Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies

Objectives: The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving the diagnosis and treatment of patients with atherosclerosis, including coronary artery disease. Background: Intravascular optical coherence tomography (IVOCT) is a catheter-based modality that acquires images at a resolution of ∼10 μm, enabling visualization of blood vessel wall microstructure in vivo at an unprecedented level of detail. IVOCT devices are now commercially available worldwide, there is an active user base, and the interest in using this technology is growing. Incorporation of IVOCT in research and daily clinical practice can be facilitated by the development of uniform terminology and consensus-based standards on use of the technology, interpretation of the images, and reporting of IVOCT results. Methods: The IWG-IVOCT, comprising more than 260 academic and industry members from Asia, Europe, and the United States, formed in 2008 and convened on the topic of IVOCT standardization through a series of 9 national and international meetings. Results: Knowledge and recommendations from this group on key areas within the IVOCT field were assembled to generate this consensus document, authored by the Writing Committee, composed of academicians who have participated in meetings and/or writing of the text. Conclusions: This document may be broadly used as a standard reference regarding the current state of the IVOCT imaging modality, intended for researchers and clinicians who use IVOCT and analyze IVOCT data

Feasibility of combined use of intravascular ultrasound radiofrequency data analysis and optical coherence tomography for detecting thin-cap fibroatheroma

Aims: To evaluate the feasibility of the combined use of virtual histology (VH)-intravascular ultrasound (IVUS) and optical coherence tomography (OCT) for detecting in vivo thin-cap fibroatheroma (TCFA). Methods and results: In 56 patients with angina, 126 plaques identified by IVUS findings were analysed using both VH-IVUS and OCT. IVUS-derived TCFA was defined as an abundant necrotic core (>10% of the cross-sectional area) in contact with the lumen (NCCL) and %plaque-volume >40%. OCT-derived TCFA was defined as a fibrous cap thickness of <65 μm overlying a low-intensity area with an unclear border. Plaque meeting both TCFA criteria was defined as definite-TCFA. Sixty-one plaques were diagnosed as IVUS-derived TCFA and 36 plaques as OCT-derived TCFA. Twenty-eight plaques were diagnosed as definite-TCFA; the remaining 33 IVUS-derived TCFA had a non-thin-cap and eight OCT-derived TCFA had a non-NCCL (in discord with NCCL visualized by VH-IVUS, mainly due to misreading caused by dense calcium). Based on IVUS findings, definite-TCFA showed a larger plaque and vessel volume, %plaque-volume, higher vessel remodelling index, and greater angle occupied by the NCCL in the lumen circumference than non-thin-cap IVUS-derived TCFA. Conclusion: Neither modality alone is sufficient for detecting TCFA. The combined use of OCT and VH-IVUS might be a feasible approach for evaluating TCFA

A randomised comparison of novolimus-eluting and zotarolimus-eluting coronary stents: 9-Month follow-up results of the EXCELLA II study

Aims: Novolimus, a macrocyclic lactone with anti-proliferative properties, has a similar efficacy to currently available agents; however it requires a lower dose, and less polymer, and is therefore conceivably safer. Methods and results: The EXCELLA II study was a prospective, multicentre, single-blind, non-inferiority clinical trial which randomised 210 patients with a maximum of two de novo coronary artery lesions in two different epicardial vessels in a ratio of 2:1 to treatment with either the Elixir DESyne Novolimus Eluting Coronary Stent System (NES n=139, Elixir Medical, Sunnyvale, CA, USA) or the Endeavor zotarolimus eluting stent (ZES n=71, Medtronic, Santa Rosa, CA, USA). The primary endpoint was in-stent mean late lumen loss (LLL) at 9-months follow-up. In-stent percent volume obstruction (%VO) was measured in a sub-group of 65 patients having 9-month intravascular ultrasound (IVUS) follow-up. Clinical secondary endpoints included a device orientated composite of cardiac death, target vessel myocardial infarction (MI), and clinically indicated target lesion revascularisation (CI-TLR) assessed at 9-months follow-up. At 9-months, the in-stent LLL was 0.11±0.32 mm in the NES arm, as compared to 0.63±0.42 mm in the ZES (p<0.0001 non-inferiority, p<0.0001 superiority). In-stent%VO was 4.5±5.1% and 20.9±11.3% for NES and ZES, respectively (p<0.001). There was no significant difference between stent groups in the device orientated composite endpoint (NES 2.9% vs. ZES 5.6%, -2.8% [-8.8%, 3.3%], p=0.45) or its indi