Masaru Ishida, Yoshihiro Morino, et al
According to previous studies, the presence of coronary calcification was associated with worse clinical outcomes due to plaque fracture after angioplasty and stent underexpansion. It remained the biggest issue even after the emergence of drug-eluting stents (DES). Intravascular ultrasound (IVUS) played an important role in the evaluation of coronary calcification during percutaneous coronary intervention (PCI). However, due to limited resolution and inevitable artefacts such as acoustic shadowing and side lobes, only the arc or the “approximate” degree of superficiality of coronary calcifications could be assessed. Currently, optical coherence tomography (OCT), another intravascular imaging technique with a higher spatial resolution, has become applicable in the clinical setting. It can visualise and delineate coronary calcification without attenuation or side lobe artefacts. Thus, unlike IVUS, we can measure thickness, depth and the arc of the cluster of calcium as well as accurate luminal dimensions10 using this modality. Considering such performance and superiority, detailed investigations regarding coronary calcification and its substantial impact on lumen expansion by PCI can be performed and have been demanded. Therefore, the present study was designed to: 1) evaluate geographic and morphological features of coronary calcification, and 2) investigate the relationship between measurable components of calcification and stent expansion in a consecutive series of patients. The results obtained will give us new insights into coronary calcification and vessel expansion.