Vasomotor Response to Nitroglycerine Over 5 Years Follow-Up After Everolimus-Eluting Bioresorbable Scaffold Implantation

Objectives This study investigated the vasomotor response to nitroglycerine (NTG) up to 5 years after ABSORB implantation. Background There are no data regarding long-term vasomotor response after everolimus-eluting bioresorbable vascular scaffold ABSORB implantation. Methods We performed quantitative coronary angiography of the scaffolded and proximal and distal adjacent segments of patients from ABSORB Cohort B study before and after 200 μg of intracoronary NTG at 2, 3, and 5 years of follow-up. The mean changes of maximal and mean lumen diameters in the scaffolded and adjacent segments were calculated. Results The mean in-scaffold lumen diameter change in response to NTG showed a trend to increase over time with absolute values of 0.03 ± 0.09 mm, 0.05 ± 0.12 mm, and 0.07 ± 0.08 mm at 2, 3, and 5 years, respectively (p = 0.40). The maximal in-scaffold lumen diameter change significantly increased with values of 0.03 ± 0.14 mm, 0.06 ± 0.16 mm, and 0.11 ± 0.1 mm at 2, 3, and 5 years, respectively (p = 0.03). The normalized mean lumen diameter change after NTG in the scaffold relative to the adjacent segments was 51.9 ± 54.8% at 5 years of follow-up (p = 0.60). Conclusions Although there was a numerical increase of the vasomotor response to NTG after ABSORB implantation measured by quantitative coronary angiography with mean lumen diameter, the change was not statistically significant. However, the maximal lumen diameter changes increased over time from 2 to 5 years and attained statistical significance. The vasomotor response to NTG after ABSORB implantation moderately trended to increase, which is consistent with the progressive degradation and bioresorption of the scaffold, but the degree of vasomotor response remained lower in comparison with adjacent segments.