Update on percutaneous intervention for left main coronary artery stenosis

Abstract

Percutaneous coronary intervention (PCI) using drug-eluting stents (DES) is currently considered as a viable alternative to coronary artery bypass graft surgery (CABG) for selected patients with left main coronary artery disease. The updated results of the landmark randomized trials comparing CABG versus PCI demonstrated comparable 5-year outcomes and are in line with the current guidelines that designate PCI as a reasonable treatment in this disease subset. Given that the completed randomized trials did not include contemporary DESs, the upcoming results of the ongoing trials evaluating the performance of new-generation DES compared with CABG (such as the EXCEL trial), may further help to clarify the current role and future recommendations of PCI for left main coronary artery disease. Apart from the recent stent technology, further improvements in outcomes after PCI may be possible when it is used with an integrated approach that combines functional concepts for decision-making, adjunctive imaging support and optimal pharmacotherapies.

Keywords:

• bifurcation
• drug-eluting stent
• fractional flow reserve
• intravascular ultrasound
• left main coronary artery
• outcomes
• percutaneous coronary intervention

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Cumulative evidences from landmark clinical trials indicate that PCI yields comparable outcomes to CABG.

• Frequent repeat revascularization is an inherent weakness of stent-related treatment, especially for the left main bifurcation lesions.

• The choice of PCI or CABG for treatment of unprotected LMCA disease should be based on the comprehensive clinical and anatomical features, and with consideration of the advantages and disadvantages of each procedure.

• The decision about whether to treat the intermediate LMCA stenosis should not be determined by the coronary angiogram alone.

• FFR-guided decision-making for the treatment of LMCA stenosis is generally accepted based on several outcome studies using FFR cut-off values of 0.75–0.80 as a surrogate for revascularization.

• In cases when an FFR measurement is not feasible, IVUS-derived MLA criteria (<4.5 mm²) has a potential to be used as a surrogate of functional significance of LMCA disease.

• Based on observational studies, the provisional 1-stent strategy showed more favorable long-term clinical outcomes compared with 2-stent techniques for left main bifurcation disease.

• In the 2-stent strategy for left main bifurcation disease, achieving sufficient post-stenting cross-sectional area (5.0 mm² for the LCX ostium, 6.3 mm² for the LAD ostium, 7.2 mm² for the polygon of confluence, and 8.2 mm² for the LMCA), guided by IVUS, is important.

• Incorporating the FFR-guided PCI strategy to treat the jailed LCX may reduce the incidence of unnecessary side branch intervention during provisional 1-stent approach.

• Future development of larger scaffold design with thinner struts, while maintaining mechanical strength, is needed to use bioresorbable scaffolds for the treatment of LMCA disease.

Notes