in the future.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from

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