Using IVUS imaging, plaque redistribution was described during stenting (14, 15). Plaque redistribution or 'plaque shift' across the carina of the bifurcation is regarded as the responsible mechanism that compromises the side branch lumen. Other predictors of side branch occlusion include significant branch-ostial stenosis, main vessel dissection, and acute coronary syndrome including acute MI (16). The later are important situations in which there may be a combination of thrombus on top of a lipid containing plaque.