DEAR DR. DONOHUE: Will you please explain the heart condition SVT? My mom had it, and I had two episodes of it. The second time, I was treated with heart ablation, whatever that is. – J.P.

ANSWER: The two upper heart chambers are the atria. The right atrium receives blood returning from the body, devoid of oxygen. The left atrium receives blood coming from the lungs, and it’s filled with oxygen.

The two lower heart chambers are the ventricles. They pump blood. The right ventricle pumps blood into the lungs, and the left ventricle pumps blood into the body.

SVT is supraventricular tachycardia. Tachycardia is a fast heartbeat. “Supraventricular” indicates that the heartbeat arises in the upper heart chambers, the ones above (supra) the ventricles.

Many different varieties of SVT exist. I can give you an example of one that has a family component. It’s the Wolff-Parkinson-White syndrome. People with this condition have an extra pathway for electrical signals originating in the atria to find their way to the ventricles. When a signal takes this alternate route, the heart speeds up and can cause fainting, among other things.

Frequently, the extra pathway can be destroyed – ablated – by passing a soft, flexible tube into the heart and zapping the pathway with radio waves. The energy from those waves wipes out the alternate path and prevents future episodes of fast heartbeats.

I don’t know the exact SVT you had. The doctor who cared for you can give you that information.

DEAR DR. DONOHUE: About a year and a half ago, my daughter (36) had her tonsils removed. Blood work was done before the operation, and she was told she had strep in her blood. What does this mean, and what should be done about it?

When she was in high school she had mono. Is there any connection? – B.R.

ANSWER: Antibodies to the strep germ were in her blood, not the germ itself. Antibodies indicate prior infection. We all have them. The body fights off infection with antibodies.

Perhaps she had repeated tonsil infections. That would justify the tonsillectomy and would explain why she had strep antibodies. Strep is the germ that most often infects the tonsils.

She doesn’t need to do a thing about the antibodies. There is no connection between mononucleosis and strep infection.

DEAR DR. DONOHUE: How can a thin, very healthy person gain weight but, at the same time, stick to a low-fat, low-cholesterol routine? No one ever asks about weight gain. Everyone asks about weight loss. – D.J.

ANSWER: I’d like to have your height and weight. Many times, being on the thin side is healthy.

I can make gaining weight sound simple, but it isn’t always so simple. The basis of weight gain is taking in more calories than you burn. That’s it.

Get a little book that lists the calorie content of food given in reasonable servings. Every bookstore has many such books. Your homework for a week is to write down daily every morsel of food that passes your lips. At the end of the week, add up each day’s calories, and average out the daily calorie intake for the entire week. This isn’t rocket science.

Add 500 more calories a day to your diet. It’s not hard to pack in an extra 500 calories. For example, a banana has 105 calories. Two bananas a day provide 210 calories. Two-thirds of a cup of raisins has 302 calories. The bananas and raisins give you more than 500 calories. Don’t cut back on the calories you usually eat at mealtime.

You can be creative with the extra calories. You don’t have to eat the same snacks every day. And you can eat foods that have no fat and no cholesterol. Nothing in the plant world (fruits and vegetables) has cholesterol in it, and most have little to no fat. You do, however, need a book with the caloric values of foods.

DEAR DR. DONOHUE: Does baldness come from the mother’s or father’s side of the family? – R.E.

ANSWER: Genes affecting baldness come from the mother’s side, the father’s side or from both sides of the family.

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 www.rbmamall.com

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