STEMI患者应用血栓抽吸装置的有效性——观点不一

No Consensus About Efficacy of Thrombus Aspiration in STEMI  

TAPAS研究显示：是否对所有STEMI患者应用血栓抽吸装置取决于术者的临床决策。另一项研究的亚组分析也显示有血栓高风险患者能否从血栓抽吸装置的应用中获益尚无定论。

TAPAS研究的主要终点是心肌染色分级，结果显示接受血栓抽吸装置的530例患者的分级比接受常规PCI的患者分级要高，并且ST段回落比例（70%）也比对照组高，P=0.001。1年随访发现，血栓抽吸装置组与对照组相比，其心源性死亡明显减少，P=0.003。荷兰的Gillian Jessurun博士解释说，无论是在短期还是长期疗效如生存率和无事件生存率上，血栓抽吸组都占据明显优势。他认为在对所有患者行PCI之前，应该常规应用血栓抽吸装置。

一项综合了9项随机研究的荟萃分析提示：应用手动血栓切除术很可能使心肌染色分级达到3，并且30天死亡率也可达到比较低的水平。
 
来自阿根廷的Fernando Cura博士对此持怀疑态度，他认为虽然说应用血栓抽吸装置可以使心肌微循环改善，并且这种改善可以通过心肌染色分级来衡量，但是迄今为止，没有任何一项研究得到与TAPAS研究相同的结果。他认为在将血栓抽吸装置应用于行直接PCI的STEMI患者身上，还需要更多信息做支撑。Cura 将TAPAS研究结果与EMERALD（另一项关于直接PCI中应用远端栓塞装置的临床疗效研究）做了对比。在EMERALD研究里，手术过程中应用的是5F抽吸导管和远端阻塞球囊，在TAPAs研究中用的是6F抽吸导管，但是在应用5F抽吸导管基础上，血流动力学改善程度更明显。EMERALD研究中，试验组与对照组死亡率分别为 3.4% 和 3.3%,P=0.94，在TAPAs研究中，该比例为3.6% vs. 6.7%，P=0.02，Cura解释说，尽管两组的远端栓塞发生率相同（P=0.14）但事实上，两组之间无论是在抽吸出来的血栓数量，还是抽吸物质的组织学成分均有很大差异。

（《医心评论》编辑 马秀芹 翻译 刘瑞琦 校对）

No Consensus About Efficacy of Thrombus Aspiration in STEMI
 

Thrombus aspiration should be performed in all STEMI patients depending on the clinical judgment of the operator, according to a researcher involved in TAPAS, the Thrombus Aspiration during Percutaneous Coronary Intervention in Acute Myocardial Infarction trial. Another researcher, however, contends that the subgroup at high embolic risk that would benefit from thrombus aspiration has not yet been identified.

Gillian Jessurun, MD, PhD, of the University Medical Center Groningen, Netherlands, said thrombus aspiration should be performed in all patients prior to PCI.

Myocardial blush grade, the primary endpoint of the TAPAS trial, was higher in the group receiving thrombus aspiration (n=530) than in the group receiving conventional PCI (n=530; P,.001). ST-segment resolution .70% was more frequent in the thrombus-aspiration group compared with the conventional-PCI group (P,.001).

At one year, there was a significant reduction in cardiac death in the thrombus group compared with the conventional-PCI group (P=0.003).

"Patients treated with thrombus aspiration adjunctive with PCI in STEMI have a better shot and [better] long-term clinical outcomes; for example, survival and event-free survival," Jessurun said.

A new meta-analysis of nine randomized controlled trials found that manual thrombectomy was more likely to result in myocardial blush grade 3 and better 30-day mortality (see Figure).
 
EMERALD vs. TAPAS

Fernando Cura, MD, PhD, of the Instituto Cardiovascular de Buenos Aires, Argentina, said that although thrombus aspiration results in myocardial circulation improvement as measured by myocardial blush score, no trial has yet demonstrated the same results as TAPAS. He said more information is needed about patients with STEMI before thrombus aspiration is added to primary PCI in that population.

Cura compared the data with EMERALD, the Enhanced Myocardial Efficacy and Removal by Aspiration of Liberated Debris trial, another large trial that examined the role of distal embolization during primary PCI.

The procedure in the EMERALD trial — using a 5F Export catheter (Medtronic) and distal balloon occlusion — demonstrated a better capacity to retrieve material compared with TAPAS, which used a 6F Export catheter (P=.78 for EMERALD vs. P,.001 for TAPAS).

In EMERALD, mortality was 3.4% in the protection group and 3.3% in the control group (P=.94). In TAPAS, mortality was 3.6% in the protection group and 6.7% in the control group (P=.02).

Although distal embolization was similar between the two studies (P=.14), "there is a large variation not only in the amount of captured material but in the histological composition of the captured material," Cura said.