ABSTRACT

In addition, several angioscopic studies6,8-10 have suggested that variations in yellow color intensity may reflect differences in the vulnerability of plaques. Uchida et al.6 performed a three-vessel angioscopic examination in 157 patients with stable angina, and followed the patients prospectively for 12 months. Acute coronary syndromes occurred more frequently in patients with yellow plaques than in those with white plaques (28.2% vs. 3.3%, p = 0.00021). Moreover, among patients with yellow plaques, acute coronary syndromes occurred more frequently in those with glistening yellow plaques than in those with non-glistening yellow plaques (68.4% vs. 7.6%; p = 0.00026). In a study by Ueda et al.8 including 843 patients, angioscopy of the culprit artery revealed a total of 1253 yellow plaques in the angiographically non-stenotic segments. The yellow color intensity was categorized as light yellow (n = 345), moderate yellow (n = 721) and glistening yellow (n = 187). The prevalence of thrombus detected by angioscopy was significantly higher according to the increased intensity of yellow color: 15% in light yellow, 26% in moderate yellow and 52% in glistening yellow, respectively; p < 0.0001. Takano et al.10 demonstrated that lipid-lowering therapy with atorvastatin resulted in the reduction of angioscopic yellow color intensity and complexity of coronary plaques such as surface irregularity, which implies a relationship between the yellow color intensity and differences in plaque stability.