Dr. Keith Roach
Dear Dr. Roach: I amscheduled to play tennis with my friend tonight. His son tested positive for COVID-19 and is symptomatic as of yesterday. He has not seen his son for at least one week before the diagnosis. Is my friend safe, and would it therefore be safe for me to play tennis with him? J.G.
Dear J.G.: It is not safe to play tennis with your friend. A person with COVID is potentially infectious for 10 days. Had your friend and his son been exposed at the same time, your friend could be infectious now with an asymptomatic case. It’s also possible that your friend got exposed by his son. Symptoms normally begin within six days after exposure, and your friend would have to have an asymptomatic case to be contagious now. People seem to be most contagious in the early stages. Still, you cannot be sure your friend is not contagious. For that reason, waiting two weeks fromthe time of exposure is best.
Dear Dr. Roach: I am74 with Type 2 diabetes. Recent cardiac studies including a cardiac catheterization revealed a few blockages in my coronary arteries, and I was advised to undergo bypass grafting. I understand arterial grafts are better than venous grafts because they last longer. If this is true, do I have a choice as patient? R.
Dear R.: A cardiac catheterization is a procedure where a small tube (catheter) is inserted into the arteries of the heart and dye is injected with an X-ray machine running to see whether there are blockages in the artery. This is also called a coronary artery angiogram. It’s the definitive test for blockages.
Far fewer bypass grafts are done now compared with 20 years ago. The medications we have for treatment are much better, and fewer people have clear indications that surgery is better than medication treatment. However, people with diabetes do better with surgery in many situations.
A “bypass” means that the blocked area of the artery is bypassed by placing a new blood vessel after the area of blockage, just like a traffic jamcan be bypassed by going on a side road. Using a thick blood vessel does give better results than a thin blood vessel like a vein, often taken from the leg.
Thecardiac surgeon will use an artery whenever it is technically possible to do so. It is far beyondmy expertise to go over all the factors a cardiac surgeon considers. If I were getting the surgery, I might ask whether the surgeon thinks it possible to use the left internal mammary artery, but I would rest comfortably knowingmy surgeon uses his or her expertise to make the best decision for my case.