CT Spots Seeds of Heart Disease in Healthy Patients with Low Cholesterol

Even healthy patients with low cholesterol are at a greater risk of heart attack or stroke if their CT scans show calcium buildup in their coronary arties, a new study has found. 

The study, published in the July 19 edition of the Journal of the American College of Cardiology, involved 3,714 patients in the MESA (Multi-Ethnic Study of Atherosclerosis) trial. Like all MESA participants, they were free of cardiovascular disease, but those selected also had low-density lipoprotein cholesterol (LDL-C) levels of less than 130 mg/dL without lipid-lowering therapies.

The CT scans were used to detect coronary artery calcium (CAC) and carotid intima media thickness to see if abnormalities on these two fronts had impacts beyond traditional cardiovascular risk factors.

After adjusting for myriad risk factors and variables including age, sex, hypertension, diabetes, high-density lipoprotein cholesterol (HDL-C), and triglycerides, the presence of calcium in the coronary arteries predicted a 4.23-fold risk stroke or heart attack at a median follow-up of 5.4 years, lead author Khurram Nasir, MD, MPH, of Yale University and colleagues reported.

"These results may serve as a basis for deciding which patients with low LDL cholesterol may be considered for more aggressive therapies," Nasir and colleagues wrote.

However, they added that cost and radiation-dose concerns make systematic CT screening impractical.