Background A growing volume of data suggests that simple manual thrombus aspiration followed by direct stenting improves myocardial reperfusion and clinical outcome compared with conventional primary PCI, but there is still limited data comparing the in vivo performance among different devices. This study aimed to compare the efficacy and operability of thrombus aspiration by the Diver CE （Invatec, Brescia, Italy） and ZEEK （Zeon Medical Inc., Tokyo, Japan） aspiration catheters in ST-segment elevation myocardial infarction （STEMI） and their impact on 3-month outcome.Methods From September 2004 to June 2008, 298 consecutive patients with STEMI who received manual thrombus aspiration were involved in a single center retrospective analysis. Of them, 229 and 69 were treated with Diver CE and ZEEK aspiration catheters, respectively. Primary endpoints were myocardial blush grade （MBG）, thrombolysis in myocardial infarction （TIMI） flow grade, ST-segment elevation resolution （STR）, device pushability and trackability as judged by the frequency of usage of dual guide wires and aspiration efficacy as indicated by size distribution of aspirated thrombi. Secondary endpoints were 3-month outcome including left ventricular end diastolic diameter （LVEDD）, left ventricular ejection fraction （LVEF）, as well as cardiac death, target lesion revascularization （TLR）, re-infarction and their combination as major adverse cardiac events （MACE）. Results Baseline characteristics were not different between the two groups expect for a higher frequency of temporary cardiac pacing in the ZEEK group （ZEEK） than in the Diver CE group （Diver CE） （0.44% vs 5.8%, P=0.002）. Visible retrieved thrombi were achieved in 65.9% of the Diver CE and 68.1% of the ZEEK （P=0.74）. Aspirated thrombi were categorized as small thrombi （〈3.5 mm）, moderate thrombi （3.5-7.0 mm） and large thrombi （〉7.0 mm）. Small thrombi were more frequently seen in the Diver CE （61.6% vs 42.6%）, whereas moder
ZHAO Han-jun YAN Hong-bing WANG Jian SONG Li LI Qing-xiang LI Shi-ying CHI Yun-peng WU Zheng ZHANG Xiao-jiang ZHAO Yong ZHENG Bin
