薬剤溶出ステントと心筋梗塞

大規模登録データ解析の結果、薬剤溶出ステントはベアメタルステントと比較し急性心筋梗塞患者の予後を改善することが示唆された
Analysis of data from large registry suggests that drug-eluting stents offer better outcomes for patients with acute myocardial infarction than uncoated stents
薬剤溶出ステントはベアメタルステントと比較し死亡率は同等であるが再狭窄のリスクを軽減し、急性心筋梗塞患者の予後を改善するようであるとのLate-Breaking Clinical Trialの結果がAmerican College of Cardiology学会で発表された。研究者らはマサチューセッツ（米国）でステントを挿入された患者7,216人のデータを解析した。ここでは冠動脈インターベンション全例がデータベースに登録されている。薬剤溶出ステントを挿入された患者4,016人とベアメタルステントを挿入された患者3,200人のベースラインのリスクの差を補正するために、患者を最大63個の項目でマッチさせた。2年間のリスクで補正した血行再建術施行率は薬剤溶出ステント治療患者で有意に低く（15.5%対20.8%）、死亡率および再梗塞発症率は同等であった。筆者らはより長期のフォローアップデータを得るためさらに患者をモニターし続けているが、薬剤溶出ステントは抗血小板療法を遵守できる患者においては安全であると考えている。
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Drug-eluting stents appear to offer better outcomes for patients with acute myocardial infarction than uncoated stents, with similar mortality but significantly reduced risk for restenosis, according to a late-breaking clinical trial presented at the meeting of the American College of Cardiology.

"This study confirms that the same benefits that drug-eluting stents offer other patients in preventing restenosis of the coronary arteries are still there for patients with myocardial infarction, and there doesn't appear to be any trade-off in increased risk of repeat MI or death," said Laura Mauri, MD, MSC, an interventional cardiologist at Brigham and Women's Hospital, an assistant professor of medicine at Harvard Medical School, and chief scientific officer at the Harvard Clinical Research Institute, all in Boston.

To evaluate the long-term safety and effectiveness of drug-eluting stents, Mauri and her colleagues analyzed data from 7,216 patients who underwent stenting for acute MI in Massachusetts, where hospitals are required to submit data on all coronary interventions to a state database. Of these, 4,016 patients were treated with a drug-eluting stent and 3,200 were treated with a bare-metal stent. To adjust for differences in baseline risk, patients in the two groups were matched on up to 63 variables.

Researchers found that the two-year, risk-adjusted rate of revascularization was significantly lower in patients treated with drug-eluting stents when compared with bare-metal stents (15.5 percent versus 20.8 percent). Mortality was 10.4 percent and 13.2 percent, respectively, in the two groups, and repeat MI occurred in 9.5 percent and 11.0 percent, respectively.

"These findings are reassuring," Mauri said. "Although neither bare-metal stents nor drug-eluting stents were originally approved in the setting of acute myocardial infarction, it is probably the most important condition we treat with stents. I would feel comfortable considering drug-eluting stents on the basis of these results--with the caveats that treated patients must be able to take antiplatelet therapy and that we definitely want to see even longer-term follow-up."

The researchers plan to continue follow-up in Massachusetts and re-examine the findings when more data are available.