Q: A close friend of mine who seemed perfectly healthy just had a positive exercise stress test. That makes me wonder if I should have one, too. When is it a good idea to have an exercise stress test?
A: During an exercise stress test you have a continuous electrocardiogram (EKG) done while walking on a treadmill. The exercise is made progressively more strenuous by gradually increasing the speed and incline of the treadmill. An abnormality in the stress EKG can detect a significant narrowing in your coronary arteries that might not be evident on an EKG taken while at rest.
But stress tests are far from perfect. Problems include both false negatives -- a normal stress EKG despite the presence of significant coronary artery disease -- and false positives, which means an abnormal stress EKG in the absence of significant coronary artery disease.
You definitely should have a stress test if you have angina or any other symptoms that suggest coronary artery disease or other heart disease. Or if you are a sedentary person over the age of 50 about to start a vigorous exercise program. A stress test could be quite useful if you are over 55 and have one or more of the major heart disease risk factors: high cholesterol, high blood pressure, cigarette smoking, diabetes, a history of heart attack before age 55 in a parent or sibling, or being more than 30 percent overweight.
A stress test is not a good idea if you are a healthy young individual because there is a greatly increased chance of a false positive test.
Q: I would like to find out the symptoms of carpal tunnel syndrome and the results of surgical treatment. Does carpal tunnel affect your arm and neck? Does it develop into arthritis? What are the effects of surgery?
A: Numbness and tingling in the hand are often the first manifestations of carpal tunnel syndrome. Symptoms may progress to burning, aching, loss of strength, and a swelling sensation in the fingers. Aching may extend into the forearm and higher in the arm, but not to the neck. Surgical release of pressure on the median nerve, which causes the syndrome, is quite effective in abolishing the symptoms. There are no residual ill effects of surgery unless the nerve is damaged during the operation or poor surgical techniques lead to excessive scar tissue.
Carpal tunnel syndrome does not develop into arthritis but some types of arthritis, such as rheumatoid arthritis, may cause the syndrome.Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine and associate dean for academic affairs.at the school.