Lipoprotein(a), Cholesterol, Triglyceride Levels, and Vulnerable Coronary Plaques: A PROSPECT II Substudy.

Area of Science:

• Cardiovascular Medicine
• Atherosclerosis Research
• Lipid Metabolism

Background:

• Lipoprotein(a) (Lp[a]) is a known risk factor for acute myocardial infarction (MI).
• The specific association between Lp(a) and high-risk "vulnerable" coronary plaques remained uninvestigated.
• Understanding these relationships is crucial for refining cardiovascular risk assessment.

Purpose of the Study:

• To determine if specific lipoproteins correlate with overall plaque volume and lipid deposition.
• To investigate the association between lipoproteins and the development of non-flow-limiting high-risk vulnerable plaques.
• To differentiate the roles of various lipoproteins in coronary atherosclerosis.

Main Methods:

• The PROSPECT II study utilized 3-vessel coronary artery imaging with near-infrared spectroscopy and intravascular ultrasound.
• 865 patients with recent MI underwent imaging after treatment of flow-limiting lesions.
• Associations between total cholesterol (TC), LDL-C, non-HDL-C, HDL-C, Lp(a), triglycerides, plaque volume, lipid core burden index (LCBI), and vulnerable plaque presence were analyzed.

Main Results:

• TC, LDL-C, and non-HDL-C were significantly associated with pancoronary plaque volume and LCBI (P < 0.01).
• Lp(a) was not associated with overall plaque volume or LCBI.
• Lp(a) showed a significant association with the presence of focal vulnerable plaques (P = 0.01), unlike TC, LDL-C, and non-HDL-C.

Conclusions:

• Elevated TC, LDL-C, and non-HDL-C are linked to extensive atherosclerosis and lipid deposition.
• Elevated Lp(a) is specifically associated with the presence of focal vulnerable plaques.
• These findings suggest a unique role for Lp(a) in promoting plaque vulnerability, potentially explaining its link to future MI.