Overtime evaluation of the vascular HEALing process after everolimus-eluting stent implantation by optical coherence tomography. The HEAL-EES study.
PURPOSE
Second-generation drug-eluting stent (DES) have shown a better safety and efficacy as compared to first generation DES due to an improved vascular healing process. This process has not been so far evaluated in vivo in an overtime fashion by optical coherent tomography (OCT). We sought to evaluate the vascular healing process after everolimus-eluting stent (EES) implantation at 6, 9 and 12months, by OCT.


METHODS
Consecutive 36 patients undergoing percutaneous coronary intervention with EES were randomized 1:1:1 to receive OCT imaging at 6 (group A), 9 (group B) or 12-month follow-up (group C). One patient from group C was excluded because of target lesion revascularization at 1-month, whereas 5 patients withdraw the informed consent. Finally, 30 patients were analyzed.


RESULTS
Neointimal thickness was not different between 3 groups (group A: 99.50 [94.06-127.79] μm, group B: 107.26 [83.48-133.59] μm, group C: 127.67 [102.51-138.49] μm; p=0.736). Although the percentage of "uncovered struts" was significantly higher in group A as compared to the other groups (8.0% vs. 4.4% vs. 2.9%, respectively; p=0.180), the ratio of uncovered to total struts per section <30% was similar between 3 groups (0.3% vs. 0.3% vs. 0%, respectively; p=1.000).


CONCLUSION
Healing process following EES implantation seems almost completed at 6-month follow-up. These data, which need to be confirmed in a larger study, may support the decision to shorten dual antiplatelet therapy.