Aims: To define the optimal kissing balloon inflation (KBI) after single-stent deployment in a coronary bifurcation model.

Methods and results: We deployed stents in main vessels (MV) followed by KBI in various conditions and compared the stent configurations. A) KBI at the operator’s discretion vs. under the guidelines of minimal balloon overlapping (MBO). Various stent configurations were observed after the former option, whereas similar maximal dilation points were observed under the MBO guidelines. B) Long balloon overlapping (LBO) vs. MBO with proximal MV dilated by a large balloon. The proximal MV was dilated to an ideal round shape with MBO versus an oval shape with LBO. C) Two-link vs. 3-link stents. Although the 2-link stent was advantageous to open the side branch, it incurred a risk of overdilatation of the proximal struts, whereas the 3-link stent preserved its structure. Computed simulations of coronary flow were analysed in the following left main coronary models: circle with a diameter of 4 and 5.5 mm, ellipse with longitudinal direction and tilt position. They revealed that the overdilated side was exposed to low shear stress regardless of its shape.

Conclusions: Optimal KBI can be achieved with MBO and proximal dilatation by an optimally sized balloon.