Relation of C-reactive protein to coronary plaque characteristics on grayscale, radiofrequency intravascular ultrasound, and cardiovascular outcome in patients with acute coronary syndrome or stable angina pectoris (from the ATHEROREMO-IVUS Study)

The relation between C-reactive protein (CRP) and coronary atherosclerosis is not fully understood. This study aims to investigate the associations among high-sensitivity CRP, coronary plaque burden, and the presence of high-risk coronary lesions as measured by intravascular ultrasound (IVUS) and 1-year cardiovascular outcome. Between 2008 and 2011, grayscale and virtual histology IVUS imaging of a nonculprit coronary artery was performed in 581 patients who underwent coronary angiography for acute coronary syndrome (ACS) or stable angina pectoris. Primary end point consisted of 1-year major adverse cardiac events (MACEs), defined as all-cause mortality, ACS, or unplanned coronary revascularization. After adjustment for established cardiac risk factors, baseline CRP levels were independently associated with higher coronary plaque burden (p = 0.002) and plaque volume (p = 0.002) in the imaged coronary segment. CRP was also independently associated with the presence of large lesions (plaque burden ≥70%; p = 0.030) but not with the presence of stenotic lesions (minimal luminal area ≤4.0 mm² p = 0.62) or IVUS virtual histology-derived thin-cap fibroatheroma lesions (p = 0.36). Cumulative incidence of 1-year MACE was 9.7%. CRP levels >3 mg/L were independently associated with a higher incidence of MACE (hazard ratio 2.17, 95% confidence interval [CI] 1.01 to 4.67, p = 0.046) and of all-cause mortality and ACS only (hazard ratio 3.58, 95% CI 1.04 to 13.0, p = 0.043), compared with CRP levels <1 mg/L. In conclusion, in patients who underwent coronary angiography, high-sensitivity CRP is a marker of coronary plaque burden but is not related to the presence of virtual histology-derived thin-cap fibroatheroma lesions and stenotic lesions. CRP levels >3 mg/L are predictive for adverse cardiovascular outcome at 1 year.