Percutaneous coronary interventions to implant bioresorbable vascular scaffolds (BVSs) were designed to reduce the late thrombotic events that occur with metallic stents.

To estimate the incidence of scaffold thrombosis after BVS implantation and compare everolimus-eluting BVSs with everolimus-eluting metallic stents (EESs) in terms of safety and efficacy at mid- and long-term follow-up in adults who had a percutaneous coronary intervention.

PubMed, EMBASE, the Cochrane Library, conference proceedings, and relevant Web sites from inception until 20 May 2017, without language restriction.

7 randomized trials and 38 observational studies (each with a minimum of 6 months and 100 patient-years of follow-up) in adults with coronary artery disease who had a BVS or an EES and reported scaffold or stent thrombosis (main outcome) or other secondary outcomes (such as death, myocardial infarction, or revascularization).

2 reviewers independently extracted study data, rated study quality, and assessed strength of evidence.

The pooled incidence of definite or probable scaffold thrombosis after BVS implantation was 1.8% (95% CI, 1.5% to 2.2%) at a median follow-up of 1 year (41 studies, 21 884 patients) and 0.8% (CI, 0.5% to 1.3%) beyond 1 year (14 studies, 4688 patients). Seven trials involving 5578 patients that directly compared BVSs with EESs showed an increased risk for definite or probable scaffold thrombosis (odds ratio [OR], 3.40 [CI, 2.01 to 5.76]) with BVSs at a median follow-up of 25 months. Increased risks were present at early (prominently subacute), late, and very late stages, and odds beyond 1 year were almost double those seen within 1 year. Bioresorbably vascular scaffolds increased risks for myocardial infarction (OR, 1.63 [CI, 1.26 to 2.10]), target lesion revascularization (OR, 1.31 [CI, 1.03 to 1.67]), and target lesion failure (OR, 1.37 [CI, 1.12 to 1.66]); the odds for these 3 end points also increased over time. The incidences of all-cause, cardiac, and noncardiac death and of target vessel and any revascularization did not differ.

Quality of observational studies was unclear, and some data were unpublished.

Compared with EESs, BVSs increased the risks for scaffold thrombosis and other thrombotic events at mid- and long-term follow-up, and risks increased over time.

National Natural Science Foundation of China.

植入生物可吸收血管支架（BVS）的经皮冠状动脉介入治疗旨在减少金属支架发生的晚期血栓事件。

评估 BVS 植入后支架血栓形成的发生率，并比较依维莫司洗脱 BVS 与依维莫司洗脱金属支架 (EES) 在接受经皮冠状动脉介入治疗的成人中长期随访时的安全性和有效性。

PubMed、EMBASE、Cochrane 图书馆、会议论文集和相关网站从开始到 2017 年 5 月 20 日，没有语言限制。

7 项随机试验和 38 项观察性研究（每项研究至少 6 个月和 100 患者年的随访）针对患有 BVS 或 EES 并报告支架或支架血栓形成（主要结果）或其他的冠状动脉疾病成人次要结局（如死亡、心肌梗死或血运重建）。

2名评价员独立提取研究数据，评定研究质量，评估证据强度。

在中位随访 1 年（41 项研究，21 884 名患者）和 0.8%（CI，0.5 % 至 1.3%）超过 1 年（14 项研究，4688 名患者）。涉及 5578 名患者的 7 项试验直接比较了 BVS 与 EES，结果显示，在中位随访 25 个月时，BVS 可增加明确或可能的支架血栓形成的风险（比值比 [OR]，3.40 [CI，2.01 至 5.76]）。早期（主要是亚急性）、晚期和非常晚期的风险增加，超过 1 年的几率几乎是 1 年内的两倍。生物可吸收血管支架增加了心肌梗死（OR，1.63 [CI，1.26 至 2.10]）、靶病变血运重建（OR，1.31 [CI，1.03 至 1.67]）和靶病变失败（OR，1.37 [CI，1. 12 至 1.66]）；这三个终点的几率也随着时间的推移而增加。全因、心源性和非心源性死亡以及靶血管和任何血运重建的发生率没有差异。

观察性研究的质量尚不清楚，一些数据未发表。

与 EESs 相比，BVSs 在中长期随访中增加了支架血栓形成和其他血栓事件的风险，并且风险随着时间的推移而增加。

国家自然科学基金委。