The OCCUPI trial, presented at the European Society of Cardiology Congress 2024, reveals that optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) significantly improves cardiovascular outcomes compared to angiography-guided PCI in patients with complex coronary lesions. The study, a multicenter, randomized, open-label trial conducted in South Korea, highlights the potential of OCT to optimize PCI procedures and reduce adverse events.
The trial enrolled 1,604 patients with ischemic heart disease and complex coronary lesions, randomizing them to either OCT-guided PCI (n=803) or angiography-guided PCI (n=801). Complex lesions included acute myocardial infarction (AMI), chronic total occlusion, long lesions (≥28 mm), calcified lesions, bifurcation lesions, unprotected left main disease, small vessel disease (<2.5 mm), intracoronary thrombus, stent thrombosis, in-stent restenosis, and bypass graft lesions. The primary endpoint was major adverse cardiac events (MACE), defined as cardiac death, ischemia-driven target lesion revascularization (ID-TLR), myocardial infarction (MI), or stent thrombosis at 12 months.
Key Findings
The primary endpoint of MACE occurred in 5% of patients in the OCT-guided PCI group compared to 7% in the angiography-guided PCI group (HR 0.62, 95% CI 0.41-0.938, p = 0.023). This significant reduction was primarily driven by a lower rate of ID-TLR in the OCT-guided group (2% vs. 4%, HR 0.36, 95% CI 0.18-0.69, p = 0.0022).
Other components of MACE, including cardiac death (HR 0.20, 95% CI 0.03-1.71, p = 0.14), MI (HR 0.72, 95% CI 0.45-1.16, p = 0.18), and stent thrombosis (p = 0.12), did not show statistically significant differences between the two groups.
Secondary outcomes revealed that OCT-guided PCI was associated with greater contrast volume use (300 vs. 210 cc, p < 0.0001) and longer procedure duration (53 vs. 43.5 minutes, p < 0.0001). All-cause mortality and contrast-induced nephropathy rates were similar between the groups.
Implications for Clinical Practice
The OCCUPI trial adds to the growing body of evidence supporting the use of image-guided PCI, particularly in complex lesions. According to the researchers, the findings suggest that OCT guidance can optimize stent deployment by ensuring adequate stent expansion, apposition, and edge dissection. Acceptable stent expansion was defined when minimal stent area was ≥80% of the mean reference lumen area, ≥100% of the distal reference lumen area, or absolute minimal stent area was >4.5 mm2 (for a non–left main lesion). Acceptable stent apposition was indicated by an acute stent malapposition <400 μm. Acceptable edge dissection was defined as the absence of major dissection (defined as a circumference of the vessel at the site of dissection with an arc of ≥60°, length of dissection ≥3 mm, or deeper vessel injury). Stent optimization was defined when the acceptable criteria of these three components were met.
While the increased contrast use and longer procedural times associated with OCT-guided PCI may be a consideration for patients with advanced chronic kidney disease, the trial suggests that the benefits of reduced MACE and ID-TLR outweigh these drawbacks in the broader population of patients with complex coronary lesions.
The OCCUPI trial's results align with findings from the OCTOBER trial, which demonstrated the superiority of OCT-guided PCI in bifurcation PCI. However, they contrast with the ILLUMEN IV trial, where routine OCT-guided PCI was not superior to angiography-guided PCI, although a benefit was observed in the complex PCI subset, similar to the OCCUPI trial population.
