Ask the doctors: Can surgery cause a heart attack?

Q. A friend with heart disease was doing fine until he underwent an operation for colon cancer. He got through the first few days without any problems, but then had a heart attack on the fourth day and nearly died. Why would he have had a heart attack after an operation? I need to have surgery and am wondering how dangerous it will be.

A. A major operation isn't like an exercise test, where the stress ends as soon as you stop walking on the treadmill. After an operation, the body has to repair the damage that was done. Inflammation created during the repair process increases the tendency of blood to clot, not only at the site of the surgical wound, but also in the arteries of the heart. Thus, the risk of heart problems after surgery continues for several days after the operation is over.