PCI後患者に対する術前アスピリン投与は有益である可能性がある(2017 AHA, Session LBS.05)

POISE-2 PCI：周術期低用量アスピリン投与はPCI後患者の死亡および非致死性MIのリスクを減少させる
POISE-2 PCI: Low-dose perioperative aspirin reduces risk of death or nonfatal MI in patients with prior PCI
過去に経皮的冠動脈インターベンション（PCI）を施行された患者において、非心臓手術直前、術中および術直後のアスピリン投与により、心臓に関する合併症を予防することができる、とのPOISE-2 試験の結果が2017 American Heart Association Scientific Sessions で発表され、Annals of Internal Medicine に掲載された。この結果から、周術期のアスピリン投与はPCI歴を有する非心臓手術患者1,000人毎に、59件の心筋梗塞を予防し8件の大出血イベントを来すことが示された。アスピリンはPCI歴の有無に関係なく、同程度に出血リスクを増大させた。
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A Canadian-led study has found that aspirin given just before, during and shortly after major non-cardiac surgery can prevent heart-related complications in patients who had a previous percutaneous coronary intervention (PCI) such as an angioplasty or stent.  The results of this substudy of the POISE trial was presented at the 2017 American Heart Association Scientific Sessions and published in the Annals of Internal Medicine.

"This is your next-door neighbor who had angioplasty five years ago, feels fine and needs to go in for hip surgery. It affects quite a large number of people," said the study's lead author, Michelle Graham, an interventional cardiologist and professor in the University of Alberta's Department of Medicine. She said 200 million adults around the world undergo major non-cardiac surgery annually.

The study examined the effect of aspirin in 470 patients with prior PCI patients undergoing noncardiac surgery. They were randomized to either aspirin or placebo.
The use of low-dose perioperative aspirin compared with placebo reduced the risk of the primary outcome – a composite of death or nonfatal myocardial infarction (MI).  "This effect was driven by a reduction in MI," Graham noted.  "This result significantly differed from those without prior PCI."

In patients with prior PCI, aspirin reduced the risk of the primary composite outcome (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.27-0.98, interaction p=0.0374).

Aspirin increased the risk of the composite of major and life-threatening bleeding in the overall trial population, to a similar extent in those with and without prior PCI (p=0.50).

These results suggest for every 1,000 patients with prior PCI who have noncardiac surgery, administration of perioperative aspirin would prevent 59 myocardial infarctions and cause 5 major bleeding events. Non-cardiac surgeries occur daily at hospitals around the world, so the study results will have a big impact on this patient group.

The POISE-2 trial is a large international study with sites in 135 centers in 23 countries. Patients with previous PCI were enrolled in 82 centers in 21 countries. 
In patients without a PCI, POISE-2 showed that aspirin did not reduce the risk of MI or death and led to an increased risk of major bleeding.

Of the 10,010 participants enrolled in the POISE-2 study, 470 had a previous PCI. Because patients with a prior PCI have an increased risk of cardiovascular complications after non-cardiac surgery, the group wanted to see whether the findings were the same in the subgroup.

This was the largest randomized trial of patients with PCI undergoing major non-cardiac surgery. Although aspirin reduced the risk of MI among patients in the study, it also slightly increased the risk of bleeding, though that risk did not appear worse than in the overall POISE-2 trial.

"There will be a big knowledge translation push with our colleagues in anesthesia and surgery to remind them that we want them to continue to give aspirin to this group of patients, when for most other groups we're recommending they stop," said Graham.

"This will potentially change the practice of anyone who does perioperative medicine," said Graham.

Funding for the Canadian study was largely provided by the Canadian Institutes of Health Research.