OCTOBER Trial: OCT Reduces MACE in complex bifurcation lesions

By Lucas Marinacci on

Key Points

  • This trial randomizing patients with stable angina, unstable angina (UA), or non–ST-segment elevation myocardial infarction (NSTEMI) and a true bifurcation lesion to optical coherence tomography (OCT)-guided or angiography-guided percutaneous coronary intervention (PCI) found a significantly lower rate of major adverse cardiovascular events in the OCT arm at two years.
  • Results were consistent for both left main (LM) and non-LM bifurcation PCI. Secondary outcomes numerically favored OCT but did not reach statistical significance. Contrast use and procedural time was higher in the OCT arm.
  • These data support the routine use of OCT guidance for stable angina, UA, and NSTEMI involving bifurcation lesions, though patients with advanced kidney disease were excluded from this study.

Bifurcation lesions are technically challenging to fix and are at high risk of suboptimal procedural results.  PCI involving a bifurcation lesion is associated with higher mortality compared to PCI without any bifurcation intervention.1  Intravascular imaging, such as OCT, can help optimize bifurcation stent implantation. Whether routine OCT use during bifurcation stenting leads to improved clinical outcomes is unknown.

On August 27th, 2023 the results of the OCT for Angiography Guidance for PCI in Complex Bifurcation Lesions (OCTOBER) Trial were presented in a Hot Line Session at ESC Congress 2023 with simultaneous publication in the New England Journal of Medicine.

In this multicenter, randomized, open-label clinical trial, patients with stable angina, UA, or NSTEMI with a true bifurcation lesions (i.e. significant stenoses in both the main and side branches) with side branch reference size >= 2.5mm were randomized in a 1:1 fashion to OCT- or angiography guided-PCI.2  Patients with STEMI, cardiogenic shock, estimated glomerular filtration rate <50 ml/min/1.73 m2, left ventricular ejection fraction < 20%, heart failure with NYHA Class III or more were excluded, as were patients with LM thrombus or severe tortuosity or chronic total occlusion at the target lesion.  OCT-guided PCI was performed according to detailed trial protocol.   The angiography-guided arm was permitted to use intravascular ultrasound (IVUS) in cases involving the LM.  The primary outcome measure was major adverse cardiovascular events (defined as cardiac death, target lesion myocardial infarction, or ischemia-driven target lesion revascularization) at 2 years.

Overall, 1201 patients were randomized.  The mean age was 66.3 years; 21% were female.  The majority (54%) had stable angina; 13% presented with NSTEMI.  The median EF was 58%, and 42% had a prior PCI.  Nearly 20% had a LM bifurcation lesion, and 35% were treated using a one stent strategy.  About 20% of the angiography arm cases utilized IVUS.

MACE was significantly lower in the OCT-guided arm (10.1% vs. 14.1%, HR 0.70, 95% CI 0.50–0.98, p = 0.035).  Rates of the individual components of the primary endpoint were lower in the OCT arm but did not reach statistical significance.  Similarly, all-cause mortality (2.4% vs.  4.0%, 95% CI 0.28- 1.10) and stent thrombosis (2.1% vs. 3.0%, HR 0.70, 95% CI 0.34-1.47) favored OCT, however the study was not powered for these outcomes.  The OCT arm had greater contrast volume use (300cc vs 200cc). Procedure-related complications occurred in 41 patients (6.8%) in the OCT-guided PCI group and 34 patients (5.7%) in the angiography-guided PCI group.

According to principal investigator Dr. Niels Holm: “The OCTOBER trial results indicate that implementing routine OCT for guiding complex bifurcation PCI may lead to improved clinical outcomes for a group of patients with increased risk of major cardiac events after PCI.  Multiple studies have shown that OCT allows for optimization of bifurcation PCI and out results confirm that such optimization improves the patient’s prognosis.”