Coronary bypass surgery unlikely to cause cognitive decline

Coronary bypass surgery unlikely to cause cognitive decline

The Medicine Cabinet: Ask the Harvard Experts

By Howard LeWine, M.D.

Q: My cardiologist recommended coronary artery bypass surgery because I have three blocked heart arteries and a weak left ventricle. I’m worried about decreased blood flow to the brain during surgery and loss of brain power. What’s the risk of cognitive decline after this type of surgery?

A: Coronary artery bypass surgery (CABG) offers a new lease on life for thousands of people each year whose hearts aren’t getting the blood they need to work properly. But it’s also been blamed for “brain fog,” a loss of memory and thinking skills that follows the procedure in some people. Such brain problems are often called cognitive impairment.

The operation itself may not be to blame, according to research results recently published in the Annals of Internal Medicine. The researchers concluded that intermediate and long-term cognitive impairment after cardiovascular procedures “may be uncommon.” That said, they recommend that anyone thinking about open-heart surgery or another major cardiovascular procedure should discuss the possibility of cognitive impairment with his or her surgeon.

It sounds like you have a heart condition that clearly will be improved by surgery or another invasive procedure. So, the benefit you’ll gain is likely to outweigh the risk of cognitive decline. In addition, the risk of cognitive decline is likely to be greater with drug therapy than with surgery.

Keep in mind that the most important causes of memory loss and a decline in thinking skills are lifestyle choices that harm the brain, not heart surgery.

No matter your age and current health, you can decrease your chance of cognitive decline by:

–Eating a Mediterranean-style diet

–Staying physically active, with dedicated time every day for exercise

–Not smoking

–Maintaining a healthy weight

–Keeping your blood pressure under control

–Keeping your alcohol intake moderate (if you do drink), meaning no more than two drinks a day for men, and no more than one a day for women.

(Howard LeWine, M.D., is an assistant professor of medicine at Harvard Medical School.)

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