"Ridding the heart arteries of plaque was previously thought to be unattainable," says researcher Steven Nissen, MD. Nissen is interim chairman of the department of cardiovascular medicine at The Cleveland Clinic.
"But what we found is that if you lower LDL cholesterol to very low levels and keep it there for two years, you can remove plaque in fairly significant quantities and partially reverse coronary artery disease," he tells WebMD.
"This is very exciting research that breaks new ground," says David O. Williams, MD, a cardiologist at Brown University in Providence, R.I., who moderated a news conference to discuss the study.
The findings, which were released at the annual meeting of the American College of Cardiology, were simultaneously published online in The Journal of the American Medical Association.
In the current study "we wanted to push the paradigm as far as it would go," he says.
The study included about 350 people who took high doses of another statin, called Crestor, for two years. All the participants had at least one fatty blockage clogging a major heart artery.
Raising HDL 'Good' Cholesterol
Nissen says the previous studies suggest that Crestor may be more potent than other statins, "with a greater capacity to lower LDL and perhaps to raise HDL." LDL is "bad" cholesterol and HDL is "good" cholesterol.
By snaking a small ultrasound probe into the coronary arteries, the researchers showed that Crestor reduced the volume of plaque in the arteries by 6.8%.
Average LDL cholesterol levels dropped from 130.4 mg/dL at the start of the study to 60.8 mg/dL, "which is the lowest level ever achieved in a statin trial," Nissen says.
To the researchers' surprise, there was also an unprecedented rise in "good" HDL cholesterol levels, from 43.1 mg/dL at the start of the study to 49.0 mg/dL two years later, he says.
The findings suggest that "rather than use target levels of LDL, let's get our patients as low as we can without safety issues," Nissen says.
LDL levels of less than 100 mg/dL are considered optimal, while HDL levels of 60 mg/dL or higher are considered protective against heart disease, according to the American Heart Association.
Williams notes that not every person with fat-clogged arteries will benefit. In the study, plaque regressed in about 64% to 78% of participants, Nissen says.
"But what that means," he adds, "is that if you achieve these low lipid levels, there's a pretty good chance you will regress."
There were "no obvious safety issues," although some patients did experience elevations in liver enzymes similar to those seen in other statin studies, he says.
Other Statins May Work
Roger S. Blumenthal, MD, of the Johns Hopkins Ciccarone Preventive Cardiology Center in Baltimore, says he believes that unprecedented rise in HDL (the good cholesterol) is one of the most exciting findings of the trial.
While no one knows for sure, "the HDL improvement probably played a large role in the plaque regression," he says.
So will other statin drugs also reverse plaque buildup?
No one knows that yet either, Nissen says. "But if you achieve these low LDL levels by other means, you would probably get the same results. It just hasn't been tested."