Randomised comparison of provisional side branch stenting versus a two-stent strategy for treatment of true coronary bifurcation lesions involving a large side branch: the Nordic-Baltic Bifurcation Study IV

Abstract

Background: It is still uncertain whether coronary bifurcations with lesions involving a large side branch (SB) should be treated by stenting the main vessel and provisional stenting of the SB (simple) or by routine two-stent techniques (complex). We aimed to compare clinical outcome after treatment of lesions in large bifurcations by simple or complex stent implantation.

Methods: The study was a randomised, superiority trial. Enrolment required a SB≥2.75 mm, ≥50% diameter stenosis in both vessels, and allowed SB lesion length up to 15 mm. The primary endpoint was a composite of cardiac death, non-procedural myocardial infarction and target lesion revascularisation at 6 months. Two-year clinical follow-up was included in this primary reporting due to lower than expected event rates.

Results: A total of 450 patients were assigned to simple stenting (n=221) or complex stenting (n=229) in 14 Nordic and Baltic centres. Two-year follow-up was available in 218 (98.6%) and 228 (99.5%) patients, respectively. The primary endpoint of major adverse cardiac events (MACE) at 6 months was 5.5% vs 2.2% (risk differences 3.2%, 95% CI -0.2 to 6.8, p=0.07) and at 2 years 12.9% vs 8.4% (HR 0.63, 95% CI 0.35 to 1.13, p=0.12) after simple versus complex treatment. In the subgroup treated by newer generation drug-eluting stents, MACE was 12.0% vs 5.6% (HR 0.45, 95% CI 0.17 to 1.17, p=0.10) after simple versus complex treatment.

Conclusion: In the treatment of bifurcation lesions involving a large SB with ostial stenosis, routine two-stent techniques did not improve outcome significantly compared with treatment by the simpler main vessel stenting technique after 2 years.

Trial registration number: NCT01496638.

Keywords: complex coronary lesions; coronary bifurcations; drug eluting stents.

Conflict of interest statement

Competing interests: IK received institutional research grants from Cordis, Abbott and speaker fee from Astra Zeneca. NRH has received institutional research grants from Cordis, Abbott, Terumo, Biosensors, Biotronik, Medis medical imaging, Reva Medical, Boston Scientific, St. Jude Medical and Medtronic and has received speaker fees and personal honorarium from St. Jude Medical, Terumo, Reva Medical and Biotronik. LOJ has received institutional research grants from Terumo, Biosensors and Biotronik. JFL has received institutional research grants from Cordis, Abbott, Terumo, Biosensors, Biotronik, Medis medical imaging, Reva Medical, Boston Scientific, Heartflow, St. Jude Medical and Medtronic and has received speaker fees from Biotronik, Biosensors, Tryton, Boston Scientific, St. Jude Medical, Terumo, Reva medical, Cordis, Astra Zeneca and Abbott. GL has received speaker fees from Astra Zeneca.

© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Patient flow chart. *Numbers in the two groups are not balanced at baseline due to block randomisation and sites with less than four inclusions. MV, main vessel; SB, side branch; FU, follow-up.

Figure 2

Kaplan-Meier curve for major adverse cardiac events (MACE). Clinical event curves showing MACE rates until 2 years.

Figure 3

Kaplan-Meier curves for clinical endpoints. Clinical event curves for cardiac death, non-procedural myocardial infarction and target lesion revascularisation until 2 years.

Figure 4

Subgroup analyses of the primary composite endpoint. Event rates are Kaplan-Meier estimates by time-to-event of the composite endpoint for major adverse cardiovascular events (MACE). The likelihood of interaction of the subgroup variable and allocated treatment is given by the p value for interaction. SB, side branch; DS%, diameter stenosis in %. Angiographic parameters are by visual estimation.