在第58届ACC会议上，一种简单而易行的小方法却给大家带来了大启示。在对进展性ST段抬高心肌梗死（STEMI）患者运往医院行经皮冠状动脉介入治疗（ PCI ）的途中，间歇性加压血压袖带阻断上臂血流，来营造远端缺血环境，有利于减少再灌注损伤并增加心肌残值。

    该项研究指出，预处理是指对远器官（如肾脏）制造短暂缺血可以保护将经受长期缺血的其他器官（如心脏）。这项前瞻性随机单盲试验预以确定远程缺血的预处理-在进行性STEMI中间歇性肢体缺血是否可产生类似的效果，进而在直接PCI中挽救心肌。

    来自丹麦Aarhus大学医学院的 Hans Erik Botker 教授说到，“我们已经在实验研究中证实了该观点，当我们通过结扎冠状动脉来人工诱发心肌梗死时，预处理可以减少心肌梗死面积和组织损伤。现在已将这个想法转移到临床中。当然，可以不使用预处理，因为谁也永远不知道何时会发生心肌梗死。因此，我们决定先在救护车上尝试这一概念。”

该单中心试验连续入选246例首发STEMI，入院后直接PCI 。所有患者的平均年龄为62岁（范围50至72岁），其中女性59例。所有患者的基线特征基本相似。在将患者转运往导管室的途中，分成预处理组和无预处理组。在预处理组，用血压袖带缠绕患者上臂并加压至200mmHg，使上肢缺血5分钟，然后释放加压使上肢再灌注5分钟，然后血压袖带重新阻断血流，反复四次。八小时内利用PCI治疗前注射99mTc-sestamibi和SPECT显像来判断两组患者的危险心肌（AAR）范围，PCI后30天时通过SPECT确定最终梗死面积（FIS），主要终点是挽救指数[AAR/( AAR- FIS)]。通过比较两组间的AAR，发现接受预处理的患者挽救指数更大[- 0.76（0.50-0.93）vs 0.56（0.35-0.90），P = 0.03]。与对照组相比，预处理组的最终梗死面积明显减少，并且未发现有副作用。

    预处理诱导抵抗心肌损伤，作为一种培训机制可以抵抗组织损伤。Botker教授认为，这个简单的干预在治疗STEMI中具有广泛的潜力。

（任芳 吕树铮  首都医科大学附属北京安贞医院）

英文原文

INTERMITTENTLY STOPPING BLOOD FLOW TO THE ARM LIMITS INFARCT SIZE IN EVOLVING MI Performed in Transit，Simple and Safe Intervention has Widespread Potential in the Treatment of STEMI

Orlando，Fl.–In patients with evolving ST-elevation myocardial infarction(STEMI)，remote ischemic perconditioning–intermittently inflating a blood pressure cuff to cut off blood flow to the arm while the patient is enroute to hospital for primary percutaneous coronary intervention (PCI)–reduces reperfusion injury and increases myocardial salvage，according to research presented during the i2 Summit at the American College of Cardiology’s 58 the annual scientific session.
Studies have shown that pre-conditioning，the concept of creating ischemia for short periods of time in a distant organ(i.e.，the kidney)，can protect another organ(i.e.，the heart)，during a subsequent prolonged period of ischemia.In this prospective randomized single-blinded trial， investigators sought to determine whether remote ischemic perconditioning–intermittent limb ischemia during evolving STEMI–could have a similar effect，and increase myocardial salvage in primary PCI.

“We have done this in experimental studies and have shown that when we induced an artificial myocardial infarction by ligating the coronary arteries，we could decrease the infarct size and decrease tissue damage，”said Hans Erik Botker，M.D.，Professor，Aarhus University Hospital Skejby，Aarhus，Denmark.“Now we have transferred this idea to the clinical setting. Of course you cannot use pre-conditioning because you never know when a myocardial infarction will occur.So we decided to try the concept in the ambulance.”

The single-center trial included 246 consecutive patients with a first STEMI admitted for primary PCI.The mean age of the patients was 62 years(range 50 to 72 years)and 59 patients were female.Their baseline characteristics were similar.
The patients were assigned to receive perconditioning or no perconditioning during transportation to the cath lab.In patients in the perconditioning group，a blood pressure cuff was put around the upper arm and inflated to 200 mmHg for five minutes to make the arm ischemic， and then released.Reperfusion of the arm was permitted for five minutes，and then the blood pressure cuff was re-applied.This procedure was repeated four times.

In both groups，the area of the myocardium at risk(AAR)was determined using 99mTc-sestamibi injected before the coronary intervention and by SPECT imaging within eight hours. The final infarct size(FIS)was determined by SPECT at 30 days post-intervention. The primary endpoint was the salvage index(AAR minus FIS divided by AAR).

The AAR was comparable in both groups.However，the salvage index was greater in the patients receiving perconditioning–0.76(0.50–0.93)vs 0.56(0.35–0.90)than in control patients(P=0.03).The final infarct size was decreased in the perconditioning group compared with the control group.No adverse effects of perconditioning were observed.

“Perconditioning induces resistance towards injury of the myocardium.It acts as a kind of training mechanism，it trains the tissue to resist injury，”B?tker said.“We believe that this simple intervention has widespread potential in the treatment of STEMI.”