The incidence and potential mechanism of side-branch occlusion after implantation of bioresorbable scaffolds: Insights from ABSORB II

Side-branch occlusion (SBO) has been implicated as a contributing factor to the development of periprocedural myocardial infarction (PMI) after percutaneous coronary intervention. Mechanisms to explain the incidence of SBO after the metallic platform stent implantation have included mechanical vessel straightening and enlargement of the stented vessel, bifurcation carina shift, and/or coronary plaque shift into the orifice of the side branch. In a nonrandomized comparison using historical data, Absorb scaffold was associated with a higher incidence of postprocedural SBO compared with the everolimus-eluting stent (EES). There were no statistically significant differences in the incidence of cardiac biomarker (CB) rise and periprocedural myocardial infarction (PMI) between Absorb and EES. Overlapping of scaffolds or stents might be a precipitating factor of myocardial injury. Implantation of an oversized Absorb scaffold in a relatively small vessel appears to be associated with higher 1-year major adverse cardiac events (MACE) rates driven by more frequent early MI.