Rethink on the impact of plaque build-up

The notion that soft atherosclerotic plaque is more dangerous than hard calcium deposits for heart risk may be wrong, say cardiologists.

Their research suggests it's more the calcified plaque in coronary arteries that’s behind adverse cardiovascular events.

The findings may be a "game-changer" for determining who's at risk of myocardial infarction, they say.

The team from three major US medical research institutions analysed the composition of plaque from 224 patients who had diabetes, but no heart symptoms.

After nearly seven years of follow-up, they unexpectedly found proportionally high quantities of calcified plaque best predicted major adverse cardiac events, while soft plaque did not.

While further studies are needed to verify the findings, the researchers say this focus on coronary calcium may represent a potential paradigm shift.

"It's a disease marker, not a risk marker”, says co-author and cardiology researcher Dr Brent Muhlestein, who noted that having a calcium score of zero is like having a five-year warranty against MI — even with high levels of low-density lipoprotein.

“The finding potentially could mean a lot of patients may not require statin therapy, even though they have high cholesterol," he says.

"Maybe we can find and identify them. If there's no atherosclerosis, you're not going to have a heart attack. So the coronary calcium score may allow us to much more effectively select who we treat."

The paper was presented at the American College of Cardiology Scientific Sessions in Washington DC on Friday.