The Crush technique has evolved significantly since its introduction to the literature by Colombo et al in 2003, with multiple iterations including mini-crush (MC) and double kissing-crush (DKC) stenting techniques. The main principle of crush techniques for complex bifurcation lesions is to protrude the side branch (SB) stent towards the main branch to adequately cover the SB ostium and minimize the risk of SB ostium restenosis. It was noticed that the 4-5 mm protrusion of the SB stent resulted in a large volume of the crushed stent and the technique was modified into MC which aimed for approximately 1-2 mm protrusion by Galassi et al in 2007. Despite all the disadvantages of the crush technique, the final kissing balloon inflation (KBI) rate of this technique, along with several iterations has been up to 98%. Moreover, a recent meta-analysis showed that MC was associated with a reduction in risk of major cardiovascular events compared to provisional stenting, crush, and culotte techniques. The DKC is a planned 2-stent technique introduced by Chen et al. The ultimate innovation of this approach is that it is designed to increase the success rate of the final KBI. Provided recrossing of the crushed stent occurs through the proximal cell: another advantage of the DKC technique is to improve the success of KBI. The DKC significantly reduced major cardiovascular events (MACE) compared to provisional stenting, crush, TAP, and culotte. Until now, no clinical investigation has compared the DKC and MC in patients with complex left main bifurcation lesions. Therefore, this study sought to determine the clinical results of DKC and MC stenting techniques under long-term follow-up.

Inclusion Criteria:

• true complex left main bifurcation lesions
• stenting with double kissing-crush or mini-crush as a 2-stent strategy
• participation in regular clinical follow-up

Exclusion Criteria:

• prior history of coronary artery bypass grafting
• cardiogenic shock
• end-stage liver or kidney disease
• allergy to antiplatelet therapy or contrast media
• inappropriate dual antiplatelet therapy
• critically ill with < 1-year life expectancy
• absence of all medical records
• PCI for ST-segment elevation myocardial infarction or in-stent restenosis
• non-complex bifurcation lesions
• treated with a bare metal stent

This multicenter observational study was retrospectively conducted between January 2014 and January 2024, and patients who underwent percutaneous coronary intervention (PCI) for complex left main coronary bifurcation lesions.