Dr. Bilal Çakır

Name of the Study: Comparison of noncompliant balloon with drug-coating balloon angioplasties for side branch after provisional stenting for patients with true coronary bifurcation lesions: The Prospective, Multicenter, Randomized DCB-BIF Trial

Published in Congress: TCT 2024

Link: https://www.tctmd.com/slide/comparison-noncompliant-balloon-drug-coating balloon-angioplasties-side-branch-after-0

Introduction:
In many bifurcation procedures initiated with a provisional strategy, after stenting the main branch, a need for stent implantation in the side branch arises, which increases the risk of restenosis, thrombosis, and the need for revascularization. Drug-coated balloons (DCB) are an attractive strategy for the treatment of side branches that develop critical stenosis after stenting of the main branch. However, the benefit of DCB in bifurcation lesions has not yet been clarified.

Objective:
The aim of the study is to compare DCB with non-compliant (NC) balloon in the treatment of critical side branches after stenting of the main branch in non-complex, true bifurcation lesions applied with provisional approach and to investigate the effect of DCB on the success of the provisional stenting technique.

Methods:
In a randomized controlled, multicenter study, 784 patients with true coronary bifurcation lesion who developed ?70% stenosis in the side branch after stenting of the main vessel were randomized into the DCB (391) and NC balloon (393) arms.
The inclusion criteria for the study are as follows: participants must be 18 years of age or older, present with silent ischemia, angina, or acute myocardial infarction (AMI) that occurred more than one week prior. Additionally, they should have a reference vessel diameter of 2.5 mm or greater, a baseline stenosis of 50% or more, a lesion length of less than 10 mm in the side branch, and the development of 70% or greater stenosis in the side branch ostium after stenting of the main branch. The exclusion criteria for the study are as follows: participants with an allergy to the study devices or medications, those intolerant to dual antiplatelet therapy, individuals with a life expectancy of less than 12 months, pregnant or nursing women, patients with a restenotic lesion, cases of severe calcification requiring rotational atherectomy, and those experiencing hemodynamic instability. The primary endpoint was major adverse cardiac events, a composite of cardiac death, target vessel myocardial infarction (MI) or target lesion revascularization at 1-year follow-up.

Results:
The mean age of the study population was 63.8±10.6 in the DCB arm and 63.6±10.5 in the NC balloon arm, with a male gender ratio of 78% and 75.6%, respectively. When the two groups were compared in terms of lesion and procedure characteristics, it was seen that the final kissing balloon was applied significantly more frequently in the NC balloon arm (n: 389/393, 98.9% vs n: 371/391, 94.9%; p<0.001), while no significant difference was found in terms of other characteristics. The primary composite endpoint occurred in 28 patients in the DCB arm and 49 patients in the NC balloon arm, with statistical significance in favor of DCB due to a reduction in MI (Kaplan-Meier ratio: 7.2% vs. 12.5%; HR: 0.56; 95% CI: 0.35-0.88; P=0.013). No significant differences were observed between the groups in terms of procedural success, conversion to a double-stent strategy, all-cause mortality, revascularization, and stent thrombosis.

Conclusions: 
In non-complex true bifurcation lesions undergoing provisional stenting strategy, in side branch osteal stenosis (?70%) after stenting of the main branch, DCB application is associated with a lower primary composite endpoint at 1 year compared with NC balloon. However, the clinical significance of periprocedural MI not requiring early revascularization contributing to statistical significance is unclear.

Comment:
This is the first large-scale, multicenter randomized controlled trial to demonstrate the superiority of DCB over NC balloon in provisional stenting of non-complex true coronary bifurcation lesions when balloon angioplasty is required for the side branch after stenting of the main branch. The benefit observed in the DCB arm of the study was largely due to a reduction in target vessel MI rates. An important point to consider is that more than 70% of MI events are periprocedural, and it is unclear how many of these are subclinical cases diagnosed solely by biomarker monitoring. Target vessel revascularization rates were quite low (<1.5%) and no difference was found between the groups. Clinical results over 1 year follow-up, side branch DCB treatment before main vessel stenting, comparisons with double stent strategies in complex bifurcation lesions, and efficacy in different demographic groups are the topics awaiting investigation.