Although the EBC recommend provisional stent as the bifurcation PCIs of choice in the majority of bifurcation lesions, several factors may lead operators to adopt a 2-stent strategy. These factors consist of the importance of the SB and the risk of SB occlusion if a provisional stent was performed. Factors that operators tend to choose 2-stent strategy include true bifurcation lesions (Medina: 1,1,1; 1,0,1; or 0,1,1), SB diameter > 2.5 mm, length of SB lesion > 10–20 mm beyond SB ostium, and predicted adverse re-crossing after MV stent placement in the case of SB occlusion.

In the DKCRUSH-V trial performed by Chen et al. [5], DK crush had lower incidence of TLR and TVR on unprotected left main (LM) bifurcation lesions compared with provisional strategy. Unlike the EBC, based on this RCT, the European Society of Cardiology (ESC) and European Association for Cardio-Thoracic Surgery (EACTS) recommend the DK crush technique in true bifurcation lesions of the LM compared with the provisional technique.

DK crush, an iteration and modification of the classical crush technique for coronary bifurcation diseases, first described by Zhang et al. [10] The major difference between classic and DK crush is employing the first kissing balloon inflation (KBI) followed by the balloon crush of the SB stent implantation, leaving only one layer of metal struts at the ostial SB with minimal deformation, which furthers the second KBI after MV stenting. Compared with the classic crush technique, DK crush is superior in the rate of final KBI success and repeat intervention [4, 11].

Compared with other stent strategies, DK crush is associated with a higher rate of final KBI. Contrary to the 1-stent method, there is strong evidence to support the efficacy of final KBI in the 2-stent technique [12, 13]. Unsuccessful final KBI is associated with a significantly higher rate of MACE, TLR, and ST. Therefore, systematic FKB might be causally related to the better result of the DK crush over other stent techniques.