Statin Can Reduce Plaques That Cause Heart Attack

Newswise — New research shows that an aggressive statin regimen can reduce the dangerous plaque that clogs arteries, causing heart attacks. Results were presented today at the American College of Cardiology Scientific Session in Chicago and were published today in Circulation, a journal of the American Heart Association.

"Previous studies have shown that statin therapy can slow the development of plaque in the coronary arteries," said Dr. Christie Ballantyne, director of the Center for Cardiovascular Disease Prevention at the Methodist DeBakey Heart & Vascular Center and lead author of the study. "However, no statin monotherapy study has stopped the growth of plaque- or actually reduced the amount of plaque in the arteries in areas with narrowing or stenosis, as this study shows."

Findings from the ASTEROID trial presented today showed that patients with heart disease who took the maximum dose of rosuvastatin (40 mg per day) for 24 months and achieved on average LDL (bad) cholesterol levels below 70 mg/dL and significant increases in HDL (good) cholesterol, had a mean reduction in the plaques that caused blockages in their arteries.

The study used two different imaging techniques to measure different segments of the coronary arteries. Both showed reduction of plaque.

A Study to Evaluate the Effect of Rosuvastatin on Intravascular Ultrasound-Derived Coronary Atheroma Burden (ASTEROID) was designed to determine the effects of treatment with rosuvastatin on progression of coronary atherosclerosis in patients who had a clinically indicated cardiac catheterization that showed angiographic evidence of coronary artery disease (CAD). This study examined whether rosuvastatin could regress coronary atherosclerosis as assessed by intravascular ultrasound (IVUS, the primary endpoint) and quantitative coronary angiography (QCA, a secondary endpoint). As previously reported, IVUS assessment of a single coronary artery with <50 percent angiographic luminal narrowing showed atheroma volume regression. Today's findings showed that the treatment also produced regression by decreasing percent diameter stenosis and improving minimum lumen diameter (MLD) as measured by QCA.

About the studyASTEROID was a prospective, multi-center, international open-label trial that enrolled men and women 18 years or older with a clinical indication for coronary catheterization and angiographic evidence of CAD who met specific angiographic and IVUS criteria. Inclusion required demonstration of at least one obstruction causing more than 20 percent angiographic luminal diameter narrowing in any coronary vessel. The left main coronary artery had to have ≤50 percent reduction in lumen diameter by visual estimation, and the target vessel for IVUS interrogation could not have undergone angioplasty or bypass surgery nor have >50 percent luminal narrowing throughout a target segment with a minimum length of 40 mm. Segments for QCA analysis could not have undergone angioplasty or bypass surgery.

ASTEROID treated 507 coronary disease patients with rosuvastatin 40 mg/day for 24 months. Of these patients, 379 had evaluable angiograms at baseline and at study end. Blinded QCA analysis of percent diameter stenosis (%DS) and minimum lumen diameter (MLD) was performed for up to 10 segments of the coronary arteries and their major branches with >25 percent diameter stenosis at baseline. For each patient, the means of all matched lesions at baseline and study end were calculated. There were 292 patients with 613 matched segments that met the criterion of >25 percent stenosis.

ResultsRosuvastatin reduced low-density lipoprotein cholesterol (LDL-C) by 53.3 percent to 61.1±20.3 mg/dL; high-density lipoprotein cholesterol (HDL-C) increased by 13.8 percent to 48.3±12.4 mg/dL. Mean±SD percent diameter stenosis decreased from 37.3±8.4 percent (median [minimum"maximum] 35.7 percent [26"73 percent]) to 36.0±10.1 percent (median 34.5 percent [8"74 percent]; p<0.001). MLD (minimum lumen diameter) increased from 1.65±0.36 mm (median 1.62 [0.56"2.65] mm) to 1.68±0.38 mm (median 1.67 [0.76"2.77] mm; p<0.001). The trial was funded by AstraZeneca.

Dr. Ballantyne will present this study, "Effect of Rosuvastatin Therapy on Coronary Artery Stenoses in the ASTEROID Trial" at the ACC's 57th Annual Scientific Sessions on Monday, March 31, at 10:45 a.m. in North Hall B1.

For more information on the Methodist DeBakey Heart & Vascular Center, see http://www.debakeyheartcenter.com.