Clinical impact of bifurcation angle change between diastole and systole in complex stenting for left main distal bifurcation: The Milan and New-Tokyo (MITO) Registry

Dynamic assessment of the left main-left circumflex bending angle: Implications for ostial left circumflex artery in-stent restenosis after successful two-stent PCI

BACKGROUND

Two-stent techniques for percutaneous coronary intervention (PCI) on left main (LM) bifurcation (LMB) lesions are associated with an increased risk of in-stent restenosis (ISR) at left circumflex artery (LCx) ostium but the underlying mechanisms are incompletely understood. This study sought to investigate the association between cyclic change of LM-LCx bending angle (BA_LM-LCx) and the risk of ostial LCx ISR following two-stent techniques.

METHODS

In a retrospective cohort of patients undergoing two-stent PCI for LMB lesions, BA_LM-LCx and distal bifurcation angle (DBA) were computed with 3-dimensional angiographic reconstruction. The analysis was performed both at end-diastole and end-systole, and the angulation change throughout the cardiac cycle was defined as the cardiac motion-induced angulation change (∆_CAngle).

RESULTS

A total of 101 patients were included. The mean pre-procedural BA_LM-LCx was 66.8 ± 16.1° at end-diastole and 54.1 ± 13.3° at end-systole with a range of 13.0 ± 7.7°. Pre-procedural ∆_CBA_LM-LCx > 16.4° was the most relevant predictor of ostial LCx ISR (adjusted OR 11.58, 95% CI 4.04-33.19; p < 0.001). Post-procedural ∆_CBA_LM-LCx > 9.8° and stent-induced diastolic BA_LM-LCx change > 11.6° were also related with ostial LCx ISR. DBA was positively correlated with BA_LM-LCx and showed a weaker association of pre-procedural ∆_CDBA > 14.5° with ostial LCx ISR (adjusted OR 6.87, 95% CI 2.57-18.37; p < 0.001).

CONCLUSIONS

Three-dimensional angiographic bending angle is a feasible and reproducible novel method for LMB angulation measurement. A large pre-procedural cyclic change of BA_LM-LCx was associated with an increased risk of ostial LCx ISR following two-stent techniques.

Provisional Strategy for Left Main Stem Bifurcation Disease: A State-of-the-Art Review of Technique and Outcomes

Left main coronary artery (LMA) disease jeopardizes a large area of myocardium and increases the risk of major adverse cardiovascular events. LMCA disease is found in 5% to 7% of all diagnostic coronary angiographies, and more than 80% of the patients enrolled in recent large randomized controlled left main trials had distal left main bifurcation or trifurcation disease. Emerging clinical evidence from prospective all-comer registries and randomized trials has provided a solid basis for percutaneous coronary intervention as a treatment option in selected patients with unprotected LMCA disease; however, to date, no uniform recommendations as to optimal stenting strategy for LMCA bifurcation lesions exist. This review provides an overview of provisional stenting technique and escalation to 2-stent strategies in LMCA bifurcation lesions. Data from randomized controlled trials and registries are reviewed. Technical characteristics of optimal provisional LMCA stenting technique and angiographic and intravascular determinants of escalation are also summarized.

Impact of coronary bifurcation angle on the pathogenesis of atherosclerosis and clinical outcome of coronary bifurcation intervention–A scoping review

Background

A coronary bifurcation stenting is still a challenging issue due to frequent restenosis and stent thrombosis even with drug-eluting stents. The bifurcation angle (BA) between a main vessel and a side branch is one of the crucial determinants of coronary flow and shear stress that affect the plaque distribution. Previous bench and clinical studies have evaluated the impact of the BA between the proximal main vessel and the side branch (Angle A) and the BA between the distal main vessel and the side branch (Angle B) on the clinical outcomes of bifurcation stenting. However, the impact has not yet been fully elucidated due to a lack of statistical power or different manner of the assessment of BA.

Objectives

To analyze the published studies on coronary artery BA, the modalities used for assessment, and the impact of BA on interventions and attempt to define the pre-procedural protocols.

Data sources

A scoping review was performed using the Joanna Briggs Institute Methodology. A total of 52 relevant references were selected from PubMed, Cochrane Library, and CINAHL databases and categorized into three topic areas.

Results and conclusions

A wider Angle A is associated with the increased likelihood of carina shift and a wider Angle B, with that of side branch occlusion. A wider Angle B promotes stent malapposition and deformation in the side branch ostium and has been reported as an independent predictor of major adverse cardiac events after bifurcation stenting; however, improvement of the drug-eluting stent, refinement of the stenting technique, and accurate 3-dimensional assessment may attenuate the adverse clinical impact of a wider BA.

Implications of key findings

Assessment of the BA is necessary to predict the effect of bifurcation intervention procedure on the stent configuration and coronary flow at the bifurcated vessels. This will help to optimize stent selection and the stenting technique.