You might wake up feeling perfectly fine, with no signs of illness, yet your arteries could already be partially blocked and your heart quietly under pressure. Blocked arteries often don’t show symptoms until something severe happens—like a heart attack or stroke.

Cardiovascular diseases are responsible for nearly 18 million deaths globally every year, mostly affecting individuals unaware they’re in danger.

Being aware of the following nine symptoms—some of which may seem minor or unrelated—can help you spot trouble early and possibly save your life.

1. Chest discomfort or pain