Implication of plaque color classification for assessing plaque vulnerability: a coronary angioscopy and optical coherence tomography investigation.
OBJECTIVE
The purpose of this study was to assess the relationship between plaque color evaluated by coronary angioscopy and fibrous cap thickness estimated by optical coherence tomography (OCT) in vivo.


BACKGROUND
Yellow color intensity of coronary plaque evaluated by coronary angioscopy might be associated with plaque vulnerability.


METHODS
Seventy-seven coronary artery plaques in patients with acute coronary syndrome were observed by angioscopy and OCT. Plaque color was graded as white, light yellow, yellow, or intensive yellow.


RESULTS
There were significant differences among the groups classified by plaque color with respect to the fibrous cap thickness estimated by OCT: 389 +/- 74 mum in white plaques, 228 +/- 51 microm in light yellow plaques, 115 +/- 28 microm in yellow plaques, and 59 +/- 14 microm in intensive yellow plaques (p < 0.0001). In Spearman rank-order correlation analysis, there was a significant negative correlation between yellow color intensity and fibrous cap thickness (p < 0.0001). Furthermore, 80% of intensive yellow plaques were thin cap fibroatheroma with a cap thickness of < or =65 microm.


CONCLUSIONS
The plaque color in coronary angioscopy was determined by the fibrous cap thickness, which was assessed by OCT. Although coronary angioscopy remains a specialized research tool, it might allow us to evaluate plaque vulnerability.
Kubo
Takashi
T
Department of Cardiovascular Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Japan.
Imanishi
Toshio
T
Takarada
Shigeho
S
Kuroi
Akio
A
Ueno
Satoshi
S
Yamano
Takashi
T
Tanimoto
Takashi
T
Matsuo
Yoshiki
Y
Masho
Takashi
T
Kitabata
Hironori
H
Tanaka
Atsushi
A
Nakamura
Nobuo
N
Mizukoshi
Masato
M
Tomobuchi
Yoshiaki
Y
Akasaka
Takashi
T
D054058:Acute Coronary Syndrome / Q000145:classification* / Q000175:diagnosis; D000368:Aged; D017546:Angioscopy / Q000379:methods*; D050197:Atherosclerosis / Q000145:classification* / Q000175:diagnosis; D003331:Coronary Vessels / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D041623:Tomography, Optical Coherence / Q000379:methods*