OCT Compared With IVUS and Angiography to Guide Coronary Stent Implantation (ILUMIEN III: OPTIMIZE PCI)

When a cardiologist places a stent, the question is how well to see what they are doing. Plain angiography shows a silhouette; intravascular imaging shows the artery wall from the inside. This trial pitted two such tools — optical coherence tomography and intravascular ultrasound — against each other and against angiography alone.

Across 450 patients, OCT-guided stenting achieved a final stent expansion that was non-inferior to IVUS guidance. But it was not superior — not to IVUS, and not even convincingly to angiography on the primary measure. The headline was reassurance: OCT, with its very high resolution, is a safe and capable way to optimize a stent, on par with the established ultrasound approach.

The result is meaningful for interventional cardiologists choosing between imaging modalities, but its reach is narrow. It compared a procedural surrogate — how well the stent was expanded — rather than whether patients lived longer or had fewer heart attacks.

We rate the evidence strong as a randomized comparison, with modest clinical significance. It established OCT as a legitimate alternative to IVUS for guiding stent placement, a technical advance rather than a change in who gets treated or why.