Abstract 3060: Assessment of Coronary Red and White Thrombus by Optical Coherence Tomography
[BACKGROUND] Recently, OCT has been proposed as a high-resolution imaging modality. However, the OCT appearance of thrombi in vivo has not been well described. We sought to analyze the optical coherence tomography (OCT) characteristics of different types of coronary thrombi confirmed by coronary angioscopy (CAS).
[METHODS and RESULTS] We examined 41 intra-coronary thrombi of 22 patients with acute myocardial infarction. After identification of red or white thrombi by CAS, OCT images were obtained and analyzed signal intensity property of both thrombi. The proportion of red and white thrombi was 56% and 44%, respectively. Red thrombi were identified as high-backscattering mass protruding into the artery lumen, with signal-free shadowing in the OCT image. White thrombi were identified as low-backscattering projections within the lumen in the OCT image. There were no significant differences in the peak intensity of the OCT signal between red and white thrombi (127 +/− 32 vs. 134 +/− 38, p=0.728). However the half attenuation width of the signal intensity curve, which was defined as the distance from the peak intensity to its half intensity, was quite significantly different between red and white thrombi (177 +/− 72 vs. 346 +/− 59 micrometer, p<0.001). Cutoff value of 210μm in the half width of signal intensity attenuation can differentiate red thrombi from white thrombi with the sensitivity of 87%, the specificity of 94%, the positive predictive value of 95% and negative predictive value of 84%.
[CONCLUSIONS] We present the first detailed description of the characteristics of different types of coronary thrombi in vivo in OCT images. Intracoronary OCT may allow us not only to estimate plaque morphology but also to distinguish between red and white thrombi.