Analysis compares stent expansion achieved with guidance from optimal coherence tomography versus intravascular ultrasound

Data from the ILUMIEN II trial found that guidance from optimal coherence tomography (OCT) was associated with comparable stent expansion as guidance from intravascular ultrasound (IVUS) in patients undergoing percutaneous coronary intervention (PCI). Coronary stents must be optimally deployed with full lesion coverage and complete stent expansion to optimize outcomes. Less than full expansion can result in stent thrombosis or restenosis. Previous studies have found that the strongest predictor of stent thrombosis and restenosis is the minimum stent area (MSA) achieved after PCI.
Advanced imaging techniques, such as IVUS and OCT, help cardiologists to measure, place, and expand the stent with optimal precision. By achieving greater stent luminal dimensions, IVUS-guidance has been associated with improved event-free survival compared to angiographic guidance alone. Compared to IVUS, OCT has superior resolution but does not penetrate as deeply into the arterial wall. Consequently it has limitations in assessing the true diameter of the native artery. It is unknown whether stent expansion, a surrogate of clinical outcomes, is as great with OCTguidance as with IVUS-guidance.
ILUMIEN II was a prospectively planned, retrospective comparison of OCT-guidance in ILUMIEN I and IVUS-guidance in ADAPT-DES. The overall study population initially included a total of 940 patients (one lesion randomly chosen per patient; 354 from ILUMIEN I and 586 from ADAPTDES). Aft er 1:1 propensity matching, 286 patients/lesions from each group were analyzed (n=572).Both the OCT and IVUS analyses were performed by the CRF Clinical Trials Center.
The primary endpoint was post-PCI stent expansion (%) defined as the minimum stent area (MSA) divided by the mean reference lumen area as assessed by OCT in ILUMIEN I and by IVUS in ADAPT-DES. The secondary endpoints were the following IVUS and OCT core lab measures:
Mean stent expansion (defined as stent volume/stent length divided by the mean reference lumen area);
Prevalence of major edge dissection (≥3 mm in length); Prevalence of major stent malapposition (malapposition distance/luminal diameter ≥20%). The secondary endpoint using angiographic core lab measures (independent of technique) was post-PCI mean lumen diameter (MLD), percent diameter stenosis, and acute gain.
The post-PCI stent expansion was 72.8% [63.3, 81.3] in the OCT-guided group compared to 70.6% [62.3, 78.8] in the IVUSguided group (p=0.29). Similar rates of major stent edge dissection (2.4% vs. 1.0%, p=0.29) and major stent malapposition (1.4% vs. 0.7%, p=0.69) occurred in both groups.