Optical coherence tomography-guided coronary stent implantation compared to angiography: a multicentre randomised trial in PCI – design and rationale of ILUMIEN IV: OPTIMAL PCI

Aims Randomised trials have demonstrated improvement in clinical outcomes with intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI. The ILUMIEN III trial demonstrated non-inferiority of an optical coherence tomography (OCT)- versus IVUS-guided PCI strategy in achieving similar post-PCI lumen dimensions. ILUMIEN IV is a large-scale, multicentre, randomised trial designed to demonstrate the superiority of OCT- versus angiography-guided stent implantation in patients with high-risk clinical characteristics (diabetes) and/or complex angiographic lesions in achieving larger post-PCI lumen dimensions and improving clinical outcomes. Methods and results ILUMIEN IV is a prospective, single-blind clinical investigation that will randomise between 2,490 and 3,656 patients using an adaptive design to OCT-guided versus angiography-guided coronary stent implantation in a 1:1 ratio. The primary endpoints are: (1) post-PCI minimal stent area assessed by OCT in each randomised arm, and (2) target vessel failure, the composite of cardiac death, target vessel myocardial infarction, or ischaemia-driven target vessel revascularisation. Clinical follow-up will continue for up to two years. The trial is currently enrolling, and the principal results are expected in 2022. Conclusions The large-scale ILUMIEN IV randomised controlled trial will evaluate the effectiveness of OCT-guided versus angiography-guided PCI in improving post-PCI lumen dimensions and clinical outcomes in patients with diabetes and/or with complex coronary lesions. Trial registration NCT03507777.