Coronary disease & ACSSecondary analysis

Optical coherence tomography versus angiographic guidance in true unprotected left main bifurcation disease: an OCTOBER substudy

EuroInterventionPublished

  • OCTOBER substudy
  • randomised to either optical coherence tomography (OCT) or angiographic guidance in the OCTOBER Trial

Authors' conclusion

OCT-guided PCI in true LMCA bifurcation lesions was clinically feasible, but visibility of the LMCA ostium was limited by short pullbacks, insufficient clearance, or guide catheter shadowing. OCT guidance was associated with a non-significant reduction in MACE, consistent with the effect estimate in the main trial.

Study context

Population
Patients with true unprotected left main coronary artery (LMCA) bifurcation lesions undergoing percutaneous coronary intervention (PCI)patients included · OCT 111 · angiography 116
Participants
227 patients
Comparison
OCT guidance compared with angiographic guidance in PCI of true LMCA bifurcation lesions
  • OCTn = 111
  • angiographyn = 116reference

Primary result

As reported in the abstract

Major adverse cardiac events (MACE):
  • Cardiac death
  • Any myocardial infarction
  • Target lesion revascularisation

Hazard ratio

0.78

95% CI 0.39–1.51

By group

OCT vs angiography
hazard ratio 0.78 (95% CI 0.39–1.51)

Further findings

Feasibility of OCT guidance (successful pullbacks, as per protocol)

Pre-stenting pullback performed
98%
Final pullback performed
96%

Analysability of the proximal LMCA stent edge

Proximal LMCA stent edge analysable
43%
Not analysable
57%
Of the remaining 57% (not analysable), limited by insufficient image quality
5%

Original publication

Optical coherence tomography versus angiographic guidance in true unprotected left main bifurcation disease: an OCTOBER substudy. EuroIntervention. Published 15 May 2026. doi:10.4244/eij-d-25-01337

Summarised from the published abstract; every number is checked against it