The vulnerable artery: early and rapid deposition of lipid in coronary arteries is associated with subsequent development of thin-cap fibroatheromas.

Aims: We aimed to determine whether intravascular ultrasound (IVUS) and near infrared spectroscopy (NIRS) could identify arteries which would subsequently develop a thin-cap fibroatheroma (TCFA). Methods and results: Three-vessel angiography, IVUS and NIRS evaluations were performed at three, six and nine months after induction of diabetes mellitus and hypercholesterolaemia in 13 Yorkshire pigs (n=37 arteries). In vivo total arterial plaque plus media (P+ M) area, echo-attenuated plaque (AP) area by IVUS, and lipid core burden index (LCBI) by NIRS were compared to histology at nine months. P+ M mean area increased over time (3 vs. 6 months p<0.01; 6 vs. 9 months p<0.01), as did the AP area and mean LCBI between three and six months (p<0.01). There were 69 TCFAs within 18 arteries. The mean LCBI at six months was greater in arteries containing a TCFA (77.8 +/- 17.4 vs. 34.3 +/- 11.4; p=0.04) as was the.LCBI from three to six months (55.3 +/- 16.9 vs. 3.3 +/- 16.0; p=0.03). Arteries which contained TCFA at nine months had greater AP area by IVUS at six months (p=0.007). Conclusions: The early and persistent accumulation of total arterial lipid detected by NIRS was associated with the future development of TCFAs.