A randomized trial found that the post-PCI minimum stent area achieved after optical coherence tomography (OCT)-guided PCI was non-inferior to intravascular ultrasound (IVUS)-guided PCI. There were also no significant differences in minimum stent area between the two approaches.
The researchers added that OCT-guided PCI led to significantly greater minimum and mean stent expansion and a higher proportion of procedural success compared with angiography-guided PCI.
Lead researcher Ziad A. Ali, MD, PhD, presented the findings Oct. 30 in a late-breaking clinical trials session at the Transcatheter Cardiovascular Therapeutics scientific symposium in Washington, D.C.
Results of the trial were simultaneously published online in The Lancet. St. Jude Medical funded the study.
“These results provide further evidence of the importance of imaging in PCI procedures,” said Ali, associate director of translational medicine at the Columbia University Medical Center’s Center for Interventional Vascular Therapy, in a news release. “Minimal stent area is widely considered the most important factor for circumventing both early and late major cardiovascular events. Now we know that OCT-guided PCI achieves similar [minimum stent area] results to IVUS-guided PCI and results in significantly greater stent expansion to angiography.”
In this study, known as ILUMIEN III: OPTIMIZE PCI, the researchers enrolled patients at 29 hospitals in eight countries who were undergoing PCI with a metallic drugeluting stent for angina, silent ischemia, nonSTsegment elevation MI or recent STsegment elevation MI. They then randomized 450 patients in a 1:1:1 ratio to undergo OCTguided, IVUSguided or angiographyguided stent implantation.
The final median postPCI minimum stent area was 5.79 mm2 with OCT guidance, 5.89 mm2 with IVUS guidance and 5.49 mm2 with angiography guidance.
Untreated major dissections were found in 13.1 percent of the OCT-guided group, 18.6 percent of the angiography-guided group and 26.1 percent of the IVUS-guided group. Untreated major stent malapposition was found in 10.7 percent, 31.4 percent and 20.7 percent of patients, respectively.
“These results are encouraging, but further study is still needed to determine whether the advantages we have identified by utilizing OCT-guidance will impact clinical outcome,” Ali said in a news release.
During the study, the researchers used St. Jude Medical’s OPTIS integrated and ILLUMIEN OPTIS PCI optimization systems and the Dragonfly imaging catheters. The company plans on initiating the ILUMIEN IV trial next year that will assess long-term outcomes in a randomized trial comparing angiography-guided PCI alone versus angiography and OCT-guided PCI.
This study had a few limitations, according to the researchers, including that they did not mandate an IVUS-guided stent strategy. They also did not allow bioresorbable scaffolds. In addition, they could not mask investigators and patients.
“Demonstration of improved clinical outcomes in an adequately powered randomized trial is required before routine use of OCT guidance during stent implantation can be recommended,” the researchers wrote. “The observations in this study that external elastic laminabased OCT sizing is safe and effective in achieving noninferior stent dimensions to IVUS guidance and superior stent expansion to angiography guidance provides the foundation for the planned ILUMIEN IV clinical outcomes trial.”