Academic Medical Center, Amsterdam, the Netherlands.
EuroIntervention. 2017 Apr 7;12(18):e2244-e2252. doi: 10.4244/EIJ-D-16-00740.
The aim of the study was to investigate long-term changes in lumen eccentricity and asymmetry at five years after implantation of the Absorb bioresorbable vascular scaffold (BVS).
Out of 101 patients from the ABSORB cohort B trial, 28 patients (29 lesions) with serial optical coherence tomography (OCT) examination at four different time points (cohort B1: post-procedure, six months, two, and five years [n=13]; cohort B2: post-procedure, one, three, and five years [n=16]) were evaluated. The longitudinal variance in lumen diameter was assessed by asymmetry index (AI). An asymmetric lesion was defined as AI >0.3. The circularity of the lumen or scaffold was evaluated by the eccentricity index calculated as minimal divided by maximal luminal or scaffold diameter per cross-section. The lowest lumen eccentricity index within a scaffold segment (EIL) <0.7 was defined as an eccentric lesion. Post procedure, an eccentric lesion was observed in 72.4% and became concentric in 93.1% at five years (post EIL 0.67±0.05 vs. five-year EIL 0.80±0.10, p=0.03) with a modest reduction of the lumen area from baseline to five years by 0.75±0.32 mm2. Asymmetric lumen morphology was observed in 93.1% (n=27) post implantation and persisted until five-year follow-up. On serial OCT analyses, there was a substantial increase in the scaffold EI during the first two years (post 0.70±0.06, six months 0.76±0.08, two years 0.85±0.07); then, it remained stable whereas the lumen circularity improved further. There were no significant differences in major adverse cardiac events regarding the lumen morphology over the five-year follow-up.
In patients treated with the Absorb BVS, the cross-sectional circularity improved over five years while the variance in longitudinal diameters remained. Regaining of lumen circularity is mainly caused by reshaping of the scaffold during the first two years.
本研究旨在探讨 Absorb 生物可吸收血管支架（BVS）置入 5 年后管腔偏心和不对称性的长期变化。
在 ABSORB 队列 B 试验的 101 例患者中，28 例患者（29 处病变）接受了 4 个不同时间点的连续光学相干断层扫描（OCT）检查（队列 B1：术后、6 个月、2 年和 5 年[13 例]；队列 B2：术后、1 年、3 年和 5 年[16 例]）。通过不对称指数（AI）评估管腔直径的纵向变化。AI>0.3 定义为不对称病变。通过计算每个横截面的最小和最大管腔或支架直径来评估管腔或支架的圆度，得到偏心指数。支架节段内最低管腔偏心指数（EIL）<0.7 定义为偏心病变。术后，72.4%的患者存在偏心病变，5 年后 93.1%的患者病变变得同心（术后 EIL 0.67±0.05 比 5 年 EIL 0.80±0.10，p=0.03），5 年时管腔面积较基线减少 0.75±0.32mm2。支架置入后 93.1%（n=27）的患者存在不对称管腔形态，直至 5 年随访时仍存在。在连续的 OCT 分析中，支架 EI 在最初 2 年内显著增加（术后 0.70±0.06，6 个月 0.76±0.08，2 年 0.85±0.07）；随后保持稳定，而管腔的圆度进一步改善。在 5 年随访期间，管腔形态没有导致主要不良心脏事件显著增加。
在接受 Absorb BVS 治疗的患者中，5 年内管腔的横截面积逐渐变圆，而纵向直径的变化保持不变。管腔圆度的恢复主要是由于前 2 年内支架的重塑。
