Q. My doctor wants me to get a coronary artery bypass, and I'm a little leery. Although I trust my cardiologist, I understand that the operation is quite controversial. My only symptom is a little chest pain after swimming for half an hour. I did flunk a stress test, however, and had an angiogram that showed blockage in three vessels. Wouldn't diet or medication be safer than surgery? A. There is a continuing controversy about the best treatment of coronary artery disease caused by atherosclerosis (hardening of the arteries) -- medical therapy with medications and diet, or surgery. A recent major study, the Coronary Artery Surgery Study, compared surgical and medical therapy and found similar benefits for the majority of patients with stable angina or chest pain.

Factors in favor of medical therapy include: mild symptoms or no symptoms at all; stable symptoms that do not rapidly progress; and good response to a trial of medications that include nitrates, beta blockers and calcium channel blockers.

Certain types of blockages in the coronary arteries, which supply blood to the heart itself, are best treated by surgery.

Surgical treatments include bypass surgery, which entails an operation through the chest wall, and the newer technique of angioplasty, which involves dilating the area of blockage with a catheter that is inserted through the skin into an artery and advanced to the heart. This treatment is generally used on isolated areas of blockage in one or two coronary arteries. However, it sounds like you have more widespread coronary artery disease and are not suitable for angioplasty.

The exact findings on the angiogram and stress test are important considerations, because factors which would favor surgery include: a stress test that suggests severe blockage; the nature of the blockages, because some respond better to surgery than others; younger age, because surgical therapy may improve long-term survival and not just relieve symptoms of chest pain.

Many experts consider three-vessel disease a reason for surgery. Assuming you have significant blockage in three coronary arteries, your condition is probably best treated with bypass surgery. Q. What is Reye's syndrome, and what is its association with aspirin? A. Reye's syndrome is a rare, potentially fatal illness of infants and children, most commonly occurring between ages 6 and 14. Typically, a previously well child develops severe vomiting and mental impairment (confusion, bizarre or violent behavior, or extreme sleepiness leading to coma) just when he seems to be getting over a viral illness.

Reye's syndrome is linked to chicken pox and influenza (flu) infections, and also to use of aspirin. As a safety measure, you shouldn't use aspirin in children with chicken pox or the flu. (Drug companies that make aspirin will be adding this warning to the label on aspirin bottles.) However, if you've given your child aspirin and later discover he has one of these viral infections, you should know the risk of Reye's syndrome remains extremely small.

If you suspect Reye's syndrome in your child, he should get immediate medical attention. Even with intensive therapy, the chances of dying from Reye's syndrome are about one in four. For more information, contact the National Reye's Syndrome Foundation at 1145 19th St. NW, Washington, D.C. 20036 (296-4002). Q. What can be done to help people like myself who cannot swallow pills, even the "easy-to-swallow" kind? I can't take pills or capsules, no matter how small. I'd like to get over this "choking" feeling. A. Difficulty swallowing pills stems more from apprehension than a physical inability to swallow. Sometimes just realizing that you routinely swallow food of different sizes, shapes and consistencies without problem helps in overcoming this difficulty. You also might try swallowing a pill or tablet along with a tiny piece of bread and a mouthful of water.

But if you just can't bring yourself to swallow pills, you can look for substitutes. Most over-the-counter medicines either come in liquid form or have similar brands in liquid form that you can try. For example, you could use liquid acetaminophen (Tylenol and other brands) for pain or fever in place of aspirin, which is not available as a liquid. If your favorite cough, cold or stomach medicine doesn't come in liquid form, ask your doctor or pharmacist to recommend a liquid brand with similar ingredients. Many children's medicines are made as liquids or chewable tablets, so you might look for a "children's" brand instead of "adult" capsules.

Many prescription medicines are also available in liquid form, and you can ask your doctor to prescribe a liquid. If a prescription medicine is available only by tablet or capsule, ask your pharmacist if it's okay to crush or chew the tablet or open the capsule and mix the contents in juice or food such as applesauce. You can't do this with all medicines, particularly most "specially coated," "time release" or "long acting" preparations.

Most medicines are much more expensive in liquid form, so if you can get around your difficulty swallowing pills, it's to your advantage.