Aims: We aimed to compare intravascular ultrasound with virtual histology (VH-IVUS), optical coherence tomography (OCT) and near-infrared spectroscopy (NIRS) for their ability to quantify the true amount and characterise the nature of released plaque material during bioresorbable vascular scaffold (BVS) implantation into right coronary artery (RCA) lesions using a distal occlusion and aspiration device.
Methods and results: Seventeen patients underwent BVS implantation into the right coronary artery under distal protection with intracoronary imaging using VH-IVUS, OCT and NIRS. The amount of released plaque material and its lipid content (LC) were determined. Necrotic core volume and minimal fibrous cap thickness correlated with the amount of released plaque material (r=0.80 and r=-0.65, respectively) and its LC (r=0.75 and r=-0.78, respectively), but not maximal lipid core burden index (LCBI). OCT-identified thin-cap fibroatheromata (TCFA) were associated with the greatest amount of released plaque material compared to non-TCFA (46.8 [29.0;49.2] mg vs. 14.2 [11.3;19.4] mg; p=0.003) and LC (4.4 [4.0;4.8] mg vs. 2.0 [1.8;2.5] mg; p=0.000).
Conclusions: VH-IVUS and OCT but not NIRS parameters quantify and characterise the amount of released plaque material. TCFA is associated with the highest amount of released plaque material and may therefore benefit from the use of protection devices.