Drug Elution and Distal Protection During Percutaneous Coronary Intervention in ST Elevation Myocardial Infarction （幻灯）

试验描述：该试验的目的是比较DES与BMS在急性心肌梗死行直接PCI术中的应用情况。

药物与操作：行直接PCI的患者被随机分为DES组（n=313）和BMS组（n=313）。DES的选择是由调查人根据情况进行选择。8个月时进行造影随访。

主要发现：41%的患者的动脉梗阻发生在左前降支并且63%的患者发生单支血管病变。96%患者中应用血小板糖蛋白Ⅱb/Ⅲa受体拮抗剂。在DES组，47%患者应用西罗莫司洗脱支架，40%患者应用紫杉醇洗脱支架。90%患者的PCI术后即刻血流达到TIMI 3级。8个月造影随访发现，主要终点支架内晚期管腔丢失DES组小于BMS组（0.09mm vs. 0.69mm，p＜0.001），狭窄直径百分数（21.7% vs. 34.0%，p＜0.001），界定再狭窄率（4.8% vs. 16.6%，p＜0.001）。受TLR（5.1% vs. 13.1%，p＜0.001）的影响，MACE率DES组与BMS组（8.9% vs. 14.4%，p＜0.001）。DES组与BMS组在心肌梗死方面不存在差异（1.6% vs. 2.6%，p=0.42）。心源性死亡在DES组较高（4.2% vs. 1.6%，p=0.09）,整体死亡率也较高（5.1% vs. 2.6%，p=0.14）。支架内血栓发生率不存在差异，截至8个月时，每组均有7例患者发生明确的或可能的血栓。

解释：在因急性心梗行直接PCI治疗的患者中，与BMS组相比，DES组8个月晚期管腔丢失较低，但是心源性死亡率较高。先前关于直接PCI手术使用DES的试验规模小且结果不一，有些由于TLR减少促使联合事件减少，有些在联合事件上没有差别。目前研究显示DES有更高的死亡率。HORIZON AMI试验入选的3600名患者，比较直接PCI术中DES和BMS，因此，将是迄今为止此类研究中规模最大的。1年试验结果将在2008年秋季公布。

入选条件：冠心病  冠心病/急性心梗

治疗措施：支架  支架/药物洗脱

研究设计：随机入选626名患者，平均随访时间：8个月。病人平均年龄：62岁。女性患者所占比例为27%。

主要临床终点：8个月晚期管腔丢失。

次级临床终点：8个月心脏事件

患者群体：

12小时内急性突发典型胸痛；相邻导联ST段抬高＞4mm；主要冠脉高度狭窄，但可以用柔软的媒介尖端导丝再通；存在对梗死相关的动脉实施远端保护的可能性。

不能入选的情况

心肌梗死病史；应用纤维蛋白溶解剂治疗心肌梗死；左主干狭窄；腹主动脉高度钙化或髂股动脉疾病阻碍经股动脉达冠脉口的通路；肾脏衰竭；其他严重的心脏疾病；其他预期生存期少于1年的严重疾病；对氯吡格雷或造影剂过敏；1个月内有胃肠出血。

Title: Drug Elution and Distal Protection During Percutaneous Coronary Intervention in ST Elevation Myocardial Infarction (DEDICATION STENT - Presented at TCT 2007)

Year Presented: 2007
Topic(s): Interventional Cardiology
Summary Posted: 10/24/2007
Writer: Ms. Sabina A. Murphy  (view disclosure)
Reviewer: C. Michael Gibson, M.D., F.A.C.C.  (view disclosure)

The goal of the trial was to evaluate use of a drug-eluting stent compared with a bare metal stent among patients undergoing primary percutaneous coronary intervention (PCI) for acute myocardial infarction.

Drugs/Procedures Used
Patients undergoing primary PCI were randomized to use of a drug-eluting stent (DES; n = 313) or bare metal stent (BMS; n = 313). Choice of DES was at the discretion of the investigator. Angiographic follow-up was performed at 8 months.

Principal Findings
The infarct artery was the left anterior descending in 41% of patients and 63% had single vessel disease. Glycoprotein IIb/IIIa inhibitors were used in 96% of cases. In the DES arm, the sirolimus-eluting stent was used in 47% of cases and the paclitaxel-eluting stent in 40%. Final TIMI grade 3 flow was present in 90% of patients at the end of the PCI.

At 8 month angiographic follow-up, the primary endpoint of in-stent late lumen loss was smaller in the DES group compared with the BMS group (0.09 mm vs. 0.69 mm, p < 0.001). Percent diameter stenosis was lower in the DES group (21.7% vs. 34.0%, p < 0.001), as was binary restenosis (4.8% vs. 16.6%, p < 0.001). MACE at 8 months was lower in the DES group compared with the BMS group (8.9% vs. 14.4%, p < 0.001), driven by a reduction in TLR (5.1% vs. 13.1%, p < 0.001). There was no difference in myocardial infarction (1.6% vs. 2.6%, p = 0.42). Cardiac death trended higher in the DES group (4.2% vs. 1.6%, p = 0.09) as did overall mortality (5.1% vs. 2.6%, p = 0.14). There was no difference in stent thrombosis, with 7 cases of definite or probable thrombosis in each group by 8 months.

Interpretation
Among patients undergoing primary PCI for acute MI, use of a drug-eluting stent was associated with a reduction in late lumen loss at 8 months compared with use of a bare metal stent, but cardiac mortality trended higher.

Previous trials of DES use for primary PCI have been small and shown mixed results, with some showing a reduction in composite events driven by TLR and others showing no difference in composite events. There was a trend toward an increase in cardiac death with DES in the present study, although the increase was not explained by a difference in the rate of stent thrombosis, which was identical in the two arms. The 3,600 patient HORIZON AMI trial will compare DES with BMS in patients undergoing primary PCI and will be the largest study to date in this population. One year results of the trial are scheduled to be released in the fall of 2008.

Conditions
• Coronary heart disease
• Coronary heart disease / Acute MI
Therapies
 • Stent
 • Stent/drug-eluting
Study Design
Randomized.
Patients Screened: 1687
Patients Enrolled: 626
Mean Follow-Up: 8 months
Mean Patient Age: Mean age62 years
% Female: 27

Primary Endpoints
Late lumen loss at 8 months
Secondary Endpoints
Cardiac events at 8 months
Patient Population
Acute onset typical chest pain of within 12 hours; ST-elevation of > 4 mm in contiguous leads; high grade stenosis or occlusion of a native major coronary artery that can be crossed with a soft or intermediate tip guidewire; possibility to perform distal protection of the infarct-related artery
Exclusions:
History of previous myocardial infarction; use of fibrinolytic agents for the index infarction; left main stenosis; heavily calcification of abdominal aorta or occlusive iliofemoral disease hampering access to the coronary ostias by the femoral route; known renal failure; other significant cardiac disease; other severe disease with an expected survival < 1 year; known allergy to clopidogrel or contrast media; gastrointestinal bleeding within 1 month
References: Presented by Dr. Henning Kelbaek, at TCT 2007, Washington, DC.