Cleveland Clinic, Cleveland, Ohio.
Kardiologie I, Universitatsmedizin Mainz and DZHK Standort Rhein-Main, Germany.
JACC Cardiovasc Interv. 2018 Apr 9;11(7):638-644. doi: 10.1016/j.jcin.2017.11.042.
The aim of this study was to identify independent correlates of very late scaffold thrombosis (VLST) from an analysis of consecutively treated patients from 15 multicenter studies.
Recent analyses suggest an increased risk for VLST with the Absorb Bioresorbable Vascular Scaffold compared with drug-eluting stents, but insights as to correlates of risk are limited.
A total of 55 patients were identified with scaffold thrombosis. They were matched 2:1 with control subjects selected randomly from patients without thrombosis from the same study. Quantitative coronary angiography was available for 96.4% of patients. Multiple logistic and Cox regression analysis were used to identify significant independent outcome correlates from 6 pre-specified characteristics.
Patients had scaffold thrombosis at a median of 20 months (interquartile range: 17 to 27 months). Control subjects were followed for 36 months (interquartile range: 24 to 38 months). For the combined groups, reference vessel diameter (RVD) was 2.84 ± 0.50 mm, scaffold length was 26 ± 16 mm, and post-dilatation was performed in 56%. Univariate correlates of thrombosis were smaller nominal scaffold/RVD ratio (linear p = 0.001; ratio <1.18:1; odds ratio: 7.5; p = 0.002) and larger RVD (linear p = 0.001; >2.72 mm; odds ratio: 3.4; p = 0.001). Post-dilatation at ≥16 atm, post-dilatation balloon/scaffold ratio, final percentage stenosis, and dual antiplatelet therapy were not correlated with VLST. Only scaffold/RVD ratio remained a significant independent correlate of VLST (p = 0.001), as smaller ratio was correlated with RVD (p < 0.001). Post hoc analysis of 8 other potential covariates revealed no other correlates of outcome.
In the present analysis, the largest to date of its type, relative scaffold undersizing was the strongest determinant of VLST. Given current understanding of "scaffold dismantling," this finding likely has ramifications for all bioresorbable scaffolds.
本研究旨在从 15 项多中心研究中连续治疗的患者分析中确定导致极晚期支架血栓形成（VLST）的独立相关因素。
最近的分析表明，与药物洗脱支架相比，Absorb 生物可吸收血管支架发生 VLST 的风险增加，但对于风险相关因素的了解有限。
共确定了 55 例支架血栓形成患者。根据同一研究中无血栓形成的患者，按 2:1 比例随机选择对照患者进行匹配。96.4%的患者可进行定量冠状动脉造影。采用多变量逻辑回归和 Cox 回归分析从 6 个预先指定的特征中确定显著的独立预后相关因素。
患者的支架血栓形成中位数时间为 20 个月（四分位间距：17 至 27 个月）。对照患者的随访时间为 36 个月（四分位间距：24 至 38 个月）。对于联合组，参考血管直径（RVD）为 2.84±0.50mm，支架长度为 26±16mm，有 56%的患者行后扩张术。血栓形成的单变量相关因素为支架名义直径与 RVD 的比值较小（线性 p=0.001；比值<1.18:1；比值比：7.5；p=0.002）和 RVD 较大（线性 p=0.001；>2.72mm；比值比：3.4；p=0.001）。后扩张压力≥16atm、后扩张球囊/支架比值、最终狭窄百分比和双联抗血小板治疗与 VLST 无相关性。仅支架/RVD 比值仍然是 VLST 的独立显著相关因素（p=0.001），较小的比值与 RVD 相关（p<0.001）。对 8 个其他潜在协变量的事后分析未发现其他预后相关因素。
在目前的分析中，这是迄今为止此类分析中最大的一项研究，相对支架尺寸过小是导致 VLST 的最强决定因素。鉴于当前对“支架降解”的理解，这一发现可能对所有生物可吸收支架都有影响。
