Uncertainty remains about the effects of aspirin in patients with prior percutaneous coronary intervention (PCI) having noncardiac surgery.

To evaluate benefits and harms of perioperative aspirin in patients with prior PCI.

Nonprespecified subgroup analysis of a multicenter factorial trial. Computerized Internet randomization was done between 2010 and 2013. Patients, clinicians, data collectors, and outcome adjudicators were blinded to treatment assignment. (ClinicalTrials.gov: NCT01082874)

135 centers in 23 countries.

Adults aged 45 years or older who had or were at risk for atherosclerotic disease and were having noncardiac surgery. Exclusions were placement of a bare-metal stent within 6 weeks, placement of a drug-eluting stent within 1 year, or receipt of nonstudy aspirin within 72 hours before surgery.

Aspirin therapy (overall trial, n = 4998; subgroup, n = 234) or placebo (overall trial, n = 5012; subgroup, n = 236) initiated within 4 hours before surgery and continued throughout the perioperative period. Of the 470 subgroup patients, 99.9% completed follow-up.

The 30-day primary outcome was death or nonfatal myocardial infarction; bleeding was a secondary outcome.

In patients with prior PCI, aspirin reduced the risk for the primary outcome (absolute risk reduction, 5.5% [95% CI, 0.4% to 10.5%]; hazard ratio [HR], 0.50 [CI, 0.26 to 0.95]; P for interaction = 0.036) and for myocardial infarction (absolute risk reduction, 5.9% [CI, 1.0% to 10.8%]; HR, 0.44 [CI, 0.22 to 0.87]; P for interaction = 0.021). The effect on the composite of major and life-threatening bleeding in patients with prior PCI was uncertain (absolute risk increase, 1.3% [CI, −2.6% to 5.2%]). In the overall population, aspirin increased the risk for major bleeding (absolute risk increase, 0.8% [CI, 0.1% to 1.6%]; HR, 1.22 [CI, 1.01 to 1.48]; P for interaction = 0.50).

Nonprespecified subgroup analysis with small sample.

Perioperative aspirin may be more likely to benefit rather than harm patients with prior PCI.

Canadian Institutes of Health Research.

对于事先进行过非心脏手术的经皮冠状动脉介入治疗（PCI）的患者，阿司匹林的疗效尚不确定。

评估围手术期阿司匹林对既往PCI患者的利弊。

多中心析因试验的非预先指定的亚组分析。在2010年至2013年之间进行了计算机互联网随机化。患者，临床医生，数据收集者和结局判断者对治疗分配不知情。（ClinicalTrials.gov：NCT01082874）

在23个国家/地区设有135个中心。

45岁或以上的成年人患有动脉粥样硬化疾病或有患动脉粥样硬化疾病的风险，并且正在接受非心脏手术。不包括在手术后6周内放置裸金属支架，在手术后1年内放置药物洗脱支架或在手术前72小时内接受非研究类阿司匹林。

 在手术前4小时内开始使用阿司匹林治疗（整体试验，n  = 4998；亚组，n  = 234）或安慰剂（整体试验，n  = 5012；亚组，n = 236），并在整个围手术期持续进行。在470名亚组患者中，完成随访的占99.9％。

30天的主要结局是死亡或非致命性心肌梗塞。出血是次要结果。

在先前有PCI的患者中，阿司匹林降低了主要结局的风险（绝对风险降低5.5％[95％CI，0.4％至10.5％]；危险比[HR]，0.50 [CI，0.26至0.95]；P为相互作用= 0.036）和心肌梗死（绝对危险度降低5.9％[CI，1.0％至10.8％]； HR，0.44 [CI，0.22至0.87]；相互作用P = 0.021）。先前有PCI的患者对严重和危及生命的出血的综合影响尚不确定（绝对危险度增加1.3％[CI，-2.6％至5.2％]）。在总体人群中，阿司匹林增加了大出血的风险（绝对风险增加，0.8％[CI，0.1％至1.6％]； HR，1.22 [CI，1.01至1.48]；相互作用的P = 0.50）。

非预先确定的亚组分析，样品量少。

围手术期使用阿司匹林可能更有益于而不是损害先前接受过PCI的患者。

加拿大卫生研究所。