You may be carrying one of the most significant cardiovascular risk factors in medicine — and have no idea. Lp(a) is a genetically inherited particle in your blood that raises the risk of heart attack, stroke, and aortic valve disease. Elevated Lp(a) is present in roughly one in five people. And most people have never been tested for it, even though U.S. guidelines now recommend testing every adult at least once.

Your last cholesterol panel came back normal. Here’s why that might not mean what you think it does. Cardiovascular disease remains the leading cause of death in both men and women. And a significant percentage of heart attacks happen in people whose LDL cholesterol was, by conventional standards, normal. The more accurate signal is something called ApoB. Most physicians don’t order it. Most patients have never heard of it. That needs to change.