Feasibility of optical coronary tomography in quantitative measurement of coronary arteries with lipid-rich plaque.

ABSTRACT

BACKGROUND: The aim of the present study was to evaluate the feasibility of optical coherence tomography (OCT) for measurement of vessel area in coronary arteries with lipid-rich plaque as compared with intravascular ultrasound (IVUS). METHODS AND RESULTS: We investigated 80 coronary artery segments with lipid-rich plaque on OCT and non-attenuated plaque on IVUS. According to the lipid arc on OCT, the plaques were classified into 4 groups group 1, lipid arc ≤90°; group 2, 90°<lipid arc≤180°; group 3, 180°<lipid arc≤270°; group 4, lipid arc >270°. Vessel circular arcs that could not be identified due to OCT signal attenuation were interpolated using an approximating algorithm. OCT-measured vessel area was well-correlated with IVUS-measured vessel area (R=0.834, P<0.001). On Bland-Altman plot, there was a good agreement between OCT-measured vessel area and IVUS-measured vessel area, although mean difference and limits of agreement increased with increase of lipid arc (mean difference in groups 1-4 -0.21, -0.31, -1.02, and -2.13 mm(2); lower limit -1.49, -3.22, -5.24, and -9.25 mm(2); and upper limit 1.07, 2.60, 3.20, and 4.99 mm(2)). Intra-observer (R=0.97-0.99, P<0.001) and inter-observer (R=0.97-0.99, P<0.001) reproducibility for OCT measurement of vessel area was excellent. CONCLUSIONS: Like IVUS, OCT can be used to measure vessel area in coronary arteries with lipid-rich plaque.