Discrepancy between frequency domain optical coherence tomography and intravascular ultrasound in human coronary arteries and in a phantom in vitro coronary model

Abstract

Background.

This purpose of this study is to evaluate, concomitantly with quantitative coronary angiography (QCA), the potential discrepancy between frequency domain optical coherence tomography (FD-OCT) and intravascular ultrasound (IVUS) measurements in a phantom coronary model and in human coronary arteries within and outside stented segments.

Methods.

FD-OCT and IVUS images sequentially obtained from a phantom coronary model and 57 stented human coronary arteries were compared between each other and with QCA.

Results.

Lumen area (LA) by IVUS was 10.1% larger (6.43 ± 0.09 mm2) while by FD-OCT was similar (5.78 ± 0.09 mm2) to actual phantom LA (5.72 mm2); IVUS vs. FD-OCT stent area (SA) was 4.2% larger. In human coronary artery, diameter by QCA was smaller than by IVUS and OCT in reference (by 10.5% and 3.5%, both p < 0.001) and stented (3.6%, p < 0.001; and 1.7%, p = 0.012) segments. IVUS vs. FD-OCT distal reference LA was significantly larger (6.19 ± 2.18 mm2 vs. 5.49 ± 2.49 mm2, p < 0.001, respectively), and SA was numerically larger (7.42 ± 2.28 mm2 vs. 7.22 ± 2.48 mm2, p = 0.059) with larger discrepancy in reference (11.3%) than stented (2.7%) segments. IVUS vs. FD-OCT correlation for diameter was significantly higher for stented than reference segments (R2 = 0.8670 vs. 0.7351, p = 0.047), while numerically higher for area (R2 = 0.8663 vs. 0.7806, p = 0.157).

Conclusions.

In phantom model and human coronary arteries, IVUS vs. FD-OCT measurements were larger, particularly in non-stented than stented segments, and diameter was smaller by QCA vs. IVUS or FD-OCT. Despite undefined clinical significance, said discrepancy warrants consideration.