Plaque: It146;s not a 145;plumbing problem146;

But the plumbing image is not only mistaken, cardiologists say, it can also lead patients to make disastrous errors in trying to protect themselves from a heart attack.

Plaque is actually a pimple-like growth inside an artery wall. The pimples, stuffed with what Dr Libby describes as a 8220;kind of chronic pus8221;, usually grow outward so they do not obstruct the blood vessel for many years. But once plaque gets started, it covers the walls of the arteries. 8220;It8217;s likely that no part of the artery is normal,8221; he adds.

Arteries removed during autopsies of heart attack patients tell the story. 8220;There are all kind of plaques, cheek by jowl,8221; he says. There is the large, yellow plaque that led to the heart attack. It popped open one day, attracting red blood cells that formed a clot on its surface, blocking the artery. There also are grayish-white plaques, old ulcerated plaques that became calcified. There is so-called vulnerable plaque, the pustules that are ready to burst. And there are yellowish streaks, thought to be plaques starting to develop.

Patients typically have dozens of vulnerable plaques and it is impossible to tell which will burst and result in a blood clot that blocks an artery. 8220;Of 100 ruptures, it is only one that causes a heart attack,8221; says Dr Valentin Fuster, a professor of cardiology at Mount Sinai School of Medicine in New York.

The only thing proven to reduce the risk of a heart attack in someone with vulnerable plaque is the same thing that works to prevent it from developing in the first place, controlling cholesterol levels, blood pressure and blood sugar and not smoking.