ILUMIEN-4 and OCTOBER in detail
Conducted at 80 centers in 18 countries, ILUMIEN-4 randomly assigned patients with diabetes or complex coronary lesions to undergo PCI guided by OCT or using standard angiography only, 1,233 and 1,254 patients, respectively.
Post-PCI MSA averaged 5.72 mm2 with OCT guidance and 5.36 mm2 in the angiography-only group (P < .001).
Their rates of target-vessel failure at 2 years were not significantly different at 7.4% and 8.2%, respectively. The 2-year composite endpoint included cardiac death, target vessel–related MI, or ischemia-driven target-vessel revascularization.
Definite or probable stent thrombosis was observed over 2 years in 0.5% of the OCT group and 1.4% of those with angiography-only PCI (hazard ratio, 0.36; 95% confidence interval, 0.14-0.91; P = .02) favoring OCT.
The OCTOBER trial, conducted at 38 centers in Europe, entered 1201 patients with stable angina or acute coronary syndromes and angiographically identified complex bifurcation lesions. They involved the left-main coronary artery in about one-fifth of cases.
Patients were randomly assigned to bifurcation PCI guided by OCT or under standard angiography, 600 and 601 patients, respectively. Rates for procedure-related complications were similar at 6.8% and 5.7%, respectively.
Over a median of 2 years, 10.1% of the OCT group and 14.1% of angiography-only patients developed a MACE event, including cardiac death, target-lesion MI, or ischemia-driven target-lesion revascularization. The adjusted HR was 0.71 (95% CI, 0.51-0.98; P = .035) in favor of OCT.
Meta-analysis, trials to date
The meta-analysis presented by Dr. Stone included ILUMIEN-4, OCTOBER, and 18 earlier outcomes trials comparing PCI guided by IVI, either OCT or IVUS, and angiography-only PCI. It covered 12,428 patients with chronic or acute coronary disease and followed them a mean of 26 months; the longest follow-up was 5 years. They were assigned to IVI-guided or angiography-only PCI, 7,038 and 5,390 patients, respectively.
Dr. Stone and colleagues conducted a network meta-analysis of the 20 studies, that is, a combined analysis that allowed both direct and indirect comparisons of standard angiography-only procedures to each of the other studied comparator interventions including OCT, IVUS, and either OCT or IVUS. They then derived network-estimate odds ratios for IVI-guided PCI vs angiography-only procedures.
“Hopefully, this will impact the guidelines,” Dr. Stone said of the meta-analysis. Procedures guided by IVI might become more common in clinical practice if they were to garner a Class-I guideline recommendation, the strongest recommendation category.
“That would make a difference, but we’d also need to work to remove impediments to increasing intravascular imaging guidance” for most patients undergoing PCI, he said, referring to challenges in obtaining reimbursement for IVI-guided PCI and training enough operators to handle the projected demand.
ILUMIEN-4 was funded by Abbott. OCTOBER was supported by grants from Abbott Vascular, St. Jude Medical, and Aarhus University. The network meta-analysis received statistical support from Abbott. Dr. Ali disclosed institutional grant support from Abbott, Abiomed, Acist Medical, Boston Scientific, Cardiovascular Systems, Medtronic, the National Institutes of Health, Opsens Medical, Philips, and Teleflex; consulting fees from Astra Zeneca, Philips, Shockwave; and holding equity in Elucid, Spectrawave, Shockwave, and VitalConnect. Dr. Holm and Dr. Bhatt reported numerous conflicts of interest. Dr. Andreasen disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.