麻豆传媒

WASHINGTON -- Using optical coherence tomography (OCT) to guide percutaneous coronary intervention (PCI) didn't lead operators to undersize stents compared with intravascular ultrasound (IVUS), the randomized ILUMIEN III: OPTIMIZE PCI study found.

With a standardized OCT strategy for stent sizing based on pre-intervention OCT measurements of external elastic lamina, to overcome the problem of incomplete vessel wall visualization, in the cath lab (median 5.79 versus 5.89 mm², P_inferiority=0.001).

OCT was not superior to minimum stent area after angiography, the go-to for most operators (P=0.12), reported , of New York-Presbyterian Hospital/Columbia University Medical Center, at the annual Transcatheter Cardiovascular Therapeutics meeting and online in The Lancet.

However, OCT led to greater stent expansion (16.6% versus 12.9%, P=0.02) and acute procedural success (P<0.05) than did angiography as well as fewer untreated major dissections (14% versus 26%, P=0.009) and cases of malapposition (11% versus 21%, P=0.02) than with IVUS guidance, Ali's group noted.

"These data warrant a large-scale randomized trial to establish whether or not OCT guidance results in superior clinical outcomes to angiography guidance," the authors wrote.

"Although this finding certainly appears to be important, the clinical significance of these imaging-detected complications remains to be further elucidated. Indeed, use of potential surrogate measures of clinical outcomes (the primary measure and focus of this study) should be viewed with caution," argued , and , both of Australia's Royal North Shore Hospital.

"The notion of changing management by a strategy such as OCT because of its ability to detect suboptimal stent deployment is based on perceived issues or problems rather than real validated prospective clinical outcomes. This putative advantage has been speculated as a benefit for years, yet has not translated into any meaningful clinical result yet," they wrote in an .

Procedural major adverse cardiac events occurred in 3% of OCT, 1% of IVUS, and 1% angiography cases (P=0.37 for difference between OCT and IVUS/angiography) in ILUMIEN III: OPTIMIZE PCI, which included 450 patients randomized to OCT, IVUS, or angiography for guidance of stenting done between 2015 and 2016 at 29 hospitals in eight countries.

The external elastic lamina measurement that was the proposed basis for sizing by OCT was measured by operators in 85% of cases and actually used for sizing only in 75% of cases, Bhindi and Allahwala commented. "Furthermore, operators using this technique had considerable expertise in intravascular imaging, meaning its broad applicability is unknown."

The editorialists suggested weighing the potential benefit of increasing minimum stent area against the negatives of OCT, "including disruption of plaques in vessels during imaging, patients having longer procedures with more contrast than with angiography alone, and the obvious extra cost to the patient, insurer, and health-care system."

"Although this study strengthens the evidence for intracoronary OCT use, whether or not it should be used routinely in all cases remains unclear and in this regard, is therefore still not ready for widespread use and further clinical outcome-based studies are necessary," Bhindi and Allahwala concluded.