A systematic two-stent approach in complex coronary bifurcation lesions is associated with a significantly greater improvement in clinical outcomes at one year than provisional stenting, according to the DEFINITION II study, presented at a late-breaking trial session at the PCR e-Course 2020 (25–27 June) and simultaneously published in the European Heart Journal.
Shao Liang Chen (Nanjing Medical University, Nanjing, China) informed the online audience that the lower rate of target lesion failure was “mainly driven by fewer target vessel myocardial infarctions and clinically-driven target lesion revascularisations. The incidence of stent thrombosis was comparable between the two groups.”
The study aimed to assess the benefits of the two-stent technique for patients with DEFINITION criteria-defined complex coronary bifurcation lesions. In total, 653 patients with complex bifurcation lesions at 49 international centres were randomly assigned to undergo the systematic two-stent technique (two-stent group, n=328) or provisional stenting (provisional group, n=325). The primary endpoint was the composite of target lesion failure at one-year follow-up, including cardiac death, target-vessel myocardial infarction, and clinically driven target lesion revascularisation. The safety endpoint was definite or probable stent thrombosis.
The researchers hypothesised a one-year target lesion failure rate of 14% in the provisional group versus 7% in the two-stent group.
At one year, target lesion failure occurred in 37 (11.4%) and 20 (6.1%) patients in the provisional and two-stent groups, respectively (77.8%, DK crush; hazard ratio [HR] 0.52, 95% confidence interval [CI] 0.30–0.90, p=0.019), largely driven by increased target vessel myocardial infarction (7.1%, HR 0.43, 95% CI 0.20–0.90, p=0.025), and clinically driven target lesion revascularisation (5.5%, HR 0.43, 95% CI 0.19–1.00, p=0.049) in the provisional group. One year after the index procedure, the incidence of cardiac death was 2.5% in the provisional group, non-significant to 2.1% in the two-stent group (HR 0.86, 95% CI 0.31–2.37, p=0.772).
Chen said: “DK crush is most commonly used in the two-stent group [77.8%], but TAP [T and small protrusion] is the most often used two-stent in the provisional group.”
He added: “A systematic two-stent approach is associated with a lower rate of one-year target lesion failure for patients with complex coronary bifurcation lesions, compared to the provisional approach. The underlying mechanisms for increased target vessel myocardial infarction after provisional stenting are unclear and further study is warranted.”
Assessing the significance of the findings for Cardiovascular News, Chen said: “Previously, there was no universally accepted stratification for defining the complexity of coronary artery bifurcation lesions—the DEFINITION criteria were built in our previous study. In the current study, among patients with DEFINITION criteria-defined complex coronary artery bifurcation lesions, a systematic two-stent approach (mainly DK crush stenting) demonstrates tremendous benefits. DEFINITION criteria could be used to differentiate simple from complex coronary artery bifurcation lesions.”