OCT- vs angiography-guided PCI for bifurcation lesions: Which is better?

In percutaneous coronary intervention (PCI) for complex bifurcation lesions, optical coherence tomography (OCT) guidance outdid the angiography-guided approach, findings from the OCTOBER* trial have shown.

“OCT is a newer high-resolution intravascular imaging modality that has been shown to allow for optimization of procedural PCI results, which might be of particular value in bifurcation PCI,” said Dr Lene Nyhus Andreasen from Aarhus University Hospital, Denmark, at ESC 2023.

“OCTOBER demonstrated that in patients with complex bifurcation lesions, OCT-guided PCI was associated with better outcomes after 2 years than angiography-guided PCI,” she continued.

The incidence of the primary endpoint of MACE** was lower in the OCT vs the angiography arm (10.1 percent vs 14.1 percent; hazard ratio [HR], 0.70; p=0.035). [ESC 2023, Hot Line 4 session]

OCT consistently favoured angiography across all secondary endpoints, namely cardiac death (1.4 percent vs 2.6 percent; HR, 0.53), ischaemia-driven target lesion revascularization (2.8 percent vs 4.6 percent; HR, 0.60), target lesion MI (7.8 percent vs 8.5 percent; HR, 0.90), PoCE*** (13.6 percent vs 17.7 percent; HR, 0.76), and all-cause mortality (2.4 percent vs 4.0 percent; HR, 0.56). OCT also trumped angiography across most subgroups.

Of note, the trial was not powered for the secondary endpoints hence the lack of statistical significance.

 

Complex treatment approach warranted

“True bifurcation lesions are associated with technical difficulties and worse prognosis than non-true bifurcations. They may require more complex treatment strategies,” said Andreasen. Though standard practice requires angiographic guidance in PCI, angiographic ambiguity is high with bifurcation lesions.

“This is a particular issue during complex bifurcation PCI,” she continued. As such, Andreasen and her team sought to evaluate whether stepwise guidance by OCT would improve outcomes following PCI of true bifurcation lesions as opposed to angiography-guided PCI.

The team evaluated 1,201 patients (mean age 66 years, 79 percent male) from 38 heart centres in Europe who had stable angina (>50 percent), unstable angina, or NSTEMI^#. They were randomized 1:1 to OCT- or angiography-guided PCI.

In the angiography arm, OCT was not allowed. Though not encouraged, other patients had some level of IVUS^##-guided PCI for left main lesions. “This reflects current clinical practice for complex PCI procedures in many centres,” Andreasen noted. Stent implantation was done as per usual practice.

 

A safe but longer procedure

The incidence of procedure-related complications^### was slightly higher in the OCT vs angiography arm (6.8 percent vs 5.7 percent) but procedure-related MI was lower (5.7 percent vs 7.0 percent; HR, 0.79).

“Procedures using OCT guidance were safe but took longer, and more contrast was used,” said Andreasen. With OCT, median procedural time was 113 minutes while median fluoroscopy time was 27 minutes. With angiography, the corresponding times were 80 and 22 minutes, respectively. Median total contrast volume with OCT was greater than angiography by 100 mL.

 

Addressed an unmet need

“The results suggest that routine use of structured OCT guidance during PCI of complex bifurcation lesions should be considered to improve prognosis,” said Andreasen.

Discussant Dr Fernando Alfonso Manterola from the Universidad Autónoma de Madrid, Spain commended the OCTOBER team for “using a predefined OCT strategy before stenting, after stenting and rewiring, and having a final evaluation looking for optimal lesion coverage and stent expansion, and to rule out malapposition and major distortion of the stent.”

“This trial addressed an unmet clinical need, which is the treatment of complex bifurcations involving major branches,” Manterola continued. The study was completed, had a large sample size with only a few patients lost to follow-up, few exclusion criteria, and every individual endpoint went in the same direction, with no formal interaction identified on subgroup analysis, he added.

“OCTOBER is the best study currently available on the value of coronary imaging to optimize treatment of bifurcation lesions. The findings should impact clinical practice,” said Manterola.